[llvm-bugs] [Bug 34959] New: Incorrect predication in SKX, opt-bisect blames SLP Vectorizer

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https://bugs.llvm.org/show_bug.cgi?id=34959

            Bug ID: 34959
           Summary: Incorrect predication in SKX, opt-bisect blames SLP
                    Vectorizer
           Product: new-bugs
           Version: trunk
          Hardware: PC
                OS: All
            Status: NEW
          Severity: enhancement
          Priority: P
         Component: new bugs
          Assignee: unassignedbugs at nondot.org
          Reporter: babokin at gmail.com
                CC: llvm-bugs at lists.llvm.org

clang trunk, rev315775, x86_64.

This may be duplication of #34665, but I failed to reduce the test to integer
types, so it seems to be different.

> cat x.cpp
#include <stdio.h>

long double a = 2;
double b = 0.0;
float c = 0.670000f;
float f = 0.0;
double d = 0.0;
double e = 0.0;
int main() {
  long double result = (a*0.5f ? (0.890000f + b ? (a ? c : 0) : 0) : 0 * d ?:
0.500000f) *
           (a*0.5f ? (0.890000f + b ? (a ? c : 0) : 0) : e * 0 ?: f);
  printf("%Lf\n", result);
}

> clang++ x.cpp -O0 -march=skx -o out; ./out
0.448900
> clang++ x.cpp -O2 -march=skx -o out; ./out
0.000000

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