diff options
author | ebotcazou <ebotcazou@138bc75d-0d04-0410-961f-82ee72b054a4> | 2010-10-24 07:45:26 +0000 |
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committer | ebotcazou <ebotcazou@138bc75d-0d04-0410-961f-82ee72b054a4> | 2010-10-24 07:45:26 +0000 |
commit | dfb43842d40ed829ff958716fd8ca1d54e69ea31 (patch) | |
tree | 28e69a6ab8a84a8bba7c04bb6a5015a69b04ea57 /gcc/cfglayout.c | |
parent | 601154bb0896cbda1bdb39d9007ede48395bfee8 (diff) | |
download | gcc-dfb43842d40ed829ff958716fd8ca1d54e69ea31.tar.gz |
* cfglayout.c (fixup_reorder_chain): When ensuring that there is at
least one insn with a locus corresponding to an edge's goto_locus,
disregard non-fallthru edges to the exit block and merge the blocks
created for the same goto_locus.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@165897 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/cfglayout.c')
-rw-r--r-- | gcc/cfglayout.c | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/gcc/cfglayout.c b/gcc/cfglayout.c index 8a0d35cb619..d599b36e70a 100644 --- a/gcc/cfglayout.c +++ b/gcc/cfglayout.c @@ -940,7 +940,9 @@ fixup_reorder_chain (void) FOR_EACH_EDGE (e, ei, bb->succs) if (e->goto_locus && !(e->flags & EDGE_ABNORMAL)) { - basic_block nb; + edge e2; + edge_iterator ei2; + basic_block dest, nb; rtx end; insn = BB_END (e->src); @@ -957,10 +959,17 @@ fixup_reorder_chain (void) INSN_LOCATOR (BB_END (e->src)) = e->goto_locus; continue; } - if (e->dest != EXIT_BLOCK_PTR) + dest = e->dest; + if (dest == EXIT_BLOCK_PTR) { - insn = BB_HEAD (e->dest); - end = NEXT_INSN (BB_END (e->dest)); + /* Non-fallthru edges to the exit block cannot be split. */ + if (!(e->flags & EDGE_FALLTHRU)) + continue; + } + else + { + insn = BB_HEAD (dest); + end = NEXT_INSN (BB_END (dest)); while (insn != end && !NONDEBUG_INSN_P (insn)) insn = NEXT_INSN (insn); if (insn != end && INSN_LOCATOR (insn) @@ -972,6 +981,18 @@ fixup_reorder_chain (void) BB_END (nb) = emit_insn_after_noloc (gen_nop (), BB_END (nb), nb); INSN_LOCATOR (BB_END (nb)) = e->goto_locus; + + /* If there are other incoming edges to the destination block + with the same goto locus, redirect them to the new block as + well, this can prevent other such blocks from being created + in subsequent iterations of the loop. */ + for (ei2 = ei_start (dest->preds); (e2 = ei_safe_edge (ei2)); ) + if (e2->goto_locus + && !(e2->flags & (EDGE_ABNORMAL | EDGE_FALLTHRU)) + && locator_eq (e->goto_locus, e2->goto_locus)) + redirect_edge_and_branch (e2, nb); + else + ei_next (&ei2); } } } |