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-rw-r--r--abseil-cpp/absl/random/internal/pcg_engine.h32
1 files changed, 6 insertions, 26 deletions
diff --git a/abseil-cpp/absl/random/internal/pcg_engine.h b/abseil-cpp/absl/random/internal/pcg_engine.h
index 53c23fe..e1f4ef3 100644
--- a/abseil-cpp/absl/random/internal/pcg_engine.h
+++ b/abseil-cpp/absl/random/internal/pcg_engine.h
@@ -19,6 +19,7 @@
#include "absl/base/config.h"
#include "absl/meta/type_traits.h"
+#include "absl/numeric/bits.h"
#include "absl/numeric/int128.h"
#include "absl/random/internal/fastmath.h"
#include "absl/random/internal/iostream_state_saver.h"
@@ -220,48 +221,27 @@ class pcg_engine {
template <uint64_t kMultA, uint64_t kMultB, uint64_t kIncA, uint64_t kIncB>
class pcg128_params {
public:
-#if ABSL_HAVE_INTRINSIC_INT128
- using state_type = __uint128_t;
- static inline constexpr state_type make_u128(uint64_t a, uint64_t b) {
- return (static_cast<__uint128_t>(a) << 64) | b;
- }
-#else
using state_type = absl::uint128;
- static inline constexpr state_type make_u128(uint64_t a, uint64_t b) {
- return absl::MakeUint128(a, b);
- }
-#endif
-
static inline constexpr state_type multiplier() {
- return make_u128(kMultA, kMultB);
+ return absl::MakeUint128(kMultA, kMultB);
}
static inline constexpr state_type increment() {
- return make_u128(kIncA, kIncB);
+ return absl::MakeUint128(kIncA, kIncB);
}
};
// Implementation of the PCG xsl_rr_128_64 128-bit mixing function, which
// accepts an input of state_type and mixes it into an output of result_type.
struct pcg_xsl_rr_128_64 {
-#if ABSL_HAVE_INTRINSIC_INT128
- using state_type = __uint128_t;
-#else
using state_type = absl::uint128;
-#endif
using result_type = uint64_t;
inline uint64_t operator()(state_type state) {
// This is equivalent to the xsl_rr_128_64 mixing function.
-#if ABSL_HAVE_INTRINSIC_INT128
uint64_t rotate = static_cast<uint64_t>(state >> 122u);
state ^= state >> 64;
uint64_t s = static_cast<uint64_t>(state);
-#else
- uint64_t h = Uint128High64(state);
- uint64_t rotate = h >> 58u;
- uint64_t s = Uint128Low64(state) ^ h;
-#endif
- return random_internal::rotr(s, rotate);
+ return rotr(s, static_cast<int>(rotate));
}
};
@@ -281,8 +261,8 @@ struct pcg_xsh_rr_64_32 {
using state_type = uint64_t;
using result_type = uint32_t;
inline uint32_t operator()(uint64_t state) {
- return random_internal::rotr(
- static_cast<uint32_t>(((state >> 18) ^ state) >> 27), state >> 59);
+ return rotr(static_cast<uint32_t>(((state >> 18) ^ state) >> 27),
+ state >> 59);
}
};