------- Comment #6 from hutchinsonandy at gcc dot gnu dot org 2009-09-27 17:30
-------
Created an attachment (id=18663)
--> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=18663&action=view)
Patch to cfgrtl.c commit_one_edge_insertion()
The problem is in cfgrtl.c function commit_one_edge_insertion()
It does copy value for phi nodes to previous edge. If it find jump on edge it
places copy before it. It assumes that edge is fall thru edge.
For a fall thru edge, the last instruction can be anything - specifically a
jump just created by RTL expander.
The bug has been present since Rev 146817
I have attached patch that correct the problem.
Index: cfgrtl.c
===================================================================
--- cfgrtl.c (revision 152217)
+++ cfgrtl.c (working copy)
@@ -1482,8 +1482,9 @@
happens on the fr30 for example.
We know this block has a single successor, so we can just emit
- the queued insns before the jump. */
- if (JUMP_P (BB_END (bb)))
+ the queued insns before the jump. Fallthru edges can have
+ jumps created by RTL expander, so ignore these. */
+ if (!(e->flags & EDGE_FALLTHRU) && JUMP_P (BB_END (bb)))
before = BB_END (bb);
else
{
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41440
