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Diffstat (limited to 'gcc/gimplify.c')
| -rw-r--r-- | gcc/gimplify.c | 6483 |
1 files changed, 6483 insertions, 0 deletions
diff --git a/gcc/gimplify.c b/gcc/gimplify.c new file mode 100644 index 0000000..e6c0d1f --- /dev/null +++ b/gcc/gimplify.c @@ -0,0 +1,6483 @@ +/* Tree lowering pass. This pass converts the GENERIC functions-as-trees + tree representation into the GIMPLE form. + Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. + Major work done by Sebastian Pop <s.pop@laposte.net>, + Diego Novillo <dnovillo@redhat.com> and Jason Merrill <jason@redhat.com>. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify it under +the terms of the GNU General Public License as published by the Free +Software Foundation; either version 2, or (at your option) any later +version. + +GCC is distributed in the hope that it will be useful, but WITHOUT ANY +WARRANTY; without even the implied warranty of MERCHANTABILITY or +FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING. If not, write to the Free +Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301, USA. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "tree.h" +#include "rtl.h" +#include "varray.h" +#include "tree-gimple.h" +#include "tree-inline.h" +#include "diagnostic.h" +#include "langhooks.h" +#include "langhooks-def.h" +#include "tree-flow.h" +#include "cgraph.h" +#include "timevar.h" +#include "except.h" +#include "hashtab.h" +#include "flags.h" +#include "real.h" +#include "function.h" +#include "output.h" +#include "expr.h" +#include "ggc.h" +#include "toplev.h" +#include "target.h" +#include "optabs.h" +#include "pointer-set.h" + + +enum gimplify_omp_var_data +{ + GOVD_SEEN = 1, + GOVD_EXPLICIT = 2, + GOVD_SHARED = 4, + GOVD_PRIVATE = 8, + GOVD_FIRSTPRIVATE = 16, + GOVD_LASTPRIVATE = 32, + GOVD_REDUCTION = 64, + GOVD_LOCAL = 128, + GOVD_DEBUG_PRIVATE = 256, + GOVD_DATA_SHARE_CLASS = (GOVD_SHARED | GOVD_PRIVATE | GOVD_FIRSTPRIVATE + | GOVD_LASTPRIVATE | GOVD_REDUCTION | GOVD_LOCAL) +}; + +struct gimplify_omp_ctx +{ + struct gimplify_omp_ctx *outer_context; + splay_tree variables; + struct pointer_set_t *privatized_types; + location_t location; + enum omp_clause_default_kind default_kind; + bool is_parallel; + bool is_combined_parallel; +}; + +struct gimplify_ctx +{ + struct gimplify_ctx *prev_context; + + tree current_bind_expr; + tree temps; + tree conditional_cleanups; + tree exit_label; + tree return_temp; + + VEC(tree,heap) *case_labels; + /* The formal temporary table. Should this be persistent? */ + htab_t temp_htab; + + int conditions; + bool save_stack; + bool into_ssa; +}; + +static struct gimplify_ctx *gimplify_ctxp; +static struct gimplify_omp_ctx *gimplify_omp_ctxp; + + + +/* Formal (expression) temporary table handling: Multiple occurrences of + the same scalar expression are evaluated into the same temporary. */ + +typedef struct gimple_temp_hash_elt +{ + tree val; /* Key */ + tree temp; /* Value */ +} elt_t; + +/* Forward declarations. */ +static enum gimplify_status gimplify_compound_expr (tree *, tree *, bool); +#ifdef ENABLE_CHECKING +static bool cpt_same_type (tree a, tree b); +#endif + + +/* Return a hash value for a formal temporary table entry. */ + +static hashval_t +gimple_tree_hash (const void *p) +{ + tree t = ((const elt_t *) p)->val; + return iterative_hash_expr (t, 0); +} + +/* Compare two formal temporary table entries. */ + +static int +gimple_tree_eq (const void *p1, const void *p2) +{ + tree t1 = ((const elt_t *) p1)->val; + tree t2 = ((const elt_t *) p2)->val; + enum tree_code code = TREE_CODE (t1); + + if (TREE_CODE (t2) != code + || TREE_TYPE (t1) != TREE_TYPE (t2)) + return 0; + + if (!operand_equal_p (t1, t2, 0)) + return 0; + + /* Only allow them to compare equal if they also hash equal; otherwise + results are nondeterminate, and we fail bootstrap comparison. */ + gcc_assert (gimple_tree_hash (p1) == gimple_tree_hash (p2)); + + return 1; +} + +/* Set up a context for the gimplifier. */ + +void +push_gimplify_context (void) +{ + struct gimplify_ctx *c; + + c = (struct gimplify_ctx *) xcalloc (1, sizeof (struct gimplify_ctx)); + c->prev_context = gimplify_ctxp; + if (optimize) + c->temp_htab = htab_create (1000, gimple_tree_hash, gimple_tree_eq, free); + + gimplify_ctxp = c; +} + +/* Tear down a context for the gimplifier. If BODY is non-null, then + put the temporaries into the outer BIND_EXPR. Otherwise, put them + in the unexpanded_var_list. */ + +void +pop_gimplify_context (tree body) +{ + struct gimplify_ctx *c = gimplify_ctxp; + tree t; + + gcc_assert (c && !c->current_bind_expr); + gimplify_ctxp = c->prev_context; + + for (t = c->temps; t ; t = TREE_CHAIN (t)) + DECL_GIMPLE_FORMAL_TEMP_P (t) = 0; + + if (body) + declare_vars (c->temps, body, false); + else + record_vars (c->temps); + + if (optimize) + htab_delete (c->temp_htab); + free (c); +} + +static void +gimple_push_bind_expr (tree bind) +{ + TREE_CHAIN (bind) = gimplify_ctxp->current_bind_expr; + gimplify_ctxp->current_bind_expr = bind; +} + +static void +gimple_pop_bind_expr (void) +{ + gimplify_ctxp->current_bind_expr + = TREE_CHAIN (gimplify_ctxp->current_bind_expr); +} + +tree +gimple_current_bind_expr (void) +{ + return gimplify_ctxp->current_bind_expr; +} + +/* Returns true iff there is a COND_EXPR between us and the innermost + CLEANUP_POINT_EXPR. This info is used by gimple_push_cleanup. */ + +static bool +gimple_conditional_context (void) +{ + return gimplify_ctxp->conditions > 0; +} + +/* Note that we've entered a COND_EXPR. */ + +static void +gimple_push_condition (void) +{ +#ifdef ENABLE_CHECKING + if (gimplify_ctxp->conditions == 0) + gcc_assert (!gimplify_ctxp->conditional_cleanups); +#endif + ++(gimplify_ctxp->conditions); +} + +/* Note that we've left a COND_EXPR. If we're back at unconditional scope + now, add any conditional cleanups we've seen to the prequeue. */ + +static void +gimple_pop_condition (tree *pre_p) +{ + int conds = --(gimplify_ctxp->conditions); + + gcc_assert (conds >= 0); + if (conds == 0) + { + append_to_statement_list (gimplify_ctxp->conditional_cleanups, pre_p); + gimplify_ctxp->conditional_cleanups = NULL_TREE; + } +} + +/* A stable comparison routine for use with splay trees and DECLs. */ + +static int +splay_tree_compare_decl_uid (splay_tree_key xa, splay_tree_key xb) +{ + tree a = (tree) xa; + tree b = (tree) xb; + + return DECL_UID (a) - DECL_UID (b); +} + +/* Create a new omp construct that deals with variable remapping. */ + +static struct gimplify_omp_ctx * +new_omp_context (bool is_parallel, bool is_combined_parallel) +{ + struct gimplify_omp_ctx *c; + + c = XCNEW (struct gimplify_omp_ctx); + c->outer_context = gimplify_omp_ctxp; + c->variables = splay_tree_new (splay_tree_compare_decl_uid, 0, 0); + c->privatized_types = pointer_set_create (); + c->location = input_location; + c->is_parallel = is_parallel; + c->is_combined_parallel = is_combined_parallel; + c->default_kind = OMP_CLAUSE_DEFAULT_SHARED; + + return c; +} + +/* Destroy an omp construct that deals with variable remapping. */ + +static void +delete_omp_context (struct gimplify_omp_ctx *c) +{ + splay_tree_delete (c->variables); + pointer_set_destroy (c->privatized_types); + XDELETE (c); +} + +static void omp_add_variable (struct gimplify_omp_ctx *, tree, unsigned int); +static bool omp_notice_variable (struct gimplify_omp_ctx *, tree, bool); + +/* A subroutine of append_to_statement_list{,_force}. T is not NULL. */ + +static void +append_to_statement_list_1 (tree t, tree *list_p) +{ + tree list = *list_p; + tree_stmt_iterator i; + + if (!list) + { + if (t && TREE_CODE (t) == STATEMENT_LIST) + { + *list_p = t; + return; + } + *list_p = list = alloc_stmt_list (); + } + + i = tsi_last (list); + tsi_link_after (&i, t, TSI_CONTINUE_LINKING); +} + +/* Add T to the end of the list container pointed to by LIST_P. + If T is an expression with no effects, it is ignored. */ + +void +append_to_statement_list (tree t, tree *list_p) +{ + if (t && TREE_SIDE_EFFECTS (t)) + append_to_statement_list_1 (t, list_p); +} + +/* Similar, but the statement is always added, regardless of side effects. */ + +void +append_to_statement_list_force (tree t, tree *list_p) +{ + if (t != NULL_TREE) + append_to_statement_list_1 (t, list_p); +} + +/* Both gimplify the statement T and append it to LIST_P. */ + +void +gimplify_and_add (tree t, tree *list_p) +{ + gimplify_stmt (&t); + append_to_statement_list (t, list_p); +} + +/* Strip off a legitimate source ending from the input string NAME of + length LEN. Rather than having to know the names used by all of + our front ends, we strip off an ending of a period followed by + up to five characters. (Java uses ".class".) */ + +static inline void +remove_suffix (char *name, int len) +{ + int i; + + for (i = 2; i < 8 && len > i; i++) + { + if (name[len - i] == '.') + { + name[len - i] = '\0'; + break; + } + } +} + +/* Create a nameless artificial label and put it in the current function + context. Returns the newly created label. */ + +tree +create_artificial_label (void) +{ + tree lab = build_decl (LABEL_DECL, NULL_TREE, void_type_node); + + DECL_ARTIFICIAL (lab) = 1; + DECL_IGNORED_P (lab) = 1; + DECL_CONTEXT (lab) = current_function_decl; + return lab; +} + +/* Subroutine for find_single_pointer_decl. */ + +static tree +find_single_pointer_decl_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, + void *data) +{ + tree *pdecl = (tree *) data; + + if (DECL_P (*tp) && POINTER_TYPE_P (TREE_TYPE (*tp))) + { + if (*pdecl) + { + /* We already found a pointer decl; return anything other + than NULL_TREE to unwind from walk_tree signalling that + we have a duplicate. */ + return *tp; + } + *pdecl = *tp; + } + + return NULL_TREE; +} + +/* Find the single DECL of pointer type in the tree T and return it. + If there are zero or more than one such DECLs, return NULL. */ + +static tree +find_single_pointer_decl (tree t) +{ + tree decl = NULL_TREE; + + if (walk_tree (&t, find_single_pointer_decl_1, &decl, NULL)) + { + /* find_single_pointer_decl_1 returns a nonzero value, causing + walk_tree to return a nonzero value, to indicate that it + found more than one pointer DECL. */ + return NULL_TREE; + } + + return decl; +} + +/* Create a new temporary name with PREFIX. Returns an identifier. */ + +static GTY(()) unsigned int tmp_var_id_num; + +tree +create_tmp_var_name (const char *prefix) +{ + char *tmp_name; + + if (prefix) + { + char *preftmp = ASTRDUP (prefix); + + remove_suffix (preftmp, strlen (preftmp)); + prefix = preftmp; + } + + ASM_FORMAT_PRIVATE_NAME (tmp_name, prefix ? prefix : "T", tmp_var_id_num++); + return get_identifier (tmp_name); +} + + +/* Create a new temporary variable declaration of type TYPE. + Does NOT push it into the current binding. */ + +tree +create_tmp_var_raw (tree type, const char *prefix) +{ + tree tmp_var; + tree new_type; + + /* Make the type of the variable writable. */ + new_type = build_type_variant (type, 0, 0); + TYPE_ATTRIBUTES (new_type) = TYPE_ATTRIBUTES (type); + + tmp_var = build_decl (VAR_DECL, prefix ? create_tmp_var_name (prefix) : NULL, + type); + + /* The variable was declared by the compiler. */ + DECL_ARTIFICIAL (tmp_var) = 1; + /* And we don't want debug info for it. */ + DECL_IGNORED_P (tmp_var) = 1; + + /* Make the variable writable. */ + TREE_READONLY (tmp_var) = 0; + + DECL_EXTERNAL (tmp_var) = 0; + TREE_STATIC (tmp_var) = 0; + TREE_USED (tmp_var) = 1; + + return tmp_var; +} + +/* Create a new temporary variable declaration of type TYPE. DOES push the + variable into the current binding. Further, assume that this is called + only from gimplification or optimization, at which point the creation of + certain types are bugs. */ + +tree +create_tmp_var (tree type, const char *prefix) +{ + tree tmp_var; + + /* We don't allow types that are addressable (meaning we can't make copies), + or incomplete. We also used to reject every variable size objects here, + but now support those for which a constant upper bound can be obtained. + The processing for variable sizes is performed in gimple_add_tmp_var, + point at which it really matters and possibly reached via paths not going + through this function, e.g. after direct calls to create_tmp_var_raw. */ + gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type)); + + tmp_var = create_tmp_var_raw (type, prefix); + gimple_add_tmp_var (tmp_var); + return tmp_var; +} + +/* Given a tree, try to return a useful variable name that we can use + to prefix a temporary that is being assigned the value of the tree. + I.E. given <temp> = &A, return A. */ + +const char * +get_name (tree t) +{ + tree stripped_decl; + + stripped_decl = t; + STRIP_NOPS (stripped_decl); + if (DECL_P (stripped_decl) && DECL_NAME (stripped_decl)) + return IDENTIFIER_POINTER (DECL_NAME (stripped_decl)); + else + { + switch (TREE_CODE (stripped_decl)) + { + case ADDR_EXPR: + return get_name (TREE_OPERAND (stripped_decl, 0)); + break; + default: + return NULL; + } + } +} + +/* Create a temporary with a name derived from VAL. Subroutine of + lookup_tmp_var; nobody else should call this function. */ + +static inline tree +create_tmp_from_val (tree val) +{ + return create_tmp_var (TYPE_MAIN_VARIANT (TREE_TYPE (val)), get_name (val)); +} + +/* Create a temporary to hold the value of VAL. If IS_FORMAL, try to reuse + an existing expression temporary. */ + +static tree +lookup_tmp_var (tree val, bool is_formal) +{ + tree ret; + + /* If not optimizing, never really reuse a temporary. local-alloc + won't allocate any variable that is used in more than one basic + block, which means it will go into memory, causing much extra + work in reload and final and poorer code generation, outweighing + the extra memory allocation here. */ + if (!optimize || !is_formal || TREE_SIDE_EFFECTS (val)) + ret = create_tmp_from_val (val); + else + { + elt_t elt, *elt_p; + void **slot; + + elt.val = val; + slot = htab_find_slot (gimplify_ctxp->temp_htab, (void *)&elt, INSERT); + if (*slot == NULL) + { + elt_p = XNEW (elt_t); + elt_p->val = val; + elt_p->temp = ret = create_tmp_from_val (val); + *slot = (void *) elt_p; + } + else + { + elt_p = (elt_t *) *slot; + ret = elt_p->temp; + } + } + + if (is_formal) + DECL_GIMPLE_FORMAL_TEMP_P (ret) = 1; + + return ret; +} + +/* Returns a formal temporary variable initialized with VAL. PRE_P is as + in gimplify_expr. Only use this function if: + + 1) The value of the unfactored expression represented by VAL will not + change between the initialization and use of the temporary, and + 2) The temporary will not be otherwise modified. + + For instance, #1 means that this is inappropriate for SAVE_EXPR temps, + and #2 means it is inappropriate for && temps. + + For other cases, use get_initialized_tmp_var instead. */ + +static tree +internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal) +{ + tree t, mod; + + gimplify_expr (&val, pre_p, post_p, is_gimple_formal_tmp_rhs, fb_rvalue); + + t = lookup_tmp_var (val, is_formal); + + if (is_formal) + { + tree u = find_single_pointer_decl (val); + + if (u && TREE_CODE (u) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (u)) + u = DECL_GET_RESTRICT_BASE (u); + if (u && TYPE_RESTRICT (TREE_TYPE (u))) + { + if (DECL_BASED_ON_RESTRICT_P (t)) + gcc_assert (u == DECL_GET_RESTRICT_BASE (t)); + else + { + DECL_BASED_ON_RESTRICT_P (t) = 1; + SET_DECL_RESTRICT_BASE (t, u); + } + } + } + + if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE) + DECL_COMPLEX_GIMPLE_REG_P (t) = 1; + + mod = build2 (INIT_EXPR, TREE_TYPE (t), t, val); + + if (EXPR_HAS_LOCATION (val)) + SET_EXPR_LOCUS (mod, EXPR_LOCUS (val)); + else + SET_EXPR_LOCATION (mod, input_location); + + /* gimplify_modify_expr might want to reduce this further. */ + gimplify_and_add (mod, pre_p); + + /* If we're gimplifying into ssa, gimplify_modify_expr will have + given our temporary an ssa name. Find and return it. */ + if (gimplify_ctxp->into_ssa) + t = TREE_OPERAND (mod, 0); + + return t; +} + +/* Returns a formal temporary variable initialized with VAL. PRE_P + points to a statement list where side-effects needed to compute VAL + should be stored. */ + +tree +get_formal_tmp_var (tree val, tree *pre_p) +{ + return internal_get_tmp_var (val, pre_p, NULL, true); +} + +/* Returns a temporary variable initialized with VAL. PRE_P and POST_P + are as in gimplify_expr. */ + +tree +get_initialized_tmp_var (tree val, tree *pre_p, tree *post_p) +{ + return internal_get_tmp_var (val, pre_p, post_p, false); +} + +/* Declares all the variables in VARS in SCOPE. If DEBUG_INFO is + true, generate debug info for them; otherwise don't. */ + +void +declare_vars (tree vars, tree scope, bool debug_info) +{ + tree last = vars; + if (last) + { + tree temps, block; + + /* C99 mode puts the default 'return 0;' for main outside the outer + braces. So drill down until we find an actual scope. */ + while (TREE_CODE (scope) == COMPOUND_EXPR) + scope = TREE_OPERAND (scope, 0); + + gcc_assert (TREE_CODE (scope) == BIND_EXPR); + + temps = nreverse (last); + + block = BIND_EXPR_BLOCK (scope); + if (!block || !debug_info) + { + TREE_CHAIN (last) = BIND_EXPR_VARS (scope); + BIND_EXPR_VARS (scope) = temps; + } + else + { + /* We need to attach the nodes both to the BIND_EXPR and to its + associated BLOCK for debugging purposes. The key point here + is that the BLOCK_VARS of the BIND_EXPR_BLOCK of a BIND_EXPR + is a subchain of the BIND_EXPR_VARS of the BIND_EXPR. */ + if (BLOCK_VARS (block)) + BLOCK_VARS (block) = chainon (BLOCK_VARS (block), temps); + else + { + BIND_EXPR_VARS (scope) = chainon (BIND_EXPR_VARS (scope), temps); + BLOCK_VARS (block) = temps; + } + } + } +} + +/* For VAR a VAR_DECL of variable size, try to find a constant upper bound + for the size and adjust DECL_SIZE/DECL_SIZE_UNIT accordingly. Abort if + no such upper bound can be obtained. */ + +static void +force_constant_size (tree var) +{ + /* The only attempt we make is by querying the maximum size of objects + of the variable's type. */ + + HOST_WIDE_INT max_size; + + gcc_assert (TREE_CODE (var) == VAR_DECL); + + max_size = max_int_size_in_bytes (TREE_TYPE (var)); + + gcc_assert (max_size >= 0); + + DECL_SIZE_UNIT (var) + = build_int_cst (TREE_TYPE (DECL_SIZE_UNIT (var)), max_size); + DECL_SIZE (var) + = build_int_cst (TREE_TYPE (DECL_SIZE (var)), max_size * BITS_PER_UNIT); +} + +void +gimple_add_tmp_var (tree tmp) +{ + gcc_assert (!TREE_CHAIN (tmp) && !DECL_SEEN_IN_BIND_EXPR_P (tmp)); + + /* Later processing assumes that the object size is constant, which might + not be true at this point. Force the use of a constant upper bound in + this case. */ + if (!host_integerp (DECL_SIZE_UNIT (tmp), 1)) + force_constant_size (tmp); + + DECL_CONTEXT (tmp) = current_function_decl; + DECL_SEEN_IN_BIND_EXPR_P (tmp) = 1; + + if (gimplify_ctxp) + { + TREE_CHAIN (tmp) = gimplify_ctxp->temps; + gimplify_ctxp->temps = tmp; + + /* Mark temporaries local within the nearest enclosing parallel. */ + if (gimplify_omp_ctxp) + { + struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp; + while (ctx && !ctx->is_parallel) + ctx = ctx->outer_context; + if (ctx) + omp_add_variable (ctx, tmp, GOVD_LOCAL | GOVD_SEEN); + } + } + else if (cfun) + record_vars (tmp); + else + declare_vars (tmp, DECL_SAVED_TREE (current_function_decl), false); +} + +/* Determines whether to assign a locus to the statement STMT. */ + +static bool +should_carry_locus_p (tree stmt) +{ + /* Don't emit a line note for a label. We particularly don't want to + emit one for the break label, since it doesn't actually correspond + to the beginning of the loop/switch. */ + if (TREE_CODE (stmt) == LABEL_EXPR) + return false; + + /* Do not annotate empty statements, since it confuses gcov. */ + if (!TREE_SIDE_EFFECTS (stmt)) + return false; + + return true; +} + +static void +annotate_one_with_locus (tree t, location_t locus) +{ + if (EXPR_P (t) && ! EXPR_HAS_LOCATION (t) && should_carry_locus_p (t)) + SET_EXPR_LOCATION (t, locus); +} + +void +annotate_all_with_locus (tree *stmt_p, location_t locus) +{ + tree_stmt_iterator i; + + if (!*stmt_p) + return; + + for (i = tsi_start (*stmt_p); !tsi_end_p (i); tsi_next (&i)) + { + tree t = tsi_stmt (i); + + /* Assuming we've already been gimplified, we shouldn't + see nested chaining constructs anymore. */ + gcc_assert (TREE_CODE (t) != STATEMENT_LIST + && TREE_CODE (t) != COMPOUND_EXPR); + + annotate_one_with_locus (t, locus); + } +} + +/* Similar to copy_tree_r() but do not copy SAVE_EXPR or TARGET_EXPR nodes. + These nodes model computations that should only be done once. If we + were to unshare something like SAVE_EXPR(i++), the gimplification + process would create wrong code. */ + +static tree +mostly_copy_tree_r (tree *tp, int *walk_subtrees, void *data) +{ + enum tree_code code = TREE_CODE (*tp); + /* Don't unshare types, decls, constants and SAVE_EXPR nodes. */ + if (TREE_CODE_CLASS (code) == tcc_type + || TREE_CODE_CLASS (code) == tcc_declaration + || TREE_CODE_CLASS (code) == tcc_constant + || code == SAVE_EXPR || code == TARGET_EXPR + /* We can't do anything sensible with a BLOCK used as an expression, + but we also can't just die when we see it because of non-expression + uses. So just avert our eyes and cross our fingers. Silly Java. */ + || code == BLOCK) + *walk_subtrees = 0; + else + { + gcc_assert (code != BIND_EXPR); + copy_tree_r (tp, walk_subtrees, data); + } + + return NULL_TREE; +} + +/* Callback for walk_tree to unshare most of the shared trees rooted at + *TP. If *TP has been visited already (i.e., TREE_VISITED (*TP) == 1), + then *TP is deep copied by calling copy_tree_r. + + This unshares the same trees as copy_tree_r with the exception of + SAVE_EXPR nodes. These nodes model computations that should only be + done once. If we were to unshare something like SAVE_EXPR(i++), the + gimplification process would create wrong code. */ + +static tree +copy_if_shared_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, + void *data ATTRIBUTE_UNUSED) +{ + tree t = *tp; + enum tree_code code = TREE_CODE (t); + + /* Skip types, decls, and constants. But we do want to look at their + types and the bounds of types. Mark them as visited so we properly + unmark their subtrees on the unmark pass. If we've already seen them, + don't look down further. */ + if (TREE_CODE_CLASS (code) == tcc_type + || TREE_CODE_CLASS (code) == tcc_declaration + || TREE_CODE_CLASS (code) == tcc_constant) + { + if (TREE_VISITED (t)) + *walk_subtrees = 0; + else + TREE_VISITED (t) = 1; + } + + /* If this node has been visited already, unshare it and don't look + any deeper. */ + else if (TREE_VISITED (t)) + { + walk_tree (tp, mostly_copy_tree_r, NULL, NULL); + *walk_subtrees = 0; + } + + /* Otherwise, mark the tree as visited and keep looking. */ + else + TREE_VISITED (t) = 1; + + return NULL_TREE; +} + +static tree +unmark_visited_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, + void *data ATTRIBUTE_UNUSED) +{ + if (TREE_VISITED (*tp)) + TREE_VISITED (*tp) = 0; + else + *walk_subtrees = 0; + + return NULL_TREE; +} + +/* Unshare all the trees in BODY_P, a pointer into the body of FNDECL, and the + bodies of any nested functions if we are unsharing the entire body of + FNDECL. */ + +static void +unshare_body (tree *body_p, tree fndecl) +{ + struct cgraph_node *cgn = cgraph_node (fndecl); + + walk_tree (body_p, copy_if_shared_r, NULL, NULL); + if (body_p == &DECL_SAVED_TREE (fndecl)) + for (cgn = cgn->nested; cgn; cgn = cgn->next_nested) + unshare_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl); +} + +/* Likewise, but mark all trees as not visited. */ + +static void +unvisit_body (tree *body_p, tree fndecl) +{ + struct cgraph_node *cgn = cgraph_node (fndecl); + + walk_tree (body_p, unmark_visited_r, NULL, NULL); + if (body_p == &DECL_SAVED_TREE (fndecl)) + for (cgn = cgn->nested; cgn; cgn = cgn->next_nested) + unvisit_body (&DECL_SAVED_TREE (cgn->decl), cgn->decl); +} + +/* Unshare T and all the trees reached from T via TREE_CHAIN. */ + +static void +unshare_all_trees (tree t) +{ + walk_tree (&t, copy_if_shared_r, NULL, NULL); + walk_tree (&t, unmark_visited_r, NULL, NULL); +} + +/* Unconditionally make an unshared copy of EXPR. This is used when using + stored expressions which span multiple functions, such as BINFO_VTABLE, + as the normal unsharing process can't tell that they're shared. */ + +tree +unshare_expr (tree expr) +{ + walk_tree (&expr, mostly_copy_tree_r, NULL, NULL); + return expr; +} + +/* A terser interface for building a representation of an exception + specification. */ + +tree +gimple_build_eh_filter (tree body, tree allowed, tree failure) +{ + tree t; + + /* FIXME should the allowed types go in TREE_TYPE? */ + t = build2 (EH_FILTER_EXPR, void_type_node, allowed, NULL_TREE); + append_to_statement_list (failure, &EH_FILTER_FAILURE (t)); + + t = build2 (TRY_CATCH_EXPR, void_type_node, NULL_TREE, t); + append_to_statement_list (body, &TREE_OPERAND (t, 0)); + + return t; +} + + +/* WRAPPER is a code such as BIND_EXPR or CLEANUP_POINT_EXPR which can both + contain statements and have a value. Assign its value to a temporary + and give it void_type_node. Returns the temporary, or NULL_TREE if + WRAPPER was already void. */ + +tree +voidify_wrapper_expr (tree wrapper, tree temp) +{ + tree type = TREE_TYPE (wrapper); + if (type && !VOID_TYPE_P (type)) + { + tree *p; + + /* Set p to point to the body of the wrapper. Loop until we find + something that isn't a wrapper. */ + for (p = &wrapper; p && *p; ) + { + switch (TREE_CODE (*p)) + { + case BIND_EXPR: + TREE_SIDE_EFFECTS (*p) = 1; + TREE_TYPE (*p) = void_type_node; + /* For a BIND_EXPR, the body is operand 1. */ + p = &BIND_EXPR_BODY (*p); + break; + + case CLEANUP_POINT_EXPR: + case TRY_FINALLY_EXPR: + case TRY_CATCH_EXPR: + TREE_SIDE_EFFECTS (*p) = 1; + TREE_TYPE (*p) = void_type_node; + p = &TREE_OPERAND (*p, 0); + break; + + case STATEMENT_LIST: + { + tree_stmt_iterator i = tsi_last (*p); + TREE_SIDE_EFFECTS (*p) = 1; + TREE_TYPE (*p) = void_type_node; + p = tsi_end_p (i) ? NULL : tsi_stmt_ptr (i); + } + break; + + case COMPOUND_EXPR: + /* Advance to the last statement. Set all container types to void. */ + for (; TREE_CODE (*p) == COMPOUND_EXPR; p = &TREE_OPERAND (*p, 1)) + { + TREE_SIDE_EFFECTS (*p) = 1; + TREE_TYPE (*p) = void_type_node; + } + break; + + default: + goto out; + } + } + + out: + if (p == NULL || IS_EMPTY_STMT (*p)) + temp = NULL_TREE; + else if (temp) + { + /* The wrapper is on the RHS of an assignment that we're pushing + down. */ + gcc_assert (TREE_CODE (temp) == INIT_EXPR + || TREE_CODE (temp) == MODIFY_EXPR); + TREE_OPERAND (temp, 1) = *p; + *p = temp; + } + else + { + temp = create_tmp_var (type, "retval"); + *p = build2 (INIT_EXPR, type, temp, *p); + } + + return temp; + } + + return NULL_TREE; +} + +/* Prepare calls to builtins to SAVE and RESTORE the stack as well as + a temporary through which they communicate. */ + +static void +build_stack_save_restore (tree *save, tree *restore) +{ + tree save_call, tmp_var; + + save_call = + build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_SAVE], + NULL_TREE); + tmp_var = create_tmp_var (ptr_type_node, "saved_stack"); + + *save = build2 (MODIFY_EXPR, ptr_type_node, tmp_var, save_call); + *restore = + build_function_call_expr (implicit_built_in_decls[BUILT_IN_STACK_RESTORE], + tree_cons (NULL_TREE, tmp_var, NULL_TREE)); +} + +/* Gimplify a BIND_EXPR. Just voidify and recurse. */ + +static enum gimplify_status +gimplify_bind_expr (tree *expr_p, tree *pre_p) +{ + tree bind_expr = *expr_p; + bool old_save_stack = gimplify_ctxp->save_stack; + tree t; + + tree temp = voidify_wrapper_expr (bind_expr, NULL); + + /* Mark variables seen in this bind expr. */ + for (t = BIND_EXPR_VARS (bind_expr); t ; t = TREE_CHAIN (t)) + { + if (TREE_CODE (t) == VAR_DECL) + { + struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp; + + /* Mark variable as local. */ + if (ctx && !is_global_var (t) + && (! DECL_SEEN_IN_BIND_EXPR_P (t) + || splay_tree_lookup (ctx->variables, + (splay_tree_key) t) == NULL)) + omp_add_variable (gimplify_omp_ctxp, t, GOVD_LOCAL | GOVD_SEEN); + + DECL_SEEN_IN_BIND_EXPR_P (t) = 1; + } + + /* Preliminarily mark non-addressed complex variables as eligible + for promotion to gimple registers. We'll transform their uses + as we find them. */ + if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE + && !TREE_THIS_VOLATILE (t) + && (TREE_CODE (t) == VAR_DECL && !DECL_HARD_REGISTER (t)) + && !needs_to_live_in_memory (t)) + DECL_COMPLEX_GIMPLE_REG_P (t) = 1; + } + + gimple_push_bind_expr (bind_expr); + gimplify_ctxp->save_stack = false; + + gimplify_to_stmt_list (&BIND_EXPR_BODY (bind_expr)); + + if (gimplify_ctxp->save_stack) + { + tree stack_save, stack_restore; + + /* Save stack on entry and restore it on exit. Add a try_finally + block to achieve this. Note that mudflap depends on the + format of the emitted code: see mx_register_decls(). */ + build_stack_save_restore (&stack_save, &stack_restore); + + t = build2 (TRY_FINALLY_EXPR, void_type_node, + BIND_EXPR_BODY (bind_expr), NULL_TREE); + append_to_statement_list (stack_restore, &TREE_OPERAND (t, 1)); + + BIND_EXPR_BODY (bind_expr) = NULL_TREE; + append_to_statement_list (stack_save, &BIND_EXPR_BODY (bind_expr)); + append_to_statement_list (t, &BIND_EXPR_BODY (bind_expr)); + } + + gimplify_ctxp->save_stack = old_save_stack; + gimple_pop_bind_expr (); + + if (temp) + { + *expr_p = temp; + append_to_statement_list (bind_expr, pre_p); + return GS_OK; + } + else + return GS_ALL_DONE; +} + +/* Gimplify a RETURN_EXPR. If the expression to be returned is not a + GIMPLE value, it is assigned to a new temporary and the statement is + re-written to return the temporary. + + PRE_P points to the list where side effects that must happen before + STMT should be stored. */ + +static enum gimplify_status +gimplify_return_expr (tree stmt, tree *pre_p) +{ + tree ret_expr = TREE_OPERAND (stmt, 0); + tree result_decl, result; + + if (!ret_expr || TREE_CODE (ret_expr) == RESULT_DECL + || ret_expr == error_mark_node) + return GS_ALL_DONE; + + if (VOID_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl)))) + result_decl = NULL_TREE; + else + { + result_decl = TREE_OPERAND (ret_expr, 0); + if (TREE_CODE (result_decl) == INDIRECT_REF) + /* See through a return by reference. */ + result_decl = TREE_OPERAND (result_decl, 0); + + gcc_assert ((TREE_CODE (ret_expr) == MODIFY_EXPR + || TREE_CODE (ret_expr) == INIT_EXPR) + && TREE_CODE (result_decl) == RESULT_DECL); + } + + /* If aggregate_value_p is true, then we can return the bare RESULT_DECL. + Recall that aggregate_value_p is FALSE for any aggregate type that is + returned in registers. If we're returning values in registers, then + we don't want to extend the lifetime of the RESULT_DECL, particularly + across another call. In addition, for those aggregates for which + hard_function_value generates a PARALLEL, we'll die during normal + expansion of structure assignments; there's special code in expand_return + to handle this case that does not exist in expand_expr. */ + if (!result_decl + || aggregate_value_p (result_decl, TREE_TYPE (current_function_decl))) + result = result_decl; + else if (gimplify_ctxp->return_temp) + result = gimplify_ctxp->return_temp; + else + { + result = create_tmp_var (TREE_TYPE (result_decl), NULL); + + /* ??? With complex control flow (usually involving abnormal edges), + we can wind up warning about an uninitialized value for this. Due + to how this variable is constructed and initialized, this is never + true. Give up and never warn. */ + TREE_NO_WARNING (result) = 1; + + gimplify_ctxp->return_temp = result; + } + + /* Smash the lhs of the MODIFY_EXPR to the temporary we plan to use. + Then gimplify the whole thing. */ + if (result != result_decl) + TREE_OPERAND (ret_expr, 0) = result; + + gimplify_and_add (TREE_OPERAND (stmt, 0), pre_p); + + /* If we didn't use a temporary, then the result is just the result_decl. + Otherwise we need a simple copy. This should already be gimple. */ + if (result == result_decl) + ret_expr = result; + else + ret_expr = build2 (MODIFY_EXPR, TREE_TYPE (result), result_decl, result); + TREE_OPERAND (stmt, 0) = ret_expr; + + return GS_ALL_DONE; +} + +/* Gimplifies a DECL_EXPR node *STMT_P by making any necessary allocation + and initialization explicit. */ + +static enum gimplify_status +gimplify_decl_expr (tree *stmt_p) +{ + tree stmt = *stmt_p; + tree decl = DECL_EXPR_DECL (stmt); + + *stmt_p = NULL_TREE; + + if (TREE_TYPE (decl) == error_mark_node) + return GS_ERROR; + + if ((TREE_CODE (decl) == TYPE_DECL + || TREE_CODE (decl) == VAR_DECL) + && !TYPE_SIZES_GIMPLIFIED (TREE_TYPE (decl))) + gimplify_type_sizes (TREE_TYPE (decl), stmt_p); + + if (TREE_CODE (decl) == VAR_DECL && !DECL_EXTERNAL (decl)) + { + tree init = DECL_INITIAL (decl); + + if (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) + { + /* This is a variable-sized decl. Simplify its size and mark it + for deferred expansion. Note that mudflap depends on the format + of the emitted code: see mx_register_decls(). */ + tree t, args, addr, ptr_type; + + gimplify_one_sizepos (&DECL_SIZE (decl), stmt_p); + gimplify_one_sizepos (&DECL_SIZE_UNIT (decl), stmt_p); + + /* All occurrences of this decl in final gimplified code will be + replaced by indirection. Setting DECL_VALUE_EXPR does two + things: First, it lets the rest of the gimplifier know what + replacement to use. Second, it lets the debug info know + where to find the value. */ + ptr_type = build_pointer_type (TREE_TYPE (decl)); + addr = create_tmp_var (ptr_type, get_name (decl)); + DECL_IGNORED_P (addr) = 0; + t = build_fold_indirect_ref (addr); + SET_DECL_VALUE_EXPR (decl, t); + DECL_HAS_VALUE_EXPR_P (decl) = 1; + + args = tree_cons (NULL, DECL_SIZE_UNIT (decl), NULL); + t = built_in_decls[BUILT_IN_ALLOCA]; + t = build_function_call_expr (t, args); + t = fold_convert (ptr_type, t); + t = build2 (MODIFY_EXPR, void_type_node, addr, t); + + gimplify_and_add (t, stmt_p); + + /* Indicate that we need to restore the stack level when the + enclosing BIND_EXPR is exited. */ + gimplify_ctxp->save_stack = true; + } + + if (init && init != error_mark_node) + { + if (!TREE_STATIC (decl)) + { + DECL_INITIAL (decl) = NULL_TREE; + init = build2 (INIT_EXPR, void_type_node, decl, init); + gimplify_and_add (init, stmt_p); + } + else + /* We must still examine initializers for static variables + as they may contain a label address. */ + walk_tree (&init, force_labels_r, NULL, NULL); + } + + /* Some front ends do not explicitly declare all anonymous + artificial variables. We compensate here by declaring the + variables, though it would be better if the front ends would + explicitly declare them. */ + if (!DECL_SEEN_IN_BIND_EXPR_P (decl) + && DECL_ARTIFICIAL (decl) && DECL_NAME (decl) == NULL_TREE) + gimple_add_tmp_var (decl); + } + + return GS_ALL_DONE; +} + +/* Gimplify a LOOP_EXPR. Normally this just involves gimplifying the body + and replacing the LOOP_EXPR with goto, but if the loop contains an + EXIT_EXPR, we need to append a label for it to jump to. */ + +static enum gimplify_status +gimplify_loop_expr (tree *expr_p, tree *pre_p) +{ + tree saved_label = gimplify_ctxp->exit_label; + tree start_label = build1 (LABEL_EXPR, void_type_node, NULL_TREE); + tree jump_stmt = build_and_jump (&LABEL_EXPR_LABEL (start_label)); + + append_to_statement_list (start_label, pre_p); + + gimplify_ctxp->exit_label = NULL_TREE; + + gimplify_and_add (LOOP_EXPR_BODY (*expr_p), pre_p); + + if (gimplify_ctxp->exit_label) + { + append_to_statement_list (jump_stmt, pre_p); + *expr_p = build1 (LABEL_EXPR, void_type_node, gimplify_ctxp->exit_label); + } + else + *expr_p = jump_stmt; + + gimplify_ctxp->exit_label = saved_label; + + return GS_ALL_DONE; +} + +/* Compare two case labels. Because the front end should already have + made sure that case ranges do not overlap, it is enough to only compare + the CASE_LOW values of each case label. */ + +static int +compare_case_labels (const void *p1, const void *p2) +{ + tree case1 = *(tree *)p1; + tree case2 = *(tree *)p2; + + return tree_int_cst_compare (CASE_LOW (case1), CASE_LOW (case2)); +} + +/* Sort the case labels in LABEL_VEC in place in ascending order. */ + +void +sort_case_labels (tree label_vec) +{ + size_t len = TREE_VEC_LENGTH (label_vec); + tree default_case = TREE_VEC_ELT (label_vec, len - 1); + + if (CASE_LOW (default_case)) + { + size_t i; + + /* The last label in the vector should be the default case + but it is not. */ + for (i = 0; i < len; ++i) + { + tree t = TREE_VEC_ELT (label_vec, i); + if (!CASE_LOW (t)) + { + default_case = t; + TREE_VEC_ELT (label_vec, i) = TREE_VEC_ELT (label_vec, len - 1); + TREE_VEC_ELT (label_vec, len - 1) = default_case; + break; + } + } + } + + qsort (&TREE_VEC_ELT (label_vec, 0), len - 1, sizeof (tree), + compare_case_labels); +} + +/* Gimplify a SWITCH_EXPR, and collect a TREE_VEC of the labels it can + branch to. */ + +static enum gimplify_status +gimplify_switch_expr (tree *expr_p, tree *pre_p) +{ + tree switch_expr = *expr_p; + enum gimplify_status ret; + + ret = gimplify_expr (&SWITCH_COND (switch_expr), pre_p, NULL, + is_gimple_val, fb_rvalue); + + if (SWITCH_BODY (switch_expr)) + { + VEC(tree,heap) *labels, *saved_labels; + tree label_vec, default_case = NULL_TREE; + size_t i, len; + + /* If someone can be bothered to fill in the labels, they can + be bothered to null out the body too. */ + gcc_assert (!SWITCH_LABELS (switch_expr)); + + saved_labels = gimplify_ctxp->case_labels; + gimplify_ctxp->case_labels = VEC_alloc (tree, heap, 8); + + gimplify_to_stmt_list (&SWITCH_BODY (switch_expr)); + + labels = gimplify_ctxp->case_labels; + gimplify_ctxp->case_labels = saved_labels; + + i = 0; + while (i < VEC_length (tree, labels)) + { + tree elt = VEC_index (tree, labels, i); + tree low = CASE_LOW (elt); + bool remove_element = FALSE; + + if (low) + { + /* Discard empty ranges. */ + tree high = CASE_HIGH (elt); + if (high && INT_CST_LT (high, low)) + remove_element = TRUE; + } + else + { + /* The default case must be the last label in the list. */ + gcc_assert (!default_case); + default_case = elt; + remove_element = TRUE; + } + + if (remove_element) + VEC_ordered_remove (tree, labels, i); + else + i++; + } + len = i; + + label_vec = make_tree_vec (len + 1); + SWITCH_LABELS (*expr_p) = label_vec; + append_to_statement_list (switch_expr, pre_p); + + if (! default_case) + { + /* If the switch has no default label, add one, so that we jump + around the switch body. */ + default_case = build3 (CASE_LABEL_EXPR, void_type_node, NULL_TREE, + NULL_TREE, create_artificial_label ()); + append_to_statement_list (SWITCH_BODY (switch_expr), pre_p); + *expr_p = build1 (LABEL_EXPR, void_type_node, + CASE_LABEL (default_case)); + } + else + *expr_p = SWITCH_BODY (switch_expr); + + for (i = 0; i < len; ++i) + TREE_VEC_ELT (label_vec, i) = VEC_index (tree, labels, i); + TREE_VEC_ELT (label_vec, len) = default_case; + + VEC_free (tree, heap, labels); + + sort_case_labels (label_vec); + + SWITCH_BODY (switch_expr) = NULL; + } + else + gcc_assert (SWITCH_LABELS (switch_expr)); + + return ret; +} + +static enum gimplify_status +gimplify_case_label_expr (tree *expr_p) +{ + tree expr = *expr_p; + struct gimplify_ctx *ctxp; + + /* Invalid OpenMP programs can play Duff's Device type games with + #pragma omp parallel. At least in the C front end, we don't + detect such invalid branches until after gimplification. */ + for (ctxp = gimplify_ctxp; ; ctxp = ctxp->prev_context) + if (ctxp->case_labels) + break; + + VEC_safe_push (tree, heap, ctxp->case_labels, expr); + *expr_p = build1 (LABEL_EXPR, void_type_node, CASE_LABEL (expr)); + return GS_ALL_DONE; +} + +/* Build a GOTO to the LABEL_DECL pointed to by LABEL_P, building it first + if necessary. */ + +tree +build_and_jump (tree *label_p) +{ + if (label_p == NULL) + /* If there's nowhere to jump, just fall through. */ + return NULL_TREE; + + if (*label_p == NULL_TREE) + { + tree label = create_artificial_label (); + *label_p = label; + } + + return build1 (GOTO_EXPR, void_type_node, *label_p); +} + +/* Gimplify an EXIT_EXPR by converting to a GOTO_EXPR inside a COND_EXPR. + This also involves building a label to jump to and communicating it to + gimplify_loop_expr through gimplify_ctxp->exit_label. */ + +static enum gimplify_status +gimplify_exit_expr (tree *expr_p) +{ + tree cond = TREE_OPERAND (*expr_p, 0); + tree expr; + + expr = build_and_jump (&gimplify_ctxp->exit_label); + expr = build3 (COND_EXPR, void_type_node, cond, expr, NULL_TREE); + *expr_p = expr; + + return GS_OK; +} + +/* A helper function to be called via walk_tree. Mark all labels under *TP + as being forced. To be called for DECL_INITIAL of static variables. */ + +tree +force_labels_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED) +{ + if (TYPE_P (*tp)) + *walk_subtrees = 0; + if (TREE_CODE (*tp) == LABEL_DECL) + FORCED_LABEL (*tp) = 1; + + return NULL_TREE; +} + +/* *EXPR_P is a COMPONENT_REF being used as an rvalue. If its type is + different from its canonical type, wrap the whole thing inside a + NOP_EXPR and force the type of the COMPONENT_REF to be the canonical + type. + + The canonical type of a COMPONENT_REF is the type of the field being + referenced--unless the field is a bit-field which can be read directly + in a smaller mode, in which case the canonical type is the + sign-appropriate type corresponding to that mode. */ + +static void +canonicalize_component_ref (tree *expr_p) +{ + tree expr = *expr_p; + tree type; + + gcc_assert (TREE_CODE (expr) == COMPONENT_REF); + + if (INTEGRAL_TYPE_P (TREE_TYPE (expr))) + type = TREE_TYPE (get_unwidened (expr, NULL_TREE)); + else + type = TREE_TYPE (TREE_OPERAND (expr, 1)); + + if (TREE_TYPE (expr) != type) + { + tree old_type = TREE_TYPE (expr); + + /* Set the type of the COMPONENT_REF to the underlying type. */ + TREE_TYPE (expr) = type; + + /* And wrap the whole thing inside a NOP_EXPR. */ + expr = build1 (NOP_EXPR, old_type, expr); + + *expr_p = expr; + } +} + +/* If a NOP conversion is changing a pointer to array of foo to a pointer + to foo, embed that change in the ADDR_EXPR by converting + T array[U]; + (T *)&array + ==> + &array[L] + where L is the lower bound. For simplicity, only do this for constant + lower bound. */ + +static void +canonicalize_addr_expr (tree *expr_p) +{ + tree expr = *expr_p; + tree ctype = TREE_TYPE (expr); + tree addr_expr = TREE_OPERAND (expr, 0); + tree atype = TREE_TYPE (addr_expr); + tree dctype, datype, ddatype, otype, obj_expr; + + /* Both cast and addr_expr types should be pointers. */ + if (!POINTER_TYPE_P (ctype) || !POINTER_TYPE_P (atype)) + return; + + /* The addr_expr type should be a pointer to an array. */ + datype = TREE_TYPE (atype); + if (TREE_CODE (datype) != ARRAY_TYPE) + return; + + /* Both cast and addr_expr types should address the same object type. */ + dctype = TREE_TYPE (ctype); + ddatype = TREE_TYPE (datype); + if (!lang_hooks.types_compatible_p (ddatype, dctype)) + return; + + /* The addr_expr and the object type should match. */ + obj_expr = TREE_OPERAND (addr_expr, 0); + otype = TREE_TYPE (obj_expr); + if (!lang_hooks.types_compatible_p (otype, datype)) + return; + + /* The lower bound and element sizes must be constant. */ + if (!TYPE_SIZE_UNIT (dctype) + || TREE_CODE (TYPE_SIZE_UNIT (dctype)) != INTEGER_CST + || !TYPE_DOMAIN (datype) || !TYPE_MIN_VALUE (TYPE_DOMAIN (datype)) + || TREE_CODE (TYPE_MIN_VALUE (TYPE_DOMAIN (datype))) != INTEGER_CST) + return; + + /* All checks succeeded. Build a new node to merge the cast. */ + *expr_p = build4 (ARRAY_REF, dctype, obj_expr, + TYPE_MIN_VALUE (TYPE_DOMAIN (datype)), + TYPE_MIN_VALUE (TYPE_DOMAIN (datype)), + size_binop (EXACT_DIV_EXPR, TYPE_SIZE_UNIT (dctype), + size_int (TYPE_ALIGN_UNIT (dctype)))); + *expr_p = build1 (ADDR_EXPR, ctype, *expr_p); +} + +/* *EXPR_P is a NOP_EXPR or CONVERT_EXPR. Remove it and/or other conversions + underneath as appropriate. */ + +static enum gimplify_status +gimplify_conversion (tree *expr_p) +{ + gcc_assert (TREE_CODE (*expr_p) == NOP_EXPR + || TREE_CODE (*expr_p) == CONVERT_EXPR); + + /* Then strip away all but the outermost conversion. */ + STRIP_SIGN_NOPS (TREE_OPERAND (*expr_p, 0)); + + /* And remove the outermost conversion if it's useless. */ + if (tree_ssa_useless_type_conversion (*expr_p)) + *expr_p = TREE_OPERAND (*expr_p, 0); + + /* If we still have a conversion at the toplevel, + then canonicalize some constructs. */ + if (TREE_CODE (*expr_p) == NOP_EXPR || TREE_CODE (*expr_p) == CONVERT_EXPR) + { + tree sub = TREE_OPERAND (*expr_p, 0); + + /* If a NOP conversion is changing the type of a COMPONENT_REF + expression, then canonicalize its type now in order to expose more + redundant conversions. */ + if (TREE_CODE (sub) == COMPONENT_REF) + canonicalize_component_ref (&TREE_OPERAND (*expr_p, 0)); + + /* If a NOP conversion is changing a pointer to array of foo + to a pointer to foo, embed that change in the ADDR_EXPR. */ + else if (TREE_CODE (sub) == ADDR_EXPR) + canonicalize_addr_expr (expr_p); + } + + return GS_OK; +} + +/* Gimplify a VAR_DECL or PARM_DECL. Returns GS_OK if we expanded a + DECL_VALUE_EXPR, and it's worth re-examining things. */ + +static enum gimplify_status +gimplify_var_or_parm_decl (tree *expr_p) +{ + tree decl = *expr_p; + + /* ??? If this is a local variable, and it has not been seen in any + outer BIND_EXPR, then it's probably the result of a duplicate + declaration, for which we've already issued an error. It would + be really nice if the front end wouldn't leak these at all. + Currently the only known culprit is C++ destructors, as seen + in g++.old-deja/g++.jason/binding.C. */ + if (TREE_CODE (decl) == VAR_DECL + && !DECL_SEEN_IN_BIND_EXPR_P (decl) + && !TREE_STATIC (decl) && !DECL_EXTERNAL (decl) + && decl_function_context (decl) == current_function_decl) + { + gcc_assert (errorcount || sorrycount); + return GS_ERROR; + } + + /* When within an OpenMP context, notice uses of variables. */ + if (gimplify_omp_ctxp && omp_notice_variable (gimplify_omp_ctxp, decl, true)) + return GS_ALL_DONE; + + /* If the decl is an alias for another expression, substitute it now. */ + if (DECL_HAS_VALUE_EXPR_P (decl)) + { + *expr_p = unshare_expr (DECL_VALUE_EXPR (decl)); + return GS_OK; + } + + return GS_ALL_DONE; +} + + +/* Gimplify the COMPONENT_REF, ARRAY_REF, REALPART_EXPR or IMAGPART_EXPR + node pointed to by EXPR_P. + + compound_lval + : min_lval '[' val ']' + | min_lval '.' ID + | compound_lval '[' val ']' + | compound_lval '.' ID + + This is not part of the original SIMPLE definition, which separates + array and member references, but it seems reasonable to handle them + together. Also, this way we don't run into problems with union + aliasing; gcc requires that for accesses through a union to alias, the + union reference must be explicit, which was not always the case when we + were splitting up array and member refs. + + PRE_P points to the list where side effects that must happen before + *EXPR_P should be stored. + + POST_P points to the list where side effects that must happen after + *EXPR_P should be stored. */ + +static enum gimplify_status +gimplify_compound_lval (tree *expr_p, tree *pre_p, + tree *post_p, fallback_t fallback) +{ + tree *p; + VEC(tree,heap) *stack; + enum gimplify_status ret = GS_OK, tret; + int i; + + /* Create a stack of the subexpressions so later we can walk them in + order from inner to outer. */ + stack = VEC_alloc (tree, heap, 10); + + /* We can handle anything that get_inner_reference can deal with. */ + for (p = expr_p; ; p = &TREE_OPERAND (*p, 0)) + { + restart: + /* Fold INDIRECT_REFs now to turn them into ARRAY_REFs. */ + if (TREE_CODE (*p) == INDIRECT_REF) + *p = fold_indirect_ref (*p); + + if (handled_component_p (*p)) + ; + /* Expand DECL_VALUE_EXPR now. In some cases that may expose + additional COMPONENT_REFs. */ + else if ((TREE_CODE (*p) == VAR_DECL || TREE_CODE (*p) == PARM_DECL) + && gimplify_var_or_parm_decl (p) == GS_OK) + goto restart; + else + break; + + VEC_safe_push (tree, heap, stack, *p); + } + + gcc_assert (VEC_length (tree, stack)); + + /* Now STACK is a stack of pointers to all the refs we've walked through + and P points to the innermost expression. + + Java requires that we elaborated nodes in source order. That + means we must gimplify the inner expression followed by each of + the indices, in order. But we can't gimplify the inner + expression until we deal with any variable bounds, sizes, or + positions in order to deal with PLACEHOLDER_EXPRs. + + So we do this in three steps. First we deal with the annotations + for any variables in the components, then we gimplify the base, + then we gimplify any indices, from left to right. */ + for (i = VEC_length (tree, stack) - 1; i >= 0; i--) + { + tree t = VEC_index (tree, stack, i); + + if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) + { + /* Gimplify the low bound and element type size and put them into + the ARRAY_REF. If these values are set, they have already been + gimplified. */ + if (!TREE_OPERAND (t, 2)) + { + tree low = unshare_expr (array_ref_low_bound (t)); + if (!is_gimple_min_invariant (low)) + { + TREE_OPERAND (t, 2) = low; + tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p, + is_gimple_formal_tmp_reg, fb_rvalue); + ret = MIN (ret, tret); + } + } + + if (!TREE_OPERAND (t, 3)) + { + tree elmt_type = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0))); + tree elmt_size = unshare_expr (array_ref_element_size (t)); + tree factor = size_int (TYPE_ALIGN_UNIT (elmt_type)); + + /* Divide the element size by the alignment of the element + type (above). */ + elmt_size = size_binop (EXACT_DIV_EXPR, elmt_size, factor); + + if (!is_gimple_min_invariant (elmt_size)) + { + TREE_OPERAND (t, 3) = elmt_size; + tret = gimplify_expr (&TREE_OPERAND (t, 3), pre_p, post_p, + is_gimple_formal_tmp_reg, fb_rvalue); + ret = MIN (ret, tret); + } + } + } + else if (TREE_CODE (t) == COMPONENT_REF) + { + /* Set the field offset into T and gimplify it. */ + if (!TREE_OPERAND (t, 2)) + { + tree offset = unshare_expr (component_ref_field_offset (t)); + tree field = TREE_OPERAND (t, 1); + tree factor + = size_int (DECL_OFFSET_ALIGN (field) / BITS_PER_UNIT); + + /* Divide the offset by its alignment. */ + offset = size_binop (EXACT_DIV_EXPR, offset, factor); + + if (!is_gimple_min_invariant (offset)) + { + TREE_OPERAND (t, 2) = offset; + tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p, + is_gimple_formal_tmp_reg, fb_rvalue); + ret = MIN (ret, tret); + } + } + } + } + + /* Step 2 is to gimplify the base expression. Make sure lvalue is set + so as to match the min_lval predicate. Failure to do so may result + in the creation of large aggregate temporaries. */ + tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, + fallback | fb_lvalue); + ret = MIN (ret, tret); + + /* And finally, the indices and operands to BIT_FIELD_REF. During this + loop we also remove any useless conversions. */ + for (; VEC_length (tree, stack) > 0; ) + { + tree t = VEC_pop (tree, stack); + + if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) + { + /* Gimplify the dimension. + Temporary fix for gcc.c-torture/execute/20040313-1.c. + Gimplify non-constant array indices into a temporary + variable. + FIXME - The real fix is to gimplify post-modify + expressions into a minimal gimple lvalue. However, that + exposes bugs in alias analysis. The alias analyzer does + not handle &PTR->FIELD very well. Will fix after the + branch is merged into mainline (dnovillo 2004-05-03). */ + if (!is_gimple_min_invariant (TREE_OPERAND (t, 1))) + { + tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p, + is_gimple_formal_tmp_reg, fb_rvalue); + ret = MIN (ret, tret); + } + } + else if (TREE_CODE (t) == BIT_FIELD_REF) + { + tret = gimplify_expr (&TREE_OPERAND (t, 1), pre_p, post_p, + is_gimple_val, fb_rvalue); + ret = MIN (ret, tret); + tret = gimplify_expr (&TREE_OPERAND (t, 2), pre_p, post_p, + is_gimple_val, fb_rvalue); + ret = MIN (ret, tret); + } + + STRIP_USELESS_TYPE_CONVERSION (TREE_OPERAND (t, 0)); + + /* The innermost expression P may have originally had TREE_SIDE_EFFECTS + set which would have caused all the outer expressions in EXPR_P + leading to P to also have had TREE_SIDE_EFFECTS set. */ + recalculate_side_effects (t); + } + + tret = gimplify_expr (p, pre_p, post_p, is_gimple_min_lval, fallback); + ret = MIN (ret, tret); + + /* If the outermost expression is a COMPONENT_REF, canonicalize its type. */ + if ((fallback & fb_rvalue) && TREE_CODE (*expr_p) == COMPONENT_REF) + { + canonicalize_component_ref (expr_p); + ret = MIN (ret, GS_OK); + } + + VEC_free (tree, heap, stack); + + return ret; +} + +/* Gimplify the self modifying expression pointed to by EXPR_P + (++, --, +=, -=). + + PRE_P points to the list where side effects that must happen before + *EXPR_P should be stored. + + POST_P points to the list where side effects that must happen after + *EXPR_P should be stored. + + WANT_VALUE is nonzero iff we want to use the value of this expression + in another expression. */ + +static enum gimplify_status +gimplify_self_mod_expr (tree *expr_p, tree *pre_p, tree *post_p, + bool want_value) +{ + enum tree_code code; + tree lhs, lvalue, rhs, t1, post = NULL, *orig_post_p = post_p; + bool postfix; + enum tree_code arith_code; + enum gimplify_status ret; + + code = TREE_CODE (*expr_p); + + gcc_assert (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR + || code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR); + + /* Prefix or postfix? */ + if (code == POSTINCREMENT_EXPR || code == POSTDECREMENT_EXPR) + /* Faster to treat as prefix if result is not used. */ + postfix = want_value; + else + postfix = false; + + /* For postfix, make sure the inner expression's post side effects + are executed after side effects from this expression. */ + if (postfix) + post_p = &post; + + /* Add or subtract? */ + if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR) + arith_code = PLUS_EXPR; + else + arith_code = MINUS_EXPR; + + /* Gimplify the LHS into a GIMPLE lvalue. */ + lvalue = TREE_OPERAND (*expr_p, 0); + ret = gimplify_expr (&lvalue, pre_p, post_p, is_gimple_lvalue, fb_lvalue); + if (ret == GS_ERROR) + return ret; + + /* Extract the operands to the arithmetic operation. */ + lhs = lvalue; + rhs = TREE_OPERAND (*expr_p, 1); + + /* For postfix operator, we evaluate the LHS to an rvalue and then use + that as the result value and in the postqueue operation. */ + if (postfix) + { + ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue); + if (ret == GS_ERROR) + return ret; + } + + t1 = build2 (arith_code, TREE_TYPE (*expr_p), lhs, rhs); + t1 = build2 (MODIFY_EXPR, TREE_TYPE (lvalue), lvalue, t1); + + if (postfix) + { + gimplify_and_add (t1, orig_post_p); + append_to_statement_list (post, orig_post_p); + *expr_p = lhs; + return GS_ALL_DONE; + } + else + { + *expr_p = t1; + return GS_OK; + } +} + +/* If *EXPR_P has a variable sized type, wrap it in a WITH_SIZE_EXPR. */ + +static void +maybe_with_size_expr (tree *expr_p) +{ + tree expr = *expr_p; + tree type = TREE_TYPE (expr); + tree size; + + /* If we've already wrapped this or the type is error_mark_node, we can't do + anything. */ + if (TREE_CODE (expr) == WITH_SIZE_EXPR + || type == error_mark_node) + return; + + /* If the size isn't known or is a constant, we have nothing to do. */ + size = TYPE_SIZE_UNIT (type); + if (!size || TREE_CODE (size) == INTEGER_CST) + return; + + /* Otherwise, make a WITH_SIZE_EXPR. */ + size = unshare_expr (size); + size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, expr); + *expr_p = build2 (WITH_SIZE_EXPR, type, expr, size); +} + +/* Subroutine of gimplify_call_expr: Gimplify a single argument. */ + +static enum gimplify_status +gimplify_arg (tree *expr_p, tree *pre_p) +{ + bool (*test) (tree); + fallback_t fb; + + /* In general, we allow lvalues for function arguments to avoid + extra overhead of copying large aggregates out of even larger + aggregates into temporaries only to copy the temporaries to + the argument list. Make optimizers happy by pulling out to + temporaries those types that fit in registers. */ + if (is_gimple_reg_type (TREE_TYPE (*expr_p))) + test = is_gimple_val, fb = fb_rvalue; + else + test = is_gimple_lvalue, fb = fb_either; + + /* If this is a variable sized type, we must remember the size. */ + maybe_with_size_expr (expr_p); + + /* There is a sequence point before a function call. Side effects in + the argument list must occur before the actual call. So, when + gimplifying arguments, force gimplify_expr to use an internal + post queue which is then appended to the end of PRE_P. */ + return gimplify_expr (expr_p, pre_p, NULL, test, fb); +} + +/* Gimplify the CALL_EXPR node pointed to by EXPR_P. PRE_P points to the + list where side effects that must happen before *EXPR_P should be stored. + WANT_VALUE is true if the result of the call is desired. */ + +static enum gimplify_status +gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value) +{ + tree decl; + tree arglist; + enum gimplify_status ret; + + gcc_assert (TREE_CODE (*expr_p) == CALL_EXPR); + + /* For reliable diagnostics during inlining, it is necessary that + every call_expr be annotated with file and line. */ + if (! EXPR_HAS_LOCATION (*expr_p)) + SET_EXPR_LOCATION (*expr_p, input_location); + + /* This may be a call to a builtin function. + + Builtin function calls may be transformed into different + (and more efficient) builtin function calls under certain + circumstances. Unfortunately, gimplification can muck things + up enough that the builtin expanders are not aware that certain + transformations are still valid. + + So we attempt transformation/gimplification of the call before + we gimplify the CALL_EXPR. At this time we do not manage to + transform all calls in the same manner as the expanders do, but + we do transform most of them. */ + decl = get_callee_fndecl (*expr_p); + if (decl && DECL_BUILT_IN (decl)) + { + tree arglist = TREE_OPERAND (*expr_p, 1); + tree new = fold_builtin (decl, arglist, !want_value); + + if (new && new != *expr_p) + { + /* There was a transformation of this call which computes the + same value, but in a more efficient way. Return and try + again. */ + *expr_p = new; + return GS_OK; + } + + if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL + && DECL_FUNCTION_CODE (decl) == BUILT_IN_VA_START) + { + if (!arglist || !TREE_CHAIN (arglist)) + { + error ("too few arguments to function %<va_start%>"); + *expr_p = build_empty_stmt (); + return GS_OK; + } + + if (fold_builtin_next_arg (TREE_CHAIN (arglist))) + { + *expr_p = build_empty_stmt (); + return GS_OK; + } + /* Avoid gimplifying the second argument to va_start, which needs + to be the plain PARM_DECL. */ + return gimplify_arg (&TREE_VALUE (TREE_OPERAND (*expr_p, 1)), pre_p); + } + } + + /* There is a sequence point before the call, so any side effects in + the calling expression must occur before the actual call. Force + gimplify_expr to use an internal post queue. */ + ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, NULL, + is_gimple_call_addr, fb_rvalue); + + if (PUSH_ARGS_REVERSED) + TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1)); + for (arglist = TREE_OPERAND (*expr_p, 1); arglist; + arglist = TREE_CHAIN (arglist)) + { + enum gimplify_status t; + + t = gimplify_arg (&TREE_VALUE (arglist), pre_p); + + if (t == GS_ERROR) + ret = GS_ERROR; + } + if (PUSH_ARGS_REVERSED) + TREE_OPERAND (*expr_p, 1) = nreverse (TREE_OPERAND (*expr_p, 1)); + + /* Try this again in case gimplification exposed something. */ + if (ret != GS_ERROR) + { + decl = get_callee_fndecl (*expr_p); + if (decl && DECL_BUILT_IN (decl)) + { + tree arglist = TREE_OPERAND (*expr_p, 1); + tree new = fold_builtin (decl, arglist, !want_value); + + if (new && new != *expr_p) + { + /* There was a transformation of this call which computes the + same value, but in a more efficient way. Return and try + again. */ + *expr_p = new; + return GS_OK; + } + } + } + + /* If the function is "const" or "pure", then clear TREE_SIDE_EFFECTS on its + decl. This allows us to eliminate redundant or useless + calls to "const" functions. */ + if (TREE_CODE (*expr_p) == CALL_EXPR + && (call_expr_flags (*expr_p) & (ECF_CONST | ECF_PURE))) + TREE_SIDE_EFFECTS (*expr_p) = 0; + + return ret; +} + +/* Handle shortcut semantics in the predicate operand of a COND_EXPR by + rewriting it into multiple COND_EXPRs, and possibly GOTO_EXPRs. + + TRUE_LABEL_P and FALSE_LABEL_P point to the labels to jump to if the + condition is true or false, respectively. If null, we should generate + our own to skip over the evaluation of this specific expression. + + This function is the tree equivalent of do_jump. + + shortcut_cond_r should only be called by shortcut_cond_expr. */ + +static tree +shortcut_cond_r (tree pred, tree *true_label_p, tree *false_label_p) +{ + tree local_label = NULL_TREE; + tree t, expr = NULL; + + /* OK, it's not a simple case; we need to pull apart the COND_EXPR to + retain the shortcut semantics. Just insert the gotos here; + shortcut_cond_expr will append the real blocks later. */ + if (TREE_CODE (pred) == TRUTH_ANDIF_EXPR) + { + /* Turn if (a && b) into + + if (a); else goto no; + if (b) goto yes; else goto no; + (no:) */ + + if (false_label_p == NULL) + false_label_p = &local_label; + + t = shortcut_cond_r (TREE_OPERAND (pred, 0), NULL, false_label_p); + append_to_statement_list (t, &expr); + + t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p, + false_label_p); + append_to_statement_list (t, &expr); + } + else if (TREE_CODE (pred) == TRUTH_ORIF_EXPR) + { + /* Turn if (a || b) into + + if (a) goto yes; + if (b) goto yes; else goto no; + (yes:) */ + + if (true_label_p == NULL) + true_label_p = &local_label; + + t = shortcut_cond_r (TREE_OPERAND (pred, 0), true_label_p, NULL); + append_to_statement_list (t, &expr); + + t = shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p, + false_label_p); + append_to_statement_list (t, &expr); + } + else if (TREE_CODE (pred) == COND_EXPR) + { + /* As long as we're messing with gotos, turn if (a ? b : c) into + if (a) + if (b) goto yes; else goto no; + else + if (c) goto yes; else goto no; */ + expr = build3 (COND_EXPR, void_type_node, TREE_OPERAND (pred, 0), + shortcut_cond_r (TREE_OPERAND (pred, 1), true_label_p, + false_label_p), + shortcut_cond_r (TREE_OPERAND (pred, 2), true_label_p, + false_label_p)); + } + else + { + expr = build3 (COND_EXPR, void_type_node, pred, + build_and_jump (true_label_p), + build_and_jump (false_label_p)); + } + + if (local_label) + { + t = build1 (LABEL_EXPR, void_type_node, local_label); + append_to_statement_list (t, &expr); + } + + return expr; +} + +static tree +shortcut_cond_expr (tree expr) +{ + tree pred = TREE_OPERAND (expr, 0); + tree then_ = TREE_OPERAND (expr, 1); + tree else_ = TREE_OPERAND (expr, 2); + tree true_label, false_label, end_label, t; + tree *true_label_p; + tree *false_label_p; + bool emit_end, emit_false, jump_over_else; + bool then_se = then_ && TREE_SIDE_EFFECTS (then_); + bool else_se = else_ && TREE_SIDE_EFFECTS (else_); + + /* First do simple transformations. */ + if (!else_se) + { + /* If there is no 'else', turn (a && b) into if (a) if (b). */ + while (TREE_CODE (pred) == TRUTH_ANDIF_EXPR) + { + TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1); + then_ = shortcut_cond_expr (expr); + then_se = then_ && TREE_SIDE_EFFECTS (then_); + pred = TREE_OPERAND (pred, 0); + expr = build3 (COND_EXPR, void_type_node, pred, then_, NULL_TREE); + } + } + if (!then_se) + { + /* If there is no 'then', turn + if (a || b); else d + into + if (a); else if (b); else d. */ + while (TREE_CODE (pred) == TRUTH_ORIF_EXPR) + { + TREE_OPERAND (expr, 0) = TREE_OPERAND (pred, 1); + else_ = shortcut_cond_expr (expr); + else_se = else_ && TREE_SIDE_EFFECTS (else_); + pred = TREE_OPERAND (pred, 0); + expr = build3 (COND_EXPR, void_type_node, pred, NULL_TREE, else_); + } + } + + /* If we're done, great. */ + if (TREE_CODE (pred) != TRUTH_ANDIF_EXPR + && TREE_CODE (pred) != TRUTH_ORIF_EXPR) + return expr; + + /* Otherwise we need to mess with gotos. Change + if (a) c; else d; + to + if (a); else goto no; + c; goto end; + no: d; end: + and recursively gimplify the condition. */ + + true_label = false_label = end_label = NULL_TREE; + + /* If our arms just jump somewhere, hijack those labels so we don't + generate jumps to jumps. */ + + if (then_ + && TREE_CODE (then_) == GOTO_EXPR + && TREE_CODE (GOTO_DESTINATION (then_)) == LABEL_DECL) + { + true_label = GOTO_DESTINATION (then_); + then_ = NULL; + then_se = false; + } + + if (else_ + && TREE_CODE (else_) == GOTO_EXPR + && TREE_CODE (GOTO_DESTINATION (else_)) == LABEL_DECL) + { + false_label = GOTO_DESTINATION (else_); + else_ = NULL; + else_se = false; + } + + /* If we aren't hijacking a label for the 'then' branch, it falls through. */ + if (true_label) + true_label_p = &true_label; + else + true_label_p = NULL; + + /* The 'else' branch also needs a label if it contains interesting code. */ + if (false_label || else_se) + false_label_p = &false_label; + else + false_label_p = NULL; + + /* If there was nothing else in our arms, just forward the label(s). */ + if (!then_se && !else_se) + return shortcut_cond_r (pred, true_label_p, false_label_p); + + /* If our last subexpression already has a terminal label, reuse it. */ + if (else_se) + expr = expr_last (else_); + else if (then_se) + expr = expr_last (then_); + else + expr = NULL; + if (expr && TREE_CODE (expr) == LABEL_EXPR) + end_label = LABEL_EXPR_LABEL (expr); + + /* If we don't care about jumping to the 'else' branch, jump to the end + if the condition is false. */ + if (!false_label_p) + false_label_p = &end_label; + + /* We only want to emit these labels if we aren't hijacking them. */ + emit_end = (end_label == NULL_TREE); + emit_false = (false_label == NULL_TREE); + + /* We only emit the jump over the else clause if we have to--if the + then clause may fall through. Otherwise we can wind up with a + useless jump and a useless label at the end of gimplified code, + which will cause us to think that this conditional as a whole + falls through even if it doesn't. If we then inline a function + which ends with such a condition, that can cause us to issue an + inappropriate warning about control reaching the end of a + non-void function. */ + jump_over_else = block_may_fallthru (then_); + + pred = shortcut_cond_r (pred, true_label_p, false_label_p); + + expr = NULL; + append_to_statement_list (pred, &expr); + + append_to_statement_list (then_, &expr); + if (else_se) + { + if (jump_over_else) + { + t = build_and_jump (&end_label); + append_to_statement_list (t, &expr); + } + if (emit_false) + { + t = build1 (LABEL_EXPR, void_type_node, false_label); + append_to_statement_list (t, &expr); + } + append_to_statement_list (else_, &expr); + } + if (emit_end && end_label) + { + t = build1 (LABEL_EXPR, void_type_node, end_label); + append_to_statement_list (t, &expr); + } + + return expr; +} + +/* EXPR is used in a boolean context; make sure it has BOOLEAN_TYPE. */ + +tree +gimple_boolify (tree expr) +{ + tree type = TREE_TYPE (expr); + + if (TREE_CODE (type) == BOOLEAN_TYPE) + return expr; + + switch (TREE_CODE (expr)) + { + case TRUTH_AND_EXPR: + case TRUTH_OR_EXPR: + case TRUTH_XOR_EXPR: + case TRUTH_ANDIF_EXPR: + case TRUTH_ORIF_EXPR: + /* Also boolify the arguments of truth exprs. */ + TREE_OPERAND (expr, 1) = gimple_boolify (TREE_OPERAND (expr, 1)); + /* FALLTHRU */ + + case TRUTH_NOT_EXPR: + TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0)); + /* FALLTHRU */ + + case EQ_EXPR: case NE_EXPR: + case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR: + /* These expressions always produce boolean results. */ + TREE_TYPE (expr) = boolean_type_node; + return expr; + + default: + /* Other expressions that get here must have boolean values, but + might need to be converted to the appropriate mode. */ + return fold_convert (boolean_type_node, expr); + } +} + +/* Convert the conditional expression pointed to by EXPR_P '(p) ? a : b;' + into + + if (p) if (p) + t1 = a; a; + else or else + t1 = b; b; + t1; + + The second form is used when *EXPR_P is of type void. + + TARGET is the tree for T1 above. + + PRE_P points to the list where side effects that must happen before + *EXPR_P should be stored. */ + +static enum gimplify_status +gimplify_cond_expr (tree *expr_p, tree *pre_p, fallback_t fallback) +{ + tree expr = *expr_p; + tree tmp, tmp2, type; + enum gimplify_status ret; + + type = TREE_TYPE (expr); + + /* If this COND_EXPR has a value, copy the values into a temporary within + the arms. */ + if (! VOID_TYPE_P (type)) + { + tree result; + + if ((fallback & fb_lvalue) == 0) + { + result = tmp2 = tmp = create_tmp_var (TREE_TYPE (expr), "iftmp"); + ret = GS_ALL_DONE; + } + else + { + tree type = build_pointer_type (TREE_TYPE (expr)); + + if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node) + TREE_OPERAND (expr, 1) = + build_fold_addr_expr (TREE_OPERAND (expr, 1)); + + if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node) + TREE_OPERAND (expr, 2) = + build_fold_addr_expr (TREE_OPERAND (expr, 2)); + + tmp2 = tmp = create_tmp_var (type, "iftmp"); + + expr = build3 (COND_EXPR, void_type_node, TREE_OPERAND (expr, 0), + TREE_OPERAND (expr, 1), TREE_OPERAND (expr, 2)); + + result = build_fold_indirect_ref (tmp); + ret = GS_ALL_DONE; + } + + /* Build the then clause, 't1 = a;'. But don't build an assignment + if this branch is void; in C++ it can be, if it's a throw. */ + if (TREE_TYPE (TREE_OPERAND (expr, 1)) != void_type_node) + TREE_OPERAND (expr, 1) + = build2 (MODIFY_EXPR, void_type_node, tmp, TREE_OPERAND (expr, 1)); + + /* Build the else clause, 't1 = b;'. */ + if (TREE_TYPE (TREE_OPERAND (expr, 2)) != void_type_node) + TREE_OPERAND (expr, 2) + = build2 (MODIFY_EXPR, void_type_node, tmp2, TREE_OPERAND (expr, 2)); + + TREE_TYPE (expr) = void_type_node; + recalculate_side_effects (expr); + + /* Move the COND_EXPR to the prequeue. */ + gimplify_and_add (expr, pre_p); + + *expr_p = result; + return ret; + } + + /* Make sure the condition has BOOLEAN_TYPE. */ + TREE_OPERAND (expr, 0) = gimple_boolify (TREE_OPERAND (expr, 0)); + + /* Break apart && and || conditions. */ + if (TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ANDIF_EXPR + || TREE_CODE (TREE_OPERAND (expr, 0)) == TRUTH_ORIF_EXPR) + { + expr = shortcut_cond_expr (expr); + + if (expr != *expr_p) + { + *expr_p = expr; + + /* We can't rely on gimplify_expr to re-gimplify the expanded + form properly, as cleanups might cause the target labels to be + wrapped in a TRY_FINALLY_EXPR. To prevent that, we need to + set up a conditional context. */ + gimple_push_condition (); + gimplify_stmt (expr_p); + gimple_pop_condition (pre_p); + + return GS_ALL_DONE; + } + } + + /* Now do the normal gimplification. */ + ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL, + is_gimple_condexpr, fb_rvalue); + + gimple_push_condition (); + + gimplify_to_stmt_list (&TREE_OPERAND (expr, 1)); + gimplify_to_stmt_list (&TREE_OPERAND (expr, 2)); + recalculate_side_effects (expr); + + gimple_pop_condition (pre_p); + + if (ret == GS_ERROR) + ; + else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1))) + ret = GS_ALL_DONE; + else if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 2))) + /* Rewrite "if (a); else b" to "if (!a) b" */ + { + TREE_OPERAND (expr, 0) = invert_truthvalue (TREE_OPERAND (expr, 0)); + ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, NULL, + is_gimple_condexpr, fb_rvalue); + + tmp = TREE_OPERAND (expr, 1); + TREE_OPERAND (expr, 1) = TREE_OPERAND (expr, 2); + TREE_OPERAND (expr, 2) = tmp; + } + else + /* Both arms are empty; replace the COND_EXPR with its predicate. */ + expr = TREE_OPERAND (expr, 0); + + *expr_p = expr; + return ret; +} + +/* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with + a call to __builtin_memcpy. */ + +static enum gimplify_status +gimplify_modify_expr_to_memcpy (tree *expr_p, tree size, bool want_value) +{ + tree args, t, to, to_ptr, from; + + to = TREE_OPERAND (*expr_p, 0); + from = TREE_OPERAND (*expr_p, 1); + + args = tree_cons (NULL, size, NULL); + + t = build_fold_addr_expr (from); + args = tree_cons (NULL, t, args); + + to_ptr = build_fold_addr_expr (to); + args = tree_cons (NULL, to_ptr, args); + t = implicit_built_in_decls[BUILT_IN_MEMCPY]; + t = build_function_call_expr (t, args); + + if (want_value) + { + t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t); + t = build1 (INDIRECT_REF, TREE_TYPE (to), t); + } + + *expr_p = t; + return GS_OK; +} + +/* A subroutine of gimplify_modify_expr. Replace a MODIFY_EXPR with + a call to __builtin_memset. In this case we know that the RHS is + a CONSTRUCTOR with an empty element list. */ + +static enum gimplify_status +gimplify_modify_expr_to_memset (tree *expr_p, tree size, bool want_value) +{ + tree args, t, to, to_ptr; + + to = TREE_OPERAND (*expr_p, 0); + + args = tree_cons (NULL, size, NULL); + + args = tree_cons (NULL, integer_zero_node, args); + + to_ptr = build_fold_addr_expr (to); + args = tree_cons (NULL, to_ptr, args); + t = implicit_built_in_decls[BUILT_IN_MEMSET]; + t = build_function_call_expr (t, args); + + if (want_value) + { + t = build1 (NOP_EXPR, TREE_TYPE (to_ptr), t); + t = build1 (INDIRECT_REF, TREE_TYPE (to), t); + } + + *expr_p = t; + return GS_OK; +} + +/* A subroutine of gimplify_init_ctor_preeval. Called via walk_tree, + determine, cautiously, if a CONSTRUCTOR overlaps the lhs of an + assignment. Returns non-null if we detect a potential overlap. */ + +struct gimplify_init_ctor_preeval_data +{ + /* The base decl of the lhs object. May be NULL, in which case we + have to assume the lhs is indirect. */ + tree lhs_base_decl; + + /* The alias set of the lhs object. */ + int lhs_alias_set; +}; + +static tree +gimplify_init_ctor_preeval_1 (tree *tp, int *walk_subtrees, void *xdata) +{ + struct gimplify_init_ctor_preeval_data *data + = (struct gimplify_init_ctor_preeval_data *) xdata; + tree t = *tp; + + /* If we find the base object, obviously we have overlap. */ + if (data->lhs_base_decl == t) + return t; + + /* If the constructor component is indirect, determine if we have a + potential overlap with the lhs. The only bits of information we + have to go on at this point are addressability and alias sets. */ + if (TREE_CODE (t) == INDIRECT_REF + && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl)) + && alias_sets_conflict_p (data->lhs_alias_set, get_alias_set (t))) + return t; + + /* If the constructor component is a call, determine if it can hide a + potential overlap with the lhs through an INDIRECT_REF like above. */ + if (TREE_CODE (t) == CALL_EXPR) + { + tree type, fntype = TREE_TYPE (TREE_TYPE (TREE_OPERAND (t, 0))); + + for (type = TYPE_ARG_TYPES (fntype); type; type = TREE_CHAIN (type)) + if (POINTER_TYPE_P (TREE_VALUE (type)) + && (!data->lhs_base_decl || TREE_ADDRESSABLE (data->lhs_base_decl)) + && alias_sets_conflict_p (data->lhs_alias_set, + get_alias_set + (TREE_TYPE (TREE_VALUE (type))))) + return t; + } + + if (IS_TYPE_OR_DECL_P (t)) + *walk_subtrees = 0; + return NULL; +} + +/* A subroutine of gimplify_init_constructor. Pre-evaluate *EXPR_P, + force values that overlap with the lhs (as described by *DATA) + into temporaries. */ + +static void +gimplify_init_ctor_preeval (tree *expr_p, tree *pre_p, tree *post_p, + struct gimplify_init_ctor_preeval_data *data) +{ + enum gimplify_status one; + + /* If the value is invariant, then there's nothing to pre-evaluate. + But ensure it doesn't have any side-effects since a SAVE_EXPR is + invariant but has side effects and might contain a reference to + the object we're initializing. */ + if (TREE_INVARIANT (*expr_p) && !TREE_SIDE_EFFECTS (*expr_p)) + return; + + /* If the type has non-trivial constructors, we can't pre-evaluate. */ + if (TREE_ADDRESSABLE (TREE_TYPE (*expr_p))) + return; + + /* Recurse for nested constructors. */ + if (TREE_CODE (*expr_p) == CONSTRUCTOR) + { + unsigned HOST_WIDE_INT ix; + constructor_elt *ce; + VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (*expr_p); + + for (ix = 0; VEC_iterate (constructor_elt, v, ix, ce); ix++) + gimplify_init_ctor_preeval (&ce->value, pre_p, post_p, data); + return; + } + + /* If this is a variable sized type, we must remember the size. */ + maybe_with_size_expr (expr_p); + + /* Gimplify the constructor element to something appropriate for the rhs + of a MODIFY_EXPR. Given that we know the lhs is an aggregate, we know + the gimplifier will consider this a store to memory. Doing this + gimplification now means that we won't have to deal with complicated + language-specific trees, nor trees like SAVE_EXPR that can induce + exponential search behavior. */ + one = gimplify_expr (expr_p, pre_p, post_p, is_gimple_mem_rhs, fb_rvalue); + if (one == GS_ERROR) + { + *expr_p = NULL; + return; + } + + /* If we gimplified to a bare decl, we can be sure that it doesn't overlap + with the lhs, since "a = { .x=a }" doesn't make sense. This will + always be true for all scalars, since is_gimple_mem_rhs insists on a + temporary variable for them. */ + if (DECL_P (*expr_p)) + return; + + /* If this is of variable size, we have no choice but to assume it doesn't + overlap since we can't make a temporary for it. */ + if (TREE_CODE (TYPE_SIZE (TREE_TYPE (*expr_p))) != INTEGER_CST) + return; + + /* Otherwise, we must search for overlap ... */ + if (!walk_tree (expr_p, gimplify_init_ctor_preeval_1, data, NULL)) + return; + + /* ... and if found, force the value into a temporary. */ + *expr_p = get_formal_tmp_var (*expr_p, pre_p); +} + +/* A subroutine of gimplify_init_ctor_eval. Create a loop for + a RANGE_EXPR in a CONSTRUCTOR for an array. + + var = lower; + loop_entry: + object[var] = value; + if (var == upper) + goto loop_exit; + var = var + 1; + goto loop_entry; + loop_exit: + + We increment var _after_ the loop exit check because we might otherwise + fail if upper == TYPE_MAX_VALUE (type for upper). + + Note that we never have to deal with SAVE_EXPRs here, because this has + already been taken care of for us, in gimplify_init_ctor_preeval(). */ + +static void gimplify_init_ctor_eval (tree, VEC(constructor_elt,gc) *, + tree *, bool); + +static void +gimplify_init_ctor_eval_range (tree object, tree lower, tree upper, + tree value, tree array_elt_type, + tree *pre_p, bool cleared) +{ + tree loop_entry_label, loop_exit_label; + tree var, var_type, cref; + + loop_entry_label = create_artificial_label (); + loop_exit_label = create_artificial_label (); + + /* Create and initialize the index variable. */ + var_type = TREE_TYPE (upper); + var = create_tmp_var (var_type, NULL); + append_to_statement_list (build2 (MODIFY_EXPR, var_type, var, lower), pre_p); + + /* Add the loop entry label. */ + append_to_statement_list (build1 (LABEL_EXPR, + void_type_node, + loop_entry_label), + pre_p); + + /* Build the reference. */ + cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object), + var, NULL_TREE, NULL_TREE); + + /* If we are a constructor, just call gimplify_init_ctor_eval to do + the store. Otherwise just assign value to the reference. */ + + if (TREE_CODE (value) == CONSTRUCTOR) + /* NB we might have to call ourself recursively through + gimplify_init_ctor_eval if the value is a constructor. */ + gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value), + pre_p, cleared); + else + append_to_statement_list (build2 (MODIFY_EXPR, TREE_TYPE (cref), + cref, value), + pre_p); + + /* We exit the loop when the index var is equal to the upper bound. */ + gimplify_and_add (build3 (COND_EXPR, void_type_node, + build2 (EQ_EXPR, boolean_type_node, + var, upper), + build1 (GOTO_EXPR, + void_type_node, + loop_exit_label), + NULL_TREE), + pre_p); + + /* Otherwise, increment the index var... */ + append_to_statement_list (build2 (MODIFY_EXPR, var_type, var, + build2 (PLUS_EXPR, var_type, var, + fold_convert (var_type, + integer_one_node))), + pre_p); + + /* ...and jump back to the loop entry. */ + append_to_statement_list (build1 (GOTO_EXPR, + void_type_node, + loop_entry_label), + pre_p); + + /* Add the loop exit label. */ + append_to_statement_list (build1 (LABEL_EXPR, + void_type_node, + loop_exit_label), + pre_p); +} + +/* Return true if FDECL is accessing a field that is zero sized. */ + +static bool +zero_sized_field_decl (tree fdecl) +{ + if (TREE_CODE (fdecl) == FIELD_DECL && DECL_SIZE (fdecl) + && integer_zerop (DECL_SIZE (fdecl))) + return true; + return false; +} + +/* Return true if TYPE is zero sized. */ + +static bool +zero_sized_type (tree type) +{ + if (AGGREGATE_TYPE_P (type) && TYPE_SIZE (type) + && integer_zerop (TYPE_SIZE (type))) + return true; + return false; +} + +/* A subroutine of gimplify_init_constructor. Generate individual + MODIFY_EXPRs for a CONSTRUCTOR. OBJECT is the LHS against which the + assignments should happen. ELTS is the CONSTRUCTOR_ELTS of the + CONSTRUCTOR. CLEARED is true if the entire LHS object has been + zeroed first. */ + +static void +gimplify_init_ctor_eval (tree object, VEC(constructor_elt,gc) *elts, + tree *pre_p, bool cleared) +{ + tree array_elt_type = NULL; + unsigned HOST_WIDE_INT ix; + tree purpose, value; + + if (TREE_CODE (TREE_TYPE (object)) == ARRAY_TYPE) + array_elt_type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (object))); + + FOR_EACH_CONSTRUCTOR_ELT (elts, ix, purpose, value) + { + tree cref, init; + + /* NULL values are created above for gimplification errors. */ + if (value == NULL) + continue; + + if (cleared && initializer_zerop (value)) + continue; + + /* ??? Here's to hoping the front end fills in all of the indices, + so we don't have to figure out what's missing ourselves. */ + gcc_assert (purpose); + + /* Skip zero-sized fields, unless value has side-effects. This can + happen with calls to functions returning a zero-sized type, which + we shouldn't discard. As a number of downstream passes don't + expect sets of zero-sized fields, we rely on the gimplification of + the MODIFY_EXPR we make below to drop the assignment statement. */ + if (! TREE_SIDE_EFFECTS (value) && zero_sized_field_decl (purpose)) + continue; + + /* If we have a RANGE_EXPR, we have to build a loop to assign the + whole range. */ + if (TREE_CODE (purpose) == RANGE_EXPR) + { + tree lower = TREE_OPERAND (purpose, 0); + tree upper = TREE_OPERAND (purpose, 1); + + /* If the lower bound is equal to upper, just treat it as if + upper was the index. */ + if (simple_cst_equal (lower, upper)) + purpose = upper; + else + { + gimplify_init_ctor_eval_range (object, lower, upper, value, + array_elt_type, pre_p, cleared); + continue; + } + } + + if (array_elt_type) + { + cref = build4 (ARRAY_REF, array_elt_type, unshare_expr (object), + purpose, NULL_TREE, NULL_TREE); + } + else + { + gcc_assert (TREE_CODE (purpose) == FIELD_DECL); + cref = build3 (COMPONENT_REF, TREE_TYPE (purpose), + unshare_expr (object), purpose, NULL_TREE); + } + + if (TREE_CODE (value) == CONSTRUCTOR + && TREE_CODE (TREE_TYPE (value)) != VECTOR_TYPE) + gimplify_init_ctor_eval (cref, CONSTRUCTOR_ELTS (value), + pre_p, cleared); + else + { + init = build2 (INIT_EXPR, TREE_TYPE (cref), cref, value); + gimplify_and_add (init, pre_p); + } + } +} + +/* A subroutine of gimplify_modify_expr. Break out elements of a + CONSTRUCTOR used as an initializer into separate MODIFY_EXPRs. + + Note that we still need to clear any elements that don't have explicit + initializers, so if not all elements are initialized we keep the + original MODIFY_EXPR, we just remove all of the constructor elements. */ + +static enum gimplify_status +gimplify_init_constructor (tree *expr_p, tree *pre_p, + tree *post_p, bool want_value) +{ + tree object; + tree ctor = TREE_OPERAND (*expr_p, 1); + tree type = TREE_TYPE (ctor); + enum gimplify_status ret; + VEC(constructor_elt,gc) *elts; + + if (TREE_CODE (ctor) != CONSTRUCTOR) + return GS_UNHANDLED; + + ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p, + is_gimple_lvalue, fb_lvalue); + if (ret == GS_ERROR) + return ret; + object = TREE_OPERAND (*expr_p, 0); + + elts = CONSTRUCTOR_ELTS (ctor); + + ret = GS_ALL_DONE; + switch (TREE_CODE (type)) + { + case RECORD_TYPE: + case UNION_TYPE: + case QUAL_UNION_TYPE: + case ARRAY_TYPE: + { + struct gimplify_init_ctor_preeval_data preeval_data; + HOST_WIDE_INT num_type_elements, num_ctor_elements; + HOST_WIDE_INT num_nonzero_elements; + bool cleared, valid_const_initializer; + + /* Aggregate types must lower constructors to initialization of + individual elements. The exception is that a CONSTRUCTOR node + with no elements indicates zero-initialization of the whole. */ + if (VEC_empty (constructor_elt, elts)) + break; + + /* Fetch information about the constructor to direct later processing. + We might want to make static versions of it in various cases, and + can only do so if it known to be a valid constant initializer. */ + valid_const_initializer + = categorize_ctor_elements (ctor, &num_nonzero_elements, + &num_ctor_elements, &cleared); + + /* If a const aggregate variable is being initialized, then it + should never be a lose to promote the variable to be static. */ + if (valid_const_initializer + && num_nonzero_elements > 1 + && TREE_READONLY (object) + && TREE_CODE (object) == VAR_DECL) + { + DECL_INITIAL (object) = ctor; + TREE_STATIC (object) = 1; + if (!DECL_NAME (object)) + DECL_NAME (object) = create_tmp_var_name ("C"); + walk_tree (&DECL_INITIAL (object), force_labels_r, NULL, NULL); + + /* ??? C++ doesn't automatically append a .<number> to the + assembler name, and even when it does, it looks a FE private + data structures to figure out what that number should be, + which are not set for this variable. I suppose this is + important for local statics for inline functions, which aren't + "local" in the object file sense. So in order to get a unique + TU-local symbol, we must invoke the lhd version now. */ + lhd_set_decl_assembler_name (object); + + *expr_p = NULL_TREE; + break; + } + + /* If there are "lots" of initialized elements, even discounting + those that are not address constants (and thus *must* be + computed at runtime), then partition the constructor into + constant and non-constant parts. Block copy the constant + parts in, then generate code for the non-constant parts. */ + /* TODO. There's code in cp/typeck.c to do this. */ + + num_type_elements = count_type_elements (type, true); + + /* If count_type_elements could not determine number of type elements + for a constant-sized object, assume clearing is needed. + Don't do this for variable-sized objects, as store_constructor + will ignore the clearing of variable-sized objects. */ + if (num_type_elements < 0 && int_size_in_bytes (type) >= 0) + cleared = true; + /* If there are "lots" of zeros, then block clear the object first. */ + else if (num_type_elements - num_nonzero_elements > CLEAR_RATIO + && num_nonzero_elements < num_type_elements/4) + cleared = true; + /* ??? This bit ought not be needed. For any element not present + in the initializer, we should simply set them to zero. Except + we'd need to *find* the elements that are not present, and that + requires trickery to avoid quadratic compile-time behavior in + large cases or excessive memory use in small cases. */ + else if (num_ctor_elements < num_type_elements) + cleared = true; + + /* If there are "lots" of initialized elements, and all of them + are valid address constants, then the entire initializer can + be dropped to memory, and then memcpy'd out. Don't do this + for sparse arrays, though, as it's more efficient to follow + the standard CONSTRUCTOR behavior of memset followed by + individual element initialization. */ + if (valid_const_initializer && !cleared) + { + HOST_WIDE_INT size = int_size_in_bytes (type); + unsigned int align; + + /* ??? We can still get unbounded array types, at least + from the C++ front end. This seems wrong, but attempt + to work around it for now. */ + if (size < 0) + { + size = int_size_in_bytes (TREE_TYPE (object)); + if (size >= 0) + TREE_TYPE (ctor) = type = TREE_TYPE (object); + } + + /* Find the maximum alignment we can assume for the object. */ + /* ??? Make use of DECL_OFFSET_ALIGN. */ + if (DECL_P (object)) + align = DECL_ALIGN (object); + else + align = TYPE_ALIGN (type); + + if (size > 0 && !can_move_by_pieces (size, align)) + { + tree new = create_tmp_var_raw (type, "C"); + + gimple_add_tmp_var (new); + TREE_STATIC (new) = 1; + TREE_READONLY (new) = 1; + DECL_INITIAL (new) = ctor; + if (align > DECL_ALIGN (new)) + { + DECL_ALIGN (new) = align; + DECL_USER_ALIGN (new) = 1; + } + walk_tree (&DECL_INITIAL (new), force_labels_r, NULL, NULL); + + TREE_OPERAND (*expr_p, 1) = new; + + /* This is no longer an assignment of a CONSTRUCTOR, but + we still may have processing to do on the LHS. So + pretend we didn't do anything here to let that happen. */ + return GS_UNHANDLED; + } + } + + /* If there are nonzero elements, pre-evaluate to capture elements + overlapping with the lhs into temporaries. We must do this before + clearing to fetch the values before they are zeroed-out. */ + if (num_nonzero_elements > 0) + { + preeval_data.lhs_base_decl = get_base_address (object); + if (!DECL_P (preeval_data.lhs_base_decl)) + preeval_data.lhs_base_decl = NULL; + preeval_data.lhs_alias_set = get_alias_set (object); + + gimplify_init_ctor_preeval (&TREE_OPERAND (*expr_p, 1), + pre_p, post_p, &preeval_data); + } + + if (cleared) + { + /* Zap the CONSTRUCTOR element list, which simplifies this case. + Note that we still have to gimplify, in order to handle the + case of variable sized types. Avoid shared tree structures. */ + CONSTRUCTOR_ELTS (ctor) = NULL; + object = unshare_expr (object); + gimplify_stmt (expr_p); + append_to_statement_list (*expr_p, pre_p); + } + + /* If we have not block cleared the object, or if there are nonzero + elements in the constructor, add assignments to the individual + scalar fields of the object. */ + if (!cleared || num_nonzero_elements > 0) + gimplify_init_ctor_eval (object, elts, pre_p, cleared); + + *expr_p = NULL_TREE; + } + break; + + case COMPLEX_TYPE: + { + tree r, i; + + /* Extract the real and imaginary parts out of the ctor. */ + gcc_assert (VEC_length (constructor_elt, elts) == 2); + r = VEC_index (constructor_elt, elts, 0)->value; + i = VEC_index (constructor_elt, elts, 1)->value; + if (r == NULL || i == NULL) + { + tree zero = fold_convert (TREE_TYPE (type), integer_zero_node); + if (r == NULL) + r = zero; + if (i == NULL) + i = zero; + } + + /* Complex types have either COMPLEX_CST or COMPLEX_EXPR to + represent creation of a complex value. */ + if (TREE_CONSTANT (r) && TREE_CONSTANT (i)) + { + ctor = build_complex (type, r, i); + TREE_OPERAND (*expr_p, 1) = ctor; + } + else + { + ctor = build2 (COMPLEX_EXPR, type, r, i); + TREE_OPERAND (*expr_p, 1) = ctor; + ret = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p, + rhs_predicate_for (TREE_OPERAND (*expr_p, 0)), + fb_rvalue); + } + } + break; + + case VECTOR_TYPE: + { + unsigned HOST_WIDE_INT ix; + constructor_elt *ce; + + /* Go ahead and simplify constant constructors to VECTOR_CST. */ + if (TREE_CONSTANT (ctor)) + { + bool constant_p = true; + tree value; + + /* Even when ctor is constant, it might contain non-*_CST + elements (e.g. { 1.0/0.0 - 1.0/0.0, 0.0 }) and those don't + belong into VECTOR_CST nodes. */ + FOR_EACH_CONSTRUCTOR_VALUE (elts, ix, value) + if (!CONSTANT_CLASS_P (value)) + { + constant_p = false; + break; + } + + if (constant_p) + { + TREE_OPERAND (*expr_p, 1) = build_vector_from_ctor (type, elts); + break; + } + + /* Don't reduce a TREE_CONSTANT vector ctor even if we can't + make a VECTOR_CST. It won't do anything for us, and it'll + prevent us from representing it as a single constant. */ + break; + } + + /* Vector types use CONSTRUCTOR all the way through gimple + compilation as a general initializer. */ + for (ix = 0; VEC_iterate (constructor_elt, elts, ix, ce); ix++) + { + enum gimplify_status tret; + tret = gimplify_expr (&ce->value, pre_p, post_p, + is_gimple_val, fb_rvalue); + if (tret == GS_ERROR) + ret = GS_ERROR; + } + } + break; + + default: + /* So how did we get a CONSTRUCTOR for a scalar type? */ + gcc_unreachable (); + } + + if (ret == GS_ERROR) + return GS_ERROR; + else if (want_value) + { + append_to_statement_list (*expr_p, pre_p); + *expr_p = object; + return GS_OK; + } + else + return GS_ALL_DONE; +} + +/* Given a pointer value OP0, return a simplified version of an + indirection through OP0, or NULL_TREE if no simplification is + possible. This may only be applied to a rhs of an expression. + Note that the resulting type may be different from the type pointed + to in the sense that it is still compatible from the langhooks + point of view. */ + +static tree +fold_indirect_ref_rhs (tree t) +{ + tree type = TREE_TYPE (TREE_TYPE (t)); + tree sub = t; + tree subtype; + + STRIP_USELESS_TYPE_CONVERSION (sub); + subtype = TREE_TYPE (sub); + if (!POINTER_TYPE_P (subtype)) + return NULL_TREE; + + if (TREE_CODE (sub) == ADDR_EXPR) + { + tree op = TREE_OPERAND (sub, 0); + tree optype = TREE_TYPE (op); + /* *&p => p */ + if (lang_hooks.types_compatible_p (type, optype)) + return op; + /* *(foo *)&fooarray => fooarray[0] */ + else if (TREE_CODE (optype) == ARRAY_TYPE + && lang_hooks.types_compatible_p (type, TREE_TYPE (optype))) + { + tree type_domain = TYPE_DOMAIN (optype); + tree min_val = size_zero_node; + if (type_domain && TYPE_MIN_VALUE (type_domain)) + min_val = TYPE_MIN_VALUE (type_domain); + return build4 (ARRAY_REF, type, op, min_val, NULL_TREE, NULL_TREE); + } + } + + /* *(foo *)fooarrptr => (*fooarrptr)[0] */ + if (TREE_CODE (TREE_TYPE (subtype)) == ARRAY_TYPE + && lang_hooks.types_compatible_p (type, TREE_TYPE (TREE_TYPE (subtype)))) + { + tree type_domain; + tree min_val = size_zero_node; + tree osub = sub; + sub = fold_indirect_ref_rhs (sub); + if (! sub) + sub = build1 (INDIRECT_REF, TREE_TYPE (subtype), osub); + type_domain = TYPE_DOMAIN (TREE_TYPE (sub)); + if (type_domain && TYPE_MIN_VALUE (type_domain)) + min_val = TYPE_MIN_VALUE (type_domain); + return build4 (ARRAY_REF, type, sub, min_val, NULL_TREE, NULL_TREE); + } + + return NULL_TREE; +} + +/* Subroutine of gimplify_modify_expr to do simplifications of MODIFY_EXPRs + based on the code of the RHS. We loop for as long as something changes. */ + +static enum gimplify_status +gimplify_modify_expr_rhs (tree *expr_p, tree *from_p, tree *to_p, tree *pre_p, + tree *post_p, bool want_value) +{ + enum gimplify_status ret = GS_OK; + + while (ret != GS_UNHANDLED) + switch (TREE_CODE (*from_p)) + { + case INDIRECT_REF: + { + /* If we have code like + + *(const A*)(A*)&x + + where the type of "x" is a (possibly cv-qualified variant + of "A"), treat the entire expression as identical to "x". + This kind of code arises in C++ when an object is bound + to a const reference, and if "x" is a TARGET_EXPR we want + to take advantage of the optimization below. */ + tree t = fold_indirect_ref_rhs (TREE_OPERAND (*from_p, 0)); + if (t) + { + *from_p = t; + ret = GS_OK; + } + else + ret = GS_UNHANDLED; + break; + } + + case TARGET_EXPR: + { + /* If we are initializing something from a TARGET_EXPR, strip the + TARGET_EXPR and initialize it directly, if possible. This can't + be done if the initializer is void, since that implies that the + temporary is set in some non-trivial way. + + ??? What about code that pulls out the temp and uses it + elsewhere? I think that such code never uses the TARGET_EXPR as + an initializer. If I'm wrong, we'll die because the temp won't + have any RTL. In that case, I guess we'll need to replace + references somehow. */ + tree init = TARGET_EXPR_INITIAL (*from_p); + + if (!VOID_TYPE_P (TREE_TYPE (init))) + { + *from_p = init; + ret = GS_OK; + } + else + ret = GS_UNHANDLED; + } + break; + + case COMPOUND_EXPR: + /* Remove any COMPOUND_EXPR in the RHS so the following cases will be + caught. */ + gimplify_compound_expr (from_p, pre_p, true); + ret = GS_OK; + break; + + case CONSTRUCTOR: + /* If we're initializing from a CONSTRUCTOR, break this into + individual MODIFY_EXPRs. */ + return gimplify_init_constructor (expr_p, pre_p, post_p, want_value); + + case COND_EXPR: + /* If we're assigning to a non-register type, push the assignment + down into the branches. This is mandatory for ADDRESSABLE types, + since we cannot generate temporaries for such, but it saves a + copy in other cases as well. */ + if (!is_gimple_reg_type (TREE_TYPE (*from_p))) + { + /* This code should mirror the code in gimplify_cond_expr. */ + enum tree_code code = TREE_CODE (*expr_p); + tree cond = *from_p; + tree result = *to_p; + + ret = gimplify_expr (&result, pre_p, post_p, + is_gimple_min_lval, fb_lvalue); + if (ret != GS_ERROR) + ret = GS_OK; + + if (TREE_TYPE (TREE_OPERAND (cond, 1)) != void_type_node) + TREE_OPERAND (cond, 1) + = build2 (code, void_type_node, result, + TREE_OPERAND (cond, 1)); + if (TREE_TYPE (TREE_OPERAND (cond, 2)) != void_type_node) + TREE_OPERAND (cond, 2) + = build2 (code, void_type_node, unshare_expr (result), + TREE_OPERAND (cond, 2)); + + TREE_TYPE (cond) = void_type_node; + recalculate_side_effects (cond); + + if (want_value) + { + gimplify_and_add (cond, pre_p); + *expr_p = unshare_expr (result); + } + else + *expr_p = cond; + return ret; + } + else + ret = GS_UNHANDLED; + break; + + case CALL_EXPR: + /* For calls that return in memory, give *to_p as the CALL_EXPR's + return slot so that we don't generate a temporary. */ + if (!CALL_EXPR_RETURN_SLOT_OPT (*from_p) + && aggregate_value_p (*from_p, *from_p)) + { + bool use_target; + + if (!(rhs_predicate_for (*to_p))(*from_p)) + /* If we need a temporary, *to_p isn't accurate. */ + use_target = false; + else if (TREE_CODE (*to_p) == RESULT_DECL + && DECL_NAME (*to_p) == NULL_TREE + && needs_to_live_in_memory (*to_p)) + /* It's OK to use the return slot directly unless it's an NRV. */ + use_target = true; + else if (is_gimple_reg_type (TREE_TYPE (*to_p)) + || (DECL_P (*to_p) && DECL_REGISTER (*to_p))) + /* Don't force regs into memory. */ + use_target = false; + else if (TREE_CODE (*to_p) == VAR_DECL + && DECL_GIMPLE_FORMAL_TEMP_P (*to_p)) + /* Don't use the original target if it's a formal temp; we + don't want to take their addresses. */ + use_target = false; + else if (TREE_CODE (*expr_p) == INIT_EXPR) + /* It's OK to use the target directly if it's being + initialized. */ + use_target = true; + else if (!is_gimple_non_addressable (*to_p)) + /* Don't use the original target if it's already addressable; + if its address escapes, and the called function uses the + NRV optimization, a conforming program could see *to_p + change before the called function returns; see c++/19317. + When optimizing, the return_slot pass marks more functions + as safe after we have escape info. */ + use_target = false; + else + use_target = true; + + if (use_target) + { + CALL_EXPR_RETURN_SLOT_OPT (*from_p) = 1; + lang_hooks.mark_addressable (*to_p); + } + } + + ret = GS_UNHANDLED; + break; + + /* If we're initializing from a container, push the initialization + inside it. */ + case CLEANUP_POINT_EXPR: + case BIND_EXPR: + case STATEMENT_LIST: + { + tree wrap = *from_p; + tree t; + + ret = gimplify_expr (to_p, pre_p, post_p, + is_gimple_min_lval, fb_lvalue); + if (ret != GS_ERROR) + ret = GS_OK; + + t = voidify_wrapper_expr (wrap, *expr_p); + gcc_assert (t == *expr_p); + + if (want_value) + { + gimplify_and_add (wrap, pre_p); + *expr_p = unshare_expr (*to_p); + } + else + *expr_p = wrap; + return GS_OK; + } + + default: + ret = GS_UNHANDLED; + break; + } + + return ret; +} + +/* Promote partial stores to COMPLEX variables to total stores. *EXPR_P is + a MODIFY_EXPR with a lhs of a REAL/IMAGPART_EXPR of a variable with + DECL_COMPLEX_GIMPLE_REG_P set. */ + +static enum gimplify_status +gimplify_modify_expr_complex_part (tree *expr_p, tree *pre_p, bool want_value) +{ + enum tree_code code, ocode; + tree lhs, rhs, new_rhs, other, realpart, imagpart; + + lhs = TREE_OPERAND (*expr_p, 0); + rhs = TREE_OPERAND (*expr_p, 1); + code = TREE_CODE (lhs); + lhs = TREE_OPERAND (lhs, 0); + + ocode = code == REALPART_EXPR ? IMAGPART_EXPR : REALPART_EXPR; + other = build1 (ocode, TREE_TYPE (rhs), lhs); + other = get_formal_tmp_var (other, pre_p); + + realpart = code == REALPART_EXPR ? rhs : other; + imagpart = code == REALPART_EXPR ? other : rhs; + + if (TREE_CONSTANT (realpart) && TREE_CONSTANT (imagpart)) + new_rhs = build_complex (TREE_TYPE (lhs), realpart, imagpart); + else + new_rhs = build2 (COMPLEX_EXPR, TREE_TYPE (lhs), realpart, imagpart); + + TREE_OPERAND (*expr_p, 0) = lhs; + TREE_OPERAND (*expr_p, 1) = new_rhs; + + if (want_value) + { + append_to_statement_list (*expr_p, pre_p); + *expr_p = rhs; + } + + return GS_ALL_DONE; +} + +/* Gimplify the MODIFY_EXPR node pointed to by EXPR_P. + + modify_expr + : varname '=' rhs + | '*' ID '=' rhs + + PRE_P points to the list where side effects that must happen before + *EXPR_P should be stored. + + POST_P points to the list where side effects that must happen after + *EXPR_P should be stored. + + WANT_VALUE is nonzero iff we want to use the value of this expression + in another expression. */ + +static enum gimplify_status +gimplify_modify_expr (tree *expr_p, tree *pre_p, tree *post_p, bool want_value) +{ + tree *from_p = &TREE_OPERAND (*expr_p, 1); + tree *to_p = &TREE_OPERAND (*expr_p, 0); + enum gimplify_status ret = GS_UNHANDLED; + + gcc_assert (TREE_CODE (*expr_p) == MODIFY_EXPR + || TREE_CODE (*expr_p) == INIT_EXPR); + + /* For zero sized types only gimplify the left hand side and right hand side + as statements and throw away the assignment. */ + if (zero_sized_type (TREE_TYPE (*from_p))) + { + gimplify_stmt (from_p); + gimplify_stmt (to_p); + append_to_statement_list (*from_p, pre_p); + append_to_statement_list (*to_p, pre_p); + *expr_p = NULL_TREE; + return GS_ALL_DONE; + } + + /* See if any simplifications can be done based on what the RHS is. */ + ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p, + want_value); + if (ret != GS_UNHANDLED) + return ret; + + /* If the value being copied is of variable width, compute the length + of the copy into a WITH_SIZE_EXPR. Note that we need to do this + before gimplifying any of the operands so that we can resolve any + PLACEHOLDER_EXPRs in the size. Also note that the RTL expander uses + the size of the expression to be copied, not of the destination, so + that is what we must here. */ + maybe_with_size_expr (from_p); + + ret = gimplify_expr (to_p, pre_p, post_p, is_gimple_lvalue, fb_lvalue); + if (ret == GS_ERROR) + return ret; + + ret = gimplify_expr (from_p, pre_p, post_p, + rhs_predicate_for (*to_p), fb_rvalue); + if (ret == GS_ERROR) + return ret; + + /* Now see if the above changed *from_p to something we handle specially. */ + ret = gimplify_modify_expr_rhs (expr_p, from_p, to_p, pre_p, post_p, + want_value); + if (ret != GS_UNHANDLED) + return ret; + + /* If we've got a variable sized assignment between two lvalues (i.e. does + not involve a call), then we can make things a bit more straightforward + by converting the assignment to memcpy or memset. */ + if (TREE_CODE (*from_p) == WITH_SIZE_EXPR) + { + tree from = TREE_OPERAND (*from_p, 0); + tree size = TREE_OPERAND (*from_p, 1); + + if (TREE_CODE (from) == CONSTRUCTOR) + return gimplify_modify_expr_to_memset (expr_p, size, want_value); + if (is_gimple_addressable (from)) + { + *from_p = from; + return gimplify_modify_expr_to_memcpy (expr_p, size, want_value); + } + } + + /* Transform partial stores to non-addressable complex variables into + total stores. This allows us to use real instead of virtual operands + for these variables, which improves optimization. */ + if ((TREE_CODE (*to_p) == REALPART_EXPR + || TREE_CODE (*to_p) == IMAGPART_EXPR) + && is_gimple_reg (TREE_OPERAND (*to_p, 0))) + return gimplify_modify_expr_complex_part (expr_p, pre_p, want_value); + + if (gimplify_ctxp->into_ssa && is_gimple_reg (*to_p)) + { + /* If we've somehow already got an SSA_NAME on the LHS, then + we're probably modified it twice. Not good. */ + gcc_assert (TREE_CODE (*to_p) != SSA_NAME); + *to_p = make_ssa_name (*to_p, *expr_p); + } + + if (want_value) + { + append_to_statement_list (*expr_p, pre_p); + *expr_p = *to_p; + return GS_OK; + } + + return GS_ALL_DONE; +} + +/* Gimplify a comparison between two variable-sized objects. Do this + with a call to BUILT_IN_MEMCMP. */ + +static enum gimplify_status +gimplify_variable_sized_compare (tree *expr_p) +{ + tree op0 = TREE_OPERAND (*expr_p, 0); + tree op1 = TREE_OPERAND (*expr_p, 1); + tree args, t, dest; + + t = TYPE_SIZE_UNIT (TREE_TYPE (op0)); + t = unshare_expr (t); + t = SUBSTITUTE_PLACEHOLDER_IN_EXPR (t, op0); + args = tree_cons (NULL, t, NULL); + t = build_fold_addr_expr (op1); + args = tree_cons (NULL, t, args); + dest = build_fold_addr_expr (op0); + args = tree_cons (NULL, dest, args); + t = implicit_built_in_decls[BUILT_IN_MEMCMP]; + t = build_function_call_expr (t, args); + *expr_p + = build2 (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), t, integer_zero_node); + + return GS_OK; +} + +/* Gimplify a comparison between two aggregate objects of integral scalar + mode as a comparison between the bitwise equivalent scalar values. */ + +static enum gimplify_status +gimplify_scalar_mode_aggregate_compare (tree *expr_p) +{ + tree op0 = TREE_OPERAND (*expr_p, 0); + tree op1 = TREE_OPERAND (*expr_p, 1); + + tree type = TREE_TYPE (op0); + tree scalar_type = lang_hooks.types.type_for_mode (TYPE_MODE (type), 1); + + op0 = fold_build1 (VIEW_CONVERT_EXPR, scalar_type, op0); + op1 = fold_build1 (VIEW_CONVERT_EXPR, scalar_type, op1); + + *expr_p + = fold_build2 (TREE_CODE (*expr_p), TREE_TYPE (*expr_p), op0, op1); + + return GS_OK; +} + +/* Gimplify TRUTH_ANDIF_EXPR and TRUTH_ORIF_EXPR expressions. EXPR_P + points to the expression to gimplify. + + Expressions of the form 'a && b' are gimplified to: + + a && b ? true : false + + gimplify_cond_expr will do the rest. + + PRE_P points to the list where side effects that must happen before + *EXPR_P should be stored. */ + +static enum gimplify_status +gimplify_boolean_expr (tree *expr_p) +{ + /* Preserve the original type of the expression. */ + tree type = TREE_TYPE (*expr_p); + + *expr_p = build3 (COND_EXPR, type, *expr_p, + fold_convert (type, boolean_true_node), + fold_convert (type, boolean_false_node)); + + return GS_OK; +} + +/* Gimplifies an expression sequence. This function gimplifies each + expression and re-writes the original expression with the last + expression of the sequence in GIMPLE form. + + PRE_P points to the list where the side effects for all the + expressions in the sequence will be emitted. + + WANT_VALUE is true when the result of the last COMPOUND_EXPR is used. */ +/* ??? Should rearrange to share the pre-queue with all the indirect + invocations of gimplify_expr. Would probably save on creations + of statement_list nodes. */ + +static enum gimplify_status +gimplify_compound_expr (tree *expr_p, tree *pre_p, bool want_value) +{ + tree t = *expr_p; + + do + { + tree *sub_p = &TREE_OPERAND (t, 0); + + if (TREE_CODE (*sub_p) == COMPOUND_EXPR) + gimplify_compound_expr (sub_p, pre_p, false); + else + gimplify_stmt (sub_p); + append_to_statement_list (*sub_p, pre_p); + + t = TREE_OPERAND (t, 1); + } + while (TREE_CODE (t) == COMPOUND_EXPR); + + *expr_p = t; + if (want_value) + return GS_OK; + else + { + gimplify_stmt (expr_p); + return GS_ALL_DONE; + } +} + +/* Gimplifies a statement list. These may be created either by an + enlightened front-end, or by shortcut_cond_expr. */ + +static enum gimplify_status +gimplify_statement_list (tree *expr_p, tree *pre_p) +{ + tree temp = voidify_wrapper_expr (*expr_p, NULL); + + tree_stmt_iterator i = tsi_start (*expr_p); + + while (!tsi_end_p (i)) + { + tree t; + + gimplify_stmt (tsi_stmt_ptr (i)); + + t = tsi_stmt (i); + if (t == NULL) + tsi_delink (&i); + else if (TREE_CODE (t) == STATEMENT_LIST) + { + tsi_link_before (&i, t, TSI_SAME_STMT); + tsi_delink (&i); + } + else + tsi_next (&i); + } + + if (temp) + { + append_to_statement_list (*expr_p, pre_p); + *expr_p = temp; + return GS_OK; + } + + return GS_ALL_DONE; +} + +/* Gimplify a SAVE_EXPR node. EXPR_P points to the expression to + gimplify. After gimplification, EXPR_P will point to a new temporary + that holds the original value of the SAVE_EXPR node. + + PRE_P points to the list where side effects that must happen before + *EXPR_P should be stored. */ + +static enum gimplify_status +gimplify_save_expr (tree *expr_p, tree *pre_p, tree *post_p) +{ + enum gimplify_status ret = GS_ALL_DONE; + tree val; + + gcc_assert (TREE_CODE (*expr_p) == SAVE_EXPR); + val = TREE_OPERAND (*expr_p, 0); + + /* If the SAVE_EXPR has not been resolved, then evaluate it once. */ + if (!SAVE_EXPR_RESOLVED_P (*expr_p)) + { + /* The operand may be a void-valued expression such as SAVE_EXPRs + generated by the Java frontend for class initialization. It is + being executed only for its side-effects. */ + if (TREE_TYPE (val) == void_type_node) + { + ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p, + is_gimple_stmt, fb_none); + append_to_statement_list (TREE_OPERAND (*expr_p, 0), pre_p); + val = NULL; + } + else + val = get_initialized_tmp_var (val, pre_p, post_p); + + TREE_OPERAND (*expr_p, 0) = val; + SAVE_EXPR_RESOLVED_P (*expr_p) = 1; + } + + *expr_p = val; + + return ret; +} + +/* Re-write the ADDR_EXPR node pointed to by EXPR_P + + unary_expr + : ... + | '&' varname + ... + + PRE_P points to the list where side effects that must happen before + *EXPR_P should be stored. + + POST_P points to the list where side effects that must happen after + *EXPR_P should be stored. */ + +static enum gimplify_status +gimplify_addr_expr (tree *expr_p, tree *pre_p, tree *post_p) +{ + tree expr = *expr_p; + tree op0 = TREE_OPERAND (expr, 0); + enum gimplify_status ret; + + switch (TREE_CODE (op0)) + { + case INDIRECT_REF: + case MISALIGNED_INDIRECT_REF: + do_indirect_ref: + /* Check if we are dealing with an expression of the form '&*ptr'. + While the front end folds away '&*ptr' into 'ptr', these + expressions may be generated internally by the compiler (e.g., + builtins like __builtin_va_end). */ + /* Caution: the silent array decomposition semantics we allow for + ADDR_EXPR means we can't always discard the pair. */ + /* Gimplification of the ADDR_EXPR operand may drop + cv-qualification conversions, so make sure we add them if + needed. */ + { + tree op00 = TREE_OPERAND (op0, 0); + tree t_expr = TREE_TYPE (expr); + tree t_op00 = TREE_TYPE (op00); + + if (!lang_hooks.types_compatible_p (t_expr, t_op00)) + { +#ifdef ENABLE_CHECKING + tree t_op0 = TREE_TYPE (op0); + gcc_assert (POINTER_TYPE_P (t_expr) + && cpt_same_type (TREE_CODE (t_op0) == ARRAY_TYPE + ? TREE_TYPE (t_op0) : t_op0, + TREE_TYPE (t_expr)) + && POINTER_TYPE_P (t_op00) + && cpt_same_type (t_op0, TREE_TYPE (t_op00))); +#endif + op00 = fold_convert (TREE_TYPE (expr), op00); + } + *expr_p = op00; + ret = GS_OK; + } + break; + + case VIEW_CONVERT_EXPR: + /* Take the address of our operand and then convert it to the type of + this ADDR_EXPR. + + ??? The interactions of VIEW_CONVERT_EXPR and aliasing is not at + all clear. The impact of this transformation is even less clear. */ + + /* If the operand is a useless conversion, look through it. Doing so + guarantees that the ADDR_EXPR and its operand will remain of the + same type. */ + if (tree_ssa_useless_type_conversion (TREE_OPERAND (op0, 0))) + op0 = TREE_OPERAND (op0, 0); + + *expr_p = fold_convert (TREE_TYPE (expr), + build_fold_addr_expr (TREE_OPERAND (op0, 0))); + ret = GS_OK; + break; + + default: + /* We use fb_either here because the C frontend sometimes takes + the address of a call that returns a struct; see + gcc.dg/c99-array-lval-1.c. The gimplifier will correctly make + the implied temporary explicit. */ + ret = gimplify_expr (&TREE_OPERAND (expr, 0), pre_p, post_p, + is_gimple_addressable, fb_either); + if (ret != GS_ERROR) + { + op0 = TREE_OPERAND (expr, 0); + + /* For various reasons, the gimplification of the expression + may have made a new INDIRECT_REF. */ + if (TREE_CODE (op0) == INDIRECT_REF) + goto do_indirect_ref; + + /* Make sure TREE_INVARIANT, TREE_CONSTANT, and TREE_SIDE_EFFECTS + is set properly. */ + recompute_tree_invariant_for_addr_expr (expr); + + /* Mark the RHS addressable. */ + lang_hooks.mark_addressable (TREE_OPERAND (expr, 0)); + } + break; + } + + return ret; +} + +/* Gimplify the operands of an ASM_EXPR. Input operands should be a gimple + value; output operands should be a gimple lvalue. */ + +static enum gimplify_status +gimplify_asm_expr (tree *expr_p, tree *pre_p, tree *post_p) +{ + tree expr = *expr_p; + int noutputs = list_length (ASM_OUTPUTS (expr)); + const char **oconstraints + = (const char **) alloca ((noutputs) * sizeof (const char *)); + int i; + tree link; + const char *constraint; + bool allows_mem, allows_reg, is_inout; + enum gimplify_status ret, tret; + + ret = GS_ALL_DONE; + for (i = 0, link = ASM_OUTPUTS (expr); link; ++i, link = TREE_CHAIN (link)) + { + size_t constraint_len; + oconstraints[i] = constraint + = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); + constraint_len = strlen (constraint); + if (constraint_len == 0) + continue; + + parse_output_constraint (&constraint, i, 0, 0, + &allows_mem, &allows_reg, &is_inout); + + if (!allows_reg && allows_mem) + lang_hooks.mark_addressable (TREE_VALUE (link)); + + tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p, + is_inout ? is_gimple_min_lval : is_gimple_lvalue, + fb_lvalue | fb_mayfail); + if (tret == GS_ERROR) + { + error ("invalid lvalue in asm output %d", i); + ret = tret; + } + + if (is_inout) + { + /* An input/output operand. To give the optimizers more + flexibility, split it into separate input and output + operands. */ + tree input; + char buf[10]; + + /* Turn the in/out constraint into an output constraint. */ + char *p = xstrdup (constraint); + p[0] = '='; + TREE_VALUE (TREE_PURPOSE (link)) = build_string (constraint_len, p); + + /* And add a matching input constraint. */ + if (allows_reg) + { + sprintf (buf, "%d", i); + + /* If there are multiple alternatives in the constraint, + handle each of them individually. Those that allow register + will be replaced with operand number, the others will stay + unchanged. */ + if (strchr (p, ',') != NULL) + { + size_t len = 0, buflen = strlen (buf); + char *beg, *end, *str, *dst; + + for (beg = p + 1;;) + { + end = strchr (beg, ','); + if (end == NULL) + end = strchr (beg, '\0'); + if ((size_t) (end - beg) < buflen) + len += buflen + 1; + else + len += end - beg + 1; + if (*end) + beg = end + 1; + else + break; + } + + str = (char *) alloca (len); + for (beg = p + 1, dst = str;;) + { + const char *tem; + bool mem_p, reg_p, inout_p; + + end = strchr (beg, ','); + if (end) + *end = '\0'; + beg[-1] = '='; + tem = beg - 1; + parse_output_constraint (&tem, i, 0, 0, + &mem_p, ®_p, &inout_p); + if (dst != str) + *dst++ = ','; + if (reg_p) + { + memcpy (dst, buf, buflen); + dst += buflen; + } + else + { + if (end) + len = end - beg; + else + len = strlen (beg); + memcpy (dst, beg, len); + dst += len; + } + if (end) + beg = end + 1; + else + break; + } + *dst = '\0'; + input = build_string (dst - str, str); + } + else + input = build_string (strlen (buf), buf); + } + else + input = build_string (constraint_len - 1, constraint + 1); + + free (p); + + input = build_tree_list (build_tree_list (NULL_TREE, input), + unshare_expr (TREE_VALUE (link))); + ASM_INPUTS (expr) = chainon (ASM_INPUTS (expr), input); + } + } + + for (link = ASM_INPUTS (expr); link; ++i, link = TREE_CHAIN (link)) + { + constraint + = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); + parse_input_constraint (&constraint, 0, 0, noutputs, 0, + oconstraints, &allows_mem, &allows_reg); + + /* If we can't make copies, we can only accept memory. */ + if (TREE_ADDRESSABLE (TREE_TYPE (TREE_VALUE (link)))) + { + if (allows_mem) + allows_reg = 0; + else + { + error ("impossible constraint in %<asm%>"); + error ("non-memory input %d must stay in memory", i); + return GS_ERROR; + } + } + + /* If the operand is a memory input, it should be an lvalue. */ + if (!allows_reg && allows_mem) + { + tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p, + is_gimple_lvalue, fb_lvalue | fb_mayfail); + lang_hooks.mark_addressable (TREE_VALUE (link)); + if (tret == GS_ERROR) + { + error ("memory input %d is not directly addressable", i); + ret = tret; + } + } + else + { + tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p, + is_gimple_asm_val, fb_rvalue); + if (tret == GS_ERROR) + ret = tret; + } + } + + return ret; +} + +/* Gimplify a CLEANUP_POINT_EXPR. Currently this works by adding + WITH_CLEANUP_EXPRs to the prequeue as we encounter cleanups while + gimplifying the body, and converting them to TRY_FINALLY_EXPRs when we + return to this function. + + FIXME should we complexify the prequeue handling instead? Or use flags + for all the cleanups and let the optimizer tighten them up? The current + code seems pretty fragile; it will break on a cleanup within any + non-conditional nesting. But any such nesting would be broken, anyway; + we can't write a TRY_FINALLY_EXPR that starts inside a nesting construct + and continues out of it. We can do that at the RTL level, though, so + having an optimizer to tighten up try/finally regions would be a Good + Thing. */ + +static enum gimplify_status +gimplify_cleanup_point_expr (tree *expr_p, tree *pre_p) +{ + tree_stmt_iterator iter; + tree body; + + tree temp = voidify_wrapper_expr (*expr_p, NULL); + + /* We only care about the number of conditions between the innermost + CLEANUP_POINT_EXPR and the cleanup. So save and reset the count and + any cleanups collected outside the CLEANUP_POINT_EXPR. */ + int old_conds = gimplify_ctxp->conditions; + tree old_cleanups = gimplify_ctxp->conditional_cleanups; + gimplify_ctxp->conditions = 0; + gimplify_ctxp->conditional_cleanups = NULL_TREE; + + body = TREE_OPERAND (*expr_p, 0); + gimplify_to_stmt_list (&body); + + gimplify_ctxp->conditions = old_conds; + gimplify_ctxp->conditional_cleanups = old_cleanups; + + for (iter = tsi_start (body); !tsi_end_p (iter); ) + { + tree *wce_p = tsi_stmt_ptr (iter); + tree wce = *wce_p; + + if (TREE_CODE (wce) == WITH_CLEANUP_EXPR) + { + if (tsi_one_before_end_p (iter)) + { + tsi_link_before (&iter, TREE_OPERAND (wce, 0), TSI_SAME_STMT); + tsi_delink (&iter); + break; + } + else + { + tree sl, tfe; + enum tree_code code; + + if (CLEANUP_EH_ONLY (wce)) + code = TRY_CATCH_EXPR; + else + code = TRY_FINALLY_EXPR; + + sl = tsi_split_statement_list_after (&iter); + tfe = build2 (code, void_type_node, sl, NULL_TREE); + append_to_statement_list (TREE_OPERAND (wce, 0), + &TREE_OPERAND (tfe, 1)); + *wce_p = tfe; + iter = tsi_start (sl); + } + } + else + tsi_next (&iter); + } + + if (temp) + { + *expr_p = temp; + append_to_statement_list (body, pre_p); + return GS_OK; + } + else + { + *expr_p = body; + return GS_ALL_DONE; + } +} + +/* Insert a cleanup marker for gimplify_cleanup_point_expr. CLEANUP + is the cleanup action required. */ + +static void +gimple_push_cleanup (tree var, tree cleanup, bool eh_only, tree *pre_p) +{ + tree wce; + + /* Errors can result in improperly nested cleanups. Which results in + confusion when trying to resolve the WITH_CLEANUP_EXPR. */ + if (errorcount || sorrycount) + return; + + if (gimple_conditional_context ()) + { + /* If we're in a conditional context, this is more complex. We only + want to run the cleanup if we actually ran the initialization that + necessitates it, but we want to run it after the end of the + conditional context. So we wrap the try/finally around the + condition and use a flag to determine whether or not to actually + run the destructor. Thus + + test ? f(A()) : 0 + + becomes (approximately) + + flag = 0; + try { + if (test) { A::A(temp); flag = 1; val = f(temp); } + else { val = 0; } + } finally { + if (flag) A::~A(temp); + } + val + */ + + tree flag = create_tmp_var (boolean_type_node, "cleanup"); + tree ffalse = build2 (MODIFY_EXPR, void_type_node, flag, + boolean_false_node); + tree ftrue = build2 (MODIFY_EXPR, void_type_node, flag, + boolean_true_node); + cleanup = build3 (COND_EXPR, void_type_node, flag, cleanup, NULL); + wce = build1 (WITH_CLEANUP_EXPR, void_type_node, cleanup); + append_to_statement_list (ffalse, &gimplify_ctxp->conditional_cleanups); + append_to_statement_list (wce, &gimplify_ctxp->conditional_cleanups); + append_to_statement_list (ftrue, pre_p); + + /* Because of this manipulation, and the EH edges that jump + threading cannot redirect, the temporary (VAR) will appear + to be used uninitialized. Don't warn. */ + TREE_NO_WARNING (var) = 1; + } + else + { + wce = build1 (WITH_CLEANUP_EXPR, void_type_node, cleanup); + CLEANUP_EH_ONLY (wce) = eh_only; + append_to_statement_list (wce, pre_p); + } + + gimplify_stmt (&TREE_OPERAND (wce, 0)); +} + +/* Gimplify a TARGET_EXPR which doesn't appear on the rhs of an INIT_EXPR. */ + +static enum gimplify_status +gimplify_target_expr (tree *expr_p, tree *pre_p, tree *post_p) +{ + tree targ = *expr_p; + tree temp = TARGET_EXPR_SLOT (targ); + tree init = TARGET_EXPR_INITIAL (targ); + enum gimplify_status ret; + + if (init) + { + /* TARGET_EXPR temps aren't part of the enclosing block, so add it + to the temps list. */ + gimple_add_tmp_var (temp); + + /* If TARGET_EXPR_INITIAL is void, then the mere evaluation of the + expression is supposed to initialize the slot. */ + if (VOID_TYPE_P (TREE_TYPE (init))) + ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, fb_none); + else + { + init = build2 (INIT_EXPR, void_type_node, temp, init); + ret = gimplify_expr (&init, pre_p, post_p, is_gimple_stmt, + fb_none); + } + if (ret == GS_ERROR) + { + /* PR c++/28266 Make sure this is expanded only once. */ + TARGET_EXPR_INITIAL (targ) = NULL_TREE; + return GS_ERROR; + } + append_to_statement_list (init, pre_p); + + /* If needed, push the cleanup for the temp. */ + if (TARGET_EXPR_CLEANUP (targ)) + { + gimplify_stmt (&TARGET_EXPR_CLEANUP (targ)); + gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ), + CLEANUP_EH_ONLY (targ), pre_p); + } + + /* Only expand this once. */ + TREE_OPERAND (targ, 3) = init; + TARGET_EXPR_INITIAL (targ) = NULL_TREE; + } + else + /* We should have expanded this before. */ + gcc_assert (DECL_SEEN_IN_BIND_EXPR_P (temp)); + + *expr_p = temp; + return GS_OK; +} + +/* Gimplification of expression trees. */ + +/* Gimplify an expression which appears at statement context; usually, this + means replacing it with a suitably gimple STATEMENT_LIST. */ + +void +gimplify_stmt (tree *stmt_p) +{ + gimplify_expr (stmt_p, NULL, NULL, is_gimple_stmt, fb_none); +} + +/* Similarly, but force the result to be a STATEMENT_LIST. */ + +void +gimplify_to_stmt_list (tree *stmt_p) +{ + gimplify_stmt (stmt_p); + if (!*stmt_p) + *stmt_p = alloc_stmt_list (); + else if (TREE_CODE (*stmt_p) != STATEMENT_LIST) + { + tree t = *stmt_p; + *stmt_p = alloc_stmt_list (); + append_to_statement_list (t, stmt_p); + } +} + + +/* Add FIRSTPRIVATE entries for DECL in the OpenMP the surrounding parallels + to CTX. If entries already exist, force them to be some flavor of private. + If there is no enclosing parallel, do nothing. */ + +void +omp_firstprivatize_variable (struct gimplify_omp_ctx *ctx, tree decl) +{ + splay_tree_node n; + + if (decl == NULL || !DECL_P (decl)) + return; + + do + { + n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl); + if (n != NULL) + { + if (n->value & GOVD_SHARED) + n->value = GOVD_FIRSTPRIVATE | (n->value & GOVD_SEEN); + else + return; + } + else if (ctx->is_parallel) + omp_add_variable (ctx, decl, GOVD_FIRSTPRIVATE); + + ctx = ctx->outer_context; + } + while (ctx); +} + +/* Similarly for each of the type sizes of TYPE. */ + +static void +omp_firstprivatize_type_sizes (struct gimplify_omp_ctx *ctx, tree type) +{ + if (type == NULL || type == error_mark_node) + return; + type = TYPE_MAIN_VARIANT (type); + + if (pointer_set_insert (ctx->privatized_types, type)) + return; + + switch (TREE_CODE (type)) + { + case INTEGER_TYPE: + case ENUMERAL_TYPE: + case BOOLEAN_TYPE: + case REAL_TYPE: + omp_firstprivatize_variable (ctx, TYPE_MIN_VALUE (type)); + omp_firstprivatize_variable (ctx, TYPE_MAX_VALUE (type)); + break; + + case ARRAY_TYPE: + omp_firstprivatize_type_sizes (ctx, TREE_TYPE (type)); + omp_firstprivatize_type_sizes (ctx, TYPE_DOMAIN (type)); + break; + + case RECORD_TYPE: + case UNION_TYPE: + case QUAL_UNION_TYPE: + { + tree field; + for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) + if (TREE_CODE (field) == FIELD_DECL) + { + omp_firstprivatize_variable (ctx, DECL_FIELD_OFFSET (field)); + omp_firstprivatize_type_sizes (ctx, TREE_TYPE (field)); + } + } + break; + + case POINTER_TYPE: + case REFERENCE_TYPE: + omp_firstprivatize_type_sizes (ctx, TREE_TYPE (type)); + break; + + default: + break; + } + + omp_firstprivatize_variable (ctx, TYPE_SIZE (type)); + omp_firstprivatize_variable (ctx, TYPE_SIZE_UNIT (type)); + lang_hooks.types.omp_firstprivatize_type_sizes (ctx, type); +} + +/* Add an entry for DECL in the OpenMP context CTX with FLAGS. */ + +static void +omp_add_variable (struct gimplify_omp_ctx *ctx, tree decl, unsigned int flags) +{ + splay_tree_node n; + unsigned int nflags; + tree t; + + if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node) + return; + + /* Never elide decls whose type has TREE_ADDRESSABLE set. This means + there are constructors involved somewhere. */ + if (TREE_ADDRESSABLE (TREE_TYPE (decl)) + || TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl))) + flags |= GOVD_SEEN; + + n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl); + if (n != NULL) + { + /* We shouldn't be re-adding the decl with the same data + sharing class. */ + gcc_assert ((n->value & GOVD_DATA_SHARE_CLASS & flags) == 0); + /* The only combination of data sharing classes we should see is + FIRSTPRIVATE and LASTPRIVATE. */ + nflags = n->value | flags; + gcc_assert ((nflags & GOVD_DATA_SHARE_CLASS) + == (GOVD_FIRSTPRIVATE | GOVD_LASTPRIVATE)); + n->value = nflags; + return; + } + + /* When adding a variable-sized variable, we have to handle all sorts + of additional bits of data: the pointer replacement variable, and + the parameters of the type. */ + if (DECL_SIZE (decl) && TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST) + { + /* Add the pointer replacement variable as PRIVATE if the variable + replacement is private, else FIRSTPRIVATE since we'll need the + address of the original variable either for SHARED, or for the + copy into or out of the context. */ + if (!(flags & GOVD_LOCAL)) + { + nflags = flags & GOVD_PRIVATE ? GOVD_PRIVATE : GOVD_FIRSTPRIVATE; + nflags |= flags & GOVD_SEEN; + t = DECL_VALUE_EXPR (decl); + gcc_assert (TREE_CODE (t) == INDIRECT_REF); + t = TREE_OPERAND (t, 0); + gcc_assert (DECL_P (t)); + omp_add_variable (ctx, t, nflags); + } + + /* Add all of the variable and type parameters (which should have + been gimplified to a formal temporary) as FIRSTPRIVATE. */ + omp_firstprivatize_variable (ctx, DECL_SIZE_UNIT (decl)); + omp_firstprivatize_variable (ctx, DECL_SIZE (decl)); + omp_firstprivatize_type_sizes (ctx, TREE_TYPE (decl)); + + /* The variable-sized variable itself is never SHARED, only some form + of PRIVATE. The sharing would take place via the pointer variable + which we remapped above. */ + if (flags & GOVD_SHARED) + flags = GOVD_PRIVATE | GOVD_DEBUG_PRIVATE + | (flags & (GOVD_SEEN | GOVD_EXPLICIT)); + + /* We're going to make use of the TYPE_SIZE_UNIT at least in the + alloca statement we generate for the variable, so make sure it + is available. This isn't automatically needed for the SHARED + case, since we won't be allocating local storage then. + For local variables TYPE_SIZE_UNIT might not be gimplified yet, + in this case omp_notice_variable will be called later + on when it is gimplified. */ + else if (! (flags & GOVD_LOCAL)) + omp_notice_variable (ctx, TYPE_SIZE_UNIT (TREE_TYPE (decl)), true); + } + else if (lang_hooks.decls.omp_privatize_by_reference (decl)) + { + gcc_assert ((flags & GOVD_LOCAL) == 0); + omp_firstprivatize_type_sizes (ctx, TREE_TYPE (decl)); + + /* Similar to the direct variable sized case above, we'll need the + size of references being privatized. */ + if ((flags & GOVD_SHARED) == 0) + { + t = TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (decl))); + if (TREE_CODE (t) != INTEGER_CST) + omp_notice_variable (ctx, t, true); + } + } + + splay_tree_insert (ctx->variables, (splay_tree_key)decl, flags); +} + +/* Record the fact that DECL was used within the OpenMP context CTX. + IN_CODE is true when real code uses DECL, and false when we should + merely emit default(none) errors. Return true if DECL is going to + be remapped and thus DECL shouldn't be gimplified into its + DECL_VALUE_EXPR (if any). */ + +static bool +omp_notice_variable (struct gimplify_omp_ctx *ctx, tree decl, bool in_code) +{ + splay_tree_node n; + unsigned flags = in_code ? GOVD_SEEN : 0; + bool ret = false, shared; + + if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node) + return false; + + /* Threadprivate variables are predetermined. */ + if (is_global_var (decl)) + { + if (DECL_THREAD_LOCAL_P (decl)) + return false; + + if (DECL_HAS_VALUE_EXPR_P (decl)) + { + tree value = get_base_address (DECL_VALUE_EXPR (decl)); + + if (value && DECL_P (value) && DECL_THREAD_LOCAL_P (value)) + return false; + } + } + + n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl); + if (n == NULL) + { + enum omp_clause_default_kind default_kind, kind; + + if (!ctx->is_parallel) + goto do_outer; + + /* ??? Some compiler-generated variables (like SAVE_EXPRs) could be + remapped firstprivate instead of shared. To some extent this is + addressed in omp_firstprivatize_type_sizes, but not effectively. */ + default_kind = ctx->default_kind; + kind = lang_hooks.decls.omp_predetermined_sharing (decl); + if (kind != OMP_CLAUSE_DEFAULT_UNSPECIFIED) + default_kind = kind; + + switch (default_kind) + { + case OMP_CLAUSE_DEFAULT_NONE: + error ("%qs not specified in enclosing parallel", + IDENTIFIER_POINTER (DECL_NAME (decl))); + error ("%Henclosing parallel", &ctx->location); + /* FALLTHRU */ + case OMP_CLAUSE_DEFAULT_SHARED: + flags |= GOVD_SHARED; + break; + case OMP_CLAUSE_DEFAULT_PRIVATE: + flags |= GOVD_PRIVATE; + break; + default: + gcc_unreachable (); + } + + omp_add_variable (ctx, decl, flags); + + shared = (flags & GOVD_SHARED) != 0; + ret = lang_hooks.decls.omp_disregard_value_expr (decl, shared); + goto do_outer; + } + + shared = ((flags | n->value) & GOVD_SHARED) != 0; + ret = lang_hooks.decls.omp_disregard_value_expr (decl, shared); + + /* If nothing changed, there's nothing left to do. */ + if ((n->value & flags) == flags) + return ret; + flags |= n->value; + n->value = flags; + + do_outer: + /* If the variable is private in the current context, then we don't + need to propagate anything to an outer context. */ + if (flags & GOVD_PRIVATE) + return ret; + if (ctx->outer_context + && omp_notice_variable (ctx->outer_context, decl, in_code)) + return true; + return ret; +} + +/* Verify that DECL is private within CTX. If there's specific information + to the contrary in the innermost scope, generate an error. */ + +static bool +omp_is_private (struct gimplify_omp_ctx *ctx, tree decl) +{ + splay_tree_node n; + + n = splay_tree_lookup (ctx->variables, (splay_tree_key)decl); + if (n != NULL) + { + if (n->value & GOVD_SHARED) + { + if (ctx == gimplify_omp_ctxp) + { + error ("iteration variable %qs should be private", + IDENTIFIER_POINTER (DECL_NAME (decl))); + n->value = GOVD_PRIVATE; + return true; + } + else + return false; + } + else if ((n->value & GOVD_EXPLICIT) != 0 + && (ctx == gimplify_omp_ctxp + || (ctx->is_combined_parallel + && gimplify_omp_ctxp->outer_context == ctx))) + { + if ((n->value & GOVD_FIRSTPRIVATE) != 0) + error ("iteration variable %qs should not be firstprivate", + IDENTIFIER_POINTER (DECL_NAME (decl))); + else if ((n->value & GOVD_REDUCTION) != 0) + error ("iteration variable %qs should not be reduction", + IDENTIFIER_POINTER (DECL_NAME (decl))); + } + return true; + } + + if (ctx->is_parallel) + return false; + else if (ctx->outer_context) + return omp_is_private (ctx->outer_context, decl); + else + return !is_global_var (decl); +} + +/* Return true if DECL is private within a parallel region + that binds to the current construct's context or in parallel + region's REDUCTION clause. */ + +static bool +omp_check_private (struct gimplify_omp_ctx *ctx, tree decl) +{ + splay_tree_node n; + + do + { + ctx = ctx->outer_context; + if (ctx == NULL) + return !(is_global_var (decl) + /* References might be private, but might be shared too. */ + || lang_hooks.decls.omp_privatize_by_reference (decl)); + + n = splay_tree_lookup (ctx->variables, (splay_tree_key) decl); + if (n != NULL) + return (n->value & GOVD_SHARED) == 0; + } + while (!ctx->is_parallel); + return false; +} + +/* Scan the OpenMP clauses in *LIST_P, installing mappings into a new + and previous omp contexts. */ + +static void +gimplify_scan_omp_clauses (tree *list_p, tree *pre_p, bool in_parallel, + bool in_combined_parallel) +{ + struct gimplify_omp_ctx *ctx, *outer_ctx; + tree c; + + ctx = new_omp_context (in_parallel, in_combined_parallel); + outer_ctx = ctx->outer_context; + + while ((c = *list_p) != NULL) + { + enum gimplify_status gs; + bool remove = false; + bool notice_outer = true; + const char *check_non_private = NULL; + unsigned int flags; + tree decl; + + switch (OMP_CLAUSE_CODE (c)) + { + case OMP_CLAUSE_PRIVATE: + flags = GOVD_PRIVATE | GOVD_EXPLICIT; + notice_outer = false; + goto do_add; + case OMP_CLAUSE_SHARED: + flags = GOVD_SHARED | GOVD_EXPLICIT; + goto do_add; + case OMP_CLAUSE_FIRSTPRIVATE: + flags = GOVD_FIRSTPRIVATE | GOVD_EXPLICIT; + check_non_private = "firstprivate"; + goto do_add; + case OMP_CLAUSE_LASTPRIVATE: + flags = GOVD_LASTPRIVATE | GOVD_SEEN | GOVD_EXPLICIT; + check_non_private = "lastprivate"; + goto do_add; + case OMP_CLAUSE_REDUCTION: + flags = GOVD_REDUCTION | GOVD_SEEN | GOVD_EXPLICIT; + check_non_private = "reduction"; + goto do_add; + + do_add: + decl = OMP_CLAUSE_DECL (c); + if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node) + { + remove = true; + break; + } + omp_add_variable (ctx, decl, flags); + if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION + && OMP_CLAUSE_REDUCTION_PLACEHOLDER (c)) + { + omp_add_variable (ctx, OMP_CLAUSE_REDUCTION_PLACEHOLDER (c), + GOVD_LOCAL | GOVD_SEEN); + gimplify_omp_ctxp = ctx; + push_gimplify_context (); + gimplify_stmt (&OMP_CLAUSE_REDUCTION_INIT (c)); + pop_gimplify_context (OMP_CLAUSE_REDUCTION_INIT (c)); + push_gimplify_context (); + gimplify_stmt (&OMP_CLAUSE_REDUCTION_MERGE (c)); + pop_gimplify_context (OMP_CLAUSE_REDUCTION_MERGE (c)); + gimplify_omp_ctxp = outer_ctx; + } + if (notice_outer) + goto do_notice; + break; + + case OMP_CLAUSE_COPYIN: + case OMP_CLAUSE_COPYPRIVATE: + decl = OMP_CLAUSE_DECL (c); + if (decl == error_mark_node || TREE_TYPE (decl) == error_mark_node) + { + remove = true; + break; + } + do_notice: + if (outer_ctx) + omp_notice_variable (outer_ctx, decl, true); + if (check_non_private + && !in_parallel + && omp_check_private (ctx, decl)) + { + error ("%s variable %qs is private in outer context", + check_non_private, IDENTIFIER_POINTER (DECL_NAME (decl))); + remove = true; + } + break; + + case OMP_CLAUSE_IF: + OMP_CLAUSE_OPERAND (c, 0) + = gimple_boolify (OMP_CLAUSE_OPERAND (c, 0)); + /* Fall through. */ + + case OMP_CLAUSE_SCHEDULE: + case OMP_CLAUSE_NUM_THREADS: + gs = gimplify_expr (&OMP_CLAUSE_OPERAND (c, 0), pre_p, NULL, + is_gimple_val, fb_rvalue); + if (gs == GS_ERROR) + remove = true; + break; + + case OMP_CLAUSE_NOWAIT: + case OMP_CLAUSE_ORDERED: + break; + + case OMP_CLAUSE_DEFAULT: + ctx->default_kind = OMP_CLAUSE_DEFAULT_KIND (c); + break; + + default: + gcc_unreachable (); + } + + if (remove) + *list_p = OMP_CLAUSE_CHAIN (c); + else + list_p = &OMP_CLAUSE_CHAIN (c); + } + + gimplify_omp_ctxp = ctx; +} + +/* For all variables that were not actually used within the context, + remove PRIVATE, SHARED, and FIRSTPRIVATE clauses. */ + +static int +gimplify_adjust_omp_clauses_1 (splay_tree_node n, void *data) +{ + tree *list_p = (tree *) data; + tree decl = (tree) n->key; + unsigned flags = n->value; + enum omp_clause_code code; + tree clause; + bool private_debug; + + if (flags & (GOVD_EXPLICIT | GOVD_LOCAL)) + return 0; + if ((flags & GOVD_SEEN) == 0) + return 0; + if (flags & GOVD_DEBUG_PRIVATE) + { + gcc_assert ((flags & GOVD_DATA_SHARE_CLASS) == GOVD_PRIVATE); + private_debug = true; + } + else + private_debug + = lang_hooks.decls.omp_private_debug_clause (decl, + !!(flags & GOVD_SHARED)); + if (private_debug) + code = OMP_CLAUSE_PRIVATE; + else if (flags & GOVD_SHARED) + { + if (is_global_var (decl)) + { + struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp->outer_context; + while (ctx != NULL) + { + splay_tree_node on + = splay_tree_lookup (ctx->variables, (splay_tree_key) decl); + if (on && (on->value & (GOVD_FIRSTPRIVATE | GOVD_LASTPRIVATE + | GOVD_PRIVATE | GOVD_REDUCTION)) != 0) + break; + ctx = ctx->outer_context; + } + if (ctx == NULL) + return 0; + } + code = OMP_CLAUSE_SHARED; + } + else if (flags & GOVD_PRIVATE) + code = OMP_CLAUSE_PRIVATE; + else if (flags & GOVD_FIRSTPRIVATE) + code = OMP_CLAUSE_FIRSTPRIVATE; + else + gcc_unreachable (); + + clause = build_omp_clause (code); + OMP_CLAUSE_DECL (clause) = decl; + OMP_CLAUSE_CHAIN (clause) = *list_p; + if (private_debug) + OMP_CLAUSE_PRIVATE_DEBUG (clause) = 1; + *list_p = clause; + + return 0; +} + +static void +gimplify_adjust_omp_clauses (tree *list_p) +{ + struct gimplify_omp_ctx *ctx = gimplify_omp_ctxp; + tree c, decl; + + while ((c = *list_p) != NULL) + { + splay_tree_node n; + bool remove = false; + + switch (OMP_CLAUSE_CODE (c)) + { + case OMP_CLAUSE_PRIVATE: + case OMP_CLAUSE_SHARED: + case OMP_CLAUSE_FIRSTPRIVATE: + decl = OMP_CLAUSE_DECL (c); + n = splay_tree_lookup (ctx->variables, (splay_tree_key) decl); + remove = !(n->value & GOVD_SEEN); + if (! remove) + { + bool shared = OMP_CLAUSE_CODE (c) == OMP_CLAUSE_SHARED; + if ((n->value & GOVD_DEBUG_PRIVATE) + || lang_hooks.decls.omp_private_debug_clause (decl, shared)) + { + gcc_assert ((n->value & GOVD_DEBUG_PRIVATE) == 0 + || ((n->value & GOVD_DATA_SHARE_CLASS) + == GOVD_PRIVATE)); + OMP_CLAUSE_SET_CODE (c, OMP_CLAUSE_PRIVATE); + OMP_CLAUSE_PRIVATE_DEBUG (c) = 1; + } + } + break; + + case OMP_CLAUSE_LASTPRIVATE: + /* Make sure OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE is set to + accurately reflect the presence of a FIRSTPRIVATE clause. */ + decl = OMP_CLAUSE_DECL (c); + n = splay_tree_lookup (ctx->variables, (splay_tree_key) decl); + OMP_CLAUSE_LASTPRIVATE_FIRSTPRIVATE (c) + = (n->value & GOVD_FIRSTPRIVATE) != 0; + break; + + case OMP_CLAUSE_REDUCTION: + case OMP_CLAUSE_COPYIN: + case OMP_CLAUSE_COPYPRIVATE: + case OMP_CLAUSE_IF: + case OMP_CLAUSE_NUM_THREADS: + case OMP_CLAUSE_SCHEDULE: + case OMP_CLAUSE_NOWAIT: + case OMP_CLAUSE_ORDERED: + case OMP_CLAUSE_DEFAULT: + break; + + default: + gcc_unreachable (); + } + + if (remove) + *list_p = OMP_CLAUSE_CHAIN (c); + else + list_p = &OMP_CLAUSE_CHAIN (c); + } + + /* Add in any implicit data sharing. */ + splay_tree_foreach (ctx->variables, gimplify_adjust_omp_clauses_1, list_p); + + gimplify_omp_ctxp = ctx->outer_context; + delete_omp_context (ctx); +} + +/* Gimplify the contents of an OMP_PARALLEL statement. This involves + gimplification of the body, as well as scanning the body for used + variables. We need to do this scan now, because variable-sized + decls will be decomposed during gimplification. */ + +static enum gimplify_status +gimplify_omp_parallel (tree *expr_p, tree *pre_p) +{ + tree expr = *expr_p; + + gimplify_scan_omp_clauses (&OMP_PARALLEL_CLAUSES (expr), pre_p, true, + OMP_PARALLEL_COMBINED (expr)); + + push_gimplify_context (); + + gimplify_stmt (&OMP_PARALLEL_BODY (expr)); + + if (TREE_CODE (OMP_PARALLEL_BODY (expr)) == BIND_EXPR) + pop_gimplify_context (OMP_PARALLEL_BODY (expr)); + else + pop_gimplify_context (NULL_TREE); + + gimplify_adjust_omp_clauses (&OMP_PARALLEL_CLAUSES (expr)); + + return GS_ALL_DONE; +} + +/* Gimplify the gross structure of an OMP_FOR statement. */ + +static enum gimplify_status +gimplify_omp_for (tree *expr_p, tree *pre_p) +{ + tree for_stmt, decl, t; + enum gimplify_status ret = 0; + + for_stmt = *expr_p; + + gimplify_scan_omp_clauses (&OMP_FOR_CLAUSES (for_stmt), pre_p, false, false); + + t = OMP_FOR_INIT (for_stmt); + gcc_assert (TREE_CODE (t) == MODIFY_EXPR); + decl = TREE_OPERAND (t, 0); + gcc_assert (DECL_P (decl)); + gcc_assert (INTEGRAL_TYPE_P (TREE_TYPE (decl))); + + /* Make sure the iteration variable is private. */ + if (omp_is_private (gimplify_omp_ctxp, decl)) + omp_notice_variable (gimplify_omp_ctxp, decl, true); + else + omp_add_variable (gimplify_omp_ctxp, decl, GOVD_PRIVATE | GOVD_SEEN); + + ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt), + NULL, is_gimple_val, fb_rvalue); + + t = OMP_FOR_COND (for_stmt); + gcc_assert (COMPARISON_CLASS_P (t)); + gcc_assert (TREE_OPERAND (t, 0) == decl); + + ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt), + NULL, is_gimple_val, fb_rvalue); + + t = OMP_FOR_INCR (for_stmt); + switch (TREE_CODE (t)) + { + case PREINCREMENT_EXPR: + case POSTINCREMENT_EXPR: + t = build_int_cst (TREE_TYPE (decl), 1); + goto build_modify; + case PREDECREMENT_EXPR: + case POSTDECREMENT_EXPR: + t = build_int_cst (TREE_TYPE (decl), -1); + goto build_modify; + build_modify: + t = build2 (PLUS_EXPR, TREE_TYPE (decl), decl, t); + t = build2 (MODIFY_EXPR, void_type_node, decl, t); + OMP_FOR_INCR (for_stmt) = t; + break; + + case MODIFY_EXPR: + gcc_assert (TREE_OPERAND (t, 0) == decl); + t = TREE_OPERAND (t, 1); + switch (TREE_CODE (t)) + { + case PLUS_EXPR: + if (TREE_OPERAND (t, 1) == decl) + { + TREE_OPERAND (t, 1) = TREE_OPERAND (t, 0); + TREE_OPERAND (t, 0) = decl; + break; + } + case MINUS_EXPR: + gcc_assert (TREE_OPERAND (t, 0) == decl); + break; + default: + gcc_unreachable (); + } + + ret |= gimplify_expr (&TREE_OPERAND (t, 1), &OMP_FOR_PRE_BODY (for_stmt), + NULL, is_gimple_val, fb_rvalue); + break; + + default: + gcc_unreachable (); + } + + gimplify_to_stmt_list (&OMP_FOR_BODY (for_stmt)); + gimplify_adjust_omp_clauses (&OMP_FOR_CLAUSES (for_stmt)); + + return ret == GS_ALL_DONE ? GS_ALL_DONE : GS_ERROR; +} + +/* Gimplify the gross structure of other OpenMP worksharing constructs. + In particular, OMP_SECTIONS and OMP_SINGLE. */ + +static enum gimplify_status +gimplify_omp_workshare (tree *expr_p, tree *pre_p) +{ + tree stmt = *expr_p; + + gimplify_scan_omp_clauses (&OMP_CLAUSES (stmt), pre_p, false, false); + gimplify_to_stmt_list (&OMP_BODY (stmt)); + gimplify_adjust_omp_clauses (&OMP_CLAUSES (stmt)); + + return GS_ALL_DONE; +} + +/* A subroutine of gimplify_omp_atomic. The front end is supposed to have + stabilized the lhs of the atomic operation as *ADDR. Return true if + EXPR is this stabilized form. */ + +static bool +goa_lhs_expr_p (tree expr, tree addr) +{ + /* Also include casts to other type variants. The C front end is fond + of adding these for e.g. volatile variables. This is like + STRIP_TYPE_NOPS but includes the main variant lookup. */ + while ((TREE_CODE (expr) == NOP_EXPR + || TREE_CODE (expr) == CONVERT_EXPR + || TREE_CODE (expr) == NON_LVALUE_EXPR) + && TREE_OPERAND (expr, 0) != error_mark_node + && (TYPE_MAIN_VARIANT (TREE_TYPE (expr)) + == TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (expr, 0))))) + expr = TREE_OPERAND (expr, 0); + + if (TREE_CODE (expr) == INDIRECT_REF && TREE_OPERAND (expr, 0) == addr) + return true; + if (TREE_CODE (addr) == ADDR_EXPR && expr == TREE_OPERAND (addr, 0)) + return true; + return false; +} + +/* A subroutine of gimplify_omp_atomic. Attempt to implement the atomic + operation as a __sync_fetch_and_op builtin. INDEX is log2 of the + size of the data type, and thus usable to find the index of the builtin + decl. Returns GS_UNHANDLED if the expression is not of the proper form. */ + +static enum gimplify_status +gimplify_omp_atomic_fetch_op (tree *expr_p, tree addr, tree rhs, int index) +{ + enum built_in_function base; + tree decl, args, itype; + enum insn_code *optab; + + /* Check for one of the supported fetch-op operations. */ + switch (TREE_CODE (rhs)) + { + case PLUS_EXPR: + base = BUILT_IN_FETCH_AND_ADD_N; + optab = sync_add_optab; + break; + case MINUS_EXPR: + base = BUILT_IN_FETCH_AND_SUB_N; + optab = sync_add_optab; + break; + case BIT_AND_EXPR: + base = BUILT_IN_FETCH_AND_AND_N; + optab = sync_and_optab; + break; + case BIT_IOR_EXPR: + base = BUILT_IN_FETCH_AND_OR_N; + optab = sync_ior_optab; + break; + case BIT_XOR_EXPR: + base = BUILT_IN_FETCH_AND_XOR_N; + optab = sync_xor_optab; + break; + default: + return GS_UNHANDLED; + } + + /* Make sure the expression is of the proper form. */ + if (goa_lhs_expr_p (TREE_OPERAND (rhs, 0), addr)) + rhs = TREE_OPERAND (rhs, 1); + else if (commutative_tree_code (TREE_CODE (rhs)) + && goa_lhs_expr_p (TREE_OPERAND (rhs, 1), addr)) + rhs = TREE_OPERAND (rhs, 0); + else + return GS_UNHANDLED; + + decl = built_in_decls[base + index + 1]; + itype = TREE_TYPE (TREE_TYPE (decl)); + + if (optab[TYPE_MODE (itype)] == CODE_FOR_nothing) + return GS_UNHANDLED; + + args = tree_cons (NULL, fold_convert (itype, rhs), NULL); + args = tree_cons (NULL, addr, args); + *expr_p = build_function_call_expr (decl, args); + return GS_OK; +} + +/* A subroutine of gimplify_omp_atomic_pipeline. Walk *EXPR_P and replace + appearances of *LHS_ADDR with LHS_VAR. If an expression does not involve + the lhs, evaluate it into a temporary. Return 1 if the lhs appeared as + a subexpression, 0 if it did not, or -1 if an error was encountered. */ + +static int +goa_stabilize_expr (tree *expr_p, tree *pre_p, tree lhs_addr, tree lhs_var) +{ + tree expr = *expr_p; + int saw_lhs; + + if (goa_lhs_expr_p (expr, lhs_addr)) + { + *expr_p = lhs_var; + return 1; + } + if (is_gimple_val (expr)) + return 0; + + saw_lhs = 0; + switch (TREE_CODE_CLASS (TREE_CODE (expr))) + { + case tcc_binary: + saw_lhs |= goa_stabilize_expr (&TREE_OPERAND (expr, 1), pre_p, + lhs_addr, lhs_var); + case tcc_unary: + saw_lhs |= goa_stabilize_expr (&TREE_OPERAND (expr, 0), pre_p, + lhs_addr, lhs_var); + break; + default: + break; + } + + if (saw_lhs == 0) + { + enum gimplify_status gs; + gs = gimplify_expr (expr_p, pre_p, NULL, is_gimple_val, fb_rvalue); + if (gs != GS_ALL_DONE) + saw_lhs = -1; + } + + return saw_lhs; +} + +/* A subroutine of gimplify_omp_atomic. Implement the atomic operation as: + + oldval = *addr; + repeat: + newval = rhs; // with oldval replacing *addr in rhs + oldval = __sync_val_compare_and_swap (addr, oldval, newval); + if (oldval != newval) + goto repeat; + + INDEX is log2 of the size of the data type, and thus usable to find the + index of the builtin decl. */ + +static enum gimplify_status +gimplify_omp_atomic_pipeline (tree *expr_p, tree *pre_p, tree addr, + tree rhs, int index) +{ + tree oldval, oldival, oldival2, newval, newival, label; + tree type, itype, cmpxchg, args, x, iaddr; + + cmpxchg = built_in_decls[BUILT_IN_VAL_COMPARE_AND_SWAP_N + index + 1]; + type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (addr))); + itype = TREE_TYPE (TREE_TYPE (cmpxchg)); + + if (sync_compare_and_swap[TYPE_MODE (itype)] == CODE_FOR_nothing) + return GS_UNHANDLED; + + oldval = create_tmp_var (type, NULL); + newval = create_tmp_var (type, NULL); + + /* Precompute as much of RHS as possible. In the same walk, replace + occurrences of the lhs value with our temporary. */ + if (goa_stabilize_expr (&rhs, pre_p, addr, oldval) < 0) + return GS_ERROR; + + x = build_fold_indirect_ref (addr); + x = build2 (MODIFY_EXPR, void_type_node, oldval, x); + gimplify_and_add (x, pre_p); + + /* For floating-point values, we'll need to view-convert them to integers + so that we can perform the atomic compare and swap. Simplify the + following code by always setting up the "i"ntegral variables. */ + if (INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type)) + { + oldival = oldval; + newival = newval; + iaddr = addr; + } + else + { + oldival = create_tmp_var (itype, NULL); + newival = create_tmp_var (itype, NULL); + + x = build1 (VIEW_CONVERT_EXPR, itype, oldval); + x = build2 (MODIFY_EXPR, void_type_node, oldival, x); + gimplify_and_add (x, pre_p); + iaddr = fold_convert (build_pointer_type (itype), addr); + } + + oldival2 = create_tmp_var (itype, NULL); + + label = create_artificial_label (); + x = build1 (LABEL_EXPR, void_type_node, label); + gimplify_and_add (x, pre_p); + + x = build2 (MODIFY_EXPR, void_type_node, newval, rhs); + gimplify_and_add (x, pre_p); + + if (newval != newival) + { + x = build1 (VIEW_CONVERT_EXPR, itype, newval); + x = build2 (MODIFY_EXPR, void_type_node, newival, x); + gimplify_and_add (x, pre_p); + } + + x = build2 (MODIFY_EXPR, void_type_node, oldival2, + fold_convert (itype, oldival)); + gimplify_and_add (x, pre_p); + + args = tree_cons (NULL, fold_convert (itype, newival), NULL); + args = tree_cons (NULL, fold_convert (itype, oldival), args); + args = tree_cons (NULL, iaddr, args); + x = build_function_call_expr (cmpxchg, args); + if (oldval == oldival) + x = fold_convert (type, x); + x = build2 (MODIFY_EXPR, void_type_node, oldival, x); + gimplify_and_add (x, pre_p); + + /* For floating point, be prepared for the loop backedge. */ + if (oldval != oldival) + { + x = build1 (VIEW_CONVERT_EXPR, type, oldival); + x = build2 (MODIFY_EXPR, void_type_node, oldval, x); + gimplify_and_add (x, pre_p); + } + + /* Note that we always perform the comparison as an integer, even for + floating point. This allows the atomic operation to properly + succeed even with NaNs and -0.0. */ + x = build3 (COND_EXPR, void_type_node, + build2 (NE_EXPR, boolean_type_node, oldival, oldival2), + build1 (GOTO_EXPR, void_type_node, label), NULL); + gimplify_and_add (x, pre_p); + + *expr_p = NULL; + return GS_ALL_DONE; +} + +/* A subroutine of gimplify_omp_atomic. Implement the atomic operation as: + + GOMP_atomic_start (); + *addr = rhs; + GOMP_atomic_end (); + + The result is not globally atomic, but works so long as all parallel + references are within #pragma omp atomic directives. According to + responses received from omp@openmp.org, appears to be within spec. + Which makes sense, since that's how several other compilers handle + this situation as well. */ + +static enum gimplify_status +gimplify_omp_atomic_mutex (tree *expr_p, tree *pre_p, tree addr, tree rhs) +{ + tree t; + + t = built_in_decls[BUILT_IN_GOMP_ATOMIC_START]; + t = build_function_call_expr (t, NULL); + gimplify_and_add (t, pre_p); + + t = build_fold_indirect_ref (addr); + t = build2 (MODIFY_EXPR, void_type_node, t, rhs); + gimplify_and_add (t, pre_p); + + t = built_in_decls[BUILT_IN_GOMP_ATOMIC_END]; + t = build_function_call_expr (t, NULL); + gimplify_and_add (t, pre_p); + + *expr_p = NULL; + return GS_ALL_DONE; +} + +/* Gimplify an OMP_ATOMIC statement. */ + +static enum gimplify_status +gimplify_omp_atomic (tree *expr_p, tree *pre_p) +{ + tree addr = TREE_OPERAND (*expr_p, 0); + tree rhs = TREE_OPERAND (*expr_p, 1); + tree type = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (addr))); + HOST_WIDE_INT index; + + /* Make sure the type is one of the supported sizes. */ + index = tree_low_cst (TYPE_SIZE_UNIT (type), 1); + index = exact_log2 (index); + if (index >= 0 && index <= 4) + { + enum gimplify_status gs; + unsigned int align; + + if (DECL_P (TREE_OPERAND (addr, 0))) + align = DECL_ALIGN_UNIT (TREE_OPERAND (addr, 0)); + else if (TREE_CODE (TREE_OPERAND (addr, 0)) == COMPONENT_REF + && TREE_CODE (TREE_OPERAND (TREE_OPERAND (addr, 0), 1)) + == FIELD_DECL) + align = DECL_ALIGN_UNIT (TREE_OPERAND (TREE_OPERAND (addr, 0), 1)); + else + align = TYPE_ALIGN_UNIT (type); + + /* __sync builtins require strict data alignment. */ + if (exact_log2 (align) >= index) + { + /* When possible, use specialized atomic update functions. */ + if (INTEGRAL_TYPE_P (type) || POINTER_TYPE_P (type)) + { + gs = gimplify_omp_atomic_fetch_op (expr_p, addr, rhs, index); + if (gs != GS_UNHANDLED) + return gs; + } + + /* If we don't have specialized __sync builtins, try and implement + as a compare and swap loop. */ + gs = gimplify_omp_atomic_pipeline (expr_p, pre_p, addr, rhs, index); + if (gs != GS_UNHANDLED) + return gs; + } + } + + /* The ultimate fallback is wrapping the operation in a mutex. */ + return gimplify_omp_atomic_mutex (expr_p, pre_p, addr, rhs); +} + +/* Gimplifies the expression tree pointed to by EXPR_P. Return 0 if + gimplification failed. + + PRE_P points to the list where side effects that must happen before + EXPR should be stored. + + POST_P points to the list where side effects that must happen after + EXPR should be stored, or NULL if there is no suitable list. In + that case, we copy the result to a temporary, emit the + post-effects, and then return the temporary. + + GIMPLE_TEST_F points to a function that takes a tree T and + returns nonzero if T is in the GIMPLE form requested by the + caller. The GIMPLE predicates are in tree-gimple.c. + + This test is used twice. Before gimplification, the test is + invoked to determine whether *EXPR_P is already gimple enough. If + that fails, *EXPR_P is gimplified according to its code and + GIMPLE_TEST_F is called again. If the test still fails, then a new + temporary variable is created and assigned the value of the + gimplified expression. + + FALLBACK tells the function what sort of a temporary we want. If the 1 + bit is set, an rvalue is OK. If the 2 bit is set, an lvalue is OK. + If both are set, either is OK, but an lvalue is preferable. + + The return value is either GS_ERROR or GS_ALL_DONE, since this function + iterates until solution. */ + +enum gimplify_status +gimplify_expr (tree *expr_p, tree *pre_p, tree *post_p, + bool (* gimple_test_f) (tree), fallback_t fallback) +{ + tree tmp; + tree internal_pre = NULL_TREE; + tree internal_post = NULL_TREE; + tree save_expr; + int is_statement = (pre_p == NULL); + location_t saved_location; + enum gimplify_status ret; + + save_expr = *expr_p; + if (save_expr == NULL_TREE) + return GS_ALL_DONE; + + /* We used to check the predicate here and return immediately if it + succeeds. This is wrong; the design is for gimplification to be + idempotent, and for the predicates to only test for valid forms, not + whether they are fully simplified. */ + + /* Set up our internal queues if needed. */ + if (pre_p == NULL) + pre_p = &internal_pre; + if (post_p == NULL) + post_p = &internal_post; + + saved_location = input_location; + if (save_expr != error_mark_node + && EXPR_HAS_LOCATION (*expr_p)) + input_location = EXPR_LOCATION (*expr_p); + + /* Loop over the specific gimplifiers until the toplevel node + remains the same. */ + do + { + /* Strip away as many useless type conversions as possible + at the toplevel. */ + STRIP_USELESS_TYPE_CONVERSION (*expr_p); + + /* Remember the expr. */ + save_expr = *expr_p; + + /* Die, die, die, my darling. */ + if (save_expr == error_mark_node + || (TREE_TYPE (save_expr) + && TREE_TYPE (save_expr) == error_mark_node)) + { + ret = GS_ERROR; + break; + } + + /* Do any language-specific gimplification. */ + ret = lang_hooks.gimplify_expr (expr_p, pre_p, post_p); + if (ret == GS_OK) + { + if (*expr_p == NULL_TREE) + break; + if (*expr_p != save_expr) + continue; + } + else if (ret != GS_UNHANDLED) + break; + + ret = GS_OK; + switch (TREE_CODE (*expr_p)) + { + /* First deal with the special cases. */ + + case POSTINCREMENT_EXPR: + case POSTDECREMENT_EXPR: + case PREINCREMENT_EXPR: + case PREDECREMENT_EXPR: + ret = gimplify_self_mod_expr (expr_p, pre_p, post_p, + fallback != fb_none); + break; + + case ARRAY_REF: + case ARRAY_RANGE_REF: + case REALPART_EXPR: + case IMAGPART_EXPR: + case COMPONENT_REF: + case VIEW_CONVERT_EXPR: + ret = gimplify_compound_lval (expr_p, pre_p, post_p, + fallback ? fallback : fb_rvalue); + break; + + case COND_EXPR: + ret = gimplify_cond_expr (expr_p, pre_p, fallback); + /* C99 code may assign to an array in a structure value of a + conditional expression, and this has undefined behavior + only on execution, so create a temporary if an lvalue is + required. */ + if (fallback == fb_lvalue) + { + *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p); + lang_hooks.mark_addressable (*expr_p); + } + break; + + case CALL_EXPR: + ret = gimplify_call_expr (expr_p, pre_p, fallback != fb_none); + /* C99 code may assign to an array in a structure returned + from a function, and this has undefined behavior only on + execution, so create a temporary if an lvalue is + required. */ + if (fallback == fb_lvalue) + { + *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p); + lang_hooks.mark_addressable (*expr_p); + } + break; + + case TREE_LIST: + gcc_unreachable (); + + case COMPOUND_EXPR: + ret = gimplify_compound_expr (expr_p, pre_p, fallback != fb_none); + break; + + case MODIFY_EXPR: + case INIT_EXPR: + ret = gimplify_modify_expr (expr_p, pre_p, post_p, + fallback != fb_none); + + /* The distinction between MODIFY_EXPR and INIT_EXPR is no longer + useful. */ + if (*expr_p && TREE_CODE (*expr_p) == INIT_EXPR) + TREE_SET_CODE (*expr_p, MODIFY_EXPR); + break; + + case TRUTH_ANDIF_EXPR: + case TRUTH_ORIF_EXPR: + ret = gimplify_boolean_expr (expr_p); + break; + + case TRUTH_NOT_EXPR: + TREE_OPERAND (*expr_p, 0) + = gimple_boolify (TREE_OPERAND (*expr_p, 0)); + ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p, + is_gimple_val, fb_rvalue); + recalculate_side_effects (*expr_p); + break; + + case ADDR_EXPR: + ret = gimplify_addr_expr (expr_p, pre_p, post_p); + break; + + case VA_ARG_EXPR: + ret = gimplify_va_arg_expr (expr_p, pre_p, post_p); + break; + + case CONVERT_EXPR: + case NOP_EXPR: + if (IS_EMPTY_STMT (*expr_p)) + { + ret = GS_ALL_DONE; + break; + } + + if (VOID_TYPE_P (TREE_TYPE (*expr_p)) + || fallback == fb_none) + { + /* Just strip a conversion to void (or in void context) and + try again. */ + *expr_p = TREE_OPERAND (*expr_p, 0); + break; + } + + ret = gimplify_conversion (expr_p); + if (ret == GS_ERROR) + break; + if (*expr_p != save_expr) + break; + /* FALLTHRU */ + + case FIX_TRUNC_EXPR: + case FIX_CEIL_EXPR: + case FIX_FLOOR_EXPR: + case FIX_ROUND_EXPR: + /* unary_expr: ... | '(' cast ')' val | ... */ + ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p, + is_gimple_val, fb_rvalue); + recalculate_side_effects (*expr_p); + break; + + case INDIRECT_REF: + *expr_p = fold_indirect_ref (*expr_p); + if (*expr_p != save_expr) + break; + /* else fall through. */ + case ALIGN_INDIRECT_REF: + case MISALIGNED_INDIRECT_REF: + ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p, + is_gimple_reg, fb_rvalue); + recalculate_side_effects (*expr_p); + break; + + /* Constants need not be gimplified. */ + case INTEGER_CST: + case REAL_CST: + case STRING_CST: + case COMPLEX_CST: + case VECTOR_CST: + ret = GS_ALL_DONE; + break; + + case CONST_DECL: + /* If we require an lvalue, such as for ADDR_EXPR, retain the + CONST_DECL node. Otherwise the decl is replaceable by its + value. */ + /* ??? Should be == fb_lvalue, but ADDR_EXPR passes fb_either. */ + if (fallback & fb_lvalue) + ret = GS_ALL_DONE; + else + *expr_p = DECL_INITIAL (*expr_p); + break; + + case DECL_EXPR: + ret = gimplify_decl_expr (expr_p); + break; + + case EXC_PTR_EXPR: + /* FIXME make this a decl. */ + ret = GS_ALL_DONE; + break; + + case BIND_EXPR: + ret = gimplify_bind_expr (expr_p, pre_p); + break; + + case LOOP_EXPR: + ret = gimplify_loop_expr (expr_p, pre_p); + break; + + case SWITCH_EXPR: + ret = gimplify_switch_expr (expr_p, pre_p); + break; + + case EXIT_EXPR: + ret = gimplify_exit_expr (expr_p); + break; + + case GOTO_EXPR: + /* If the target is not LABEL, then it is a computed jump + and the target needs to be gimplified. */ + if (TREE_CODE (GOTO_DESTINATION (*expr_p)) != LABEL_DECL) + ret = gimplify_expr (&GOTO_DESTINATION (*expr_p), pre_p, + NULL, is_gimple_val, fb_rvalue); + break; + + case LABEL_EXPR: + ret = GS_ALL_DONE; + gcc_assert (decl_function_context (LABEL_EXPR_LABEL (*expr_p)) + == current_function_decl); + break; + + case CASE_LABEL_EXPR: + ret = gimplify_case_label_expr (expr_p); + break; + + case RETURN_EXPR: + ret = gimplify_return_expr (*expr_p, pre_p); + break; + + case CONSTRUCTOR: + /* Don't reduce this in place; let gimplify_init_constructor work its + magic. Buf if we're just elaborating this for side effects, just + gimplify any element that has side-effects. */ + if (fallback == fb_none) + { + unsigned HOST_WIDE_INT ix; + constructor_elt *ce; + tree temp = NULL_TREE; + for (ix = 0; + VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (*expr_p), + ix, ce); + ix++) + if (TREE_SIDE_EFFECTS (ce->value)) + append_to_statement_list (ce->value, &temp); + + *expr_p = temp; + ret = GS_OK; + } + /* C99 code may assign to an array in a constructed + structure or union, and this has undefined behavior only + on execution, so create a temporary if an lvalue is + required. */ + else if (fallback == fb_lvalue) + { + *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p); + lang_hooks.mark_addressable (*expr_p); + } + else + ret = GS_ALL_DONE; + break; + + /* The following are special cases that are not handled by the + original GIMPLE grammar. */ + + /* SAVE_EXPR nodes are converted into a GIMPLE identifier and + eliminated. */ + case SAVE_EXPR: + ret = gimplify_save_expr (expr_p, pre_p, post_p); + break; + + case BIT_FIELD_REF: + { + enum gimplify_status r0, r1, r2; + + r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p, + is_gimple_lvalue, fb_either); + r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p, + is_gimple_val, fb_rvalue); + r2 = gimplify_expr (&TREE_OPERAND (*expr_p, 2), pre_p, post_p, + is_gimple_val, fb_rvalue); + recalculate_side_effects (*expr_p); + + ret = MIN (r0, MIN (r1, r2)); + } + break; + + case NON_LVALUE_EXPR: + /* This should have been stripped above. */ + gcc_unreachable (); + + case ASM_EXPR: + ret = gimplify_asm_expr (expr_p, pre_p, post_p); + break; + + case TRY_FINALLY_EXPR: + case TRY_CATCH_EXPR: + gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 0)); + gimplify_to_stmt_list (&TREE_OPERAND (*expr_p, 1)); + ret = GS_ALL_DONE; + break; + + case CLEANUP_POINT_EXPR: + ret = gimplify_cleanup_point_expr (expr_p, pre_p); + break; + + case TARGET_EXPR: + ret = gimplify_target_expr (expr_p, pre_p, post_p); + break; + + case CATCH_EXPR: + gimplify_to_stmt_list (&CATCH_BODY (*expr_p)); + ret = GS_ALL_DONE; + break; + + case EH_FILTER_EXPR: + gimplify_to_stmt_list (&EH_FILTER_FAILURE (*expr_p)); + ret = GS_ALL_DONE; + break; + + case OBJ_TYPE_REF: + { + enum gimplify_status r0, r1; + r0 = gimplify_expr (&OBJ_TYPE_REF_OBJECT (*expr_p), pre_p, post_p, + is_gimple_val, fb_rvalue); + r1 = gimplify_expr (&OBJ_TYPE_REF_EXPR (*expr_p), pre_p, post_p, + is_gimple_val, fb_rvalue); + ret = MIN (r0, r1); + } + break; + + case LABEL_DECL: + /* We get here when taking the address of a label. We mark + the label as "forced"; meaning it can never be removed and + it is a potential target for any computed goto. */ + FORCED_LABEL (*expr_p) = 1; + ret = GS_ALL_DONE; + break; + + case STATEMENT_LIST: + ret = gimplify_statement_list (expr_p, pre_p); + break; + + case WITH_SIZE_EXPR: + { + gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, + post_p == &internal_post ? NULL : post_p, + gimple_test_f, fallback); + gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p, + is_gimple_val, fb_rvalue); + } + break; + + case VAR_DECL: + case PARM_DECL: + ret = gimplify_var_or_parm_decl (expr_p); + break; + + case RESULT_DECL: + /* When within an OpenMP context, notice uses of variables. */ + if (gimplify_omp_ctxp) + omp_notice_variable (gimplify_omp_ctxp, *expr_p, true); + ret = GS_ALL_DONE; + break; + + case SSA_NAME: + /* Allow callbacks into the gimplifier during optimization. */ + ret = GS_ALL_DONE; + break; + + case OMP_PARALLEL: + ret = gimplify_omp_parallel (expr_p, pre_p); + break; + + case OMP_FOR: + ret = gimplify_omp_for (expr_p, pre_p); + break; + + case OMP_SECTIONS: + case OMP_SINGLE: + ret = gimplify_omp_workshare (expr_p, pre_p); + break; + + case OMP_SECTION: + case OMP_MASTER: + case OMP_ORDERED: + case OMP_CRITICAL: + gimplify_to_stmt_list (&OMP_BODY (*expr_p)); + break; + + case OMP_ATOMIC: + ret = gimplify_omp_atomic (expr_p, pre_p); + break; + + case OMP_RETURN: + case OMP_CONTINUE: + ret = GS_ALL_DONE; + break; + + default: + switch (TREE_CODE_CLASS (TREE_CODE (*expr_p))) + { + case tcc_comparison: + /* Handle comparison of objects of non scalar mode aggregates + with a call to memcmp. It would be nice to only have to do + this for variable-sized objects, but then we'd have to allow + the same nest of reference nodes we allow for MODIFY_EXPR and + that's too complex. + + Compare scalar mode aggregates as scalar mode values. Using + memcmp for them would be very inefficient at best, and is + plain wrong if bitfields are involved. */ + + { + tree type = TREE_TYPE (TREE_OPERAND (*expr_p, 1)); + + if (!AGGREGATE_TYPE_P (type)) + goto expr_2; + else if (TYPE_MODE (type) != BLKmode) + ret = gimplify_scalar_mode_aggregate_compare (expr_p); + else + ret = gimplify_variable_sized_compare (expr_p); + + break; + } + + /* If *EXPR_P does not need to be special-cased, handle it + according to its class. */ + case tcc_unary: + ret = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, + post_p, is_gimple_val, fb_rvalue); + break; + + case tcc_binary: + expr_2: + { + enum gimplify_status r0, r1; + + r0 = gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, + post_p, is_gimple_val, fb_rvalue); + r1 = gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, + post_p, is_gimple_val, fb_rvalue); + + ret = MIN (r0, r1); + break; + } + + case tcc_declaration: + case tcc_constant: + ret = GS_ALL_DONE; + goto dont_recalculate; + + default: + gcc_assert (TREE_CODE (*expr_p) == TRUTH_AND_EXPR + || TREE_CODE (*expr_p) == TRUTH_OR_EXPR + || TREE_CODE (*expr_p) == TRUTH_XOR_EXPR); + goto expr_2; + } + + recalculate_side_effects (*expr_p); + dont_recalculate: + break; + } + + /* If we replaced *expr_p, gimplify again. */ + if (ret == GS_OK && (*expr_p == NULL || *expr_p == save_expr)) + ret = GS_ALL_DONE; + } + while (ret == GS_OK); + + /* If we encountered an error_mark somewhere nested inside, either + stub out the statement or propagate the error back out. */ + if (ret == GS_ERROR) + { + if (is_statement) + *expr_p = NULL; + goto out; + } + + /* This was only valid as a return value from the langhook, which + we handled. Make sure it doesn't escape from any other context. */ + gcc_assert (ret != GS_UNHANDLED); + + if (fallback == fb_none && *expr_p && !is_gimple_stmt (*expr_p)) + { + /* We aren't looking for a value, and we don't have a valid + statement. If it doesn't have side-effects, throw it away. */ + if (!TREE_SIDE_EFFECTS (*expr_p)) + *expr_p = NULL; + else if (!TREE_THIS_VOLATILE (*expr_p)) + { + /* This is probably a _REF that contains something nested that + has side effects. Recurse through the operands to find it. */ + enum tree_code code = TREE_CODE (*expr_p); + + switch (code) + { + case COMPONENT_REF: + case REALPART_EXPR: + case IMAGPART_EXPR: + case VIEW_CONVERT_EXPR: + gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p, + gimple_test_f, fallback); + break; + + case ARRAY_REF: + case ARRAY_RANGE_REF: + gimplify_expr (&TREE_OPERAND (*expr_p, 0), pre_p, post_p, + gimple_test_f, fallback); + gimplify_expr (&TREE_OPERAND (*expr_p, 1), pre_p, post_p, + gimple_test_f, fallback); + break; + + default: + /* Anything else with side-effects must be converted to + a valid statement before we get here. */ + gcc_unreachable (); + } + + *expr_p = NULL; + } + else if (COMPLETE_TYPE_P (TREE_TYPE (*expr_p)) + && TYPE_MODE (TREE_TYPE (*expr_p)) != BLKmode) + { + /* Historically, the compiler has treated a bare reference + to a non-BLKmode volatile lvalue as forcing a load. */ + tree type = TYPE_MAIN_VARIANT (TREE_TYPE (*expr_p)); + /* Normally, we do not want to create a temporary for a + TREE_ADDRESSABLE type because such a type should not be + copied by bitwise-assignment. However, we make an + exception here, as all we are doing here is ensuring that + we read the bytes that make up the type. We use + create_tmp_var_raw because create_tmp_var will abort when + given a TREE_ADDRESSABLE type. */ + tree tmp = create_tmp_var_raw (type, "vol"); + gimple_add_tmp_var (tmp); + *expr_p = build2 (MODIFY_EXPR, type, tmp, *expr_p); + } + else + /* We can't do anything useful with a volatile reference to + an incomplete type, so just throw it away. Likewise for + a BLKmode type, since any implicit inner load should + already have been turned into an explicit one by the + gimplification process. */ + *expr_p = NULL; + } + + /* If we are gimplifying at the statement level, we're done. Tack + everything together and replace the original statement with the + gimplified form. */ + if (fallback == fb_none || is_statement) + { + if (internal_pre || internal_post) + { + append_to_statement_list (*expr_p, &internal_pre); + append_to_statement_list (internal_post, &internal_pre); + annotate_all_with_locus (&internal_pre, input_location); + *expr_p = internal_pre; + } + else if (!*expr_p) + ; + else if (TREE_CODE (*expr_p) == STATEMENT_LIST) + annotate_all_with_locus (expr_p, input_location); + else + annotate_one_with_locus (*expr_p, input_location); + goto out; + } + + /* Otherwise we're gimplifying a subexpression, so the resulting value is + interesting. */ + + /* If it's sufficiently simple already, we're done. Unless we are + handling some post-effects internally; if that's the case, we need to + copy into a temp before adding the post-effects to the tree. */ + if (!internal_post && (*gimple_test_f) (*expr_p)) + goto out; + + /* Otherwise, we need to create a new temporary for the gimplified + expression. */ + + /* We can't return an lvalue if we have an internal postqueue. The + object the lvalue refers to would (probably) be modified by the + postqueue; we need to copy the value out first, which means an + rvalue. */ + if ((fallback & fb_lvalue) && !internal_post + && is_gimple_addressable (*expr_p)) + { + /* An lvalue will do. Take the address of the expression, store it + in a temporary, and replace the expression with an INDIRECT_REF of + that temporary. */ + tmp = build_fold_addr_expr (*expr_p); + gimplify_expr (&tmp, pre_p, post_p, is_gimple_reg, fb_rvalue); + *expr_p = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (tmp)), tmp); + } + else if ((fallback & fb_rvalue) && is_gimple_formal_tmp_rhs (*expr_p)) + { + gcc_assert (!VOID_TYPE_P (TREE_TYPE (*expr_p))); + + /* An rvalue will do. Assign the gimplified expression into a new + temporary TMP and replace the original expression with TMP. */ + + if (internal_post || (fallback & fb_lvalue)) + /* The postqueue might change the value of the expression between + the initialization and use of the temporary, so we can't use a + formal temp. FIXME do we care? */ + *expr_p = get_initialized_tmp_var (*expr_p, pre_p, post_p); + else + *expr_p = get_formal_tmp_var (*expr_p, pre_p); + + if (TREE_CODE (*expr_p) != SSA_NAME) + DECL_GIMPLE_FORMAL_TEMP_P (*expr_p) = 1; + } + else + { +#ifdef ENABLE_CHECKING + if (!(fallback & fb_mayfail)) + { + fprintf (stderr, "gimplification failed:\n"); + print_generic_expr (stderr, *expr_p, 0); + debug_tree (*expr_p); + internal_error ("gimplification failed"); + } +#endif + gcc_assert (fallback & fb_mayfail); + /* If this is an asm statement, and the user asked for the + impossible, don't die. Fail and let gimplify_asm_expr + issue an error. */ + ret = GS_ERROR; + goto out; + } + + /* Make sure the temporary matches our predicate. */ + gcc_assert ((*gimple_test_f) (*expr_p)); + + if (internal_post) + { + annotate_all_with_locus (&internal_post, input_location); + append_to_statement_list (internal_post, pre_p); + } + + out: + input_location = saved_location; + return ret; +} + +/* Look through TYPE for variable-sized objects and gimplify each such + size that we find. Add to LIST_P any statements generated. */ + +void +gimplify_type_sizes (tree type, tree *list_p) +{ + tree field, t; + + if (type == NULL || type == error_mark_node) + return; + + /* We first do the main variant, then copy into any other variants. */ + type = TYPE_MAIN_VARIANT (type); + + /* Avoid infinite recursion. */ + if (TYPE_SIZES_GIMPLIFIED (type)) + return; + + TYPE_SIZES_GIMPLIFIED (type) = 1; + + switch (TREE_CODE (type)) + { + case INTEGER_TYPE: + case ENUMERAL_TYPE: + case BOOLEAN_TYPE: + case REAL_TYPE: + gimplify_one_sizepos (&TYPE_MIN_VALUE (type), list_p); + gimplify_one_sizepos (&TYPE_MAX_VALUE (type), list_p); + + for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t)) + { + TYPE_MIN_VALUE (t) = TYPE_MIN_VALUE (type); + TYPE_MAX_VALUE (t) = TYPE_MAX_VALUE (type); + } + break; + + case ARRAY_TYPE: + /* These types may not have declarations, so handle them here. */ + gimplify_type_sizes (TREE_TYPE (type), list_p); + gimplify_type_sizes (TYPE_DOMAIN (type), list_p); + break; + + case RECORD_TYPE: + case UNION_TYPE: + case QUAL_UNION_TYPE: + for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) + if (TREE_CODE (field) == FIELD_DECL) + { + gimplify_one_sizepos (&DECL_FIELD_OFFSET (field), list_p); + gimplify_type_sizes (TREE_TYPE (field), list_p); + } + break; + + case POINTER_TYPE: + case REFERENCE_TYPE: + /* We used to recurse on the pointed-to type here, which turned out to + be incorrect because its definition might refer to variables not + yet initialized at this point if a forward declaration is involved. + + It was actually useful for anonymous pointed-to types to ensure + that the sizes evaluation dominates every possible later use of the + values. Restricting to such types here would be safe since there + is no possible forward declaration around, but would introduce an + undesirable middle-end semantic to anonymity. We then defer to + front-ends the responsibility of ensuring that the sizes are + evaluated both early and late enough, e.g. by attaching artificial + type declarations to the tree. */ + break; + + default: + break; + } + + gimplify_one_sizepos (&TYPE_SIZE (type), list_p); + gimplify_one_sizepos (&TYPE_SIZE_UNIT (type), list_p); + + for (t = TYPE_NEXT_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t)) + { + TYPE_SIZE (t) = TYPE_SIZE (type); + TYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (type); + TYPE_SIZES_GIMPLIFIED (t) = 1; + } +} + +/* A subroutine of gimplify_type_sizes to make sure that *EXPR_P, + a size or position, has had all of its SAVE_EXPRs evaluated. + We add any required statements to STMT_P. */ + +void +gimplify_one_sizepos (tree *expr_p, tree *stmt_p) +{ + tree type, expr = *expr_p; + + /* We don't do anything if the value isn't there, is constant, or contains + A PLACEHOLDER_EXPR. We also don't want to do anything if it's already + a VAR_DECL. If it's a VAR_DECL from another function, the gimplifier + will want to replace it with a new variable, but that will cause problems + if this type is from outside the function. It's OK to have that here. */ + if (expr == NULL_TREE || TREE_CONSTANT (expr) + || TREE_CODE (expr) == VAR_DECL + || CONTAINS_PLACEHOLDER_P (expr)) + return; + + type = TREE_TYPE (expr); + *expr_p = unshare_expr (expr); + + gimplify_expr (expr_p, stmt_p, NULL, is_gimple_val, fb_rvalue); + expr = *expr_p; + + /* Verify that we've an exact type match with the original expression. + In particular, we do not wish to drop a "sizetype" in favour of a + type of similar dimensions. We don't want to pollute the generic + type-stripping code with this knowledge because it doesn't matter + for the bulk of GENERIC/GIMPLE. It only matters that TYPE_SIZE_UNIT + and friends retain their "sizetype-ness". */ + if (TREE_TYPE (expr) != type + && TREE_CODE (type) == INTEGER_TYPE + && TYPE_IS_SIZETYPE (type)) + { + tree tmp; + + *expr_p = create_tmp_var (type, NULL); + tmp = build1 (NOP_EXPR, type, expr); + tmp = build2 (MODIFY_EXPR, type, *expr_p, tmp); + if (EXPR_HAS_LOCATION (expr)) + SET_EXPR_LOCUS (tmp, EXPR_LOCUS (expr)); + else + SET_EXPR_LOCATION (tmp, input_location); + + gimplify_and_add (tmp, stmt_p); + } +} + +#ifdef ENABLE_CHECKING +/* Compare types A and B for a "close enough" match. */ + +static bool +cpt_same_type (tree a, tree b) +{ + if (lang_hooks.types_compatible_p (a, b)) + return true; + + /* ??? The C++ FE decomposes METHOD_TYPES to FUNCTION_TYPES and doesn't + link them together. This routine is intended to catch type errors + that will affect the optimizers, and the optimizers don't add new + dereferences of function pointers, so ignore it. */ + if ((TREE_CODE (a) == FUNCTION_TYPE || TREE_CODE (a) == METHOD_TYPE) + && (TREE_CODE (b) == FUNCTION_TYPE || TREE_CODE (b) == METHOD_TYPE)) + return true; + + /* ??? The C FE pushes type qualifiers after the fact into the type of + the element from the type of the array. See build_unary_op's handling + of ADDR_EXPR. This seems wrong -- if we were going to do this, we + should have done it when creating the variable in the first place. + Alternately, why aren't the two array types made variants? */ + if (TREE_CODE (a) == ARRAY_TYPE && TREE_CODE (b) == ARRAY_TYPE) + return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b)); + + /* And because of those, we have to recurse down through pointers. */ + if (POINTER_TYPE_P (a) && POINTER_TYPE_P (b)) + return cpt_same_type (TREE_TYPE (a), TREE_TYPE (b)); + + return false; +} + +/* Check for some cases of the front end missing cast expressions. + The type of a dereference should correspond to the pointer type; + similarly the type of an address should match its object. */ + +static tree +check_pointer_types_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, + void *data ATTRIBUTE_UNUSED) +{ + tree t = *tp; + tree ptype, otype, dtype; + + switch (TREE_CODE (t)) + { + case INDIRECT_REF: + case ARRAY_REF: + otype = TREE_TYPE (t); + ptype = TREE_TYPE (TREE_OPERAND (t, 0)); + dtype = TREE_TYPE (ptype); + gcc_assert (cpt_same_type (otype, dtype)); + break; + + case ADDR_EXPR: + ptype = TREE_TYPE (t); + otype = TREE_TYPE (TREE_OPERAND (t, 0)); + dtype = TREE_TYPE (ptype); + if (!cpt_same_type (otype, dtype)) + { + /* &array is allowed to produce a pointer to the element, rather than + a pointer to the array type. We must allow this in order to + properly represent assigning the address of an array in C into + pointer to the element type. */ + gcc_assert (TREE_CODE (otype) == ARRAY_TYPE + && POINTER_TYPE_P (ptype) + && cpt_same_type (TREE_TYPE (otype), dtype)); + break; + } + break; + + default: + return NULL_TREE; + } + + + return NULL_TREE; +} +#endif + +/* Gimplify the body of statements pointed to by BODY_P. FNDECL is the + function decl containing BODY. */ + +void +gimplify_body (tree *body_p, tree fndecl, bool do_parms) +{ + location_t saved_location = input_location; + tree body, parm_stmts; + + timevar_push (TV_TREE_GIMPLIFY); + + gcc_assert (gimplify_ctxp == NULL); + push_gimplify_context (); + + /* Unshare most shared trees in the body and in that of any nested functions. + It would seem we don't have to do this for nested functions because + they are supposed to be output and then the outer function gimplified + first, but the g++ front end doesn't always do it that way. */ + unshare_body (body_p, fndecl); + unvisit_body (body_p, fndecl); + + /* Make sure input_location isn't set to something wierd. */ + input_location = DECL_SOURCE_LOCATION (fndecl); + + /* Resolve callee-copies. This has to be done before processing + the body so that DECL_VALUE_EXPR gets processed correctly. */ + parm_stmts = do_parms ? gimplify_parameters () : NULL; + + /* Gimplify the function's body. */ + gimplify_stmt (body_p); + body = *body_p; + + if (!body) + body = alloc_stmt_list (); + else if (TREE_CODE (body) == STATEMENT_LIST) + { + tree t = expr_only (*body_p); + if (t) + body = t; + } + + /* If there isn't an outer BIND_EXPR, add one. */ + if (TREE_CODE (body) != BIND_EXPR) + { + tree b = build3 (BIND_EXPR, void_type_node, NULL_TREE, + NULL_TREE, NULL_TREE); + TREE_SIDE_EFFECTS (b) = 1; + append_to_statement_list_force (body, &BIND_EXPR_BODY (b)); + body = b; + } + + /* If we had callee-copies statements, insert them at the beginning + of the function. */ + if (parm_stmts) + { + append_to_statement_list_force (BIND_EXPR_BODY (body), &parm_stmts); + BIND_EXPR_BODY (body) = parm_stmts; + } + + /* Unshare again, in case gimplification was sloppy. */ + unshare_all_trees (body); + + *body_p = body; + + pop_gimplify_context (body); + gcc_assert (gimplify_ctxp == NULL); + +#ifdef ENABLE_CHECKING + walk_tree (body_p, check_pointer_types_r, NULL, NULL); +#endif + + timevar_pop (TV_TREE_GIMPLIFY); + input_location = saved_location; +} + +/* Entry point to the gimplification pass. FNDECL is the FUNCTION_DECL + node for the function we want to gimplify. */ + +void +gimplify_function_tree (tree fndecl) +{ + tree oldfn, parm, ret; + + oldfn = current_function_decl; + current_function_decl = fndecl; + cfun = DECL_STRUCT_FUNCTION (fndecl); + if (cfun == NULL) + allocate_struct_function (fndecl); + + for (parm = DECL_ARGUMENTS (fndecl); parm ; parm = TREE_CHAIN (parm)) + { + /* Preliminarily mark non-addressed complex variables as eligible + for promotion to gimple registers. We'll transform their uses + as we find them. */ + if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE + && !TREE_THIS_VOLATILE (parm) + && !needs_to_live_in_memory (parm)) + DECL_COMPLEX_GIMPLE_REG_P (parm) = 1; + } + + ret = DECL_RESULT (fndecl); + if (TREE_CODE (TREE_TYPE (ret)) == COMPLEX_TYPE + && !needs_to_live_in_memory (ret)) + DECL_COMPLEX_GIMPLE_REG_P (ret) = 1; + + gimplify_body (&DECL_SAVED_TREE (fndecl), fndecl, true); + + /* If we're instrumenting function entry/exit, then prepend the call to + the entry hook and wrap the whole function in a TRY_FINALLY_EXPR to + catch the exit hook. */ + /* ??? Add some way to ignore exceptions for this TFE. */ + if (flag_instrument_function_entry_exit + && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl)) + { + tree tf, x, bind; + + tf = build2 (TRY_FINALLY_EXPR, void_type_node, NULL, NULL); + TREE_SIDE_EFFECTS (tf) = 1; + x = DECL_SAVED_TREE (fndecl); + append_to_statement_list (x, &TREE_OPERAND (tf, 0)); + x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_EXIT]; + x = build_function_call_expr (x, NULL); + append_to_statement_list (x, &TREE_OPERAND (tf, 1)); + + bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL); + TREE_SIDE_EFFECTS (bind) = 1; + x = implicit_built_in_decls[BUILT_IN_PROFILE_FUNC_ENTER]; + x = build_function_call_expr (x, NULL); + append_to_statement_list (x, &BIND_EXPR_BODY (bind)); + append_to_statement_list (tf, &BIND_EXPR_BODY (bind)); + + DECL_SAVED_TREE (fndecl) = bind; + } + + current_function_decl = oldfn; + cfun = oldfn ? DECL_STRUCT_FUNCTION (oldfn) : NULL; +} + + +/* Expands EXPR to list of gimple statements STMTS. If SIMPLE is true, + force the result to be either ssa_name or an invariant, otherwise + just force it to be a rhs expression. If VAR is not NULL, make the + base variable of the final destination be VAR if suitable. */ + +tree +force_gimple_operand (tree expr, tree *stmts, bool simple, tree var) +{ + tree t; + enum gimplify_status ret; + gimple_predicate gimple_test_f; + + *stmts = NULL_TREE; + + if (is_gimple_val (expr)) + return expr; + + gimple_test_f = simple ? is_gimple_val : is_gimple_reg_rhs; + + push_gimplify_context (); + gimplify_ctxp->into_ssa = in_ssa_p; + + if (var) + expr = build2 (MODIFY_EXPR, TREE_TYPE (var), var, expr); + + ret = gimplify_expr (&expr, stmts, NULL, + gimple_test_f, fb_rvalue); + gcc_assert (ret != GS_ERROR); + + if (referenced_vars) + { + for (t = gimplify_ctxp->temps; t ; t = TREE_CHAIN (t)) + add_referenced_var (t); + } + + pop_gimplify_context (NULL); + + return expr; +} + +/* Invokes force_gimple_operand for EXPR with parameters SIMPLE_P and VAR. If + some statements are produced, emits them before BSI. */ + +tree +force_gimple_operand_bsi (block_stmt_iterator *bsi, tree expr, + bool simple_p, tree var) +{ + tree stmts; + + expr = force_gimple_operand (expr, &stmts, simple_p, var); + if (stmts) + bsi_insert_before (bsi, stmts, BSI_SAME_STMT); + + return expr; +} + +#include "gt-gimplify.h" |
