From 8c880c339000010260a927c3a0f28f9049b8a0b8 Mon Sep 17 00:00:00 2001 From: mrb0nk500 Date: Mon, 5 Oct 2020 11:15:21 -0400 Subject: - Fixed the rotate instructions. The carry flag is now set properly, and the rotation now is set properly by the carry flag, even for shift values greater than one. - Added a test program for properly testing the rotate instructions. --- sux.h | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) (limited to 'sux.h') 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; } -- cgit v1.2.3-13-gbd6f