1 files changed, 16 insertions, 6 deletions

diff --git a/sux.h b/sux.h
index 9004c74..744a2cc 100644
--- a/sux.h
+++ b/sux.h
@@ -351,20 +351,30 @@ static inline uint64_t asr(struct sux *cpu, uint64_t reg, uint64_t value, uint8_
 }
 
 static inline uint64_t rol(struct sux *cpu, uint64_t reg, uint64_t value, uint8_t thread) {
-	uint64_t sum = reg << value;
-	sum |= getflag(C);
+	uint64_t sum;
+	uint64_t c = getflag(C);
+	switch (value & 0x3F) {
+		case 0 : return reg;
+		case 1 : sum = (reg << 1) | (c & 1); break;
+		default: sum = (reg << value) | (c << (value-1)) | (reg >> (65-value)); break;
+	}
 	setflag(sum == 0, Z);
 	setflag(sum >> 63, N);
-	setflag(reg >> (uint64_t)(64-value), C);
+	setflag((reg >> (64-value)) & 1, C);
 	return sum;
 }
 
 static inline uint64_t ror(struct sux *cpu, uint64_t reg, uint64_t value, uint8_t thread) {
-	uint64_t sum = reg >> value;
-	sum |= (uint64_t)getflag(C) << (uint64_t)(64-value);
+	uint64_t sum;
+	uint64_t c = getflag(C);
+	switch (value & 0x3F) {
+		case 0 : return reg;
+		case 1 : sum = (reg >> 1) | (c << 63); break;
+		default: sum = (reg >> value) | (c << (64-value)) | (reg << (65-value)); break;
+	}
 	setflag(sum == 0, Z);
 	setflag(sum >> 63, N);
-	setflag(reg & 1, C);
+	setflag((reg >> (value-1)) & 1, C);
 	return sum;
 }