http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58685

Mikael Pettersson <mikpelinux at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bernds at gcc dot gnu.org,
                   |                            |mikpelinux at gmail dot com

--- Comment #1 from Mikael Pettersson <mikpelinux at gmail dot com> ---
Started with r179553, -fshrink-wrap introduction and enabling on x86.  Adding
-fno-shrink-wrap avoids the bug.  Author CC:d.

The code generation differences on this test case at this revision show no
control flow changes but some register save/restore changes:

--- pr58685.s-r179552   2013-10-11 12:46:05.717857352 +0200
+++ pr58685.s-r179553   2013-10-11 12:49:52.847494641 +0200
@@ -45,13 +45,11 @@
 fn3:
 .LFB2:
        .cfi_startproc
-       pushq   %r8
-       .cfi_def_cfa_offset 16
        movl    $0, b(%rip)
        jmp     .L7
 .L9:
-       movl    $0, e(%rip)
        cmpl    $0, (%rdi)
+       movl    $0, e(%rip)
        jne     .L8
        movl    $1, e(%rip)
 .L8:
@@ -61,6 +59,8 @@
        movl    b(%rip), %eax
        testl   %eax, %eax
        jns     .L9
+       pushq   %rdi
+       .cfi_def_cfa_offset 16
        xorl    %eax, %eax
        call    fn1
        cmpl    $0, c(%rip)
@@ -81,7 +81,7 @@
 main:
 .LFB3:
        .cfi_startproc
-       pushq   %r10
+       pushq   %r9
        .cfi_def_cfa_offset 16
        movq    g(%rip), %rdi
        call    fn3
@@ -94,7 +94,7 @@
        call    __assert_fail
 .L12:
        xorl    %eax, %eax
-       popq    %r9
+       popq    %r8
        .cfi_def_cfa_offset 8
        ret
        .cfi_endproc

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