From c2fc5456232936eae2354dbdce04084ab03e09a1 Mon Sep 17 00:00:00 2001 From: "J\"orn Rennecke" Date: Mon, 19 Dec 2005 14:36:59 +0000 Subject: [PATCH] re PR rtl-optimization/20070 (If-conversion can't match equivalent code, and cross-jumping only works for literal matches) * cfgcleanup.c: Temporarily revert patches for PR 20070 till Bernd comes back. From-SVN: r108792 --- gcc/ChangeLog | 5 + gcc/cfgcleanup.c | 561 +++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 470 insertions(+), 96 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1ceca21b50d..f696975b60b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2005-12-19 J"orn Rennecke + + * cfgcleanup.c: Temporarily revert patches for PR 20070 till Bernd + comes back. + 2005-12-19 J"orn Rennecke * struct-equiv.c (struct_equiv_improve_checkpoint): Fix sets_cc0_p diff --git a/gcc/cfgcleanup.c b/gcc/cfgcleanup.c index 8443451a42f..8bc49a2abd8 100644 --- a/gcc/cfgcleanup.c +++ b/gcc/cfgcleanup.c @@ -60,7 +60,9 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA static bool first_pass; static bool try_crossjump_to_edge (int, edge, edge); static bool try_crossjump_bb (int, basic_block); -static bool outgoing_edges_match (int *, struct equiv_info *); +static bool outgoing_edges_match (int, basic_block, basic_block); +static int flow_find_cross_jump (int, basic_block, basic_block, rtx *, rtx *); +static bool old_insns_match_p (int, rtx, rtx); static void merge_blocks_move_predecessor_nojumps (basic_block, basic_block); static void merge_blocks_move_successor_nojumps (basic_block, basic_block); @@ -72,6 +74,7 @@ static bool mark_effect (rtx, bitmap); static void notice_new_block (basic_block); static void update_forwarder_flag (basic_block); static int mentions_nonequal_regs (rtx *, void *); +static void merge_memattrs (rtx, rtx); /* Set flags for newly created block. */ @@ -878,6 +881,319 @@ merge_blocks_move (edge e, basic_block b, basic_block c, int mode) return NULL; } + +/* Removes the memory attributes of MEM expression + if they are not equal. */ + +void +merge_memattrs (rtx x, rtx y) +{ + int i; + int j; + enum rtx_code code; + const char *fmt; + + if (x == y) + return; + if (x == 0 || y == 0) + return; + + code = GET_CODE (x); + + if (code != GET_CODE (y)) + return; + + if (GET_MODE (x) != GET_MODE (y)) + return; + + if (code == MEM && MEM_ATTRS (x) != MEM_ATTRS (y)) + { + if (! MEM_ATTRS (x)) + MEM_ATTRS (y) = 0; + else if (! MEM_ATTRS (y)) + MEM_ATTRS (x) = 0; + else + { + rtx mem_size; + + if (MEM_ALIAS_SET (x) != MEM_ALIAS_SET (y)) + { + set_mem_alias_set (x, 0); + set_mem_alias_set (y, 0); + } + + if (! mem_expr_equal_p (MEM_EXPR (x), MEM_EXPR (y))) + { + set_mem_expr (x, 0); + set_mem_expr (y, 0); + set_mem_offset (x, 0); + set_mem_offset (y, 0); + } + else if (MEM_OFFSET (x) != MEM_OFFSET (y)) + { + set_mem_offset (x, 0); + set_mem_offset (y, 0); + } + + if (!MEM_SIZE (x)) + mem_size = NULL_RTX; + else if (!MEM_SIZE (y)) + mem_size = NULL_RTX; + else + mem_size = GEN_INT (MAX (INTVAL (MEM_SIZE (x)), + INTVAL (MEM_SIZE (y)))); + set_mem_size (x, mem_size); + set_mem_size (y, mem_size); + + set_mem_align (x, MIN (MEM_ALIGN (x), MEM_ALIGN (y))); + set_mem_align (y, MEM_ALIGN (x)); + } + } + + fmt = GET_RTX_FORMAT (code); + for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) + { + switch (fmt[i]) + { + case 'E': + /* Two vectors must have the same length. */ + if (XVECLEN (x, i) != XVECLEN (y, i)) + return; + + for (j = 0; j < XVECLEN (x, i); j++) + merge_memattrs (XVECEXP (x, i, j), XVECEXP (y, i, j)); + + break; + + case 'e': + merge_memattrs (XEXP (x, i), XEXP (y, i)); + } + } + return; +} + + +/* Return true if I1 and I2 are equivalent and thus can be crossjumped. */ + +static bool +old_insns_match_p (int mode ATTRIBUTE_UNUSED, rtx i1, rtx i2) +{ + rtx p1, p2; + + /* Verify that I1 and I2 are equivalent. */ + if (GET_CODE (i1) != GET_CODE (i2)) + return false; + + p1 = PATTERN (i1); + p2 = PATTERN (i2); + + if (GET_CODE (p1) != GET_CODE (p2)) + return false; + + /* If this is a CALL_INSN, compare register usage information. + If we don't check this on stack register machines, the two + CALL_INSNs might be merged leaving reg-stack.c with mismatching + numbers of stack registers in the same basic block. + If we don't check this on machines with delay slots, a delay slot may + be filled that clobbers a parameter expected by the subroutine. + + ??? We take the simple route for now and assume that if they're + equal, they were constructed identically. */ + + if (CALL_P (i1) + && (!rtx_equal_p (CALL_INSN_FUNCTION_USAGE (i1), + CALL_INSN_FUNCTION_USAGE (i2)) + || SIBLING_CALL_P (i1) != SIBLING_CALL_P (i2))) + return false; + +#ifdef STACK_REGS + /* If cross_jump_death_matters is not 0, the insn's mode + indicates whether or not the insn contains any stack-like + regs. */ + + if ((mode & CLEANUP_POST_REGSTACK) && stack_regs_mentioned (i1)) + { + /* If register stack conversion has already been done, then + death notes must also be compared before it is certain that + the two instruction streams match. */ + + rtx note; + HARD_REG_SET i1_regset, i2_regset; + + CLEAR_HARD_REG_SET (i1_regset); + CLEAR_HARD_REG_SET (i2_regset); + + for (note = REG_NOTES (i1); note; note = XEXP (note, 1)) + if (REG_NOTE_KIND (note) == REG_DEAD && STACK_REG_P (XEXP (note, 0))) + SET_HARD_REG_BIT (i1_regset, REGNO (XEXP (note, 0))); + + for (note = REG_NOTES (i2); note; note = XEXP (note, 1)) + if (REG_NOTE_KIND (note) == REG_DEAD && STACK_REG_P (XEXP (note, 0))) + SET_HARD_REG_BIT (i2_regset, REGNO (XEXP (note, 0))); + + GO_IF_HARD_REG_EQUAL (i1_regset, i2_regset, done); + + return false; + + done: + ; + } +#endif + + if (reload_completed + ? rtx_renumbered_equal_p (p1, p2) : rtx_equal_p (p1, p2)) + return true; + + /* Do not do EQUIV substitution after reload. First, we're undoing the + work of reload_cse. Second, we may be undoing the work of the post- + reload splitting pass. */ + /* ??? Possibly add a new phase switch variable that can be used by + targets to disallow the troublesome insns after splitting. */ + if (!reload_completed) + { + /* The following code helps take care of G++ cleanups. */ + rtx equiv1 = find_reg_equal_equiv_note (i1); + rtx equiv2 = find_reg_equal_equiv_note (i2); + + if (equiv1 && equiv2 + /* If the equivalences are not to a constant, they may + reference pseudos that no longer exist, so we can't + use them. */ + && (! reload_completed + || (CONSTANT_P (XEXP (equiv1, 0)) + && rtx_equal_p (XEXP (equiv1, 0), XEXP (equiv2, 0))))) + { + rtx s1 = single_set (i1); + rtx s2 = single_set (i2); + if (s1 != 0 && s2 != 0 + && rtx_renumbered_equal_p (SET_DEST (s1), SET_DEST (s2))) + { + validate_change (i1, &SET_SRC (s1), XEXP (equiv1, 0), 1); + validate_change (i2, &SET_SRC (s2), XEXP (equiv2, 0), 1); + if (! rtx_renumbered_equal_p (p1, p2)) + cancel_changes (0); + else if (apply_change_group ()) + return true; + } + } + } + + return false; +} + +/* Look through the insns at the end of BB1 and BB2 and find the longest + sequence that are equivalent. Store the first insns for that sequence + in *F1 and *F2 and return the sequence length. + + To simplify callers of this function, if the blocks match exactly, + store the head of the blocks in *F1 and *F2. */ + +static int +flow_find_cross_jump (int mode ATTRIBUTE_UNUSED, basic_block bb1, + basic_block bb2, rtx *f1, rtx *f2) +{ + rtx i1, i2, last1, last2, afterlast1, afterlast2; + int ninsns = 0; + + /* Skip simple jumps at the end of the blocks. Complex jumps still + need to be compared for equivalence, which we'll do below. */ + + i1 = BB_END (bb1); + last1 = afterlast1 = last2 = afterlast2 = NULL_RTX; + if (onlyjump_p (i1) + || (returnjump_p (i1) && !side_effects_p (PATTERN (i1)))) + { + last1 = i1; + i1 = PREV_INSN (i1); + } + + i2 = BB_END (bb2); + if (onlyjump_p (i2) + || (returnjump_p (i2) && !side_effects_p (PATTERN (i2)))) + { + last2 = i2; + /* Count everything except for unconditional jump as insn. */ + if (!simplejump_p (i2) && !returnjump_p (i2) && last1) + ninsns++; + i2 = PREV_INSN (i2); + } + + while (true) + { + /* Ignore notes. */ + while (!INSN_P (i1) && i1 != BB_HEAD (bb1)) + i1 = PREV_INSN (i1); + + while (!INSN_P (i2) && i2 != BB_HEAD (bb2)) + i2 = PREV_INSN (i2); + + if (i1 == BB_HEAD (bb1) || i2 == BB_HEAD (bb2)) + break; + + if (!old_insns_match_p (mode, i1, i2)) + break; + + merge_memattrs (i1, i2); + + /* Don't begin a cross-jump with a NOTE insn. */ + if (INSN_P (i1)) + { + /* If the merged insns have different REG_EQUAL notes, then + remove them. */ + rtx equiv1 = find_reg_equal_equiv_note (i1); + rtx equiv2 = find_reg_equal_equiv_note (i2); + + if (equiv1 && !equiv2) + remove_note (i1, equiv1); + else if (!equiv1 && equiv2) + remove_note (i2, equiv2); + else if (equiv1 && equiv2 + && !rtx_equal_p (XEXP (equiv1, 0), XEXP (equiv2, 0))) + { + remove_note (i1, equiv1); + remove_note (i2, equiv2); + } + + afterlast1 = last1, afterlast2 = last2; + last1 = i1, last2 = i2; + ninsns++; + } + + i1 = PREV_INSN (i1); + i2 = PREV_INSN (i2); + } + +#ifdef HAVE_cc0 + /* Don't allow the insn after a compare to be shared by + cross-jumping unless the compare is also shared. */ + if (ninsns && reg_mentioned_p (cc0_rtx, last1) && ! sets_cc0_p (last1)) + last1 = afterlast1, last2 = afterlast2, ninsns--; +#endif + + /* Include preceding notes and labels in the cross-jump. One, + this may bring us to the head of the blocks as requested above. + Two, it keeps line number notes as matched as may be. */ + if (ninsns) + { + while (last1 != BB_HEAD (bb1) && !INSN_P (PREV_INSN (last1))) + last1 = PREV_INSN (last1); + + if (last1 != BB_HEAD (bb1) && LABEL_P (PREV_INSN (last1))) + last1 = PREV_INSN (last1); + + while (last2 != BB_HEAD (bb2) && !INSN_P (PREV_INSN (last2))) + last2 = PREV_INSN (last2); + + if (last2 != BB_HEAD (bb2) && LABEL_P (PREV_INSN (last2))) + last2 = PREV_INSN (last2); + + *f1 = last1; + *f2 = last2; + } + + return ninsns; +} + /* Return true iff the condbranches at the end of BB1 and BB2 match. */ bool condjump_equiv_p (struct equiv_info *info, bool call_init) @@ -1006,20 +1322,15 @@ condjump_equiv_p (struct equiv_info *info, bool call_init) return match; } -/* Return true iff outgoing edges of INFO->y_block and INFO->x_block match, - together with the branch instruction. This means that if we commonize the - control flow before end of the basic block, the semantic remains unchanged. - If we need to compare jumps, we set STRUCT_EQUIV_MATCH_JUMPS in *MODE, - and pass *MODE to struct_equiv_init or assign it to INFO->mode, as - appropriate. +/* Return true iff outgoing edges of BB1 and BB2 match, together with + the branch instruction. This means that if we commonize the control + flow before end of the basic block, the semantic remains unchanged. We may assume that there exists one edge with a common destination. */ static bool -outgoing_edges_match (int *mode, struct equiv_info *info) +outgoing_edges_match (int mode, basic_block bb1, basic_block bb2) { - basic_block bb1 = info->y_block; - basic_block bb2 = info->x_block; int nehedges1 = 0, nehedges2 = 0; edge fallthru1 = 0, fallthru2 = 0; edge e1, e2; @@ -1035,19 +1346,114 @@ outgoing_edges_match (int *mode, struct equiv_info *info) & (EDGE_COMPLEX | EDGE_FAKE)) == 0 && (!JUMP_P (BB_END (bb2)) || simplejump_p (BB_END (bb2)))); - *mode |= STRUCT_EQUIV_MATCH_JUMPS; /* Match conditional jumps - this may get tricky when fallthru and branch edges are crossed. */ if (EDGE_COUNT (bb1->succs) == 2 && any_condjump_p (BB_END (bb1)) && onlyjump_p (BB_END (bb1))) { + edge b1, f1, b2, f2; + bool reverse, match; + rtx set1, set2, cond1, cond2; + enum rtx_code code1, code2; + if (EDGE_COUNT (bb2->succs) != 2 || !any_condjump_p (BB_END (bb2)) || !onlyjump_p (BB_END (bb2))) return false; - info->mode = *mode; - return condjump_equiv_p (info, true); + + b1 = BRANCH_EDGE (bb1); + b2 = BRANCH_EDGE (bb2); + f1 = FALLTHRU_EDGE (bb1); + f2 = FALLTHRU_EDGE (bb2); + + /* Get around possible forwarders on fallthru edges. Other cases + should be optimized out already. */ + if (FORWARDER_BLOCK_P (f1->dest)) + f1 = single_succ_edge (f1->dest); + + if (FORWARDER_BLOCK_P (f2->dest)) + f2 = single_succ_edge (f2->dest); + + /* To simplify use of this function, return false if there are + unneeded forwarder blocks. These will get eliminated later + during cleanup_cfg. */ + if (FORWARDER_BLOCK_P (f1->dest) + || FORWARDER_BLOCK_P (f2->dest) + || FORWARDER_BLOCK_P (b1->dest) + || FORWARDER_BLOCK_P (b2->dest)) + return false; + + if (f1->dest == f2->dest && b1->dest == b2->dest) + reverse = false; + else if (f1->dest == b2->dest && b1->dest == f2->dest) + reverse = true; + else + return false; + + set1 = pc_set (BB_END (bb1)); + set2 = pc_set (BB_END (bb2)); + if ((XEXP (SET_SRC (set1), 1) == pc_rtx) + != (XEXP (SET_SRC (set2), 1) == pc_rtx)) + reverse = !reverse; + + cond1 = XEXP (SET_SRC (set1), 0); + cond2 = XEXP (SET_SRC (set2), 0); + code1 = GET_CODE (cond1); + if (reverse) + code2 = reversed_comparison_code (cond2, BB_END (bb2)); + else + code2 = GET_CODE (cond2); + + if (code2 == UNKNOWN) + return false; + + /* Verify codes and operands match. */ + match = ((code1 == code2 + && rtx_renumbered_equal_p (XEXP (cond1, 0), XEXP (cond2, 0)) + && rtx_renumbered_equal_p (XEXP (cond1, 1), XEXP (cond2, 1))) + || (code1 == swap_condition (code2) + && rtx_renumbered_equal_p (XEXP (cond1, 1), + XEXP (cond2, 0)) + && rtx_renumbered_equal_p (XEXP (cond1, 0), + XEXP (cond2, 1)))); + + /* If we return true, we will join the blocks. Which means that + we will only have one branch prediction bit to work with. Thus + we require the existing branches to have probabilities that are + roughly similar. */ + if (match + && !optimize_size + && maybe_hot_bb_p (bb1) + && maybe_hot_bb_p (bb2)) + { + int prob2; + + if (b1->dest == b2->dest) + prob2 = b2->probability; + else + /* Do not use f2 probability as f2 may be forwarded. */ + prob2 = REG_BR_PROB_BASE - b2->probability; + + /* Fail if the difference in probabilities is greater than 50%. + This rules out two well-predicted branches with opposite + outcomes. */ + if (abs (b1->probability - prob2) > REG_BR_PROB_BASE / 2) + { + if (dump_file) + fprintf (dump_file, + "Outcomes of branch in bb %i and %i differ too much (%i %i)\n", + bb1->index, bb2->index, b1->probability, prob2); + + return false; + } + } + + if (dump_file && match) + fprintf (dump_file, "Conditionals in bb %i and %i match.\n", + bb1->index, bb2->index); + + return match; } /* Generic case - we are seeing a computed jump, table jump or trapping @@ -1095,22 +1501,31 @@ outgoing_edges_match (int *mode, struct equiv_info *info) identical = false; } - if (identical - && struct_equiv_init (STRUCT_EQUIV_START | *mode, info)) + if (identical) { + replace_label_data rr; bool match; - /* Indicate that LABEL1 is to be replaced with LABEL2 + /* Temporarily replace references to LABEL1 with LABEL2 in BB1->END so that we could compare the instructions. */ - info->y_label = label1; - info->x_label = label2; + rr.r1 = label1; + rr.r2 = label2; + rr.update_label_nuses = false; + for_each_rtx (&BB_END (bb1), replace_label, &rr); - match = insns_match_p (BB_END (bb1), BB_END (bb2), info); + match = old_insns_match_p (mode, BB_END (bb1), BB_END (bb2)); if (dump_file && match) fprintf (dump_file, "Tablejumps in bb %i and %i match.\n", bb1->index, bb2->index); + /* Set the original label in BB1->END because when deleting + a block whose end is a tablejump, the tablejump referenced + from the instruction is deleted too. */ + rr.r1 = label2; + rr.r2 = label1; + for_each_rtx (&BB_END (bb1), replace_label, &rr); + return match; } } @@ -1120,8 +1535,7 @@ outgoing_edges_match (int *mode, struct equiv_info *info) /* First ensure that the instructions match. There may be many outgoing edges so this test is generally cheaper. */ - if (!struct_equiv_init (STRUCT_EQUIV_START | *mode, info) - || !insns_match_p (BB_END (bb1), BB_END (bb2), info)) + if (!old_insns_match_p (mode, BB_END (bb1), BB_END (bb2))) return false; /* Search the outgoing edges, ensure that the counts do match, find possible @@ -1187,21 +1601,22 @@ outgoing_edges_match (int *mode, struct equiv_info *info) static bool try_crossjump_to_edge (int mode, edge e1, edge e2) { - int nmatch, i; + int nmatch; basic_block src1 = e1->src, src2 = e2->src; basic_block redirect_to, redirect_from, to_remove; + rtx newpos1, newpos2; edge s; edge_iterator ei; - struct equiv_info info; - rtx x_active, y_active; + + newpos1 = newpos2 = NULL_RTX; /* If we have partitioned hot/cold basic blocks, it is a bad idea - to try this optimization. + to try this optimization. Basic block partitioning may result in some jumps that appear to - be optimizable (or blocks that appear to be mergeable), but which really - must be left untouched (they are required to make it safely across - partition boundaries). See the comments at the top of + be optimizable (or blocks that appear to be mergeable), but which really + must be left untouched (they are required to make it safely across + partition boundaries). See the comments at the top of bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */ if (flag_reorder_blocks_and_partition && no_new_pseudos) @@ -1240,66 +1655,19 @@ try_crossjump_to_edge (int mode, edge e1, edge e2) return false; /* Look for the common insn sequence, part the first ... */ - info.x_block = src2; - info.y_block = src1; - if (!outgoing_edges_match (&mode, &info)) + if (!outgoing_edges_match (mode, src1, src2)) return false; /* ... and part the second. */ - info.input_cost = optimize_size ? COSTS_N_INSNS (1) : -1; - nmatch = struct_equiv_block_eq (STRUCT_EQUIV_START | mode, &info); + nmatch = flow_find_cross_jump (mode, src1, src2, &newpos1, &newpos2); /* Don't proceed with the crossjump unless we found a sufficient number of matching instructions or the 'from' block was totally matched (such that its predecessors will hopefully be redirected and the block removed). */ - if (!nmatch) + if ((nmatch < PARAM_VALUE (PARAM_MIN_CROSSJUMP_INSNS)) + && (newpos1 != BB_HEAD (src1))) return false; - if ((nmatch -info.cur.input_count < PARAM_VALUE (PARAM_MIN_CROSSJUMP_INSNS)) - && (info.cur.y_start != BB_HEAD (src1))) - return false; - while (info.need_rerun) - { - nmatch = struct_equiv_block_eq (STRUCT_EQUIV_RERUN | mode, &info); - if (!nmatch) - return false; - if ((nmatch -info.cur.input_count < PARAM_VALUE (PARAM_MIN_CROSSJUMP_INSNS)) - && (info.cur.y_start != BB_HEAD (src1))) - return false; - } - nmatch = struct_equiv_block_eq (STRUCT_EQUIV_FINAL | mode, &info); - if ((nmatch -info.cur.input_count < PARAM_VALUE (PARAM_MIN_CROSSJUMP_INSNS)) - && (info.cur.y_start != BB_HEAD (src1))) - return false; - - /* Skip possible basic block header. */ - x_active = info.cur.x_start; - if (LABEL_P (x_active)) - x_active = NEXT_INSN (x_active); - if (NOTE_P (x_active)) - x_active = NEXT_INSN (x_active); - - y_active = info.cur.y_start; - if (LABEL_P (y_active)) - y_active = NEXT_INSN (y_active); - if (NOTE_P (y_active)) - y_active = NEXT_INSN (y_active); - - /* In order for this code to become active, either we have to be called - before reload, or struct_equiv_block_eq needs to add register scavenging - code to allocate input_reg after reload. */ - if (info.input_reg) - { - emit_insn_before (gen_move_insn (info.input_reg, info.x_input), - x_active); - emit_insn_before (gen_move_insn (info.input_reg, info.y_input), - y_active); - } - - for (i = 0; i < info.cur.local_count; i++) - if (info.local_rvalue[i]) - emit_insn_before (gen_move_insn (info.x_local[i], info.y_local[i]), - y_active); /* Here we know that the insns in the end of SRC1 which are common with SRC2 will be deleted. @@ -1335,36 +1703,30 @@ try_crossjump_to_edge (int mode, edge e1, edge e2) /* Avoid splitting if possible. We must always split when SRC2 has EH predecessor edges, or we may end up with basic blocks with both normal and EH predecessor edges. */ - if (info.cur.x_start == BB_HEAD (src2) + if (newpos2 == BB_HEAD (src2) && !(EDGE_PRED (src2, 0)->flags & EDGE_EH)) redirect_to = src2; else { - if (info.cur.x_start == BB_HEAD (src2)) + if (newpos2 == BB_HEAD (src2)) { /* Skip possible basic block header. */ - if (LABEL_P (info.cur.x_start)) - info.cur.x_start = NEXT_INSN (info.cur.x_start); - if (NOTE_P (info.cur.x_start)) - info.cur.x_start = NEXT_INSN (info.cur.x_start); + if (LABEL_P (newpos2)) + newpos2 = NEXT_INSN (newpos2); + if (NOTE_P (newpos2)) + newpos2 = NEXT_INSN (newpos2); } if (dump_file) fprintf (dump_file, "Splitting bb %i before %i insns\n", src2->index, nmatch); - redirect_to = split_block (src2, PREV_INSN (info.cur.x_start))->dest; - COPY_REG_SET (info.y_block->il.rtl->global_live_at_end, - info.x_block->il.rtl->global_live_at_end); + redirect_to = split_block (src2, PREV_INSN (newpos2))->dest; } if (dump_file) - { - fprintf (dump_file, "Cross jumping from bb %i to bb %i; %i common insns", - src1->index, src2->index, nmatch); - if (info.cur.local_count) - fprintf (dump_file, ", %i local registers", info.cur.local_count); - fprintf (dump_file, "\n"); - } + fprintf (dump_file, + "Cross jumping from bb %i to bb %i; %i common insns\n", + src1->index, src2->index, nmatch); redirect_to->count += src1->count; redirect_to->frequency += src1->frequency; @@ -1428,7 +1790,14 @@ try_crossjump_to_edge (int mode, edge e1, edge e2) /* Edit SRC1 to go to REDIRECT_TO at NEWPOS1. */ - redirect_from = split_block (src1, PREV_INSN (y_active))->src; + /* Skip possible basic block header. */ + if (LABEL_P (newpos1)) + newpos1 = NEXT_INSN (newpos1); + + if (NOTE_P (newpos1)) + newpos1 = NEXT_INSN (newpos1); + + redirect_from = split_block (src1, PREV_INSN (newpos1))->src; to_remove = single_succ (redirect_from); redirect_edge_and_branch_force (single_succ_edge (redirect_from), redirect_to);