diff --git a/src/InterpretedVirtualMachine.cpp b/src/InterpretedVirtualMachine.cpp
index 6a97d7d..f44a391 100644
--- a/src/InterpretedVirtualMachine.cpp
+++ b/src/InterpretedVirtualMachine.cpp
@@ -29,6 +29,7 @@ along with RandomX. If not, see.
#include
#include
#include
+#include
#include "intrinPortable.h"
#include "reciprocal.h"
#ifdef STATS
@@ -108,9 +109,13 @@ namespace RandomX {
}
}
+ static bool isDenormal(double x) {
+ return std::fpclassify(x) == FP_SUBNORMAL;
+ }
+
FORCE_INLINE void InterpretedVirtualMachine::executeBytecode(int i, int_reg_t(&r)[8], __m128d (&f)[4], __m128d (&e)[4], __m128d (&a)[4]) {
auto& ibc = byteCode[i];
- if(trace) printState(r, f, e, a);
+ //if(trace) printState(r, f, e, a);
switch (ibc.type)
{
case InstructionType::IADD_R: {
@@ -219,9 +224,8 @@ namespace RandomX {
} break;
case InstructionType::FDIV_M: {
- __m128d fsrc = _mm_abs(load_cvt_i32x2(scratchpad + (*ibc.isrc & ibc.memMask)));
- __m128d fdst = _mm_div_pd(*ibc.fdst, fsrc);
- *ibc.fdst = _mm_max_pd(fdst, _mm_set_pd(DBL_MIN, DBL_MIN));
+ __m128d fsrc = ieee_set_exponent<-240>(load_cvt_i32x2(scratchpad + (*ibc.isrc & ibc.memMask)));
+ *ibc.fdst = _mm_div_pd(*ibc.fdst, fsrc);
} break;
case InstructionType::FSQRT_R: {
@@ -258,6 +262,18 @@ namespace RandomX {
else //if(ibc.type >= 20 && ibc.type <= 30)
print(0);
}
+#ifdef FPUCHECK
+ if (ibc.type >= 26 && ibc.type <= 30) {
+ double lo = *(((double*)ibc.fdst) + 0);
+ double hi = *(((double*)ibc.fdst) + 1);
+ if (lo <= 0 || hi <= 0) {
+ std::stringstream ss;
+ ss << "Underflow in operation " << ibc.type;
+ printState(r, f, e, a);
+ throw std::runtime_error(ss.str());
+ }
+ }
+#endif
}
void InterpretedVirtualMachine::execute() {
@@ -304,10 +320,10 @@ namespace RandomX {
f[1] = load_cvt_i32x2(scratchpad + spAddr1 + 8);
f[2] = load_cvt_i32x2(scratchpad + spAddr1 + 16);
f[3] = load_cvt_i32x2(scratchpad + spAddr1 + 24);
- e[0] = _mm_abs(load_cvt_i32x2(scratchpad + spAddr1 + 32));
- e[1] = _mm_abs(load_cvt_i32x2(scratchpad + spAddr1 + 40));
- e[2] = _mm_abs(load_cvt_i32x2(scratchpad + spAddr1 + 48));
- e[3] = _mm_abs(load_cvt_i32x2(scratchpad + spAddr1 + 56));
+ e[0] = ieee_set_exponent<-240>(load_cvt_i32x2(scratchpad + spAddr1 + 32));
+ e[1] = ieee_set_exponent<-240>(load_cvt_i32x2(scratchpad + spAddr1 + 40));
+ e[2] = ieee_set_exponent<-240>(load_cvt_i32x2(scratchpad + spAddr1 + 48));
+ e[3] = ieee_set_exponent<-240>(load_cvt_i32x2(scratchpad + spAddr1 + 56));
if (trace) {
std::cout << "iteration " << std::dec << iter << std::endl;
@@ -357,10 +373,22 @@ namespace RandomX {
store64(scratchpad + spAddr1 + 48, r[6]);
store64(scratchpad + spAddr1 + 56, r[7]);
- f[0] = _mm_mul_pd(f[0], e[0]);
- f[1] = _mm_mul_pd(f[1], e[1]);
- f[2] = _mm_mul_pd(f[2], e[2]);
- f[3] = _mm_mul_pd(f[3], e[3]);
+ f[0] = _mm_xor_pd(f[0], e[0]);
+ f[1] = _mm_xor_pd(f[1], e[1]);
+ f[2] = _mm_xor_pd(f[2], e[2]);
+ f[3] = _mm_xor_pd(f[3], e[3]);
+
+#ifdef FPUCHECK
+ for(int i = 0; i < 4; ++i) {
+ double lo = *(((double*)&f[i]) + 0);
+ double hi = *(((double*)&f[i]) + 1);
+ if (isDenormal(lo) || isDenormal(hi)) {
+ std::stringstream ss;
+ ss << "Denormal f" << i;
+ throw std::runtime_error(ss.str());
+ }
+ }
+#endif
_mm_store_pd((double*)(scratchpad + spAddr0 + 0), f[0]);
_mm_store_pd((double*)(scratchpad + spAddr0 + 16), f[1]);
diff --git a/src/intrinPortable.h b/src/intrinPortable.h
index aea0335..3bee98f 100644
--- a/src/intrinPortable.h
+++ b/src/intrinPortable.h
@@ -46,11 +46,6 @@ constexpr uint64_t signExtend2sCompl(uint32_t x) {
#include
#endif
-inline __m128d _mm_abs(__m128d xd) {
- const __m128d absmask = _mm_castsi128_pd(_mm_set1_epi64x(~(1LL << 63)));
- return _mm_and_pd(xd, absmask);
-}
-
#define PREFETCHNTA(x) _mm_prefetch((const char *)(x), _MM_HINT_NTA)
#else
@@ -159,6 +154,20 @@ inline __m128d _mm_xor_pd(__m128d a, __m128d b) {
return x;
}
+inline __m128d _mm_and_pd(__m128d a, __m128d b) {
+ __m128d x;
+ x.i.u64[0] = a.i.u64[0] & b.i.u64[0];
+ x.i.u64[1] = a.i.u64[1] & b.i.u64[1];
+ return x;
+}
+
+inline __m128d _mm_or_pd(__m128d a, __m128d b) {
+ __m128d x;
+ x.i.u64[0] = a.i.u64[0] | b.i.u64[0];
+ x.i.u64[1] = a.i.u64[1] | b.i.u64[1];
+ return x;
+}
+
inline __m128d _mm_set_pd(double e1, double e0) {
__m128d x;
x.lo = e0;
@@ -302,6 +311,18 @@ inline __m128d load_cvt_i32x2(const void* addr) {
return _mm_cvtepi32_pd(ix);
}
+template
+__m128d ieee_set_exponent(__m128d x) {
+ static_assert(E > -1023, "Invalid exponent value");
+ constexpr uint64_t mantissaMask64 = (1ULL << 52) - 1;
+ const __m128d mantissaMask = _mm_castsi128_pd(_mm_set_epi64x(mantissaMask64, mantissaMask64));
+ constexpr uint64_t exponent64 = (uint64_t)(E + 1023U) << 52;
+ const __m128d exponentMask = _mm_castsi128_pd(_mm_set_epi64x(exponent64, exponent64));
+ x = _mm_and_pd(x, mantissaMask);
+ x = _mm_or_pd(x, exponentMask);
+ return x;
+}
+
double loadDoublePortable(const void* addr);
uint64_t mulh(uint64_t, uint64_t);