| /* Calculate branch probabilities, and basic block execution counts. |
| Copyright (C) 1990, 91, 92, 93, 94, 96, 1997 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 "rtl.h" |
| #include "flags.h" |
| #include "insn-flags.h" |
| #include "insn-config.h" |
| #include "output.h" |
| #include <stdio.h> |
| #include "tree.h" |
| #include "output.h" |
| #include "gcov-io.h" |
| |
| extern char * xmalloc (); |
| extern void free (); |
| |
| /* 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; |
| |
| int neg_one = -1; |
| int zero = 0; |
| int inverted; |
| rtx note; |
| |
| /* 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); |
| } |
| |
| /* 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 auxilliary |
| 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; |
| int dest; |
| rtx insn; |
| 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; |
| |
| /* 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. */ |
| |
| if (GET_CODE (pattern) == PARALLEL) |
| { |
| /* This assumes that PARALLEL jumps are tablejump entry |
| jumps. */ |
| /* 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 ((tem = SET_SRC (pattern)) |
| && GET_CODE (tem) == LABEL_REF) |
| dest = label_to_bb[CODE_LABEL_NUMBER (XEXP (tem, 0))]; |
| else |
| { |
| rtx label_ref; |
| |
| /* Must be an IF_THEN_ELSE branch. */ |
| if (GET_CODE (tem) != IF_THEN_ELSE) |
| abort (); |
| 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) |
| 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. |
| |
| Fallthough 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); |
| |
| /* 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_rtx (CONST_INT, VOIDmode, |
| 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; |
| |
| #ifdef SMALL_REGISTER_CLASSES |
| /* 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)); |
| |
| if (reg_referenced_p (return_reg, PATTERN (next_insert_after))) |
| insert_after = next_insert_after; |
| } |
| } |
| #endif |
| |
| 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; |
| |
| fflush (asm_out_file); |
| current_function_decl = NULL_TREE; |
| |
| assemble_constructor (IDENTIFIER_POINTER (DECL_NAME (fndecl))); |
| } |