[libclc] [libclc] Move several integer functions to CLC library (PR #116786)

[Fraser Cormack via cfe-commits]

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@@ -0,0 +1,44 @@
+#include <clc/clcmacro.h>
+#include <clc/integer/clc_clz.h>
+#include <clc/internal/clc.h>
+
+_CLC_OVERLOAD _CLC_DEF char __clc_clz(char x) {
+  return __clc_clz((ushort)(uchar)x) - 8;
+}
+
+_CLC_OVERLOAD _CLC_DEF uchar __clc_clz(uchar x) {
+  return __clc_clz((ushort)x) - 8;
+}
+
+_CLC_OVERLOAD _CLC_DEF short __clc_clz(short x) {
+  return x ? __builtin_clzs(x) : 16;
+}
+
+_CLC_OVERLOAD _CLC_DEF ushort __clc_clz(ushort x) {
+  return x ? __builtin_clzs(x) : 16;
+}
+
+_CLC_OVERLOAD _CLC_DEF int __clc_clz(int x) {
+  return x ? __builtin_clz(x) : 32;
+}
+
+_CLC_OVERLOAD _CLC_DEF uint __clc_clz(uint x) {
+  return x ? __builtin_clz(x) : 32;
+}
+
+_CLC_OVERLOAD _CLC_DEF long __clc_clz(long x) {
+  return x ? __builtin_clzl(x) : 64;
+}
+
+_CLC_OVERLOAD _CLC_DEF ulong __clc_clz(ulong x) {
+  return x ? __builtin_clzl(x) : 64;
+}
+
+_CLC_UNARY_VECTORIZE(_CLC_OVERLOAD _CLC_DEF, char, __clc_clz, char)
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frasercrmck wrote:

It would be nice if `__builtin_clz*` builtins could operate on vector types. I'll make a note of this improvement.

https://github.com/llvm/llvm-project/pull/116786