[llvm] [X86] Use BMM for bitreverse without GFNI (PR #209223)

[Simon Pilgrim via llvm-commits]

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@@ -1364,7 +1364,8 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
     setOperationAction(ISD::STRICT_FDIV,        MVT::v2f64, Legal);
   }
 
-  if (!Subtarget.useSoftFloat() && Subtarget.hasGFNI()) {
+  if (!Subtarget.useSoftFloat() &&
+      (Subtarget.hasGFNI() || Subtarget.hasBMM())) {
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RKSimon wrote:

this is incorrect as its affecting the entire GFNI block below - better to duplicate the setOperationAction(ISD::BITREVERSE lines further down in the existing Subtarget.hasBMM() block.

https://github.com/llvm/llvm-project/pull/209223