diff options
Diffstat (limited to 'gnu/usr.bin/cc/cc1plus/gc.c')
| -rw-r--r-- | gnu/usr.bin/cc/cc1plus/gc.c | 988 |
1 files changed, 988 insertions, 0 deletions
diff --git a/gnu/usr.bin/cc/cc1plus/gc.c b/gnu/usr.bin/cc/cc1plus/gc.c new file mode 100644 index 0000000..9db4d62 --- /dev/null +++ b/gnu/usr.bin/cc/cc1plus/gc.c @@ -0,0 +1,988 @@ +/* Garbage collection primitives for GNU C++. + Copyright (C) 1992, 1993 Free Software Foundation, Inc. + Contributed by Michael Tiemann (tiemann@cygnus.com) + +This file is part of GNU CC. + +GNU CC 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. + +GNU CC 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 GNU CC; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + + +#include "config.h" +#include "tree.h" +#include "cp-tree.h" +#include "flags.h" + +#undef NULL +#define NULL 0 + +extern tree define_function (); +extern tree build_t_desc_overload (); + +/* This is the function decl for the (pseudo-builtin) __gc_protect + function. Args are (class *value, int index); Returns value. */ +tree gc_protect_fndecl; + +/* This is the function decl for the (pseudo-builtin) __gc_unprotect + function. Args are (int index); void return. */ +tree gc_unprotect_fndecl; + +/* This is the function decl for the (pseudo-builtin) __gc_push + function. Args are (int length); void return. */ +tree gc_push_fndecl; + +/* This is the function decl for the (pseudo-builtin) __gc_pop + function. Args are void; void return. */ +tree gc_pop_fndecl; + +/* Special integers that are used to represent bits in gc-safe objects. */ +tree gc_nonobject; +tree gc_visible; +tree gc_white; +tree gc_offwhite; +tree gc_grey; +tree gc_black; + +/* in c-common.c */ +extern tree combine_strings PROTO((tree)); + +/* Predicate that returns non-zero if TYPE needs some kind of + entry for the GC. Returns zero otherwise. */ +int +type_needs_gc_entry (type) + tree type; +{ + tree ttype = type; + + if (! flag_gc || type == error_mark_node) + return 0; + + /* Aggregate types need gc entries if any of their members + need gc entries. */ + if (IS_AGGR_TYPE (type)) + { + tree binfos; + tree fields = TYPE_FIELDS (type); + int i; + + /* We don't care about certain pointers. Pointers + to virtual baseclasses are always up front. We also + cull out virtual function table pointers because it's + easy, and it simplifies the logic.*/ + while (fields + && (DECL_NAME (fields) == NULL_TREE + || VFIELD_NAME_P (DECL_NAME (fields)) + || VBASE_NAME_P (DECL_NAME (fields)) + || !strcmp (IDENTIFIER_POINTER (DECL_NAME (fields)), "__bits"))) + fields = TREE_CHAIN (fields); + + while (fields) + { + if (type_needs_gc_entry (TREE_TYPE (fields))) + return 1; + fields = TREE_CHAIN (fields); + } + + binfos = TYPE_BINFO_BASETYPES (type); + if (binfos) + for (i = TREE_VEC_LENGTH (binfos)-1; i >= 0; i--) + if (type_needs_gc_entry (BINFO_TYPE (TREE_VEC_ELT (binfos, i)))) + return 1; + + return 0; + } + + while (TREE_CODE (ttype) == ARRAY_TYPE + && TREE_CODE (TREE_TYPE (ttype)) == ARRAY_TYPE) + ttype = TREE_TYPE (ttype); + if ((TREE_CODE (ttype) == POINTER_TYPE + || TREE_CODE (ttype) == ARRAY_TYPE + || TREE_CODE (ttype) == REFERENCE_TYPE) + && IS_AGGR_TYPE (TREE_TYPE (ttype)) + && CLASSTYPE_DOSSIER (TREE_TYPE (ttype))) + return 1; + + return 0; +} + +/* Predicate that returns non-zero iff FROM is safe from the GC. + + If TO is nonzero, it means we know that FROM is being stored + in TO, which make make it safe. */ +int +value_safe_from_gc (to, from) + tree to, from; +{ + /* First, return non-zero for easy cases: parameters, + static variables. */ + if (TREE_CODE (from) == PARM_DECL + || (TREE_CODE (from) == VAR_DECL + && TREE_STATIC (from))) + return 1; + + /* If something has its address taken, it cannot be + in the heap, so it doesn't need to be protected. */ + if (TREE_CODE (from) == ADDR_EXPR || TREE_REFERENCE_EXPR (from)) + return 1; + + /* If we are storing into a static variable, then what + we store will be safe from the gc. */ + if (to && TREE_CODE (to) == VAR_DECL + && TREE_STATIC (to)) + return 1; + + /* Now recurse on structure of FROM. */ + switch (TREE_CODE (from)) + { + case COMPONENT_REF: + /* These guys are special, and safe. */ + if (TREE_CODE (TREE_OPERAND (from, 1)) == FIELD_DECL + && (VFIELD_NAME_P (DECL_NAME (TREE_OPERAND (from, 1))) + || VBASE_NAME_P (DECL_NAME (TREE_OPERAND (from, 1))))) + return 1; + /* fall through... */ + case NOP_EXPR: + case CONVERT_EXPR: + case NON_LVALUE_EXPR: + case WITH_CLEANUP_EXPR: + case SAVE_EXPR: + case PREDECREMENT_EXPR: + case PREINCREMENT_EXPR: + case POSTDECREMENT_EXPR: + case POSTINCREMENT_EXPR: + if (value_safe_from_gc (to, TREE_OPERAND (from, 0))) + return 1; + break; + + case VAR_DECL: + case PARM_DECL: + /* We can safely pass these things as parameters to functions. */ + if (to == 0) + return 1; + + case ARRAY_REF: + case INDIRECT_REF: + case RESULT_DECL: + case OFFSET_REF: + case CALL_EXPR: + case METHOD_CALL_EXPR: + break; + + case COMPOUND_EXPR: + case TARGET_EXPR: + if (value_safe_from_gc (to, TREE_OPERAND (from, 1))) + return 1; + break; + + case COND_EXPR: + if (value_safe_from_gc (to, TREE_OPERAND (from, 1)) + && value_safe_from_gc (to, TREE_OPERAND (from, 2))) + return 1; + break; + + case PLUS_EXPR: + case MINUS_EXPR: + if ((type_needs_gc_entry (TREE_TYPE (TREE_OPERAND (from, 0))) + || value_safe_from_gc (to, TREE_OPERAND (from, 0))) + && (type_needs_gc_entry (TREE_TYPE (TREE_OPERAND (from, 1))) == 0 + || value_safe_from_gc (to, TREE_OPERAND (from, 1)))) + return 1; + break; + + case RTL_EXPR: + /* Every time we build an RTL_EXPR in the front-end, we must + ensure that everything in it is safe from the garbage collector. + ??? This has only been done for `build_new'. */ + return 1; + + default: + my_friendly_abort (41); + } + + if (to == 0) + return 0; + + /* FROM wasn't safe. But other properties of TO might make it safe. */ + switch (TREE_CODE (to)) + { + case VAR_DECL: + case PARM_DECL: + /* We already culled out static VAR_DECLs above. */ + return 0; + + case COMPONENT_REF: + /* These guys are special, and safe. */ + if (TREE_CODE (TREE_OPERAND (to, 1)) == FIELD_DECL + && (VFIELD_NAME_P (DECL_NAME (TREE_OPERAND (to, 1))) + || VBASE_NAME_P (DECL_NAME (TREE_OPERAND (to, 1))))) + return 1; + /* fall through... */ + + case NOP_EXPR: + case NON_LVALUE_EXPR: + case WITH_CLEANUP_EXPR: + case SAVE_EXPR: + case PREDECREMENT_EXPR: + case PREINCREMENT_EXPR: + case POSTDECREMENT_EXPR: + case POSTINCREMENT_EXPR: + return value_safe_from_gc (TREE_OPERAND (to, 0), from); + + case COMPOUND_EXPR: + case TARGET_EXPR: + return value_safe_from_gc (TREE_OPERAND (to, 1), from); + + case COND_EXPR: + return (value_safe_from_gc (TREE_OPERAND (to, 1), from) + && value_safe_from_gc (TREE_OPERAND (to, 2), from)); + + case INDIRECT_REF: + case ARRAY_REF: + /* This used to be 0, but our current restricted model + allows this to be 1. We'll never get arrays this way. */ + return 1; + + default: + my_friendly_abort (42); + } + + /* Catch-all case is that TO/FROM is not safe. */ + return 0; +} + +/* Function to build a static GC entry for DECL. TYPE is DECL's type. + + For objects of type `class *', this is just an entry in the + static vector __PTR_LIST__. + + For objects of type `class[]', this requires building an entry + in the static vector __ARR_LIST__. + + For aggregates, this records all fields of type `class *' + and `class[]' in the respective lists above. */ +void +build_static_gc_entry (decl, type) + tree decl; + tree type; +{ + /* Now, figure out what sort of entry to build. */ + if (TREE_CODE (type) == POINTER_TYPE + || TREE_CODE (type) == REFERENCE_TYPE) + assemble_gc_entry (IDENTIFIER_POINTER (DECL_NAME (decl))); + else if (TREE_CODE (type) == RECORD_TYPE) + { + tree ref = get_temp_name (build_reference_type (type), 1); + DECL_INITIAL (ref) = build1 (ADDR_EXPR, TREE_TYPE (ref), decl); + TREE_CONSTANT (DECL_INITIAL (ref)) = 1; + finish_decl (ref, DECL_INITIAL (ref), 0, 0); + } + else + { + /* Not yet implemented. + + Cons up a static variable that holds address and length info + and add that to ___ARR_LIST__. */ + my_friendly_abort (43); + } +} + +/* Protect FROM from the GC, assuming FROM is going to be + stored into TO. We handle three cases for TO here: + + case 1: TO is a stack variable. + case 2: TO is zero (which means it is a parameter). + case 3: TO is a return value. */ + +tree +protect_value_from_gc (to, from) + tree to, from; +{ + if (to == 0) + { + tree cleanup; + + to = get_temp_regvar (TREE_TYPE (from), from); + + /* Convert from integer to list form since we'll use it twice. */ + DECL_GC_OFFSET (to) = build_tree_list (NULL_TREE, DECL_GC_OFFSET (to)); + cleanup = build_function_call (gc_unprotect_fndecl, + DECL_GC_OFFSET (to)); + + if (! expand_decl_cleanup (to, cleanup)) + { + compiler_error ("cannot unprotect parameter in this scope"); + return error_mark_node; + } + } + + /* Should never need to protect a value that's headed for static storage. */ + if (TREE_STATIC (to)) + my_friendly_abort (44); + + switch (TREE_CODE (to)) + { + case COMPONENT_REF: + case INDIRECT_REF: + return protect_value_from_gc (TREE_OPERAND (to, 0), from); + + case VAR_DECL: + case PARM_DECL: + { + tree rval; + if (DECL_GC_OFFSET (to) == NULL_TREE) + { + /* Because of a cast or a conversion, we might stick + a value into a variable that would not normally + have a GC entry. */ + DECL_GC_OFFSET (to) = size_int (++current_function_obstack_index); + } + + if (TREE_CODE (DECL_GC_OFFSET (to)) != TREE_LIST) + { + DECL_GC_OFFSET (to) + = build_tree_list (NULL_TREE, DECL_GC_OFFSET (to)); + } + + current_function_obstack_usage = 1; + rval = build_function_call (gc_protect_fndecl, + tree_cons (NULL_TREE, from, + DECL_GC_OFFSET (to))); + TREE_TYPE (rval) = TREE_TYPE (from); + return rval; + } + } + + /* If we fall through the switch, assume we lost. */ + my_friendly_abort (45); + /* NOTREACHED */ + return NULL_TREE; +} + +/* Given the expression EXP of type `class *', return the head + of the object pointed to by EXP. */ +tree +build_headof (exp) + tree exp; +{ + tree type = TREE_TYPE (exp); + tree vptr, offset; + + if (TREE_CODE (type) != POINTER_TYPE) + { + error ("`headof' applied to non-pointer type"); + return error_mark_node; + } + + if (flag_vtable_thunks) + abort(); + + vptr = build1 (INDIRECT_REF, TYPE_POINTER_TO (vtable_entry_type), exp); + offset = build_component_ref (build_array_ref (vptr, integer_one_node), + get_identifier (VTABLE_DELTA_NAME), + NULL_TREE, 0); + return build (PLUS_EXPR, class_star_type_node, exp, + convert (integer_type_node, offset)); +} + +/* Given the expression EXP of type `class *', return the + type descriptor for the object pointed to by EXP. */ +tree +build_classof (exp) + tree exp; +{ + tree type = TREE_TYPE (exp); + tree vptr; + tree t_desc_entry; + + if (TREE_CODE (type) != POINTER_TYPE) + { + error ("`classof' applied to non-pointer type"); + return error_mark_node; + } + + vptr = build1 (INDIRECT_REF, TYPE_POINTER_TO (vtable_entry_type), exp); + t_desc_entry = build_component_ref (build_array_ref (vptr, integer_one_node), + get_identifier (VTABLE_PFN_NAME), + NULL_TREE, 0); + TREE_TYPE (t_desc_entry) = TYPE_POINTER_TO (__t_desc_type_node); + return t_desc_entry; +} + +/* Return the Type_info node associated with the expression EXP. If EXP is + a reference to a polymorphic class, return the dynamic type; otherwise + return the static type of the expression. */ +tree +build_typeid (exp) + tree exp; +{ + tree type; + + if (exp == error_mark_node) + return error_mark_node; + + type = TREE_TYPE (exp); + + /* if b is an instance of B, typeid(b) == typeid(B). Do this before + reference trickiness. */ + if (TREE_CODE (exp) == VAR_DECL && TREE_CODE (type) == RECORD_TYPE) + return get_typeid (type); + + /* Apply trivial conversion T -> T& for dereferenced ptrs. */ + if (TREE_CODE (type) == RECORD_TYPE) + type = build_reference_type (type); + + /* If exp is a reference to polymorphic type, get the real Type_info. */ + if (TREE_CODE (type) == REFERENCE_TYPE && TYPE_VIRTUAL_P (TREE_TYPE (type))) + { + /* build reference to Type_info from vtable. */ + + sorry ("finding Type_info for an object"); + return error_mark_node; + } + + /* otherwise return the Type_info for the static type of the expr. */ + return get_typeid (type); +} + +/* Return the Type_info object for TYPE, creating it if necessary. */ +tree +get_typeid (type) + tree type; +{ + if (type == error_mark_node) + return error_mark_node; + + /* Is it useful (and/or correct) to have different typeids for `T &' + and `T'? */ + if (TREE_CODE (type) == REFERENCE_TYPE) + type = TREE_TYPE (type); + + /* build reference to static Type_info */ +#if 1 + sorry ("finding Type_info for a type"); + return error_mark_node; +#else + register tree t = TYPE_TINFO (type); + + if (t) + return t; + + /* ... */ + +#endif +} + +/* Execute a dynamic cast, as described in section 5.2.6 of the 9/93 working + paper. */ +tree +build_dynamic_cast (type, expr) + tree type, expr; +{ + enum tree_code tc = TREE_CODE (type); + tree exprtype = TREE_TYPE (expr); + enum tree_code ec = TREE_CODE (exprtype); + tree retval; + + if (type == error_mark_node || expr == error_mark_node) + return error_mark_node; + + switch (tc) + { + case POINTER_TYPE: + if (TREE_TYPE (type) == void_type_node) + break; + /* else fall through */ + case REFERENCE_TYPE: + if (TREE_CODE (TREE_TYPE (type)) == RECORD_TYPE + && TYPE_SIZE (TREE_TYPE (type)) != NULL_TREE) + break; + /* else fall through */ + default: + cp_error ("`%#T' is not a valid type argument for dynamic_cast", type); + error ("(must be either pointer or reference to defined class or void *)"); + return error_mark_node; + } + + /* Apply trivial conversion T -> T& for dereferenced ptrs. */ + if (ec == RECORD_TYPE) + { + exprtype = build_reference_type (exprtype); + ec = REFERENCE_TYPE; + } + + /* the TREE_CODE of exprtype must match that of type. */ + if (ec != tc) + { + cp_error ("`%E' (of type `%#T') fails to be of %s type", expr, exprtype, + tc == POINTER_TYPE ? "pointer" : "reference"); + return error_mark_node; + } + + /* If *type is an unambiguous accessible base class of *exprtype, + convert statically. */ + { + int distance; + tree path; + + distance = get_base_distance (TREE_TYPE (type), TREE_TYPE (exprtype), 1, + &path); + if (distance >= 0) + return build_vbase_path (PLUS_EXPR, type, expr, path, 0); + } + + /* Otherwise *exprtype must be a polymorphic class (have a vtbl). */ + if (TYPE_VIRTUAL_P (TREE_TYPE (exprtype))) + { + /* if TYPE is `void *', return pointer to complete object. */ + if (tc == POINTER_TYPE && TREE_TYPE (type) == void_type_node) + { + /* if b is an object, dynamic_cast<void *>(&b) == (void *)&b. */ + if (TREE_CODE (expr) == ADDR_EXPR + && TREE_CODE (TREE_OPERAND (expr, 0)) == VAR_DECL + && TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == RECORD_TYPE) + return build1 (NOP_EXPR, type, expr); + + sorry ("finding pointer to complete object"); + return build1 (NOP_EXPR, type, expr); + } + else + { + tree retval; + + /* If we got here, we can't convert statically. Therefore, + dynamic_cast<D&>(b) (b an object) cannot succeed. */ + if (ec == REFERENCE_TYPE) + { + if (TREE_CODE (expr) == VAR_DECL + && TREE_CODE (TREE_TYPE (expr)) == RECORD_TYPE) + { + cp_warning ("dynamic_cast of `%#D' to `%#T' can never succeed", + expr, type); + /* cplus_expand_throw (Bad_cast_node); */ + sorry ("throwing Bad_cast"); + return error_mark_node; + } + } + /* Ditto for dynamic_cast<D*>(&b). */ + else if (TREE_CODE (expr) == ADDR_EXPR) + { + tree op = TREE_OPERAND (expr, 0); + if (TREE_CODE (op) == VAR_DECL + && TREE_CODE (TREE_TYPE (op)) == RECORD_TYPE) + { + cp_warning ("dynamic_cast of `%E' to `%#T' can never succeed", + expr, type); + retval = build_int_2 (0, 0); + TREE_TYPE (retval) = type; + return retval; + } + } + /* Build run-time conversion. */ + sorry ("run-time type conversion"); + retval = build_int_2 (0, 0); + TREE_TYPE (retval) = type; + return retval; + } + } + + cp_error ("cannot dynamic_cast `%E' (of type `%#T') to type `%#T'", + expr, exprtype, type); + return error_mark_node; +} + +/* Build and initialize various sorts of descriptors. Every descriptor + node has a name associated with it (the name created by mangling). + For this reason, we use the identifier as our access to the __*_desc + nodes, instead of sticking them directly in the types. Otherwise we + would burden all built-in types (and pointer types) with slots that + we don't necessarily want to use. + + For each descriptor we build, we build a variable that contains + the descriptor's information. When we need this info at runtime, + all we need is access to these variables. + + Note: these constructors always return the address of the descriptor + info, since that is simplest for their mutual interaction. */ + +static tree +build_generic_desc (decl, elems) + tree decl; + tree elems; +{ + tree init = build (CONSTRUCTOR, TREE_TYPE (decl), NULL_TREE, elems); + TREE_CONSTANT (init) = 1; + TREE_STATIC (init) = 1; + TREE_READONLY (init) = 1; + + DECL_INITIAL (decl) = init; + TREE_STATIC (decl) = 1; + layout_decl (decl, 0); + finish_decl (decl, init, 0, 0); + + return IDENTIFIER_AS_DESC (DECL_NAME (decl)); +} + +/* Build an initializer for a __t_desc node. So that we can take advantage + of recursion, we accept NULL for TYPE. + DEFINITION is greater than zero iff we must define the type descriptor + (as opposed to merely referencing it). 1 means treat according to + #pragma interface/#pragma implementation rules. 2 means define as + global and public, no matter what. */ +tree +build_t_desc (type, definition) + tree type; + int definition; +{ + tree tdecl; + tree tname, name_string; + tree elems, fields; + tree parents, vbases, offsets, ivars, methods, target_type; + int method_count = 0, field_count = 0; + + if (type == NULL_TREE) + return NULL_TREE; + + tname = build_t_desc_overload (type); + if (IDENTIFIER_AS_DESC (tname) + && (!definition || TREE_ASM_WRITTEN (IDENTIFIER_AS_DESC (tname)))) + return IDENTIFIER_AS_DESC (tname); + + tdecl = lookup_name (tname, 0); + if (tdecl == NULL_TREE) + { + tdecl = build_decl (VAR_DECL, tname, __t_desc_type_node); + DECL_EXTERNAL (tdecl) = 1; + TREE_PUBLIC (tdecl) = 1; + tdecl = pushdecl_top_level (tdecl); + } + /* If we previously defined it, return the defined result. */ + else if (definition && DECL_INITIAL (tdecl)) + return IDENTIFIER_AS_DESC (tname); + + if (definition) + { + tree taggr = type; + /* Let T* and T& be written only when T is written (if T is an aggr). + We do this for const, but not for volatile, since volatile + is rare and const is not. */ + if (!TYPE_VOLATILE (taggr) + && (TREE_CODE (taggr) == POINTER_TYPE + || TREE_CODE (taggr) == REFERENCE_TYPE) + && IS_AGGR_TYPE (TREE_TYPE (taggr))) + taggr = TREE_TYPE (taggr); + + /* If we know that we don't need to write out this type's + vtable, then don't write out it's dossier. Somebody + else will take care of that. */ + if (IS_AGGR_TYPE (taggr) && CLASSTYPE_VFIELD (taggr)) + { + if (CLASSTYPE_VTABLE_NEEDS_WRITING (taggr)) + { + TREE_PUBLIC (tdecl) = ! CLASSTYPE_INTERFACE_ONLY (taggr) + && CLASSTYPE_INTERFACE_KNOWN (taggr); + TREE_STATIC (tdecl) = 1; + DECL_EXTERNAL (tdecl) = 0; + } + else + { + if (write_virtuals != 0) + TREE_PUBLIC (tdecl) = 1; + } + } + else + { + DECL_EXTERNAL (tdecl) = 0; + TREE_STATIC (tdecl) = 1; + TREE_PUBLIC (tdecl) = (definition > 1); + } + } + SET_IDENTIFIER_AS_DESC (tname, build_unary_op (ADDR_EXPR, tdecl, 0)); + if (!definition || DECL_EXTERNAL (tdecl)) + { + /* That's it! */ + finish_decl (tdecl, 0, 0, 0); + return IDENTIFIER_AS_DESC (tname); + } + + /* Show that we are defining the t_desc for this type. */ + DECL_INITIAL (tdecl) = error_mark_node; + + parents = build_tree_list (NULL_TREE, integer_zero_node); + vbases = build_tree_list (NULL_TREE, integer_zero_node); + offsets = build_tree_list (NULL_TREE, integer_zero_node); + methods = NULL_TREE; + ivars = NULL_TREE; + + if (TYPE_LANG_SPECIFIC (type)) + { + int i = CLASSTYPE_N_BASECLASSES (type); + tree method_vec = CLASSTYPE_METHOD_VEC (type); + tree *meth, *end; + tree binfos = TYPE_BINFO_BASETYPES (type); + tree vb = CLASSTYPE_VBASECLASSES (type); + + while (--i >= 0) + parents = tree_cons (NULL_TREE, build_t_desc (BINFO_TYPE (TREE_VEC_ELT (binfos, i)), 0), parents); + + while (vb) + { + vbases = tree_cons (NULL_TREE, build_t_desc (BINFO_TYPE (vb), 0), vbases); + offsets = tree_cons (NULL_TREE, BINFO_OFFSET (vb), offsets); + vb = TREE_CHAIN (vb); + } + + if (method_vec) + for (meth = TREE_VEC_END (method_vec), + end = &TREE_VEC_ELT (method_vec, 0); meth-- != end; ) + if (*meth) + { + methods = tree_cons (NULL_TREE, build_m_desc (*meth), methods); + method_count++; + } + } + + if (IS_AGGR_TYPE (type)) + { + for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields)) + if (TREE_CODE (fields) == FIELD_DECL + || TREE_CODE (fields) == VAR_DECL) + { + ivars = tree_cons (NULL_TREE, build_i_desc (fields), ivars); + field_count++; + } + ivars = nreverse (ivars); + } + + parents = finish_table (0, TYPE_POINTER_TO (__t_desc_type_node), parents, 0); + vbases = finish_table (0, TYPE_POINTER_TO (__t_desc_type_node), vbases, 0); + offsets = finish_table (0, integer_type_node, offsets, 0); + if (methods == NULL_TREE) + methods = null_pointer_node; + else + methods = build_unary_op (ADDR_EXPR, + finish_table (0, __m_desc_type_node, methods, 0), + 0); + if (ivars == NULL_TREE) + ivars = null_pointer_node; + else + ivars = build_unary_op (ADDR_EXPR, + finish_table (0, __i_desc_type_node, ivars, 0), + 0); + if (TREE_TYPE (type)) + target_type = build_t_desc (TREE_TYPE (type), definition); + else + target_type = integer_zero_node; + + name_string = combine_strings (build_string (IDENTIFIER_LENGTH (tname)+1, IDENTIFIER_POINTER (tname))); + + elems = tree_cons (NULL_TREE, build_unary_op (ADDR_EXPR, name_string, 0), + tree_cons (NULL_TREE, + TYPE_SIZE(type)? size_in_bytes(type) : integer_zero_node, + /* really should use bitfield initialization here. */ + tree_cons (NULL_TREE, integer_zero_node, + tree_cons (NULL_TREE, target_type, + tree_cons (NULL_TREE, build_int_2 (field_count, 2), + tree_cons (NULL_TREE, build_int_2 (method_count, 2), + tree_cons (NULL_TREE, ivars, + tree_cons (NULL_TREE, methods, + tree_cons (NULL_TREE, build_unary_op (ADDR_EXPR, parents, 0), + tree_cons (NULL_TREE, build_unary_op (ADDR_EXPR, vbases, 0), + build_tree_list (NULL_TREE, build_unary_op (ADDR_EXPR, offsets, 0)))))))))))); + return build_generic_desc (tdecl, elems); +} + +/* Build an initializer for a __i_desc node. */ +tree +build_i_desc (decl) + tree decl; +{ + tree elems, name_string; + tree taggr; + + name_string = DECL_NAME (decl); + name_string = combine_strings (build_string (IDENTIFIER_LENGTH (name_string)+1, IDENTIFIER_POINTER (name_string))); + + /* Now decide whether this ivar should cause it's type to get + def'd or ref'd in this file. If the type we are looking at + has a proxy definition, we look at the proxy (i.e., a + `foo *' is equivalent to a `foo'). */ + taggr = TREE_TYPE (decl); + + if ((TREE_CODE (taggr) == POINTER_TYPE + || TREE_CODE (taggr) == REFERENCE_TYPE) + && TYPE_VOLATILE (taggr) == 0) + taggr = TREE_TYPE (taggr); + + elems = tree_cons (NULL_TREE, build_unary_op (ADDR_EXPR, name_string, 0), + tree_cons (NULL_TREE, DECL_FIELD_BITPOS (decl), + build_tree_list (NULL_TREE, build_t_desc (TREE_TYPE (decl), + ! IS_AGGR_TYPE (taggr))))); + taggr = build (CONSTRUCTOR, __i_desc_type_node, NULL_TREE, elems); + TREE_CONSTANT (taggr) = 1; + TREE_STATIC (taggr) = 1; + TREE_READONLY (taggr) = 1; + return taggr; +} + +/* Build an initializer for a __m_desc node. */ +tree +build_m_desc (decl) + tree decl; +{ + tree taggr, elems, name_string; + tree parm_count, req_count, vindex, vcontext; + tree parms; + int p_count, r_count; + tree parm_types = NULL_TREE; + + for (parms = TYPE_ARG_TYPES (TREE_TYPE (decl)), p_count = 0, r_count = 0; + parms != NULL_TREE; parms = TREE_CHAIN (parms), p_count++) + { + taggr = TREE_VALUE (parms); + if ((TREE_CODE (taggr) == POINTER_TYPE + || TREE_CODE (taggr) == REFERENCE_TYPE) + && TYPE_VOLATILE (taggr) == 0) + taggr = TREE_TYPE (taggr); + + parm_types = tree_cons (NULL_TREE, build_t_desc (TREE_VALUE (parms), + ! IS_AGGR_TYPE (taggr)), + parm_types); + if (TREE_PURPOSE (parms) == NULL_TREE) + r_count++; + } + + parm_types = finish_table (0, TYPE_POINTER_TO (__t_desc_type_node), + nreverse (parm_types), 0); + parm_count = build_int_2 (p_count, 0); + req_count = build_int_2 (r_count, 0); + + if (DECL_VINDEX (decl)) + vindex = DECL_VINDEX (decl); + else + vindex = integer_zero_node; + if (DECL_CONTEXT (decl) + && TREE_CODE_CLASS (TREE_CODE (DECL_CONTEXT (decl))) == 't') + vcontext = build_t_desc (DECL_CONTEXT (decl), 0); + else + vcontext = integer_zero_node; + name_string = DECL_NAME (decl); + if (name_string == NULL) + name_string = DECL_ASSEMBLER_NAME (decl); + name_string = combine_strings (build_string (IDENTIFIER_LENGTH (name_string)+1, IDENTIFIER_POINTER (name_string))); + + /* Now decide whether the return type of this mvar + should cause it's type to get def'd or ref'd in this file. + If the type we are looking at has a proxy definition, + we look at the proxy (i.e., a `foo *' is equivalent to a `foo'). */ + taggr = TREE_TYPE (TREE_TYPE (decl)); + + if ((TREE_CODE (taggr) == POINTER_TYPE + || TREE_CODE (taggr) == REFERENCE_TYPE) + && TYPE_VOLATILE (taggr) == 0) + taggr = TREE_TYPE (taggr); + + elems = tree_cons (NULL_TREE, build_unary_op (ADDR_EXPR, name_string, 0), + tree_cons (NULL_TREE, vindex, + tree_cons (NULL_TREE, vcontext, + tree_cons (NULL_TREE, build_t_desc (TREE_TYPE (TREE_TYPE (decl)), + ! IS_AGGR_TYPE (taggr)), + tree_cons (NULL_TREE, build_c_cast (TYPE_POINTER_TO (default_function_type), build_unary_op (ADDR_EXPR, decl, 0)), + tree_cons (NULL_TREE, parm_count, + tree_cons (NULL_TREE, req_count, + build_tree_list (NULL_TREE, build_unary_op (ADDR_EXPR, parm_types, 0))))))))); + + taggr = build (CONSTRUCTOR, __m_desc_type_node, NULL_TREE, elems); + TREE_CONSTANT (taggr) = 1; + TREE_STATIC (taggr) = 1; + TREE_READONLY (taggr) = 1; + return taggr; +} + +/* Conditionally emit code to set up an unwind-protect for the + garbage collector. If this function doesn't do anything that involves + the garbage collector, then do nothing. Otherwise, call __gc_push + at the beginning and __gc_pop at the end. + + NOTE! The __gc_pop function must operate transparently, since + it comes where the logical return label lies. This means that + at runtime *it* must preserve any return value registers. */ + +void +expand_gc_prologue_and_epilogue () +{ + extern tree maybe_gc_cleanup; + struct rtx_def *last_parm_insn, *mark; + extern struct rtx_def *get_last_insn (); + extern struct rtx_def *get_first_nonparm_insn (); + extern struct rtx_def *previous_insn (); + tree action; + + /* If we didn't need the obstack, don't cons any space. */ + if (current_function_obstack_index == 0 + || current_function_obstack_usage == 0) + return; + + mark = get_last_insn (); + last_parm_insn = get_first_nonparm_insn (); + if (last_parm_insn == 0) last_parm_insn = mark; + else last_parm_insn = previous_insn (last_parm_insn); + + action = build_function_call (gc_push_fndecl, + build_tree_list (NULL_TREE, size_int (++current_function_obstack_index))); + expand_expr_stmt (action); + + reorder_insns (next_insn (mark), get_last_insn (), last_parm_insn); + + /* This will be expanded as a cleanup. */ + TREE_VALUE (maybe_gc_cleanup) + = build_function_call (gc_pop_fndecl, NULL_TREE); +} + +/* Some day we'll use this function as a call-back and clean + up all the unnecessary gc dribble that we otherwise create. */ +void +lang_expand_end_bindings (first, last) + struct rtx_def *first, *last; +{ +} + +void +init_gc_processing () +{ + tree parmtypes = hash_tree_chain (class_star_type_node, + hash_tree_chain (integer_type_node, NULL_TREE)); + gc_protect_fndecl = define_function ("__gc_protect", + build_function_type (class_star_type_node, parmtypes), + NOT_BUILT_IN, 0, 0); + + parmtypes = hash_tree_chain (integer_type_node, NULL_TREE); + gc_unprotect_fndecl = define_function ("__gc_unprotect", + build_function_type (void_type_node, parmtypes), + NOT_BUILT_IN, 0, 0); + + gc_push_fndecl = define_function ("__gc_push", + TREE_TYPE (gc_unprotect_fndecl), + NOT_BUILT_IN, 0, 0); + + gc_pop_fndecl = define_function ("__gc_pop", + build_function_type (void_type_node, + void_list_node), + NOT_BUILT_IN, 0, 0); + gc_nonobject = build_int_2 (0x80000000, 0); + gc_visible = build_int_2 (0x40000000, 0); + gc_white = integer_zero_node; + gc_offwhite = build_int_2 (0x10000000, 0); + gc_grey = build_int_2 (0x20000000, 0); + gc_black = build_int_2 (0x30000000, 0); +} |
