[Bug tree-optimization/119875] New: loop with floating point conditional move not vectorized without -ffast-math

[hubicka at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119875

            Bug ID: 119875
           Summary: loop with floating point conditional move not
                    vectorized without -ffast-math
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hubicka at gcc dot gnu.org
  Target Milestone: ---

double a[1000];
double b[1000];
double c[1000];
double d[1000];
void test()
{
        for (int i = 0; i < 1000; i++)
                a[i] = b[i] > 0 ? c[i] + 1 : c[i] + 2;
}

is vectorized only with -ffast-math, while clang does it w/o:

.LBB0_1:                                # =>This Inner Loop Header: Depth=1
        xorpd   %xmm2, %xmm2
        cmpltpd -16(%rcx,%rax,8), %xmm2
        xorpd   %xmm3, %xmm3
        cmpltpd (%rcx,%rax,8), %xmm3
        movapd  %xmm1, %xmm4
        andpd   %xmm2, %xmm4
        andnpd  %xmm0, %xmm2
        orpd    %xmm4, %xmm2
        movapd  %xmm1, %xmm4
        andpd   %xmm3, %xmm4
        andnpd  %xmm0, %xmm3
        orpd    %xmm4, %xmm3
        addpd   -16(%rdx,%rax,8), %xmm2
        addpd   (%rdx,%rax,8), %xmm3
        movapd  %xmm2, -16(%rsi,%rax,8)
        movapd  %xmm3, (%rsi,%rax,8)
        addq    $4, %rax