[libclc] Move fp16 pragma guards out of header file

Having the fp16 pragmas enabled in the header file is risky, as we have
some headers that also disable pragmas. We want to be as immune to
changes in the order of included header files as possible.

This pattern of setting pragmas in the implementation files is also far
more common across the codebase.

Author: frasercrmck

libclc/clc/include/clc/clcmacro.h

@@ -207,10 +207,6 @@
     return BUILTIN(x);                                                         \
   }
 
-#ifdef cl_khr_fp16
-
-#pragma OPENCL EXTENSION cl_khr_fp16 : enable
-
 #define _CLC_DEFINE_UNARY_BUILTIN_FP16(FUNCTION)                               \
   _CLC_DEF _CLC_OVERLOAD half FUNCTION(half x) {                               \
     return (half)FUNCTION((float)x);                                           \
@@ -223,11 +219,4 @@
   }                                                                            \
   _CLC_BINARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, half, FUNCTION, half, half)
 
-#else
-
-#define _CLC_DEFINE_UNARY_BUILTIN_FP16(FUNCTION)
-#define _CLC_DEFINE_BINARY_BUILTIN_FP16(FUNCTION)
-
-#endif
-
 #endif // __CLC_CLCMACRO_H__

libclc/generic/lib/math/acos.cl

@@ -172,4 +172,10 @@ _CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, acos, double);
 
 #endif // cl_khr_fp64
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
 _CLC_DEFINE_UNARY_BUILTIN_FP16(acos)
+
+#endif

libclc/generic/lib/math/acosh.cl

@@ -126,4 +126,10 @@ _CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, acosh, double)
 
 #endif
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
 _CLC_DEFINE_UNARY_BUILTIN_FP16(acosh)
+
+#endif

libclc/generic/lib/math/acospi.cl

@@ -171,4 +171,10 @@ _CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, acospi, double)
 
 #endif
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
 _CLC_DEFINE_UNARY_BUILTIN_FP16(acospi)
+
+#endif

libclc/generic/lib/math/asinh.cl

@@ -292,4 +292,10 @@ _CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, asinh, double)
 
 #endif
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
 _CLC_DEFINE_UNARY_BUILTIN_FP16(asinh)
+
+#endif

libclc/generic/lib/math/atan.cl

@@ -182,5 +182,10 @@ _CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, atan, double);
 
 #endif // cl_khr_fp64
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
 
 _CLC_DEFINE_UNARY_BUILTIN_FP16(atan)
+
+#endif

libclc/generic/lib/math/atan2.cl

@@ -236,4 +236,10 @@ _CLC_BINARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, atan2, double, double);
 
 #endif
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
 _CLC_DEFINE_BINARY_BUILTIN_FP16(atan2)
+
+#endif

libclc/generic/lib/math/atan2pi.cl

@@ -220,4 +220,10 @@ _CLC_BINARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, atan2pi, double, double)
 
 #endif
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
 _CLC_DEFINE_BINARY_BUILTIN_FP16(atan2pi)
+
+#endif

libclc/generic/lib/math/atanh.cl

@@ -112,4 +112,10 @@ _CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, atanh, double)
 
 #endif
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
 _CLC_DEFINE_UNARY_BUILTIN_FP16(atanh)
+
+#endif

libclc/generic/lib/math/atanpi.cl

@@ -181,4 +181,10 @@ _CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, double, atanpi, double)
 
 #endif
 
+#ifdef cl_khr_fp16
+
+#pragma OPENCL EXTENSION cl_khr_fp16 : enable
+
 _CLC_DEFINE_UNARY_BUILTIN_FP16(atanpi)
+
+#endif