From: Bernd Schmidt Date: Thu, 14 Jul 2011 11:55:59 +0000 (+0000) Subject: haifa-sched.c (schedule_insns): Remove outdated comment. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=b953c2b834c1f92f20729a51b4cd4d15b2426d7a;p=gcc.git haifa-sched.c (schedule_insns): Remove outdated comment. * haifa-sched.c (schedule_insns): Remove outdated comment. (schedule_block): When computing a known value for TODO_SPEC, just set it rather than using logical operations. (try_ready): Likewise. Use a local variable rather than a pointer to TODO_SPEC. Reorder an if statement to move the easy case to the then block. * sched-deps.c (dep_spec_p): New static function. (update_dep): Use it to decide whether to call change_spec_dep_to_hard. (get_back_and_forw_lists): Use it. (sd_resolve_dep): Likewise. (init_dep): If !USE_DEPS_LIST, use zero to initialize status. (haifa_note_mem_dep): Likewise. (check_dep): Likewise. (sd_add_dep): Also clear SPECULATIVE bits if not DO_SPECULATION. (sched_free_deps): Free in two passes. From-SVN: r176271 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index f003ea9ed1f..2341964fe70 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,22 @@ +2011-07-14 Bernd Schmidt + + * haifa-sched.c (schedule_insns): Remove outdated comment. + (schedule_block): When computing a known value for TODO_SPEC, + just set it rather than using logical operations. + (try_ready): Likewise. Use a local variable rather than a + pointer to TODO_SPEC. Reorder an if statement to move the + easy case to the then block. + * sched-deps.c (dep_spec_p): New static function. + (update_dep): Use it to decide whether to call + change_spec_dep_to_hard. + (get_back_and_forw_lists): Use it. + (sd_resolve_dep): Likewise. + (init_dep): If !USE_DEPS_LIST, use zero to initialize status. + (haifa_note_mem_dep): Likewise. + (check_dep): Likewise. + (sd_add_dep): Also clear SPECULATIVE bits if not DO_SPECULATION. + (sched_free_deps): Free in two passes. + 2011-07-14 Richard Sandiford PR middle-end/49736 diff --git a/gcc/haifa-sched.c b/gcc/haifa-sched.c index 3630924fa23..2bef53071cf 100644 --- a/gcc/haifa-sched.c +++ b/gcc/haifa-sched.c @@ -2004,18 +2004,6 @@ schedule_insn (rtx insn) } } - /* This is the place where scheduler doesn't *basically* need backward and - forward dependencies for INSN anymore. Nevertheless they are used in - heuristics in rank_for_schedule (), early_queue_to_ready () and in - some targets (e.g. rs6000). Thus the earliest place where we *can* - remove dependencies is after targetm.sched.finish () call in - schedule_block (). But, on the other side, the safest place to remove - dependencies is when we are finishing scheduling entire region. As we - don't generate [many] dependencies during scheduling itself, we won't - need memory until beginning of next region. - Bottom line: Dependencies are removed for all insns in the end of - scheduling the region. */ - /* Annotate the instruction with issue information -- TImode indicates that the instruction is expected not to be able to issue on the same cycle as the previous insn. A machine @@ -3906,7 +3894,7 @@ schedule_block (basic_block *target_bb) /* We normally get here only if we don't want to move insn from the split block. */ { - TODO_SPEC (insn) = (TODO_SPEC (insn) & ~SPECULATIVE) | HARD_DEP; + TODO_SPEC (insn) = HARD_DEP; goto restart_choose_ready; } @@ -4049,7 +4037,7 @@ schedule_block (basic_block *target_bb) x = ready_element (&ready, i); QUEUE_INDEX (x) = QUEUE_NOWHERE; - TODO_SPEC (x) = (TODO_SPEC (x) & ~SPECULATIVE) | HARD_DEP; + TODO_SPEC (x) = HARD_DEP; } if (q_size) @@ -4062,7 +4050,7 @@ schedule_block (basic_block *target_bb) x = XEXP (link, 0); QUEUE_INDEX (x) = QUEUE_NOWHERE; - TODO_SPEC (x) = (TODO_SPEC (x) & ~SPECULATIVE) | HARD_DEP; + TODO_SPEC (x) = HARD_DEP; } free_INSN_LIST_list (&insn_queue[i]); } @@ -4492,10 +4480,9 @@ static int haifa_speculate_insn (rtx, ds_t, rtx *); int try_ready (rtx next) { - ds_t old_ts, *ts; + ds_t old_ts, new_ts; - ts = &TODO_SPEC (next); - old_ts = *ts; + old_ts = TODO_SPEC (next); gcc_assert (!(old_ts & ~(SPECULATIVE | HARD_DEP)) && ((old_ts & HARD_DEP) @@ -4503,22 +4490,15 @@ try_ready (rtx next) if (sd_lists_empty_p (next, SD_LIST_BACK)) /* NEXT has all its dependencies resolved. */ - { - /* Remove HARD_DEP bit from NEXT's status. */ - *ts &= ~HARD_DEP; - - if (current_sched_info->flags & DO_SPECULATION) - /* Remove all speculative bits from NEXT's status. */ - *ts &= ~SPECULATIVE; - } + new_ts = 0; else { /* One of the NEXT's dependencies has been resolved. Recalculate NEXT's status. */ - *ts &= ~SPECULATIVE & ~HARD_DEP; - - if (sd_lists_empty_p (next, SD_LIST_HARD_BACK)) + if (!sd_lists_empty_p (next, SD_LIST_HARD_BACK)) + new_ts = HARD_DEP; + else /* Now we've got NEXT with speculative deps only. 1. Look at the deps to see what we have to do. 2. Check if we can do 'todo'. */ @@ -4527,6 +4507,8 @@ try_ready (rtx next) dep_t dep; bool first_p = true; + new_ts = 0; + FOR_EACH_DEP (next, SD_LIST_BACK, sd_it, dep) { ds_t ds = DEP_STATUS (dep) & SPECULATIVE; @@ -4539,25 +4521,23 @@ try_ready (rtx next) { first_p = false; - *ts = ds; + new_ts = ds; } else - *ts = ds_merge (*ts, ds); + new_ts = ds_merge (new_ts, ds); } - if (ds_weak (*ts) < spec_info->data_weakness_cutoff) + if (ds_weak (new_ts) < spec_info->data_weakness_cutoff) /* Too few points. */ - *ts = (*ts & ~SPECULATIVE) | HARD_DEP; + new_ts = HARD_DEP; } - else - *ts |= HARD_DEP; } - if (*ts & HARD_DEP) - gcc_assert (*ts == old_ts + if (new_ts & HARD_DEP) + gcc_assert (new_ts == HARD_DEP && new_ts == old_ts && QUEUE_INDEX (next) == QUEUE_NOWHERE); else if (current_sched_info->new_ready) - *ts = current_sched_info->new_ready (next, *ts); + new_ts = current_sched_info->new_ready (next, new_ts); /* * if !(old_ts & SPECULATIVE) (e.g. HARD_DEP or 0), then insn might have its original pattern or changed (speculative) one. This is due @@ -4565,29 +4545,29 @@ try_ready (rtx next) * But if (old_ts & SPECULATIVE), then we are pretty sure that insn has speculative pattern. - We can't assert (!(*ts & HARD_DEP) || *ts == old_ts) here because + We can't assert (!(new_ts & HARD_DEP) || new_ts == old_ts) here because control-speculative NEXT could have been discarded by sched-rgn.c (the same case as when discarded by can_schedule_ready_p ()). */ - if ((*ts & SPECULATIVE) - /* If (old_ts == *ts), then (old_ts & SPECULATIVE) and we don't + if ((new_ts & SPECULATIVE) + /* If (old_ts == new_ts), then (old_ts & SPECULATIVE) and we don't need to change anything. */ - && *ts != old_ts) + && new_ts != old_ts) { int res; rtx new_pat; - gcc_assert ((*ts & SPECULATIVE) && !(*ts & ~SPECULATIVE)); + gcc_assert (!(new_ts & ~SPECULATIVE)); - res = haifa_speculate_insn (next, *ts, &new_pat); + res = haifa_speculate_insn (next, new_ts, &new_pat); switch (res) { case -1: /* It would be nice to change DEP_STATUS of all dependences, - which have ((DEP_STATUS & SPECULATIVE) == *ts) to HARD_DEP, + which have ((DEP_STATUS & SPECULATIVE) == new_ts) to HARD_DEP, so we won't reanalyze anything. */ - *ts = (*ts & ~SPECULATIVE) | HARD_DEP; + new_ts = HARD_DEP; break; case 0: @@ -4611,14 +4591,16 @@ try_ready (rtx next) } } - /* We need to restore pattern only if (*ts == 0), because otherwise it is - either correct (*ts & SPECULATIVE), - or we simply don't care (*ts & HARD_DEP). */ + /* We need to restore pattern only if (new_ts == 0), because otherwise it is + either correct (new_ts & SPECULATIVE), + or we simply don't care (new_ts & HARD_DEP). */ gcc_assert (!ORIG_PAT (next) || !IS_SPECULATION_BRANCHY_CHECK_P (next)); - if (*ts & HARD_DEP) + TODO_SPEC (next) = new_ts; + + if (new_ts & HARD_DEP) { /* We can't assert (QUEUE_INDEX (next) == QUEUE_NOWHERE) here because control-speculative NEXT could have been discarded by sched-rgn.c @@ -4628,7 +4610,8 @@ try_ready (rtx next) change_queue_index (next, QUEUE_NOWHERE); return -1; } - else if (!(*ts & BEGIN_SPEC) && ORIG_PAT (next) && !IS_SPECULATION_CHECK_P (next)) + else if (!(new_ts & BEGIN_SPEC) + && ORIG_PAT (next) && !IS_SPECULATION_CHECK_P (next)) /* We should change pattern of every previously speculative instruction - and we determine if NEXT was speculative by using ORIG_PAT field. Except one case - speculation checks have ORIG_PAT @@ -4640,18 +4623,16 @@ try_ready (rtx next) if (sched_verbose >= 2) { - int s = TODO_SPEC (next); - fprintf (sched_dump, ";;\t\tdependencies resolved: insn %s", (*current_sched_info->print_insn) (next, 0)); if (spec_info && spec_info->dump) { - if (s & BEGIN_DATA) + if (new_ts & BEGIN_DATA) fprintf (spec_info->dump, "; data-spec;"); - if (s & BEGIN_CONTROL) + if (new_ts & BEGIN_CONTROL) fprintf (spec_info->dump, "; control-spec;"); - if (s & BE_IN_CONTROL) + if (new_ts & BE_IN_CONTROL) fprintf (spec_info->dump, "; in-control-spec;"); } diff --git a/gcc/sched-deps.c b/gcc/sched-deps.c index 0bba96c995e..09523e78749 100644 --- a/gcc/sched-deps.c +++ b/gcc/sched-deps.c @@ -121,7 +121,7 @@ init_dep (dep_t dep, rtx pro, rtx con, enum reg_note kind) if ((current_sched_info->flags & USE_DEPS_LIST)) ds = dk_to_ds (kind); else - ds = -1; + ds = 0; init_dep_1 (dep, pro, con, kind, ds); } @@ -414,6 +414,16 @@ clear_deps_list (deps_list_t l) while (1); } +/* Decide whether a dependency should be treated as a hard or a speculative + dependency. */ +static bool +dep_spec_p (dep_t dep) +{ + if (current_sched_info->flags & DO_SPECULATION) + return (DEP_STATUS (dep) & SPECULATIVE) != 0; + return false; +} + static regset reg_pending_sets; static regset reg_pending_clobbers; static regset reg_pending_uses; @@ -1064,6 +1074,7 @@ update_dep (dep_t dep, dep_t new_dep, { enum DEPS_ADJUST_RESULT res = DEP_PRESENT; enum reg_note old_type = DEP_TYPE (dep); + bool was_spec = dep_spec_p (dep); /* If this is a more restrictive type of dependence than the existing one, then change the existing dependence to this @@ -1082,20 +1093,13 @@ update_dep (dep_t dep, dep_t new_dep, ds_t new_status = ds | dep_status; if (new_status & SPECULATIVE) - /* Either existing dep or a dep we're adding or both are - speculative. */ { + /* Either existing dep or a dep we're adding or both are + speculative. */ if (!(ds & SPECULATIVE) || !(dep_status & SPECULATIVE)) /* The new dep can't be speculative. */ - { - new_status &= ~SPECULATIVE; - - if (dep_status & SPECULATIVE) - /* The old dep was speculative, but now it - isn't. */ - change_spec_dep_to_hard (sd_it); - } + new_status &= ~SPECULATIVE; else { /* Both are speculative. Merge probabilities. */ @@ -1120,6 +1124,10 @@ update_dep (dep_t dep, dep_t new_dep, } } + if (was_spec && !dep_spec_p (dep)) + /* The old dep was speculative, but now it isn't. */ + change_spec_dep_to_hard (sd_it); + if (true_dependency_cache != NULL && res == DEP_CHANGED) update_dependency_caches (dep, old_type); @@ -1220,8 +1228,7 @@ get_back_and_forw_lists (dep_t dep, bool resolved_p, if (!resolved_p) { - if ((current_sched_info->flags & DO_SPECULATION) - && (DEP_STATUS (dep) & SPECULATIVE)) + if (dep_spec_p (dep)) *back_list_ptr = INSN_SPEC_BACK_DEPS (con); else *back_list_ptr = INSN_HARD_BACK_DEPS (con); @@ -1248,8 +1255,8 @@ sd_add_dep (dep_t dep, bool resolved_p) gcc_assert (INSN_P (insn) && INSN_P (elem) && insn != elem); - if ((current_sched_info->flags & DO_SPECULATION) - && !sched_insn_is_legitimate_for_speculation_p (insn, DEP_STATUS (dep))) + if ((current_sched_info->flags & DO_SPECULATION) == 0 + || !sched_insn_is_legitimate_for_speculation_p (insn, DEP_STATUS (dep))) DEP_STATUS (dep) &= ~SPECULATIVE; copy_dep (DEP_NODE_DEP (n), dep); @@ -1289,8 +1296,7 @@ sd_resolve_dep (sd_iterator_def sd_it) rtx pro = DEP_PRO (dep); rtx con = DEP_CON (dep); - if ((current_sched_info->flags & DO_SPECULATION) - && (DEP_STATUS (dep) & SPECULATIVE)) + if (dep_spec_p (dep)) move_dep_link (DEP_NODE_BACK (node), INSN_SPEC_BACK_DEPS (con), INSN_RESOLVED_BACK_DEPS (con)); else @@ -1705,7 +1711,7 @@ haifa_note_mem_dep (rtx mem, rtx pending_mem, rtx pending_insn, ds_t ds) dep_def _dep, *dep = &_dep; init_dep_1 (dep, pending_insn, cur_insn, ds_to_dt (ds), - current_sched_info->flags & USE_DEPS_LIST ? ds : -1); + current_sched_info->flags & USE_DEPS_LIST ? ds : 0); maybe_add_or_update_dep_1 (dep, false, pending_mem, mem); } @@ -3512,18 +3518,23 @@ sched_free_deps (rtx head, rtx tail, bool resolved_p) rtx insn; rtx next_tail = NEXT_INSN (tail); + /* We make two passes since some insns may be scheduled before their + dependencies are resolved. */ for (insn = head; insn != next_tail; insn = NEXT_INSN (insn)) if (INSN_P (insn) && INSN_LUID (insn) > 0) { - /* Clear resolved back deps together with its dep_nodes. */ - delete_dep_nodes_in_back_deps (insn, resolved_p); - /* Clear forward deps and leave the dep_nodes to the corresponding back_deps list. */ if (resolved_p) clear_deps_list (INSN_RESOLVED_FORW_DEPS (insn)); else clear_deps_list (INSN_FORW_DEPS (insn)); + } + for (insn = head; insn != next_tail; insn = NEXT_INSN (insn)) + if (INSN_P (insn) && INSN_LUID (insn) > 0) + { + /* Clear resolved back deps together with its dep_nodes. */ + delete_dep_nodes_in_back_deps (insn, resolved_p); sd_finish_insn (insn); } @@ -4164,7 +4175,7 @@ check_dep (dep_t dep, bool relaxed_p) if (!(current_sched_info->flags & USE_DEPS_LIST)) { - gcc_assert (ds == -1); + gcc_assert (ds == 0); return; }