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Diffstat (limited to 'contrib/gcc/profile.c')
| -rw-r--r-- | contrib/gcc/profile.c | 1702 |
1 files changed, 1702 insertions, 0 deletions
diff --git a/contrib/gcc/profile.c b/contrib/gcc/profile.c new file mode 100644 index 0000000..b06f91b --- /dev/null +++ b/contrib/gcc/profile.c @@ -0,0 +1,1702 @@ +/* Calculate branch probabilities, and basic block execution counts. + Copyright (C) 1990, 91-94, 96, 97, 1998 Free Software Foundation, Inc. + Contributed by James E. Wilson, UC Berkeley/Cygnus Support; + based on some ideas from Dain Samples of UC Berkeley. + Further mangling by Bob Manson, Cygnus Support. + +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. */ + +/* ??? Really should not put insns inside of LIBCALL sequences, when putting + insns after a call, should look for the insn setting the retval, and + insert the insns after that one. */ + +/* ??? Register allocation should use basic block execution counts to + give preference to the most commonly executed blocks. */ + +/* ??? The .da files are not safe. Changing the program after creating .da + files or using different options when compiling with -fbranch-probabilities + can result the arc data not matching the program. Maybe add instrumented + arc count to .bbg file? Maybe check whether PFG matches the .bbg file? */ + +/* ??? Should calculate branch probabilities before instrumenting code, since + then we can use arc counts to help decide which arcs to instrument. */ + +/* ??? Rearrange code so that the most frequently executed arcs become from + one block to the next block (i.e. a fall through), move seldom executed + code outside of loops even at the expense of adding a few branches to + achieve this, see Dain Sample's UC Berkeley thesis. */ + +#include "config.h" +#include "system.h" +#include "rtl.h" +#include "flags.h" +#include "insn-flags.h" +#include "insn-config.h" +#include "output.h" +#include "regs.h" +#include "tree.h" +#include "output.h" +#include "gcov-io.h" +#include "toplev.h" + +extern char * xmalloc (); + +/* One of these is dynamically created whenever we identify an arc in the + function. */ + +struct adj_list +{ + int source; + int target; + int arc_count; + unsigned int count_valid : 1; + unsigned int on_tree : 1; + unsigned int fake : 1; + unsigned int fall_through : 1; + rtx branch_insn; + struct adj_list *pred_next; + struct adj_list *succ_next; +}; + +#define ARC_TARGET(ARCPTR) (ARCPTR->target) +#define ARC_SOURCE(ARCPTR) (ARCPTR->source) +#define ARC_COUNT(ARCPTR) (ARCPTR->arc_count) + +/* Count the number of basic blocks, and create an array of these structures, + one for each bb in the function. */ + +struct bb_info +{ + struct adj_list *succ; + struct adj_list *pred; + int succ_count; + int pred_count; + int exec_count; + unsigned int count_valid : 1; + unsigned int on_tree : 1; + rtx first_insn; +}; + +/* Indexed by label number, gives the basic block number containing that + label. */ + +static int *label_to_bb; + +/* Number of valid entries in the label_to_bb array. */ + +static int label_to_bb_size; + +/* Indexed by block index, holds the basic block graph. */ + +static struct bb_info *bb_graph; + +/* Name and file pointer of the output file for the basic block graph. */ + +static char *bbg_file_name; +static FILE *bbg_file; + +/* Name and file pointer of the input file for the arc count data. */ + +static char *da_file_name; +static FILE *da_file; + +/* Pointer of the output file for the basic block/line number map. */ +static FILE *bb_file; + +/* Last source file name written to bb_file. */ + +static char *last_bb_file_name; + +/* Indicates whether the next line number note should be output to + bb_file or not. Used to eliminate a redundant note after an + expanded inline function call. */ + +static int ignore_next_note; + +/* Used by final, for allocating the proper amount of storage for the + instrumented arc execution counts. */ + +int count_instrumented_arcs; + +/* Number of executions for the return label. */ + +int return_label_execution_count; + +/* Collect statistics on the performance of this pass for the entire source + file. */ + +static int total_num_blocks; +static int total_num_arcs; +static int total_num_arcs_instrumented; +static int total_num_blocks_created; +static int total_num_passes; +static int total_num_times_called; +static int total_hist_br_prob[20]; +static int total_num_never_executed; +static int total_num_branches; + +/* Forward declarations. */ +static void init_arc PROTO((struct adj_list *, int, int, rtx)); +static void find_spanning_tree PROTO((int)); +static void expand_spanning_tree PROTO((int)); +static void fill_spanning_tree PROTO((int)); +static void init_arc_profiler PROTO((void)); +static void output_arc_profiler PROTO((int, rtx)); + +#ifndef LONG_TYPE_SIZE +#define LONG_TYPE_SIZE BITS_PER_WORD +#endif + +/* If non-zero, we need to output a constructor to set up the + per-object-file data. */ +static int need_func_profiler = 0; + + +/* Add arc instrumentation code to the entire insn chain. + + F is the first insn of the chain. + NUM_BLOCKS is the number of basic blocks found in F. + DUMP_FILE, if nonzero, is an rtl dump file we can write to. */ + +static void +instrument_arcs (f, num_blocks, dump_file) + rtx f; + int num_blocks; + FILE *dump_file; +{ + register int i; + register struct adj_list *arcptr, *backptr; + int num_arcs = 0; + int num_instr_arcs = 0; + rtx insn; + + /* Instrument the program start. */ + /* Handle block 0 specially, since it will always be instrumented, + but it doesn't have a valid first_insn or branch_insn. We must + put the instructions before the NOTE_INSN_FUNCTION_BEG note, so + that they don't clobber any of the parameters of the current + function. */ + for (insn = f; insn; insn = NEXT_INSN (insn)) + if (GET_CODE (insn) == NOTE + && NOTE_LINE_NUMBER (insn) == NOTE_INSN_FUNCTION_BEG) + break; + insn = PREV_INSN (insn); + need_func_profiler = 1; + output_arc_profiler (total_num_arcs_instrumented + num_instr_arcs++, insn); + + for (i = 1; i < num_blocks; i++) + for (arcptr = bb_graph[i].succ; arcptr; arcptr = arcptr->succ_next) + if (! arcptr->on_tree) + { + if (dump_file) + fprintf (dump_file, "Arc %d to %d instrumented\n", i, + ARC_TARGET (arcptr)); + + /* Check to see if this arc is the only exit from its source block, + or the only entrance to its target block. In either case, + we don't need to create a new block to instrument the arc. */ + + if (bb_graph[i].succ == arcptr && arcptr->succ_next == 0) + { + /* Instrument the source block. */ + output_arc_profiler (total_num_arcs_instrumented + + num_instr_arcs++, + PREV_INSN (bb_graph[i].first_insn)); + } + else if (arcptr == bb_graph[ARC_TARGET (arcptr)].pred + && arcptr->pred_next == 0) + { + /* Instrument the target block. */ + output_arc_profiler (total_num_arcs_instrumented + + num_instr_arcs++, + PREV_INSN (bb_graph[ARC_TARGET (arcptr)].first_insn)); + } + else if (arcptr->fall_through) + { + /* This is a fall-through; put the instrumentation code after + the branch that ends this block. */ + + for (backptr = bb_graph[i].succ; backptr; + backptr = backptr->succ_next) + if (backptr != arcptr) + break; + + output_arc_profiler (total_num_arcs_instrumented + + num_instr_arcs++, + backptr->branch_insn); + } + else + { + /* Must emit a new basic block to hold the arc counting code. */ + enum rtx_code code = GET_CODE (PATTERN (arcptr->branch_insn)); + + if (code == SET) + { + /* Create the new basic block right after the branch. + Invert the branch so that it jumps past the end of the new + block. The new block will consist of the instrumentation + code, and a jump to the target of this arc. */ + int this_is_simplejump = simplejump_p (arcptr->branch_insn); + rtx new_label = gen_label_rtx (); + rtx old_label, set_src; + rtx after = arcptr->branch_insn; + + /* Simplejumps can't reach here. */ + if (this_is_simplejump) + abort (); + + /* We can't use JUMP_LABEL, because it won't be set if we + are compiling without optimization. */ + + set_src = SET_SRC (single_set (arcptr->branch_insn)); + if (GET_CODE (set_src) == LABEL_REF) + old_label = set_src; + else if (GET_CODE (set_src) != IF_THEN_ELSE) + abort (); + else if (XEXP (set_src, 1) == pc_rtx) + old_label = XEXP (XEXP (set_src, 2), 0); + else + old_label = XEXP (XEXP (set_src, 1), 0); + + /* Set the JUMP_LABEL so that redirect_jump will work. */ + JUMP_LABEL (arcptr->branch_insn) = old_label; + + /* Add a use for OLD_LABEL that will be needed when we emit + the JUMP_INSN below. If we don't do this here, + `invert_jump' might delete it for us. We must add two + when not optimizing, because the NUSES is zero now, + but must be at least two to prevent the label from being + deleted. */ + LABEL_NUSES (old_label) += 2; + + /* Emit the insns for the new block in reverse order, + since that is most convenient. */ + + if (this_is_simplejump) + { + after = NEXT_INSN (arcptr->branch_insn); + if (! redirect_jump (arcptr->branch_insn, new_label)) + /* Don't know what to do if this branch won't + redirect. */ + abort (); + } + else + { + if (! invert_jump (arcptr->branch_insn, new_label)) + /* Don't know what to do if this branch won't invert. */ + abort (); + + emit_label_after (new_label, after); + LABEL_NUSES (new_label)++; + } + emit_barrier_after (after); + emit_jump_insn_after (gen_jump (old_label), after); + JUMP_LABEL (NEXT_INSN (after)) = old_label; + + /* Instrument the source arc. */ + output_arc_profiler (total_num_arcs_instrumented + + num_instr_arcs++, + after); + if (this_is_simplejump) + { + emit_label_after (new_label, after); + LABEL_NUSES (new_label)++; + } + } + else if (code == ADDR_VEC || code == ADDR_DIFF_VEC) + { + /* A table jump. Create a new basic block immediately + after the table, by emitting a barrier, a label, a + counting note, and a jump to the old label. Put the + new label in the table. */ + + rtx new_label = gen_label_rtx (); + rtx old_lref, new_lref; + int index; + + /* Must determine the old_label reference, do this + by counting the arcs after this one, which will + give the index of our label in the table. */ + + index = 0; + for (backptr = arcptr->succ_next; backptr; + backptr = backptr->succ_next) + index++; + + old_lref = XVECEXP (PATTERN (arcptr->branch_insn), + (code == ADDR_DIFF_VEC), index); + + /* Emit the insns for the new block in reverse order, + since that is most convenient. */ + emit_jump_insn_after (gen_jump (XEXP (old_lref, 0)), + arcptr->branch_insn); + JUMP_LABEL (NEXT_INSN (arcptr->branch_insn)) + = XEXP (old_lref, 0); + + /* Instrument the source arc. */ + output_arc_profiler (total_num_arcs_instrumented + + num_instr_arcs++, + arcptr->branch_insn); + + emit_label_after (new_label, arcptr->branch_insn); + LABEL_NUSES (NEXT_INSN (arcptr->branch_insn))++; + emit_barrier_after (arcptr->branch_insn); + + /* Fix up the table jump. */ + new_lref = gen_rtx_LABEL_REF (Pmode, new_label); + XVECEXP (PATTERN (arcptr->branch_insn), + (code == ADDR_DIFF_VEC), index) = new_lref; + } + else + abort (); + + num_arcs += 1; + if (dump_file) + fprintf (dump_file, + "Arc %d to %d needed new basic block\n", i, + ARC_TARGET (arcptr)); + } + } + + total_num_arcs_instrumented += num_instr_arcs; + count_instrumented_arcs = total_num_arcs_instrumented; + + total_num_blocks_created += num_arcs; + if (dump_file) + { + fprintf (dump_file, "%d arcs instrumented\n", num_instr_arcs); + fprintf (dump_file, "%d extra basic blocks created\n", num_arcs); + } +} + +/* Output STRING to bb_file, surrounded by DELIMITER. */ + +static void +output_gcov_string (string, delimiter) + char *string; + long delimiter; +{ + long temp; + + /* Write a delimiter to indicate that a file name follows. */ + __write_long (delimiter, bb_file, 4); + + /* Write the string. */ + temp = strlen (string) + 1; + fwrite (string, temp, 1, bb_file); + + /* Append a few zeros, to align the output to a 4 byte boundary. */ + temp = temp & 0x3; + if (temp) + { + char c[4]; + + c[0] = c[1] = c[2] = c[3] = 0; + fwrite (c, sizeof (char), 4 - temp, bb_file); + } + + /* Store another delimiter in the .bb file, just to make it easy to find the + end of the file name. */ + __write_long (delimiter, bb_file, 4); +} + +/* Return TRUE if this insn must be a tablejump entry insn. This works for + the MIPS port, but may give false negatives for some targets. */ + +int +tablejump_entry_p (insn, label) + rtx insn, label; +{ + rtx next = next_active_insn (insn); + enum rtx_code code = GET_CODE (PATTERN (next)); + + if (code != ADDR_DIFF_VEC && code != ADDR_VEC) + return 0; + + if (PREV_INSN (next) == XEXP (label, 0)) + return 1; + + return 0; +} + +/* Instrument and/or analyze program behavior based on program flow graph. + In either case, this function builds a flow graph for the function being + compiled. The flow graph is stored in BB_GRAPH. + + When FLAG_PROFILE_ARCS is nonzero, this function instruments the arcs in + the flow graph that are needed to reconstruct the dynamic behavior of the + flow graph. + + When FLAG_BRANCH_PROBABILITIES is nonzero, this function reads auxiliary + information from a data file containing arc count information from previous + executions of the function being compiled. In this case, the flow graph is + annotated with actual execution counts, which are later propagated into the + rtl for optimization purposes. + + Main entry point of this file. */ + +void +branch_prob (f, dump_file) + rtx f; + FILE *dump_file; +{ + int i, num_blocks; + struct adj_list *arcptr; + int num_arcs, changes, passes; + int total, prob; + int hist_br_prob[20], num_never_executed, num_branches; + /* Set to non-zero if we got bad count information. */ + int bad_counts = 0; + + /* start of a function. */ + if (flag_test_coverage) + output_gcov_string (current_function_name, (long) -2); + + /* Execute this only if doing arc profiling or branch probabilities. */ + if (! profile_arc_flag && ! flag_branch_probabilities + && ! flag_test_coverage) + abort (); + + total_num_times_called++; + + /* Create an array label_to_bb of ints of size max_label_num. */ + label_to_bb_size = max_label_num (); + label_to_bb = (int *) oballoc (label_to_bb_size * sizeof (int)); + bzero ((char *) label_to_bb, label_to_bb_size * sizeof (int)); + + /* Scan the insns in the function, count the number of basic blocks + present. When a code label is passed, set label_to_bb[label] = bb + number. */ + + /* The first block found will be block 1, so that function entry can be + block 0. */ + + { + register RTX_CODE prev_code = JUMP_INSN; + register RTX_CODE code; + register rtx insn; + register int i; + int block_separator_emitted = 0; + + ignore_next_note = 0; + + for (insn = NEXT_INSN (f), i = 0; insn; insn = NEXT_INSN (insn)) + { + code = GET_CODE (insn); + + if (code == BARRIER) + ; + else if (code == CODE_LABEL) + /* This label is part of the next block, but we can't increment + block number yet since there might be multiple labels. */ + label_to_bb[CODE_LABEL_NUMBER (insn)] = i + 1; + /* We make NOTE_INSN_SETJMP notes into a block of their own, so that + they can be the target of the fake arc for the setjmp call. + This avoids creating cycles of fake arcs, which would happen if + the block after the setjmp call contained a call insn. */ + else if ((prev_code == JUMP_INSN || prev_code == CALL_INSN + || prev_code == CODE_LABEL || prev_code == BARRIER) + && (GET_RTX_CLASS (code) == 'i' + || (code == NOTE + && NOTE_LINE_NUMBER (insn) == NOTE_INSN_SETJMP))) + { + i += 1; + + /* Emit the block separator if it hasn't already been emitted. */ + if (flag_test_coverage && ! block_separator_emitted) + { + /* Output a zero to the .bb file to indicate that a new + block list is starting. */ + __write_long (0, bb_file, 4); + } + block_separator_emitted = 0; + } + /* If flag_test_coverage is true, then we must add an entry to the + .bb file for every note. */ + else if (code == NOTE && flag_test_coverage) + { + /* Must ignore the line number notes that immediately follow the + end of an inline function to avoid counting it twice. There + is a note before the call, and one after the call. */ + if (NOTE_LINE_NUMBER (insn) == NOTE_REPEATED_LINE_NUMBER) + ignore_next_note = 1; + else if (NOTE_LINE_NUMBER (insn) > 0) + { + if (ignore_next_note) + ignore_next_note = 0; + else + { + /* Emit a block separator here to ensure that a NOTE + immediately following a JUMP_INSN or CALL_INSN will end + up in the right basic block list. */ + if ((prev_code == JUMP_INSN || prev_code == CALL_INSN + || prev_code == CODE_LABEL || prev_code == BARRIER) + && ! block_separator_emitted) + { + /* Output a zero to the .bb file to indicate that + a new block list is starting. */ + __write_long (0, bb_file, 4); + + block_separator_emitted = 1; + } + + /* If this is a new source file, then output the file's + name to the .bb file. */ + if (! last_bb_file_name + || strcmp (NOTE_SOURCE_FILE (insn), + last_bb_file_name)) + { + if (last_bb_file_name) + free (last_bb_file_name); + last_bb_file_name + = xmalloc (strlen (NOTE_SOURCE_FILE (insn)) + 1); + strcpy (last_bb_file_name, NOTE_SOURCE_FILE (insn)); + output_gcov_string (NOTE_SOURCE_FILE (insn), (long)-1); + } + + /* Output the line number to the .bb file. Must be done + after the output_bb_profile_data() call, and after the + file name is written, to ensure that it is correctly + handled by gcov. */ + __write_long (NOTE_LINE_NUMBER (insn), bb_file, 4); + } + } + } + + if (code != NOTE) + prev_code = code; + else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_SETJMP) + prev_code = CALL_INSN; + } + + /* Allocate last `normal' entry for bb_graph. */ + + /* The last insn was a jump, call, or label. In that case we have + a block at the end of the function with no insns. */ + if (prev_code == JUMP_INSN || prev_code == CALL_INSN + || prev_code == CODE_LABEL || prev_code == BARRIER) + { + i++; + + /* Emit the block separator if it hasn't already been emitted. */ + if (flag_test_coverage && ! block_separator_emitted) + { + /* Output a zero to the .bb file to indicate that a new + block list is starting. */ + __write_long (0, bb_file, 4); + } + } + + /* Create another block to stand for EXIT, and make all return insns, and + the last basic block point here. Add one more to account for block + zero. */ + num_blocks = i + 2; + } + + total_num_blocks += num_blocks; + if (dump_file) + fprintf (dump_file, "%d basic blocks\n", num_blocks); + + /* If we are only doing test coverage here, then return now. */ + if (! profile_arc_flag && ! flag_branch_probabilities) + return; + + /* Create and initialize the arrays that will hold bb_graph + and execution count info. */ + + bb_graph = (struct bb_info *) alloca (num_blocks * sizeof (struct bb_info)); + bzero ((char *) bb_graph, (sizeof (struct bb_info) * num_blocks)); + + { + /* Scan the insns again: + - at the entry to each basic block, increment the predecessor count + (and successor of previous block) if it is a fall through entry, + create adj_list entries for this and the previous block + - at each jump insn, increment predecessor/successor counts for + target/source basic blocks, add this insn to pred/succ lists. + + This also cannot be broken out as a separate subroutine + because it uses `alloca'. */ + + register RTX_CODE prev_code = JUMP_INSN; + register RTX_CODE code; + register rtx insn; + register int i; + int fall_through = 0; + struct adj_list *arcptr; + int dest = 0; + + /* Block 0 always falls through to block 1. */ + num_arcs = 0; + arcptr = (struct adj_list *) alloca (sizeof (struct adj_list)); + init_arc (arcptr, 0, 1, 0); + arcptr->fall_through = 1; + num_arcs++; + + /* Add a fake fall through arc from the last block to block 0, to make the + graph complete. */ + arcptr = (struct adj_list *) alloca (sizeof (struct adj_list)); + init_arc (arcptr, num_blocks - 1, 0, 0); + arcptr->fake = 1; + num_arcs++; + + /* Exit must be one node of the graph, and all exits from the function + must point there. When see a return branch, must point the arc to the + exit node. */ + + /* Must start scan with second insn in function as above. */ + for (insn = NEXT_INSN (f), i = 0; insn; insn = NEXT_INSN (insn)) + { + code = GET_CODE (insn); + + if (code == BARRIER) + fall_through = 0; + else if (code == CODE_LABEL) + ; + /* We make NOTE_INSN_SETJMP notes into a block of their own, so that + they can be the target of the fake arc for the setjmp call. + This avoids creating cycles of fake arcs, which would happen if + the block after the setjmp call ended with a call. */ + else if ((prev_code == JUMP_INSN || prev_code == CALL_INSN + || prev_code == CODE_LABEL || prev_code == BARRIER) + && (GET_RTX_CLASS (code) == 'i' + || (code == NOTE + && NOTE_LINE_NUMBER (insn) == NOTE_INSN_SETJMP))) + { + /* This is the first insn of the block. */ + i += 1; + if (fall_through) + { + arcptr = (struct adj_list *) alloca (sizeof (struct adj_list)); + init_arc (arcptr, i - 1, i, 0); + arcptr->fall_through = 1; + + num_arcs++; + } + fall_through = 1; + bb_graph[i].first_insn = insn; + } + else if (code == NOTE) + {;} + + if (code == CALL_INSN) + { + /* In the normal case, the call returns, and this is just like + a branch fall through. */ + fall_through = 1; + + /* Setjmp may return more times than called, so to make the graph + solvable, add a fake arc from the function entrance to the + next block. + + All other functions may return fewer times than called (if + a descendent call longjmp or exit), so to make the graph + solvable, add a fake arc to the function exit from the + current block. + + Distinguish the cases by checking for a SETJUMP note. + A call_insn can be the last ins of a function, so must check + to see if next insn actually exists. */ + arcptr = (struct adj_list *) alloca (sizeof (struct adj_list)); + if (NEXT_INSN (insn) + && GET_CODE (NEXT_INSN (insn)) == NOTE + && NOTE_LINE_NUMBER (NEXT_INSN (insn)) == NOTE_INSN_SETJMP) + init_arc (arcptr, 0, i+1, insn); + else + init_arc (arcptr, i, num_blocks-1, insn); + arcptr->fake = 1; + num_arcs++; + } + else if (code == JUMP_INSN) + { + rtx tem, pattern = PATTERN (insn); + rtx tablejump = 0; + + /* If running without optimization, then jump label won't be valid, + so we must search for the destination label in that case. + We have to handle tablejumps and returns specially anyways, so + we don't check the JUMP_LABEL at all here. */ + + /* ??? This code should be rewritten. We need a more elegant way + to find the LABEL_REF. We need a more elegant way to + differentiate tablejump entries from computed gotos. + We should perhaps reuse code from flow to compute the CFG + instead of trying to compute it here. + + We can't use current_function_has_computed_jump, because that + is calculated later by flow. We can't use computed_jump_p, + because that returns true for tablejump entry insns for some + targets, e.g. HPPA and MIPS. */ + + if (GET_CODE (pattern) == PARALLEL) + { + /* This assumes that PARALLEL jumps with a USE are + tablejump entry jumps. The same assumption can be found + in computed_jump_p. */ + /* Make an arc from this jump to the label of the + jump table. This will instrument the number of + times the switch statement is executed. */ + if (GET_CODE (XVECEXP (pattern, 0, 1)) == USE) + { + tem = XEXP (XVECEXP (pattern, 0, 1), 0); + if (GET_CODE (tem) != LABEL_REF) + abort (); + dest = label_to_bb[CODE_LABEL_NUMBER (XEXP (tem, 0))]; + } + else if (GET_CODE (XVECEXP (pattern, 0, 0)) == SET + && SET_DEST (XVECEXP (pattern, 0, 0)) == pc_rtx) + { + tem = SET_SRC (XVECEXP (pattern, 0, 0)); + if (GET_CODE (tem) == PLUS + && GET_CODE (XEXP (tem, 1)) == LABEL_REF) + { + tem = XEXP (tem, 1); + dest = label_to_bb [CODE_LABEL_NUMBER (XEXP (tem, 0))]; + } + } + else + abort (); + } + else if (GET_CODE (pattern) == ADDR_VEC + || GET_CODE (pattern) == ADDR_DIFF_VEC) + tablejump = pattern; + else if (GET_CODE (pattern) == RETURN) + dest = num_blocks - 1; + else if (GET_CODE (pattern) != SET) + abort (); + else if ((tem = SET_SRC (pattern)) + && GET_CODE (tem) == LABEL_REF) + dest = label_to_bb[CODE_LABEL_NUMBER (XEXP (tem, 0))]; + /* Recognize HPPA table jump entry. This code is similar to + the code above in the PARALLEL case. */ + else if (GET_CODE (tem) == PLUS + && GET_CODE (XEXP (tem, 0)) == MEM + && GET_CODE (XEXP (XEXP (tem, 0), 0)) == PLUS + && GET_CODE (XEXP (XEXP (XEXP (tem, 0), 0), 0)) == PC + && GET_CODE (XEXP (tem, 1)) == LABEL_REF + && tablejump_entry_p (insn, XEXP (tem, 1))) + dest = label_to_bb[CODE_LABEL_NUMBER (XEXP (XEXP (tem, 1), 0))]; + /* Recognize the MIPS table jump entry. */ + else if (GET_CODE (tem) == PLUS + && GET_CODE (XEXP (tem, 0)) == REG + && GET_CODE (XEXP (tem, 1)) == LABEL_REF + && tablejump_entry_p (insn, XEXP (tem, 1))) + dest = label_to_bb[CODE_LABEL_NUMBER (XEXP (XEXP (tem, 1), 0))]; + else + { + rtx label_ref; + + /* Must be an IF_THEN_ELSE branch. If it isn't, assume it + is a computed goto, which aren't supported yet. */ + if (GET_CODE (tem) != IF_THEN_ELSE) + fatal ("-fprofile-arcs does not support computed gotos"); + if (XEXP (tem, 1) != pc_rtx) + label_ref = XEXP (tem, 1); + else + label_ref = XEXP (tem, 2); + dest = label_to_bb[CODE_LABEL_NUMBER (XEXP (label_ref, 0))]; + } + + if (tablejump) + { + int diff_vec_p = GET_CODE (tablejump) == ADDR_DIFF_VEC; + int len = XVECLEN (tablejump, diff_vec_p); + int k; + + for (k = 0; k < len; k++) + { + rtx tem = XEXP (XVECEXP (tablejump, diff_vec_p, k), 0); + dest = label_to_bb[CODE_LABEL_NUMBER (tem)]; + + arcptr = (struct adj_list *) alloca (sizeof(struct adj_list)); + init_arc (arcptr, i, dest, insn); + + num_arcs++; + } + } + else + { + arcptr = (struct adj_list *) alloca (sizeof (struct adj_list)); + init_arc (arcptr, i, dest, insn); + + num_arcs++; + } + + /* Determine whether or not this jump will fall through. + Unconditional jumps and returns are not always followed by + barriers. */ + pattern = PATTERN (insn); + if (GET_CODE (pattern) == PARALLEL + || GET_CODE (pattern) == RETURN) + fall_through = 0; + else if (GET_CODE (pattern) == ADDR_VEC + || GET_CODE (pattern) == ADDR_DIFF_VEC) + /* These aren't actually jump insns, but they never fall + through, so... */ + fall_through = 0; + else + { + if (GET_CODE (pattern) != SET || SET_DEST (pattern) != pc_rtx) + abort (); + if (GET_CODE (SET_SRC (pattern)) != IF_THEN_ELSE) + fall_through = 0; + } + } + + if (code != NOTE) + prev_code = code; + else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_SETJMP) + { + /* Make a fake insn to tag our notes on. */ + bb_graph[i].first_insn = insn + = emit_insn_after (gen_rtx_USE (VOIDmode, stack_pointer_rtx), + insn); + prev_code = CALL_INSN; + } + } + + /* If the code at the end of the function would give a new block, then + do the following. */ + + if (prev_code == JUMP_INSN || prev_code == CALL_INSN + || prev_code == CODE_LABEL || prev_code == BARRIER) + { + if (fall_through) + { + arcptr = (struct adj_list *) alloca (sizeof (struct adj_list)); + init_arc (arcptr, i, i + 1, 0); + arcptr->fall_through = 1; + + num_arcs++; + } + + /* This may not be a real insn, but that should not cause a problem. */ + bb_graph[i+1].first_insn = get_last_insn (); + } + + /* There is always a fake arc from the last block of the function + to the function exit block. */ + arcptr = (struct adj_list *) alloca (sizeof (struct adj_list)); + init_arc (arcptr, num_blocks-2, num_blocks-1, 0); + arcptr->fake = 1; + num_arcs++; + } + + total_num_arcs += num_arcs; + if (dump_file) + fprintf (dump_file, "%d arcs\n", num_arcs); + + /* Create spanning tree from basic block graph, mark each arc that is + on the spanning tree. */ + + /* To reduce the instrumentation cost, make two passes over the tree. + First, put as many must-split (crowded and fake) arcs on the tree as + possible, then on the second pass fill in the rest of the tree. + Note that the spanning tree is considered undirected, so that as many + must-split arcs as possible can be put on it. + + Fallthrough arcs which are crowded should not be chosen on the first + pass, since they do not require creating a new basic block. These + arcs will have fall_through set. */ + + find_spanning_tree (num_blocks); + + /* Create a .bbg file from which gcov can reconstruct the basic block + graph. First output the number of basic blocks, and then for every + arc output the source and target basic block numbers. + NOTE: The format of this file must be compatible with gcov. */ + + if (flag_test_coverage) + { + int flag_bits; + + __write_long (num_blocks, bbg_file, 4); + __write_long (num_arcs, bbg_file, 4); + + for (i = 0; i < num_blocks; i++) + { + long count = 0; + for (arcptr = bb_graph[i].succ; arcptr; arcptr = arcptr->succ_next) + count++; + __write_long (count, bbg_file, 4); + + for (arcptr = bb_graph[i].succ; arcptr; arcptr = arcptr->succ_next) + { + flag_bits = 0; + if (arcptr->on_tree) + flag_bits |= 0x1; + if (arcptr->fake) + flag_bits |= 0x2; + if (arcptr->fall_through) + flag_bits |= 0x4; + + __write_long (ARC_TARGET (arcptr), bbg_file, 4); + __write_long (flag_bits, bbg_file, 4); + } + } + + /* Emit a -1 to separate the list of all arcs from the list of + loop back edges that follows. */ + __write_long (-1, bbg_file, 4); + } + + /* For each arc not on the spanning tree, add counting code as rtl. */ + + if (profile_arc_flag) + { + instrument_arcs (f, num_blocks, dump_file); + allocate_reg_info (max_reg_num (), FALSE, FALSE); + } + + /* Execute the rest only if doing branch probabilities. */ + if (! flag_branch_probabilities) + return; + + /* For each arc not on the spanning tree, set its execution count from + the .da file. */ + + /* The first count in the .da file is the number of times that the function + was entered. This is the exec_count for block zero. */ + + num_arcs = 0; + for (i = 0; i < num_blocks; i++) + for (arcptr = bb_graph[i].succ; arcptr; arcptr = arcptr->succ_next) + if (! arcptr->on_tree) + { + num_arcs++; + if (da_file) + { + long value; + __read_long (&value, da_file, 8); + ARC_COUNT (arcptr) = value; + } + else + ARC_COUNT (arcptr) = 0; + arcptr->count_valid = 1; + bb_graph[i].succ_count--; + bb_graph[ARC_TARGET (arcptr)].pred_count--; + } + + if (dump_file) + fprintf (dump_file, "%d arc counts read\n", num_arcs); + + /* For every block in the file, + - if every exit/entrance arc has a known count, then set the block count + - if the block count is known, and every exit/entrance arc but one has + a known execution count, then set the count of the remaining arc + + As arc counts are set, decrement the succ/pred count, but don't delete + the arc, that way we can easily tell when all arcs are known, or only + one arc is unknown. */ + + /* The order that the basic blocks are iterated through is important. + Since the code that finds spanning trees starts with block 0, low numbered + arcs are put on the spanning tree in preference to high numbered arcs. + Hence, most instrumented arcs are at the end. Graph solving works much + faster if we propagate numbers from the end to the start. + + This takes an average of slightly more than 3 passes. */ + + changes = 1; + passes = 0; + while (changes) + { + passes++; + changes = 0; + + for (i = num_blocks - 1; i >= 0; i--) + { + struct bb_info *binfo = &bb_graph[i]; + if (! binfo->count_valid) + { + if (binfo->succ_count == 0) + { + total = 0; + for (arcptr = binfo->succ; arcptr; + arcptr = arcptr->succ_next) + total += ARC_COUNT (arcptr); + binfo->exec_count = total; + binfo->count_valid = 1; + changes = 1; + } + else if (binfo->pred_count == 0) + { + total = 0; + for (arcptr = binfo->pred; arcptr; + arcptr = arcptr->pred_next) + total += ARC_COUNT (arcptr); + binfo->exec_count = total; + binfo->count_valid = 1; + changes = 1; + } + } + if (binfo->count_valid) + { + if (binfo->succ_count == 1) + { + total = 0; + /* One of the counts will be invalid, but it is zero, + so adding it in also doesn't hurt. */ + for (arcptr = binfo->succ; arcptr; + arcptr = arcptr->succ_next) + total += ARC_COUNT (arcptr); + /* Calculate count for remaining arc by conservation. */ + total = binfo->exec_count - total; + /* Search for the invalid arc, and set its count. */ + for (arcptr = binfo->succ; arcptr; + arcptr = arcptr->succ_next) + if (! arcptr->count_valid) + break; + if (! arcptr) + abort (); + arcptr->count_valid = 1; + ARC_COUNT (arcptr) = total; + binfo->succ_count--; + + bb_graph[ARC_TARGET (arcptr)].pred_count--; + changes = 1; + } + if (binfo->pred_count == 1) + { + total = 0; + /* One of the counts will be invalid, but it is zero, + so adding it in also doesn't hurt. */ + for (arcptr = binfo->pred; arcptr; + arcptr = arcptr->pred_next) + total += ARC_COUNT (arcptr); + /* Calculate count for remaining arc by conservation. */ + total = binfo->exec_count - total; + /* Search for the invalid arc, and set its count. */ + for (arcptr = binfo->pred; arcptr; + arcptr = arcptr->pred_next) + if (! arcptr->count_valid) + break; + if (! arcptr) + abort (); + arcptr->count_valid = 1; + ARC_COUNT (arcptr) = total; + binfo->pred_count--; + + bb_graph[ARC_SOURCE (arcptr)].succ_count--; + changes = 1; + } + } + } + } + + total_num_passes += passes; + if (dump_file) + fprintf (dump_file, "Graph solving took %d passes.\n\n", passes); + + /* If the graph has been correctly solved, every block will have a + succ and pred count of zero. */ + for (i = 0; i < num_blocks; i++) + { + struct bb_info *binfo = &bb_graph[i]; + if (binfo->succ_count || binfo->pred_count) + abort (); + } + + /* For every arc, calculate its branch probability and add a reg_note + to the branch insn to indicate this. */ + + for (i = 0; i < 20; i++) + hist_br_prob[i] = 0; + num_never_executed = 0; + num_branches = 0; + + for (i = 0; i < num_blocks; i++) + { + struct bb_info *binfo = &bb_graph[i]; + + total = binfo->exec_count; + for (arcptr = binfo->succ; arcptr; arcptr = arcptr->succ_next) + { + if (arcptr->branch_insn) + { + /* This calculates the branch probability as an integer between + 0 and REG_BR_PROB_BASE, properly rounded to the nearest + integer. Perform the arithmetic in double to avoid + overflowing the range of ints. */ + + if (total == 0) + prob = -1; + else + { + rtx pat = PATTERN (arcptr->branch_insn); + + prob = (((double)ARC_COUNT (arcptr) * REG_BR_PROB_BASE) + + (total >> 1)) / total; + if (prob < 0 || prob > REG_BR_PROB_BASE) + { + if (dump_file) + fprintf (dump_file, "bad count: prob for %d-%d thought to be %d (forcibly normalized)\n", + ARC_SOURCE (arcptr), ARC_TARGET (arcptr), + prob); + + bad_counts = 1; + prob = REG_BR_PROB_BASE / 2; + } + + /* Match up probability with JUMP pattern. */ + + if (GET_CODE (pat) == SET + && GET_CODE (SET_SRC (pat)) == IF_THEN_ELSE) + { + if (ARC_TARGET (arcptr) == ARC_SOURCE (arcptr) + 1) + { + /* A fall through arc should never have a + branch insn. */ + abort (); + } + else + { + /* This is the arc for the taken branch. */ + if (GET_CODE (XEXP (SET_SRC (pat), 2)) != PC) + prob = REG_BR_PROB_BASE - prob; + } + } + } + + if (prob == -1) + num_never_executed++; + else + { + int index = prob * 20 / REG_BR_PROB_BASE; + if (index == 20) + index = 19; + hist_br_prob[index]++; + } + num_branches++; + + REG_NOTES (arcptr->branch_insn) + = gen_rtx_EXPR_LIST (REG_BR_PROB, GEN_INT (prob), + REG_NOTES (arcptr->branch_insn)); + } + } + + /* Add a REG_EXEC_COUNT note to the first instruction of this block. */ + if (! binfo->first_insn + || GET_RTX_CLASS (GET_CODE (binfo->first_insn)) != 'i') + { + /* Block 0 is a fake block representing function entry, and does + not have a real first insn. The second last block might not + begin with a real insn. */ + if (i == num_blocks - 1) + return_label_execution_count = total; + else if (i != 0 && i != num_blocks - 2) + abort (); + } + else + { + REG_NOTES (binfo->first_insn) + = gen_rtx_EXPR_LIST (REG_EXEC_COUNT, GEN_INT (total), + REG_NOTES (binfo->first_insn)); + if (i == num_blocks - 1) + return_label_execution_count = total; + } + } + + /* This should never happen. */ + if (bad_counts) + warning ("Arc profiling: some arc counts were bad."); + + if (dump_file) + { + fprintf (dump_file, "%d branches\n", num_branches); + fprintf (dump_file, "%d branches never executed\n", + num_never_executed); + if (num_branches) + for (i = 0; i < 10; i++) + fprintf (dump_file, "%d%% branches in range %d-%d%%\n", + (hist_br_prob[i]+hist_br_prob[19-i])*100/num_branches, + 5*i, 5*i+5); + + total_num_branches += num_branches; + total_num_never_executed += num_never_executed; + for (i = 0; i < 20; i++) + total_hist_br_prob[i] += hist_br_prob[i]; + } + +} + +/* Initialize a new arc. + ARCPTR is the empty adj_list this function fills in. + SOURCE is the block number of the source block. + TARGET is the block number of the target block. + INSN is the insn which transfers control from SOURCE to TARGET, + or zero if the transfer is implicit. */ + +static void +init_arc (arcptr, source, target, insn) + struct adj_list *arcptr; + int source, target; + rtx insn; +{ + ARC_TARGET (arcptr) = target; + ARC_SOURCE (arcptr) = source; + + ARC_COUNT (arcptr) = 0; + arcptr->count_valid = 0; + arcptr->on_tree = 0; + arcptr->fake = 0; + arcptr->fall_through = 0; + arcptr->branch_insn = insn; + + arcptr->succ_next = bb_graph[source].succ; + bb_graph[source].succ = arcptr; + bb_graph[source].succ_count++; + + arcptr->pred_next = bb_graph[target].pred; + bb_graph[target].pred = arcptr; + bb_graph[target].pred_count++; +} + +/* This function searches all of the arcs in the program flow graph, and puts + as many bad arcs as possible onto the spanning tree. Bad arcs include + fake arcs (needed for setjmp(), longjmp(), exit()) which MUST be on the + spanning tree as they can't be instrumented. Also, arcs which must be + split when instrumented should be part of the spanning tree if possible. */ + +static void +find_spanning_tree (num_blocks) + int num_blocks; +{ + int i; + struct adj_list *arcptr; + struct bb_info *binfo = &bb_graph[0]; + + /* Fake arcs must be part of the spanning tree, and are always safe to put + on the spanning tree. Fake arcs will either be a successor of node 0, + a predecessor of the last node, or from the last node to node 0. */ + + for (arcptr = bb_graph[0].succ; arcptr; arcptr = arcptr->succ_next) + if (arcptr->fake) + { + /* Adding this arc should never cause a cycle. This is a fatal + error if it would. */ + if (bb_graph[ARC_TARGET (arcptr)].on_tree && binfo->on_tree) + abort(); + else + { + arcptr->on_tree = 1; + bb_graph[ARC_TARGET (arcptr)].on_tree = 1; + binfo->on_tree = 1; + } + } + + binfo = &bb_graph[num_blocks-1]; + for (arcptr = binfo->pred; arcptr; arcptr = arcptr->pred_next) + if (arcptr->fake) + { + /* Adding this arc should never cause a cycle. This is a fatal + error if it would. */ + if (bb_graph[ARC_SOURCE (arcptr)].on_tree && binfo->on_tree) + abort(); + else + { + arcptr->on_tree = 1; + bb_graph[ARC_SOURCE (arcptr)].on_tree = 1; + binfo->on_tree = 1; + } + } + /* The only entrace to node zero is a fake arc. */ + bb_graph[0].pred->on_tree = 1; + + /* Arcs which are crowded at both the source and target should be put on + the spanning tree if possible, except for fall_throuch arcs which never + require adding a new block even if crowded, add arcs with the same source + and dest which must always be instrumented. */ + for (i = 0; i < num_blocks; i++) + { + binfo = &bb_graph[i]; + + for (arcptr = binfo->succ; arcptr; arcptr = arcptr->succ_next) + if (! ((binfo->succ == arcptr && arcptr->succ_next == 0) + || (bb_graph[ARC_TARGET (arcptr)].pred + && arcptr->pred_next == 0)) + && ! arcptr->fall_through + && ARC_TARGET (arcptr) != i) + { + /* This is a crowded arc at both source and target. Try to put + in on the spanning tree. Can do this if either the source or + target block is not yet on the tree. */ + if (! bb_graph[ARC_TARGET (arcptr)].on_tree || ! binfo->on_tree) + { + arcptr->on_tree = 1; + bb_graph[ARC_TARGET (arcptr)].on_tree = 1; + binfo->on_tree = 1; + } + } + } + + /* Clear all of the basic block on_tree bits, so that we can use them to + create the spanning tree. */ + for (i = 0; i < num_blocks; i++) + bb_graph[i].on_tree = 0; + + /* Now fill in the spanning tree until every basic block is on it. + Don't put the 0 to 1 fall through arc on the tree, since it is + always cheap to instrument, so start filling the tree from node 1. */ + + for (i = 1; i < num_blocks; i++) + for (arcptr = bb_graph[i].succ; arcptr; arcptr = arcptr->succ_next) + if (! arcptr->on_tree + && ! bb_graph[ARC_TARGET (arcptr)].on_tree) + { + fill_spanning_tree (i); + break; + } +} + +/* Add arcs reached from BLOCK to the spanning tree if they are needed and + not already there. */ + +static void +fill_spanning_tree (block) + int block; +{ + struct adj_list *arcptr; + + expand_spanning_tree (block); + + for (arcptr = bb_graph[block].succ; arcptr; arcptr = arcptr->succ_next) + if (! arcptr->on_tree + && ! bb_graph[ARC_TARGET (arcptr)].on_tree) + { + arcptr->on_tree = 1; + fill_spanning_tree (ARC_TARGET (arcptr)); + } +} + +/* When first visit a block, must add all blocks that are already connected + to this block via tree arcs to the spanning tree. */ + +static void +expand_spanning_tree (block) + int block; +{ + struct adj_list *arcptr; + + bb_graph[block].on_tree = 1; + + for (arcptr = bb_graph[block].succ; arcptr; arcptr = arcptr->succ_next) + if (arcptr->on_tree && ! bb_graph[ARC_TARGET (arcptr)].on_tree) + expand_spanning_tree (ARC_TARGET (arcptr)); + + for (arcptr = bb_graph[block].pred; + arcptr; arcptr = arcptr->pred_next) + if (arcptr->on_tree && ! bb_graph[ARC_SOURCE (arcptr)].on_tree) + expand_spanning_tree (ARC_SOURCE (arcptr)); +} + +/* Perform file-level initialization for branch-prob processing. */ + +void +init_branch_prob (filename) + char *filename; +{ + long len; + int i; + + if (flag_test_coverage) + { + /* Open an output file for the basic block/line number map. */ + int len = strlen (filename); + char *data_file = (char *) alloca (len + 4); + strcpy (data_file, filename); + strip_off_ending (data_file, len); + strcat (data_file, ".bb"); + if ((bb_file = fopen (data_file, "w")) == 0) + pfatal_with_name (data_file); + + /* Open an output file for the program flow graph. */ + len = strlen (filename); + bbg_file_name = (char *) alloca (len + 5); + strcpy (bbg_file_name, filename); + strip_off_ending (bbg_file_name, len); + strcat (bbg_file_name, ".bbg"); + if ((bbg_file = fopen (bbg_file_name, "w")) == 0) + pfatal_with_name (bbg_file_name); + + /* Initialize to zero, to ensure that the first file name will be + written to the .bb file. */ + last_bb_file_name = 0; + } + + if (flag_branch_probabilities) + { + len = strlen (filename); + da_file_name = (char *) alloca (len + 4); + strcpy (da_file_name, filename); + strip_off_ending (da_file_name, len); + strcat (da_file_name, ".da"); + if ((da_file = fopen (da_file_name, "r")) == 0) + warning ("file %s not found, execution counts assumed to be zero.", + da_file_name); + + /* The first word in the .da file gives the number of instrumented arcs, + which is not needed for our purposes. */ + + if (da_file) + __read_long (&len, da_file, 8); + } + + if (profile_arc_flag) + init_arc_profiler (); + + total_num_blocks = 0; + total_num_arcs = 0; + total_num_arcs_instrumented = 0; + total_num_blocks_created = 0; + total_num_passes = 0; + total_num_times_called = 0; + total_num_branches = 0; + total_num_never_executed = 0; + for (i = 0; i < 20; i++) + total_hist_br_prob[i] = 0; +} + +/* Performs file-level cleanup after branch-prob processing + is completed. */ + +void +end_branch_prob (dump_file) + FILE *dump_file; +{ + if (flag_test_coverage) + { + fclose (bb_file); + fclose (bbg_file); + } + + if (flag_branch_probabilities) + { + if (da_file) + { + long temp; + /* This seems slightly dangerous, as it presumes the EOF + flag will not be set until an attempt is made to read + past the end of the file. */ + if (feof (da_file)) + warning (".da file contents exhausted too early\n"); + /* Should be at end of file now. */ + if (__read_long (&temp, da_file, 8) == 0) + warning (".da file contents not exhausted\n"); + fclose (da_file); + } + } + + if (dump_file) + { + fprintf (dump_file, "\n"); + fprintf (dump_file, "Total number of blocks: %d\n", total_num_blocks); + fprintf (dump_file, "Total number of arcs: %d\n", total_num_arcs); + fprintf (dump_file, "Total number of instrumented arcs: %d\n", + total_num_arcs_instrumented); + fprintf (dump_file, "Total number of blocks created: %d\n", + total_num_blocks_created); + fprintf (dump_file, "Total number of graph solution passes: %d\n", + total_num_passes); + if (total_num_times_called != 0) + fprintf (dump_file, "Average number of graph solution passes: %d\n", + (total_num_passes + (total_num_times_called >> 1)) + / total_num_times_called); + fprintf (dump_file, "Total number of branches: %d\n", total_num_branches); + fprintf (dump_file, "Total number of branches never executed: %d\n", + total_num_never_executed); + if (total_num_branches) + { + int i; + + for (i = 0; i < 10; i++) + fprintf (dump_file, "%d%% branches in range %d-%d%%\n", + (total_hist_br_prob[i] + total_hist_br_prob[19-i]) * 100 + / total_num_branches, 5*i, 5*i+5); + } + } +} + +/* The label used by the arc profiling code. */ + +static rtx profiler_label; + +/* Initialize the profiler_label. */ + +static void +init_arc_profiler () +{ + /* Generate and save a copy of this so it can be shared. */ + char *name = xmalloc (20); + ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 2); + profiler_label = gen_rtx_SYMBOL_REF (Pmode, name); +} + +/* Output instructions as RTL to increment the arc execution count. */ + +static void +output_arc_profiler (arcno, insert_after) + int arcno; + rtx insert_after; +{ + rtx profiler_target_addr + = (arcno + ? gen_rtx_CONST (Pmode, + gen_rtx_PLUS (Pmode, profiler_label, + GEN_INT (LONG_TYPE_SIZE / BITS_PER_UNIT * arcno))) + : profiler_label); + enum machine_mode mode = mode_for_size (LONG_TYPE_SIZE, MODE_INT, 0); + rtx profiler_reg = gen_reg_rtx (mode); + rtx address_reg = gen_reg_rtx (Pmode); + rtx mem_ref, add_ref; + rtx sequence; + + /* In this case, reload can use explicitly mentioned hard registers for + reloads. It is not safe to output profiling code between a call + and the instruction that copies the result to a pseudo-reg. This + is because reload may allocate one of the profiling code pseudo-regs + to the return value reg, thus clobbering the return value. So we + must check for calls here, and emit the profiling code after the + instruction that uses the return value, if any. + + ??? The code here performs the same tests that reload does so hopefully + all the bases are covered. */ + + if (SMALL_REGISTER_CLASSES + && GET_CODE (insert_after) == CALL_INSN + && (GET_CODE (PATTERN (insert_after)) == SET + || (GET_CODE (PATTERN (insert_after)) == PARALLEL + && GET_CODE (XVECEXP (PATTERN (insert_after), 0, 0)) == SET))) + { + rtx return_reg; + rtx next_insert_after = next_nonnote_insn (insert_after); + + /* The first insn after the call may be a stack pop, skip it. */ + if (next_insert_after + && GET_CODE (next_insert_after) == INSN + && GET_CODE (PATTERN (next_insert_after)) == SET + && SET_DEST (PATTERN (next_insert_after)) == stack_pointer_rtx) + next_insert_after = next_nonnote_insn (next_insert_after); + + if (next_insert_after + && GET_CODE (next_insert_after) == INSN) + { + if (GET_CODE (PATTERN (insert_after)) == SET) + return_reg = SET_DEST (PATTERN (insert_after)); + else + return_reg = SET_DEST (XVECEXP (PATTERN (insert_after), 0, 0)); + + /* Now, NEXT_INSERT_AFTER may be an instruction that uses the + return value. However, it could also be something else, + like a CODE_LABEL, so check that the code is INSN. */ + if (next_insert_after != 0 + && GET_RTX_CLASS (GET_CODE (next_insert_after)) == 'i' + && reg_referenced_p (return_reg, PATTERN (next_insert_after))) + insert_after = next_insert_after; + } + } + + start_sequence (); + + emit_move_insn (address_reg, profiler_target_addr); + mem_ref = gen_rtx_MEM (mode, address_reg); + emit_move_insn (profiler_reg, mem_ref); + + add_ref = gen_rtx_PLUS (mode, profiler_reg, GEN_INT (1)); + emit_move_insn (profiler_reg, add_ref); + + /* This is the same rtx as above, but it is not legal to share this rtx. */ + mem_ref = gen_rtx_MEM (mode, address_reg); + emit_move_insn (mem_ref, profiler_reg); + + sequence = gen_sequence (); + end_sequence (); + emit_insn_after (sequence, insert_after); +} + +/* Output code for a constructor that will invoke __bb_init_func, if + this has not already been done. */ + +void +output_func_start_profiler () +{ + tree fnname, fndecl; + char *name, *cfnname; + rtx table_address; + enum machine_mode mode = mode_for_size (LONG_TYPE_SIZE, MODE_INT, 0); + int save_flag_inline_functions = flag_inline_functions; + + /* It's either already been output, or we don't need it because we're + not doing profile-arcs. */ + if (! need_func_profiler) + return; + + need_func_profiler = 0; + + /* Synthesize a constructor function to invoke __bb_init_func with a + pointer to this object file's profile block. */ + start_sequence (); + + /* Try and make a unique name given the "file function name". + + And no, I don't like this either. */ + + fnname = get_file_function_name ('I'); + cfnname = IDENTIFIER_POINTER (fnname); + name = xmalloc (strlen (cfnname) + 5); + sprintf (name, "%sGCOV",cfnname); + fnname = get_identifier (name); + free (name); + + fndecl = build_decl (FUNCTION_DECL, fnname, + build_function_type (void_type_node, NULL_TREE)); + DECL_EXTERNAL (fndecl) = 0; + TREE_PUBLIC (fndecl) = 1; + DECL_ASSEMBLER_NAME (fndecl) = fnname; + DECL_RESULT (fndecl) = build_decl (RESULT_DECL, NULL_TREE, void_type_node); + current_function_decl = fndecl; + pushlevel (0); + make_function_rtl (fndecl); + init_function_start (fndecl, input_filename, lineno); + expand_function_start (fndecl, 0); + + /* Actually generate the code to call __bb_init_func. */ + name = xmalloc (20); + ASM_GENERATE_INTERNAL_LABEL (name, "LPBX", 0); + table_address = force_reg (Pmode, gen_rtx_SYMBOL_REF (Pmode, name)); + emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__bb_init_func"), 0, + mode, 1, table_address, Pmode); + + expand_function_end (input_filename, lineno, 0); + poplevel (1, 0, 1); + + /* Since fndecl isn't in the list of globals, it would never be emitted + when it's considered to be 'safe' for inlining, so turn off + flag_inline_functions. */ + flag_inline_functions = 0; + + rest_of_compilation (fndecl); + + /* Reset flag_inline_functions to its original value. */ + flag_inline_functions = save_flag_inline_functions; + + if (! quiet_flag) + fflush (asm_out_file); + current_function_decl = NULL_TREE; + + assemble_constructor (IDENTIFIER_POINTER (DECL_NAME (fndecl))); +} |
