[libclc] [libclc] Move sqrt to CLC library (PR #128748)

[Matt Arsenault via cfe-commits]

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@@ -21,19 +21,17 @@
  */
 
 #if __CLC_FPSIZE == 64
-#define __CLC_NAN __builtin_nan("")
-#define ZERO 0.0
+#define __CLC_NAN DBL_NAN
 #elif __CLC_FPSIZE == 32
-#define __CLC_NAN NAN
-#define ZERO 0.0f
+#define __CLC_NAN FLT_NAN
 #elif __CLC_FPSIZE == 16
-#define __CLC_NAN (half)NAN
-#define ZERO 0.0h
+#define __CLC_NAN HALF_NAN
 #endif
 
-_CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE __clc_sqrt(__CLC_GENTYPE val) {
-  return val < ZERO ? __CLC_NAN : __clc_llvm_intr_sqrt(val);
+__attribute__((weak)) _CLC_OVERLOAD _CLC_DEF __CLC_GENTYPE
+__clc_sqrt(__CLC_GENTYPE val) {
+  return val < __CLC_FP_LIT(0.0) ? (__CLC_GENTYPE)__CLC_NAN
+                                 : __builtin_elementwise_sqrt(val);
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arsenm wrote:

This pre-filtering of the argument is unnecessary. Many years ago the sqrt intrinsic officially did not handle the nan cases, but that has been fixed. This can be the raw builtin call 

https://github.com/llvm/llvm-project/pull/128748