[llvm] [X86] Added ComputeKnownBits support for BEXTR (PR #199558)

[Simon Pilgrim via llvm-commits]

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@@ -2780,6 +2780,57 @@ TEST_F(ComputeKnownBitsTest, ComputeKnownUSubSatZerosPreserved) {
   expectKnownBits(/*zero*/ 2u, /*one*/ 0u);
 }
 
+TEST_F(ComputeKnownBitsTest, ComputeKnownBitsX86BmiBextr32) {
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RKSimon wrote:

don't bother with unit tests - the IR tests are better

https://github.com/llvm/llvm-project/pull/199558