[InstCombine] disjoint
should be dropped in foldSelectICmpEq
#121583
Open
Description
Alive2: https://alive2.llvm.org/ce/z/am7W57
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define i32 @src(i32 noundef %x, i32 noundef %y, i32 %c) {
entry:
%xor = xor i32 noundef %y, noundef %x
%cmp = icmp eq i32 %xor, %c
%and = and i32 noundef %x, noundef %y
%or = or disjoint i32 noundef %y, noundef %x
%not = xor i32 %c, 4294967295
%and1 = and i32 %or, %not
%cond = select i1 %cmp, i32 %and, i32 %and1
ret i32 %cond
}
=>
define i32 @src(i32 noundef %x, i32 noundef %y, i32 %c) {
entry:
%or = or disjoint i32 noundef %y, noundef %x
%not = xor i32 %c, 4294967295
%and1 = and i32 %or, %not
ret i32 %and1
}
Transformation doesn't verify!
ERROR: Target is more poisonous than source
Example:
i32 noundef %x = #x0000000f (15)
i32 noundef %y = #x0000000f (15)
i32 %c = #x00000000 (0)
Source:
i32 %xor = #x00000000 (0)
i1 %cmp = #x1 (1)
i32 %and = #x0000000f (15)
i32 %or = poison
i32 %not = #xffffffff (4294967295, -1)
i32 %and1 = poison
i32 %cond = #x0000000f (15)
Target:
i32 %or = poison
i32 %not = #xffffffff (4294967295, -1)
i32 %and1 = poison
Source value: #x0000000f (15)
Target value: poison
Summary:
0 correct transformations
1 incorrect transformations
0 failed-to-prove transformations
0 Alive2 errors