Files
asmjit/test/asmjit_test_random.h
kobalicek 2ff454d415 [abi] AsmJit v1.17 - cumulative & breaking changes
* Reworked register operands - all vector registers are now
    platform::Vec deriving from UniVec (universal vector operand),
    additionally, there is no platform::Reg, instead asmjit::Reg
    provides all necessary features to make it a base register for
    each target architecture
  * Reworked casting between registers - now architecture agnostic
    names are preferred - use Gp32 instead of Gpd or GpW, Gp64
    instead of Gpq and GpX, etc...
  * Reworked vector registers and their names - architecture
    agnostic naming is now preferred Vec32, Vec64, Vec128, etc...
  * Reworked naming conventions used across AsmJit - for clarity
    Identifiers are now prefixed with the type, like sectionId(),
    labelId(), etc...
  * Reworked how Zone and ZoneAllocator are used across AsmJit,
    prefering Zone in most cases and ZoneAllocator only for
    containers - this change alone achieves around 5% better
    performance of Builder and Compiler
  * Reworked LabelEntry - decreased the size of the base entry
    to 16 bytes for anonymous and unnamed labels. Avoided an
    indirection when using labelEntries() - LabelEntry is now
    a value and not a pointer
  * Renamed LabelLink to Fixup
  * Added a new header <asmjit/host.h> which would include
    <asmjit/core.h> + target tools for the host architecture,
    if enabled and supported
  * Added new AArch64 instructions (BTI, CSSC, CHKFEAT)
  * Added a mvn_ alternative of mvn instruction (fix for Windows
    ARM64 SDK)
  * Added more AArch64 CPU features to CpuInfo
  * Added better support for Apple CPU detection (Apple M3, M4)
  * Added a new benchmarking tool asmjit_bench_overhead, which
    benchmarks the overhead of CodeHolder::init()/reset() and
    creating/attaching emitters to it. Thanks to the benchmark the
    most common code-paths were optimized
  * Added a new benchmarking tool asmjit_bench_regalloc, which
    aims to benchmark the cost and complexity of register allocation.
  * Renamed asmjit_test_perf to asmjit_bench_codegen to make it
    clear what is a test and what is a benchmark
2025-06-15 16:45:37 +02:00

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2.0 KiB
C++

// This file is part of AsmJit project <https://asmjit.com>
//
// See <asmjit/core.h> or LICENSE.md for license and copyright information
// SPDX-License-Identifier: Zlib
#ifndef ASMJIT_TEST_RANDOM_H_INCLUDED
#define ASMJIT_TEST_RANDOM_H_INCLUDED
#include <stdint.h>
#include <string.h>
namespace TestUtils {
namespace {
// A pseudo random number generator based on a paper by Sebastiano Vigna:
// http://vigna.di.unimi.it/ftp/papers/xorshiftplus.pdf
class Random {
public:
// Constants suggested as `23/18/5`.
static inline constexpr uint32_t kStep1_SHL = 23;
static inline constexpr uint32_t kStep2_SHR = 18;
static inline constexpr uint32_t kStep3_SHR = 5;
uint64_t _state[2];
inline explicit Random(uint64_t seed = 0) noexcept { reset(seed); }
inline Random(const Random& other) noexcept = default;
inline void reset(uint64_t seed = 0) noexcept {
// The number is arbitrary, it means nothing.
constexpr uint64_t kZeroSeed = 0x1F0A2BE71D163FA0u;
// Generate the state data by using splitmix64.
for (uint32_t i = 0; i < 2; i++) {
seed += 0x9E3779B97F4A7C15u;
uint64_t x = seed;
x = (x ^ (x >> 30)) * 0xBF58476D1CE4E5B9u;
x = (x ^ (x >> 27)) * 0x94D049BB133111EBu;
x = (x ^ (x >> 31));
_state[i] = x != 0 ? x : kZeroSeed;
}
}
inline uint32_t nextUInt32() noexcept {
return uint32_t(nextUInt64() >> 32);
}
inline uint64_t nextUInt64() noexcept {
uint64_t x = _state[0];
uint64_t y = _state[1];
x ^= x << kStep1_SHL;
y ^= y >> kStep3_SHR;
x ^= x >> kStep2_SHR;
x ^= y;
_state[0] = y;
_state[1] = x;
return x + y;
}
inline double nextDouble() noexcept {
constexpr uint32_t kMantissaShift = 64 - 52;
constexpr uint64_t kExpMsk = 0x3FF0000000000000u;
uint64_t u = (nextUInt64() >> kMantissaShift) | kExpMsk;
double d = 0.0;
memcpy(&d, &u, 8);
return d - 1.0;
}
};
} // {anonymous}
} // {TestUtils}
#endif // ASMJIT_TEST_RANDOM_H_INCLUDED