Refactor the newly created <bit> header. Still (almost) NFC. Reviewed as https://reviews.llvm.org/D50876
llvm-svn: 340049
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: ecb7f4da68ec8bc6b261f2338d79d167101cdc79
diff --git a/include/bit b/include/bit
index 2d403bf..5bf5214 100644
--- a/include/bit
+++ b/include/bit
@@ -35,135 +35,123 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+#ifndef _LIBCPP_COMPILER_MSVC
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __ctz(unsigned __x) { return __builtin_ctz(__x); }
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __ctz(unsigned long __x) { return __builtin_ctzl(__x); }
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __ctz(unsigned long long __x) { return __builtin_ctzll(__x); }
+
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __clz(unsigned __x) { return __builtin_clz(__x); }
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __clz(unsigned long __x) { return __builtin_clzl(__x); }
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __clz(unsigned long long __x) { return __builtin_clzll(__x); }
+
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __popcount(unsigned __x) { return __builtin_popcount(__x); }
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __popcount(unsigned long __x) { return __builtin_popcountl(__x); }
+
+inline _LIBCPP_INLINE_VISIBILITY
+int __popcount(unsigned long long __x) { return __builtin_popcountll(__x); }
+
+#else // _LIBCPP_COMPILER_MSVC
+
// Precondition: __x != 0
inline _LIBCPP_INLINE_VISIBILITY
-unsigned __ctz(unsigned __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return static_cast<unsigned>(__builtin_ctz(__x));
-#else
+int __ctz(unsigned __x) {
static_assert(sizeof(unsigned) == sizeof(unsigned long), "");
static_assert(sizeof(unsigned long) == 4, "");
- unsigned long where;
- // Search from LSB to MSB for first set bit.
- // Returns zero if no set bit is found.
- if (_BitScanForward(&where, __x))
- return where;
+ unsigned long __where;
+ if (_BitScanForward(&__where, __x))
+ return static_cast<int>(__where);
return 32;
-#endif
}
inline _LIBCPP_INLINE_VISIBILITY
-unsigned long __ctz(unsigned long __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return static_cast<unsigned long>(__builtin_ctzl(__x));
-#else
+int __ctz(unsigned long __x) {
static_assert(sizeof(unsigned long) == sizeof(unsigned), "");
return __ctz(static_cast<unsigned>(__x));
-#endif
}
inline _LIBCPP_INLINE_VISIBILITY
-unsigned long long __ctz(unsigned long long __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return static_cast<unsigned long long>(__builtin_ctzll(__x));
-#else
- unsigned long where;
-// Search from LSB to MSB for first set bit.
-// Returns zero if no set bit is found.
+int __ctz(unsigned long long __x) {
+ unsigned long __where;
#if defined(_LIBCPP_HAS_BITSCAN64)
(defined(_M_AMD64) || defined(__x86_64__))
- if (_BitScanForward64(&where, __x))
- return static_cast<int>(where);
+ if (_BitScanForward64(&__where, __x))
+ return static_cast<int>(__where);
#else
// Win32 doesn't have _BitScanForward64 so emulate it with two 32 bit calls.
- // Scan the Low Word.
- if (_BitScanForward(&where, static_cast<unsigned long>(__x)))
- return where;
- // Scan the High Word.
- if (_BitScanForward(&where, static_cast<unsigned long>(__x >> 32)))
- return where + 32; // Create a bit offset from the LSB.
+ if (_BitScanForward(&__where, static_cast<unsigned long>(__x)))
+ return static_cast<int>(__where);
+ if (_BitScanForward(&__where, static_cast<unsigned long>(__x >> 32)))
+ return static_cast<int>(__where + 32);
#endif
return 64;
-#endif // _LIBCPP_COMPILER_MSVC
}
// Precondition: __x != 0
inline _LIBCPP_INLINE_VISIBILITY
-unsigned __clz(unsigned __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return static_cast<unsigned>(__builtin_clz(__x));
-#else
+int __clz(unsigned __x) {
static_assert(sizeof(unsigned) == sizeof(unsigned long), "");
static_assert(sizeof(unsigned long) == 4, "");
- unsigned long where;
- // Search from LSB to MSB for first set bit.
- // Returns zero if no set bit is found.
- if (_BitScanReverse(&where, __x))
- return 31 - where;
+ unsigned long __where;
+ if (_BitScanReverse(&__where, __x))
+ return static_cast<int>(31 - __where);
return 32; // Undefined Behavior.
-#endif
}
inline _LIBCPP_INLINE_VISIBILITY
-unsigned long __clz(unsigned long __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return static_cast<unsigned long>(__builtin_clzl (__x));
-#else
+int __clz(unsigned long __x) {
static_assert(sizeof(unsigned) == sizeof(unsigned long), "");
return __clz(static_cast<unsigned>(__x));
-#endif
}
inline _LIBCPP_INLINE_VISIBILITY
-unsigned long long __clz(unsigned long long __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return static_cast<unsigned long long>(__builtin_clzll(__x));
-#else
- unsigned long where;
-// BitScanReverse scans from MSB to LSB for first set bit.
-// Returns 0 if no set bit is found.
+int __clz(unsigned long long __x) {
+ unsigned long __where;
#if defined(_LIBCPP_HAS_BITSCAN64)
- if (_BitScanReverse64(&where, __x))
- return static_cast<int>(63 - where);
+ if (_BitScanReverse64(&__where, __x))
+ return static_cast<int>(63 - __where);
#else
- // Scan the high 32 bits.
- if (_BitScanReverse(&where, static_cast<unsigned long>(__x >> 32)))
- return 63 - (where + 32); // Create a bit offset from the MSB.
- // Scan the low 32 bits.
- if (_BitScanReverse(&where, static_cast<unsigned long>(__x)))
- return 63 - where;
+ // Win32 doesn't have _BitScanReverse64 so emulate it with two 32 bit calls.
+ if (_BitScanReverse(&__where, static_cast<unsigned long>(__x >> 32)))
+ return static_cast<int>(63 - (__where + 32));
+ if (_BitScanReverse(&__where, static_cast<unsigned long>(__x)))
+ return static_cast<int>(63 - __where);
#endif
return 64; // Undefined Behavior.
-#endif // _LIBCPP_COMPILER_MSVC
}
-inline _LIBCPP_INLINE_VISIBILITY int __pop_count(unsigned __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return __builtin_popcount (__x);
-#else
+inline _LIBCPP_INLINE_VISIBILITY int __popcount(unsigned __x) {
static_assert(sizeof(unsigned) == 4, "");
return __popcnt(__x);
-#endif
}
-inline _LIBCPP_INLINE_VISIBILITY int __pop_count(unsigned long __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return __builtin_popcountl (__x);
-#else
+inline _LIBCPP_INLINE_VISIBILITY int __popcount(unsigned long __x) {
static_assert(sizeof(unsigned long) == 4, "");
return __popcnt(__x);
-#endif
}
-inline _LIBCPP_INLINE_VISIBILITY int __pop_count(unsigned long long __x) {
-#ifndef _LIBCPP_COMPILER_MSVC
- return __builtin_popcountll(__x);
-#else
+inline _LIBCPP_INLINE_VISIBILITY int __popcount(unsigned long long __x) {
static_assert(sizeof(unsigned long long) == 8, "");
return __popcnt64(__x);
-#endif
}
+#endif // _LIBCPP_COMPILER_MSVC
+
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP_BIT