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Ensure shifter carry-out gets bits set right

This commit is contained in:
Jeffrey Pfau 2013-04-30 21:02:56 -07:00
parent f7fbb877e0
commit da489b90f8
1 changed files with 8 additions and 8 deletions
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16
src/arm/isa-arm.c
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@ -18,7 +18,7 @@ static inline void _shiftLSL(struct ARMCore* cpu, uint32_t opcode) {
cpu->shifterCarryOut = cpu->cpsr.c;
} else {
cpu->shifterOperand = cpu->gprs[rm] << immediate;
cpu->shifterCarryOut = cpu->gprs[rm] & (1 << (32 - immediate));
cpu->shifterCarryOut = (cpu->gprs[rm] >> (32 - immediate)) & 1;
}
}
@ -32,10 +32,10 @@ static inline void _shiftLSR(struct ARMCore* cpu, uint32_t opcode) {
int immediate = (opcode & 0x00000F80) >> 7;
if (immediate) {
cpu->shifterOperand = ((uint32_t) cpu->gprs[rm]) >> immediate;
cpu->shifterCarryOut = cpu->gprs[rm] & (1 << (immediate - 1));
cpu->shifterCarryOut = (cpu->gprs[rm] >> (immediate - 1)) & 1;
} else {
cpu->shifterOperand = 0;
cpu->shifterCarryOut = cpu->gprs[rm] & 0x80000000;
cpu->shifterCarryOut = ARM_SIGN(cpu->gprs[rm]);
}
}
@ -49,10 +49,10 @@ static inline void _shiftASR(struct ARMCore* cpu, uint32_t opcode) {
int immediate = (opcode & 0x00000F80) >> 7;
if (immediate) {
cpu->shifterOperand = cpu->gprs[rm] >> immediate;
cpu->shifterCarryOut = cpu->gprs[rm] & (1 << (immediate - 1));
cpu->shifterCarryOut = (cpu->gprs[rm] >> (immediate - 1)) & 1;
} else {
cpu->shifterCarryOut = cpu->gprs[rm] & 0x80000000;
cpu->shifterOperand = cpu->shifterCarryOut >> 31; // Ensure sign extension
cpu->shifterCarryOut = ARM_SIGN(cpu->gprs[rm]);
cpu->shifterOperand = cpu->shifterCarryOut;
}
}
@ -66,7 +66,7 @@ static inline void _shiftROR(struct ARMCore* cpu, uint32_t opcode) {
int immediate = (opcode & 0x00000F80) >> 7;
if (immediate) {
cpu->shifterOperand = ARM_ROR(cpu->gprs[rm], immediate);
cpu->shifterCarryOut = cpu->gprs[rm] & (1 << (immediate - 1));
cpu->shifterCarryOut = (cpu->gprs[rm] >> (immediate - 1)) & 1;
} else {
// RRX
cpu->shifterOperand = (cpu->cpsr.c << 31) | (((uint32_t) cpu->gprs[rm]) >> 1);
@ -255,7 +255,7 @@ void ARMStep(struct ARMCore* cpu) {
} else { \
cpu->cpsr.n = ARM_SIGN(D); \
cpu->cpsr.z = !(D); \
cpu->cpsr.c = !!cpu->shifterCarryOut; \
cpu->cpsr.c = cpu->shifterCarryOut; \
}
#define ARM_NEUTRAL_HI_S(DLO, DHI) \