[libclc] [libclc] Refine __clc_fp*_subnormals_supported and __clc_flush_denormal_if_not_supported (PR #157633)

[Wenju He via cfe-commits]

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@@ -127,9 +127,9 @@ _CLC_DEF _CLC_OVERLOAD float __clc_sw_fma(float a, float b, float c) {
     return c;
   }
 
-  a = __clc_flush_denormal_if_not_supported(a);
-  b = __clc_flush_denormal_if_not_supported(b);
-  c = __clc_flush_denormal_if_not_supported(c);
+  a = __clc_soft_flush_denormal(a);
+  b = __clc_soft_flush_denormal(b);
+  c = __clc_soft_flush_denormal(c);
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wenju-he wrote:

SPIR-V don't need __clc_sw_fma anymore if SPV_KHR_fma extension is enabled. The extension is already implemented in llvm-spirv and soon will be implemented in llvm SPIR-V backend: https://github.com/llvm/llvm-project/pull/173057

https://github.com/llvm/llvm-project/pull/157633