diff options
Diffstat (limited to 'gcc/profile.c')
| -rw-r--r-- | gcc/profile.c | 82 |
1 files changed, 43 insertions, 39 deletions
diff --git a/gcc/profile.c b/gcc/profile.c index 99ddd3bc7d4..afabe20a42f 100644 --- a/gcc/profile.c +++ b/gcc/profile.c @@ -674,22 +674,47 @@ compute_branch_probabilities () FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb) { edge e; - gcov_type total; rtx note; - total = bb->count; - if (total) + if (bb->count < 0) { - for (e = bb->succ; e; e = e->succ_next) + error ("corrupted profile info: number of iterations for basic block %d thought to be %i", + bb->index, (int)bb->count); + bb->count = 0; + } + for (e = bb->succ; e; e = e->succ_next) + { + /* Function may return twice in the cased the called fucntion is + setjmp or calls fork, but we can't represent this by extra + edge from the entry, since extra edge from the exit is + already present. We get negative frequency from the entry + point. */ + if ((e->count < 0 + && e->dest == EXIT_BLOCK_PTR) + || (e->count > bb->count + && e->dest != EXIT_BLOCK_PTR)) { - e->probability = (e->count * REG_BR_PROB_BASE + total / 2) / total; - if (e->probability < 0 || e->probability > REG_BR_PROB_BASE) - { - error ("corrupted profile info: prob for %d-%d thought to be %d", - e->src->index, e->dest->index, e->probability); - e->probability = REG_BR_PROB_BASE / 2; - } + rtx insn = bb->end; + + while (GET_CODE (insn) != CALL_INSN + && insn != bb->head + && keep_with_call_p (insn)) + insn = PREV_INSN (insn); + if (GET_CODE (insn) == CALL_INSN) + e->count = e->count < 0 ? 0 : bb->count; } + if (e->count < 0 || e->count > bb->count) + { + error ("corrupted profile info: number of executions for edge %d-%d thought to be %i", + e->src->index, e->dest->index, + (int)e->count); + e->count = bb->count / 2; + } + } + if (bb->count) + { + for (e = bb->succ; e; e = e->succ_next) + e->probability = (e->count * REG_BR_PROB_BASE + bb->count / 2) / bb->count; if (bb->index >= 0 && any_condjump_p (bb->end) && bb->succ->succ_next) @@ -730,6 +755,8 @@ compute_branch_probabilities () calls). */ else { + int total = 0; + for (e = bb->succ; e; e = e->succ_next) if (!(e->flags & (EDGE_COMPLEX | EDGE_FAKE))) total ++; @@ -873,36 +900,13 @@ branch_prob () { int need_exit_edge = 0, need_entry_edge = 0; int have_exit_edge = 0, have_entry_edge = 0; - rtx insn; edge e; - /* Add fake edges from entry block to the call insns that may return - twice. The CFG is not quite correct then, as call insn plays more - role of CODE_LABEL, but for our purposes, everything should be OK, - as we never insert code to the beginning of basic block. */ - for (insn = bb->head; insn != NEXT_INSN (bb->end); - insn = NEXT_INSN (insn)) - { - if (GET_CODE (insn) == CALL_INSN - && find_reg_note (insn, REG_SETJMP, NULL)) - { - if (GET_CODE (bb->head) == CODE_LABEL - || insn != NEXT_INSN (bb->head)) - { - e = split_block (bb, PREV_INSN (insn)); - make_edge (ENTRY_BLOCK_PTR, e->dest, EDGE_FAKE); - break; - } - else - { - /* We should not get abort here, as call to setjmp should not - be the very first instruction of function. */ - if (bb == ENTRY_BLOCK_PTR) - abort (); - make_edge (ENTRY_BLOCK_PTR, bb, EDGE_FAKE); - } - } - } + /* Functions returning multiple times are not handled by extra edges. + Instead we simply allow negative counts on edges from exit to the + block past call and corresponding probabilities. We can't go + with the extra edges because that would result in flowgraph that + needs to have fake edges outside the spanning tree. */ for (e = bb->succ; e; e = e->succ_next) { |
