Wrong select (fcmp ...) (fadd ...) folding to llvm max intrinsic #139041
Description
define float @test_fcmp_ogt_fadd_select_rewrite_and_fastmath.2(float %in) {
%cmp1 = fcmp nnan ogt float %in, 0.000000e+00
%2 = fadd float %in, 1.000000e+00
%sel = select fast i1 %cmp1, float %2, float 1.000000e+00
ret float %sel
}define float @test_fcmp_ogt_fadd_select_rewrite_and_fastmath(float %in) {
#0:
%cmp1 = fcmp nnan ogt float %in, 0.000000
%add = fadd float %in, 1.000000
%sel = select fast i1 %cmp1, float %add, float 1.000000
ret float %sel
}
=>
define float @test_fcmp_ogt_fadd_select_rewrite_and_fastmath(float %in) {
#0:
%sel = fmax nnan ninf nsz float %in, 0.000000
%add = fadd nnan ninf nsz float %sel, 1.000000
ret float %add
}
Transformation doesn't verify!
ERROR: Target is more poisonous than source
Example:
float %in = #xff800000 (-oo)
Source:
i1 %cmp1 = #x0 (0)
float %add = #xff800000 (-oo)
float %sel = #x00000000 (+0.0)
Target:
float %sel = poison
float %add = poison
Source value: #x00000000 (+0.0)
Target value: poison
Summary:
0 correct transformations
1 incorrect transformations
0 failed-to-prove transformations
0 Alive2 errors
While the alive2 site (https://alive2.llvm.org/ce/z/50KuQH) complains that it used approximation so it could not conclude,
I think it may have nothing to do with approximation.
Targeted Commit of Test: a0c4876
In addition, the alive2 proof in the commit message is also failing: https://alive2.llvm.org/ce/z/tVrvYo