| Issue |
167178
|
| Summary |
Missed Optimization: simplify ((x lshr 9) + x) < 256 to x < 256
|
| Labels |
new issue
|
| Assignees |
|
| Reporter |
Leo0506
|
```
define i1 @src(i32 %arg0) {
%v0 = lshr i32 %arg0, 9
%v1 = add nuw i32 %v0, %arg0
%v2 = icmp ult i32 %v1, 256
ret i1 %v2
}
define i1 @tgt(i32 %arg0) {
%v2 = icmp ult i32 %arg0, 256
ret i1 %v2
}
```
alive2: https://alive2.llvm.org/ce/z/Ab_dJk
godbolt: https://godbolt.org/z/nYo8114Wq
Pattern found in: https://github.com/dtcxzyw/llvm-opt-benchmark/blob/main/bench/ffmpeg/optimized/webp.ll
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