[llvm] [X86] Compute `CTLZ` using fp math for `v4i32` on SSE2 targets (PR #190930)

[Simon Pilgrim via llvm-commits]

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@@ -1356,6 +1356,11 @@ X86TargetLowering::X86TargetLowering(const X86TargetMachine &TM,
     setOperationAction(ISD::STRICT_FSUB,        MVT::v2f64, Legal);
     setOperationAction(ISD::STRICT_FMUL,        MVT::v2f64, Legal);
     setOperationAction(ISD::STRICT_FDIV,        MVT::v2f64, Legal);
+
+    if (!Subtarget.hasSSSE3()) {
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RKSimon wrote:

why is the necessary?

https://github.com/llvm/llvm-project/pull/190930