| Issue |
153999
|
| Summary |
Missed optimization: eliminate redundant null pointer check
|
| Labels |
new issue
|
| Assignees |
|
| Reporter |
zxt5
|
```
define i1 @src(ptr %arg0) {
%v0 = getelementptr inbounds nuw i8, ptr %arg0, i64 24
%v1 = load i32, ptr %v0, align 8
%v2 = icmp eq i32 %v1, 14
%v3 = icmp ne ptr %arg0, null
%v4 = and i1 %v3, %v2
ret i1 %v4
}
define i1 @tgt(ptr %arg0) {
%v0 = getelementptr inbounds nuw i8, ptr %arg0, i64 24
%v1 = load i32, ptr %v0, align 8
%v2 = icmp eq i32 %v1, 14
ret i1 %v2
}
```
Alive2: https://alive2.llvm.org/ce/z/-wS56j
Godbolt: https://godbolt.org/z/sbnj71bqa
Found the pattern in https://github.com/dtcxzyw/llvm-opt-benchmark/blob/main/bench/llvm/optimized/DAGISelMatcher.ll
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