[llvm] Implement SPV_KHR_poison_freeze extension (PR #198037)

[Marcos Maronas via llvm-commits]

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@@ -5,12 +5,22 @@
 ; entry points when SPV_KHR_poison_freeze is enabled and poison present in the
 ; module.
 
-; CHECK-DAG: OpCapability PoisonFreezeKHR
-; CHECK-DAG: OpExtension "SPV_KHR_poison_freeze"
-; CHECK:     OpEntryPoint Kernel %[[#ENTRY:]] "kernel_with_poison"
-; CHECK-DAG: OpExecutionMode %[[#ENTRY]] ArithmeticPoisonKHR
+; CHECK-DAG:     OpCapability PoisonFreezeKHR
+; CHECK-DAG:     OpExtension "SPV_KHR_poison_freeze"
+; CHECK-COUNT-2: OpExecutionMode %[[#]] ArithmeticPoisonKHR
+; CHECK-NOT:     OpExecutionMode %[[#]] ArithmeticPoisonKHR
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maarquitos14 wrote:

This is for `entry_b`, right?

https://github.com/llvm/llvm-project/pull/198037