http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60520
--- Comment #4 from H.J. Lu <hjl.tools at gmail dot com> ---
This change:
diff --git a/gcc/function.c b/gcc/function.c
index a61e475..3b6718f 100644
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -6238,6 +6238,7 @@ thread_prologue_and_epilogue_insns (void)
}
/* Now duplicate the tails. */
if (!bitmap_empty_p (&bb_tail))
+ {
FOR_EACH_BB_REVERSE_FN (bb, cfun)
{
basic_block copy_bb, tbb;
@@ -6304,6 +6305,17 @@ thread_prologue_and_epilogue_insns (void)
if (bitmap_empty_p (&bb_tail))
break;
}
+
+ /* Basic blocks may have been changed. Merge each basic block
+ with its successor if possible. */
+ FOR_EACH_BB_FN (bb, cfun)
+ if (single_succ_p (bb))
+ {
+ basic_block succ_bb = single_succ (bb);
+ if (can_merge_blocks_p (bb, succ_bb))
+ merge_blocks (bb, succ_bb);
+ }
+ }
}
fail_shrinkwrap:
seems to work.
