| Issue |
114359
|
| Summary |
[InstCombine] increased undefinedness when folding `(or (and (bitcast F) INTMAX), INTMIN)`
|
| Labels |
new issue
|
| Assignees |
|
| Reporter |
bongjunj
|
```llvm
----------------------------------------
define float @fneg_fabs_fabs_as_int_f32_and_or.2(float %val) {
#0:
%bitcast = bitcast float %val to i32
%and = and i32 %bitcast, 2147483647
%or = or i32 %and, 2147483648
%fneg.fabs = bitcast i32 %or to float
%#1 = fmul float %fneg.fabs, %fneg.fabs
ret float %#1
}
=>
define float @fneg_fabs_fabs_as_int_f32_and_or.2(float %val) {
#0:
%#1 = fmul float %val, %val
ret float %#1
}
Transformation doesn't verify!
ERROR: Value mismatch
Example:
float %val = undef
Source:
i32 %bitcast = #x00000000 (0) [based on undef value]
i32 %and = #x00000000 (0)
i32 %or = #x80000000 (2147483648, -2147483648)
float %fneg.fabs = #x80000000 (-0.0)
float %#1 = #x00000000 (+0.0) [based on undef value]
Target:
float %#1 = #x80000000 (-0.0)
Source value: #x00000000 (+0.0)
Target value: #x80000000 (-0.0)
Summary:
0 correct transformations
1 incorrect transformations
0 failed-to-prove transformations
0 Alive2 errors
```
![]()
_______________________________________________
llvm-bugs mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-bugs
