[Bug tree-optimization/59644] [4.9 Regression] r206243 miscompiles Linux kernel

[trippels at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59644

Markus Trippelsdorf <trippels at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|target                      |tree-optimization

--- Comment #16 from Markus Trippelsdorf <trippels at gcc dot gnu.org> ---
Ok it's the second hunk that causes the hang:

@@ -2680,28 +2677,25 @@
 printk:
        pushq   %rbp
        movq    %rsp, %rbp
-       pushq   %r10
-       leaq    -56(%rbp), %rax
-       leaq    16(%rbp), %r10
        subq    $72, %rsp
+       leaq    16(%rbp), %r10
        movq    %rsi, -48(%rbp)
        movq    %rdx, -40(%rbp)
        movq    %rcx, -32(%rbp)
        movq    %r8, -24(%rbp)
-       xorl    %ecx, %ecx
+       leaq    -56(%rbp), %rax
        movq    %r9, -16(%rbp)
        movq    %rdi, %r8
        leaq    -80(%rbp), %r9
+       xorl    %ecx, %ecx
        xorl    %edx, %edx
        orl     $-1, %esi
        xorl    %edi, %edi
-       movq    %r10, -72(%rbp)
        movl    $8, -80(%rbp)
+       movq    %r10, -72(%rbp)
        movq    %rax, -64(%rbp)
        call    vprintk_emit
-       addq    $72, %rsp
-       popq    %r10
-       popq    %rbp
+       leave
        ret
        .size   printk, .-printk
 .LCOLDE47: