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| author | Eric Botcazou <ebotcazou@adacore.com> | 2010-10-24 07:45:26 +0000 |
|---|---|---|
| committer | Eric Botcazou <ebotcazou@gcc.gnu.org> | 2010-10-24 07:45:26 +0000 |
| commit | 4cce988e5b77892135180d6f1a486cfc3e1d5bac (patch) | |
| tree | 28e69a6ab8a84a8bba7c04bb6a5015a69b04ea57 /gcc | |
| parent | be8cf3b55e32b8bd1eb0672d90f91fc246586178 (diff) | |
| download | gcc-4cce988e5b77892135180d6f1a486cfc3e1d5bac.zip gcc-4cce988e5b77892135180d6f1a486cfc3e1d5bac.tar.gz gcc-4cce988e5b77892135180d6f1a486cfc3e1d5bac.tar.bz2 | |
cfglayout.c (fixup_reorder_chain): When ensuring that there is at least one insn with a locus corresponding to an...
* 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.
From-SVN: r165897
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/cfglayout.c | 29 |
2 files changed, 32 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 809f3be..189f349 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2010-10-24 Eric Botcazou <ebotcazou@adacore.com> + + * 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. + 2010-10-23 Joseph Myers <joseph@codesourcery.com> * gcc.c (n_switches_alloc_debug_check): New. diff --git a/gcc/cfglayout.c b/gcc/cfglayout.c index 8a0d35c..d599b36 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); } } } |