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Fixed-point FMOD and LOG explicitly return 0 for some invalid inputs

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This is consistent with `fix_Div`'s explicit error handling,
and does not rely on subtle C/C++ `fmod` or `log` IEEE 754 behavior.
This commit is contained in:
Rangi
2026-07-23 00:38:44 -04:00
parent 604c69e048
commit 80c8e77b19
1 changed files with 8 additions and 1 deletions
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src/asm/fixpoint.cpp
+8 -1
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@@ -77,7 +77,11 @@ int32_t fix_Div(int32_t i, int32_t j, int32_t q) {
} }
int32_t fix_Mod(int32_t i, int32_t j, int32_t q) { int32_t fix_Mod(int32_t i, int32_t j, int32_t q) {
return double2fix(fmod(fix2double(i, q), fix2double(j, q)), q); double divisor = fix2double(j, q);
if (fpclassify(divisor) == FP_ZERO) {
return 0;
}
return double2fix(fmod(fix2double(i, q), divisor), q);
} }
int32_t fix_Pow(int32_t i, int32_t j, int32_t q) { int32_t fix_Pow(int32_t i, int32_t j, int32_t q) {
@@ -86,6 +90,9 @@ int32_t fix_Pow(int32_t i, int32_t j, int32_t q) {
int32_t fix_Log(int32_t i, int32_t j, int32_t q) { int32_t fix_Log(int32_t i, int32_t j, int32_t q) {
double divisor = log(fix2double(j, q)); double divisor = log(fix2double(j, q));
if (isnan(divisor) || isinf(divisor)) {
return 0;
}
if (fpclassify(divisor) == FP_ZERO) { if (fpclassify(divisor) == FP_ZERO) {
return INT32_MAX; return INT32_MAX;
} }