[llvm] [ValueTracking][X86] Compute KnownBits for phadd/phsub (PR #92429)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,254 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -S -passes=instcombine < %s | FileCheck %s
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RKSimon wrote:

Maybe rename this file to knownbits-x86-hadd-hsub.ll to make it clear these are target specific

https://github.com/llvm/llvm-project/pull/92429