[Bug tree-optimization/68862] New: [6 Regression] g++.dg/torture/pr59163.C FAILs with -flive-range-shrinkage

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68862

            Bug ID: 68862
           Summary: [6 Regression] g++.dg/torture/pr59163.C FAILs with
                    -flive-range-shrinkage
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu
            Target: x86_64-pc-linux-gnu

Compiler output:
$ gcc testcase.c -O3 -flive-range-shrinkage
$ ./a.out 
Segmentation fault

(gdb) disassemble 
Dump of assembler code for function foo:
   0x0000000000400540 <+0>:     movaps 0x89(%rip),%xmm0        # 0x4005d0
=> 0x0000000000400547 <+7>:     mulps  (%rdi),%xmm0
   0x000000000040054a <+10>:    movups %xmm0,(%rdi)
   0x000000000040054d <+13>:    retq   
End of assembler dump.

(gdb) p/x $rdi
$2 = 0x7fffffffd7e4

There is an unaligned access.

Tested revisions:
trunk r231533 - FAIL
5-branch r231528 - OK
4_9-branch r231529 - OK