Merge pull request #182 from tevador/pr-restore-fpstate

Preserve floating point state when calling randomx_calculate_hash
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tevador 2020-05-16 23:19:37 +02:00 committed by GitHub
commit 7741eb1e97
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5 changed files with 39 additions and 0 deletions

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@ -157,6 +157,21 @@ void rx_set_rounding_mode(uint32_t mode) {
}
}
uint32_t rx_get_rounding_mode() {
switch (fegetround()) {
case FE_DOWNWARD:
return RoundDown;
case FE_UPWARD:
return RoundUp;
case FE_TOWARDZERO:
return RoundToZero;
case FE_TONEAREST:
return RoundToNearest;
default:
UNREACHABLE;
}
}
#endif
#ifdef RANDOMX_USE_X87

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@ -173,6 +173,10 @@ FORCE_INLINE void rx_set_rounding_mode(uint32_t mode) {
_mm_setcsr(rx_mxcsr_default | (mode << 13));
}
FORCE_INLINE uint32_t rx_get_rounding_mode() {
return (_mm_getcsr() >> 13) & 3;
}
#elif defined(__PPC64__) && defined(__ALTIVEC__) && defined(__VSX__) //sadly only POWER7 and newer will be able to use SIMD acceleration. Earlier processors cant use doubles or 64 bit integers with SIMD
#include <cstdint>
#include <stdexcept>
@ -736,6 +740,8 @@ void rx_reset_float_state();
void rx_set_rounding_mode(uint32_t mode);
uint32_t rx_get_rounding_mode();
#endif
double loadDoublePortable(const void* addr);

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@ -36,6 +36,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "cpu.hpp"
#include <cassert>
#include <limits>
#include <cfenv>
extern "C" {
@ -349,6 +350,8 @@ extern "C" {
assert(machine != nullptr);
assert(inputSize == 0 || input != nullptr);
assert(output != nullptr);
fenv_t fpstate;
fegetenv(&fpstate);
alignas(16) uint64_t tempHash[8];
int blakeResult = blake2b(tempHash, sizeof(tempHash), input, inputSize, nullptr, 0);
assert(blakeResult == 0);
@ -361,6 +364,7 @@ extern "C" {
}
machine->run(&tempHash);
machine->getFinalResult(output, RANDOMX_HASH_SIZE);
fesetenv(&fpstate);
}
void randomx_calculate_hash_first(randomx_vm* machine, const void* input, size_t inputSize) {

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@ -246,6 +246,8 @@ RANDOMX_EXPORT void randomx_calculate_hash(randomx_vm *machine, const void *inpu
* and begin the calculation of the next hash.
* randomx_calculate_hash_last will output the hash value of the previous input.
*
* WARNING: These functions may alter the floating point rounding mode of the calling thread.
*
* @param machine is a pointer to a randomx_vm structure. Must not be NULL.
* @param input is a pointer to memory to be hashed. Must not be NULL.
* @param inputSize is the number of bytes to be hashed.

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@ -1051,6 +1051,10 @@ int main() {
assert(cacheMemory[33554431] == 0x1f47f056d05cd99b);
});
if (cache != nullptr)
randomx_release_cache(cache);
cache = randomx_alloc_cache(RANDOMX_FLAG_DEFAULT);
runTest("Hash batch test", RANDOMX_HAVE_COMPILER && stringsEqual(RANDOMX_ARGON_SALT, "RandomX\x03"), []() {
char hash1[RANDOMX_HASH_SIZE];
char hash2[RANDOMX_HASH_SIZE];
@ -1070,6 +1074,14 @@ int main() {
assert(equalsHex(hash3, "c36d4ed4191e617309867ed66a443be4075014e2b061bcdaf9ce7b721d2b77a8"));
});
runTest("Preserve rounding mode", RANDOMX_FREQ_CFROUND > 0, []() {
rx_set_rounding_mode(RoundToNearest);
char hash[RANDOMX_HASH_SIZE];
calcStringHash("test key 000", "Lorem ipsum dolor sit amet", &hash);
assert(equalsHex(hash, "300a0adb47603dedb42228ccb2b211104f4da45af709cd7547cd049e9489c969"));
assert(rx_get_rounding_mode() == RoundToNearest);
});
randomx_destroy_vm(vm);
vm = nullptr;