[llvm] [LegalizeDAG] Optimize CodeGen for `ISD::CTLZ_ZERO_UNDEF` (PR #83039)

[Manish Kausik H via llvm-commits]

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@@ -23,79 +23,84 @@ define void @f() nounwind {
 ; X86-NEXT:    pushl %esi
 ; X86-NEXT:    andl $-16, %esp
 ; X86-NEXT:    subl $176, %esp
-; X86-NEXT:    movzbl {{[0-9]+}}(%esp), %edx
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Nirhar wrote:

@RKSimon @arsenm My PR somehow modifies the assembly generated in this test(which I think is not supposed to happen, given that this test has no calls to cltz intrinsic). Any heads up on why this could happen?

https://github.com/llvm/llvm-project/pull/83039