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-rw-r--r--absl/random/internal/fastmath.h23
1 files changed, 3 insertions, 20 deletions
diff --git a/absl/random/internal/fastmath.h b/absl/random/internal/fastmath.h
index 6baeb5a7..963b7690 100644
--- a/absl/random/internal/fastmath.h
+++ b/absl/random/internal/fastmath.h
@@ -22,27 +22,22 @@
#include <cmath>
#include <cstdint>
-#include "absl/base/internal/bits.h"
+#include "absl/numeric/bits.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
namespace random_internal {
-// Returns the position of the first bit set.
-inline int LeadingSetBit(uint64_t n) {
- return 64 - base_internal::CountLeadingZeros64(n);
-}
-
// Compute log2(n) using integer operations.
// While std::log2 is more accurate than std::log(n) / std::log(2), for
// very large numbers--those close to std::numeric_limits<uint64_t>::max() - 2,
// for instance--std::log2 rounds up rather than down, which introduces
// definite skew in the results.
inline int IntLog2Floor(uint64_t n) {
- return (n <= 1) ? 0 : (63 - base_internal::CountLeadingZeros64(n));
+ return (n <= 1) ? 0 : (63 - countl_zero(n));
}
inline int IntLog2Ceil(uint64_t n) {
- return (n <= 1) ? 0 : (64 - base_internal::CountLeadingZeros64(n - 1));
+ return (n <= 1) ? 0 : (64 - countl_zero(n - 1));
}
inline double StirlingLogFactorial(double n) {
@@ -55,18 +50,6 @@ inline double StirlingLogFactorial(double n) {
(1.0 / 360.0) * ninv * ninv * ninv;
}
-// Rotate value right.
-//
-// We only implement the uint32_t / uint64_t versions because
-// 1) those are the only ones we use, and
-// 2) those are the only ones where clang detects the rotate idiom correctly.
-inline constexpr uint32_t rotr(uint32_t value, uint8_t bits) {
- return (value >> (bits & 31)) | (value << ((-bits) & 31));
-}
-inline constexpr uint64_t rotr(uint64_t value, uint8_t bits) {
- return (value >> (bits & 63)) | (value << ((-bits) & 63));
-}
-
} // namespace random_internal
ABSL_NAMESPACE_END
} // namespace absl