From 6e537ce81f9e79b627e0b95162036304de028a4e Mon Sep 17 00:00:00 2001 From: hubicka Date: Wed, 18 Jul 2001 17:11:11 +0000 Subject: [PATCH] * flow.c (redirect_edge_and_branch): Bail out on complex edges. (try_optimize_cfg): Do not remove tail recursive labels before sibcall. * jump.c (mark_jump_label): Do not forward branches. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@44118 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ChangeLog | 7 +++++++ gcc/flow.c | 45 ++++++++++++++++++++++++++------------------- gcc/jump.c | 40 ---------------------------------------- 3 files changed, 33 insertions(+), 59 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 066b41200d8..e045d18fe68 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +Wed Jul 18 18:46:30 CEST 2001 Richard Henderson + Jan Hubicka + + * flow.c (redirect_edge_and_branch): Bail out on complex edges. + (try_optimize_cfg): Do not remove tail recursive labels before sibcall. + * jump.c (mark_jump_label): Do not forward branches. + Wed Jul 18 18:35:01 CEST 2001 Jan Hubicka * cse.c (delete_trivially_dead_insns): Delete the libcall block diff --git a/gcc/flow.c b/gcc/flow.c index 6e6c2b61d0b..06a10401f79 100644 --- a/gcc/flow.c +++ b/gcc/flow.c @@ -1777,6 +1777,9 @@ redirect_edge_and_branch (e, target) basic_block src = e->src; rtx insn = src->end; + if (e->flags & EDGE_COMPLEX) + return false; + if (try_redirect_by_replacing_jump (e, target)) return true; /* Do this fast path late, as we want above code to simplify for cases @@ -3683,30 +3686,15 @@ try_optimize_cfg (mode) changed = 1; b = c; } - /* The fallthru forwarder block can be deleted. */ - if (b->pred->pred_next == NULL - && forwarder_block_p (b) - && n_basic_blocks > 1 - && (b->pred->flags & EDGE_FALLTHRU) - && (b->succ->flags & EDGE_FALLTHRU)) - { - if (rtl_dump_file) - fprintf (rtl_dump_file, "Deleting fallthru block %i.\n", - b->index); - c = BASIC_BLOCK (i ? i - 1 : i + 1); - redirect_edge_succ (b->pred, b->succ->dest); - flow_delete_block (b); - changed = 1; - b = c; - } - /* Remove code labels no longer used. Don't do the optimization before sibling calls are discovered, as some branches may be hidden inside CALL_PLACEHOLDERs. */ - if (!(mode & CLEANUP_PRE_SIBCALL) - && b->pred->pred_next == NULL + if (b->pred->pred_next == NULL && (b->pred->flags & EDGE_FALLTHRU) + && !(b->pred->flags & EDGE_COMPLEX) && GET_CODE (b->head) == CODE_LABEL + && (!(mode & CLEANUP_PRE_SIBCALL) + || !tail_recursion_label_p (b->head)) /* If previous block does end with condjump jumping to next BB, we can't delete the label. */ && (b->pred->src == ENTRY_BLOCK_PTR @@ -3719,12 +3707,31 @@ try_optimize_cfg (mode) fprintf (rtl_dump_file, "Deleted label in block %i.\n", b->index); } + /* The fallthru forwarder block can be deleted. */ + if (b->pred->pred_next == NULL + && forwarder_block_p (b) + && n_basic_blocks > 1 + && (b->pred->flags & EDGE_FALLTHRU) + && (b->succ->flags & EDGE_FALLTHRU) + && GET_CODE (b->head) != CODE_LABEL) + { + if (rtl_dump_file) + fprintf (rtl_dump_file, "Deleting fallthru block %i.\n", + b->index); + c = BASIC_BLOCK (i ? i - 1 : i + 1); + redirect_edge_succ (b->pred, b->succ->dest); + flow_delete_block (b); + changed = 1; + b = c; + } + /* A loop because chains of blocks might be combineable. */ while ((s = b->succ) != NULL && s->succ_next == NULL && (s->flags & EDGE_EH) == 0 && (c = s->dest) != EXIT_BLOCK_PTR + && !(s->flags & EDGE_COMPLEX) && c->pred->pred_next == NULL /* If the jump insn has side effects, we can't kill the edge. */ diff --git a/gcc/jump.c b/gcc/jump.c index 20e0bc783c8..afc37f9b8b4 100644 --- a/gcc/jump.c +++ b/gcc/jump.c @@ -1999,8 +1999,6 @@ mark_jump_label (x, insn, in_mem) case LABEL_REF: { rtx label = XEXP (x, 0); - rtx olabel = label; - rtx next; /* Ignore remaining references to unreachable labels that have been deleted. */ @@ -2015,23 +2013,6 @@ mark_jump_label (x, insn, in_mem) if (LABEL_REF_NONLOCAL_P (x)) break; - /* If there are other labels following this one, - replace it with the last of the consecutive labels. */ - for (next = NEXT_INSN (label); next; next = NEXT_INSN (next)) - { - if (GET_CODE (next) == CODE_LABEL) - label = next; - else if (GET_CODE (next) != NOTE) - break; - else if ((NOTE_LINE_NUMBER (next) == NOTE_INSN_LOOP_BEG - || NOTE_LINE_NUMBER (next) == NOTE_INSN_FUNCTION_END - /* ??? Optional. Disables some optimizations, but - makes gcov output more accurate with -O. */ - || (flag_test_coverage - && NOTE_LINE_NUMBER (next) > 0))) - break; - } - XEXP (x, 0) = label; if (! insn || ! INSN_DELETED_P (insn)) ++LABEL_NUSES (label); @@ -2042,27 +2023,6 @@ mark_jump_label (x, insn, in_mem) JUMP_LABEL (insn) = label; else { - /* If we've changed the label, update notes accordingly. */ - if (label != olabel) - { - rtx note; - - /* We may have a REG_LABEL note to indicate that this - instruction uses the label. */ - note = find_reg_note (insn, REG_LABEL, olabel); - if (note) - XEXP (note, 0) = label; - - /* We may also have a REG_EQUAL note to indicate that - a register is being set to the address of the - label. */ - note = find_reg_note (insn, REG_EQUAL, NULL_RTX); - if (note - && GET_CODE (XEXP (note, 0)) == LABEL_REF - && XEXP (XEXP (note, 0), 0) == olabel) - XEXP (XEXP (note, 0), 0) = label; - } - /* Add a REG_LABEL note for LABEL unless there already is one. All uses of a label, except for labels that are the targets of jumps, must have a -- 2.11.0