[clang] [X86] Allow using the lzcnt intrinsics for non-LZCNT targets (PR #128284)

[Simon Pilgrim via cfe-commits]

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@@ -1,5 +1,5 @@
-// RUN: %clang_cc1 -x c -ffreestanding %s -triple=x86_64-apple-darwin -target-feature +lzcnt -emit-llvm -o - | FileCheck %s
-// RUN: %clang_cc1 -x c++ -std=c++11 -ffreestanding %s -triple=x86_64-apple-darwin -target-feature +lzcnt -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 -x c -ffreestanding %s -triple=x86_64-apple-darwin -emit-llvm -o - | FileCheck %s
+// RUN: %clang_cc1 -x c++ -std=c++11 -ffreestanding %s -triple=x86_64-apple-darwin -emit-llvm -o - | FileCheck %s
 
 
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RKSimon wrote:

Add a comment explaining that these will lower correctly with/without lzcnt

https://github.com/llvm/llvm-project/pull/128284