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-rw-r--r--util/host-utils.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/util/host-utils.c b/util/host-utils.c
index 37c1706de6..ee57ef55f6 100644
--- a/util/host-utils.c
+++ b/util/host-utils.c
@@ -124,4 +124,41 @@ int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor)
return 0;
}
}
+
+int divs128(int64_t *plow, int64_t *phigh, int64_t divisor)
+{
+ int sgn_dvdnd = *phigh < 0;
+ int sgn_divsr = divisor < 0;
+ int overflow = 0;
+
+ if (sgn_dvdnd) {
+ *plow = ~(*plow);
+ *phigh = ~(*phigh);
+ if (*plow == (int64_t)-1) {
+ *plow = 0;
+ (*phigh)++;
+ } else {
+ (*plow)++;
+ }
+ }
+
+ if (sgn_divsr) {
+ divisor = 0 - divisor;
+ }
+
+ overflow = divu128((uint64_t *)plow, (uint64_t *)phigh, (uint64_t)divisor);
+
+ if (sgn_dvdnd ^ sgn_divsr) {
+ *plow = 0 - *plow;
+ }
+
+ if (!overflow) {
+ if ((*plow < 0) ^ (sgn_dvdnd ^ sgn_divsr)) {
+ overflow = 1;
+ }
+ }
+
+ return overflow;
+}
+
#endif /* !CONFIG_INT128 */