[clang] [Clang] Honor '#pragma STDC FENV_ROUND' in __builtin_store_half/halff (PR #173821)

[Wenju He via cfe-commits]

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@@ -0,0 +1,21 @@
+// RUN: %clang_cc1 %s -cl-std=cl3.0 -emit-llvm -o - -triple x86_64-unknown-unknown | FileCheck %s
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wenju-he wrote:

> Needs REQUIRES: x86-registered-target?

The test can pass when X86 is not in LLVM_TARGETS_TO_BUILD. Only frontend compilation is triggered here.

https://github.com/llvm/llvm-project/pull/173821