[llvm] [InstCombine] Optimize (select %x, op(%x), 0) to op(%x) for operations where op(0) == 0 (PR #147605)

[Nikita Popov via llvm-commits]

================
@@ -0,0 +1,170 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -passes=instcombine < %s | FileCheck %s --check-prefix=FIXED-ZERO
----------------
nikic wrote:

```suggestion
; RUN: opt -S -passes=instcombine < %s | FileCheck %s
```
Do not specify prefix if you're not using multiple.

https://github.com/llvm/llvm-project/pull/147605