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Implement addressing mode 1 ROR with register

This commit is contained in:
Jeffrey Pfau 2013-04-30 01:57:36 -07:00
parent e1963c6e60
commit 337d4dc1e6
1 changed files with 22 additions and 1 deletions
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23
src/arm/isa-arm.c
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@ -76,7 +76,28 @@ static inline void _shiftROR(struct ARMCore* cpu, uint32_t opcode) {
static inline void _shiftRORR(struct ARMCore* cpu, uint32_t opcode) {
int rm = opcode & 0x0000000F;
ARM_STUB;
int rs = (opcode >> 8) & 0x0000000F;
++cpu->cycles;
int shift = cpu->gprs[rs];
if (rs == ARM_PC) {
shift += 4;
}
shift &= 0xFF;
int shiftVal = cpu->gprs[rm];
if (rm == ARM_PC) {
shiftVal += 4;
}
int rotate = shift & 0x1F;
if (!shift) {
cpu->shifterOperand = shiftVal;
cpu->shifterCarryOut = cpu->cpsr.c;
} else if (rotate) {
cpu->shifterOperand = ARM_ROR(shiftVal, rotate);
cpu->shifterCarryOut = (shiftVal >> (rotate - 1)) & 1;
} else {
cpu->shifterOperand = shiftVal;
cpu->shifterCarryOut = ARM_SIGN(shiftVal);
}
}
static inline void _immediate(struct ARMCore* cpu, uint32_t opcode) {