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Interpreter_Integer: Handle overflow flag when OE bit is set in add, addc, adde, addme, and addze

This commit is contained in:
Lioncash 2018-03-21 21:26:10 -04:00
parent 23bc50704a
commit 9d21425449
1 changed files with 44 additions and 24 deletions
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68
Source/Core/Core/PowerPC/Interpreter/Interpreter_Integer.cpp
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@ -422,72 +422,92 @@ void Interpreter::xorx(UGeckoInstruction inst)
Helper_UpdateCR0(rGPR[inst.RA]); Helper_UpdateCR0(rGPR[inst.RA]);
} }
static bool HasAddOverflowed(u32 x, u32 y, u32 result)
{
// If x and y have the same sign, but the result is different
// then an overflow has occurred.
return (((x ^ result) & (y ^ result)) >> 31) != 0;
}
void Interpreter::addx(UGeckoInstruction inst) void Interpreter::addx(UGeckoInstruction inst)
{ {
rGPR[inst.RD] = rGPR[inst.RA] + rGPR[inst.RB]; const u32 a = rGPR[inst.RA];
const u32 b = rGPR[inst.RB];
const u32 result = a + b;
rGPR[inst.RD] = result;
if (inst.OE) if (inst.OE)
PanicAlert("OE: addx"); SetXER_OV(HasAddOverflowed(a, b, result));
if (inst.Rc) if (inst.Rc)
Helper_UpdateCR0(rGPR[inst.RD]); Helper_UpdateCR0(result);
} }
void Interpreter::addcx(UGeckoInstruction inst) void Interpreter::addcx(UGeckoInstruction inst)
{ {
u32 a = rGPR[inst.RA]; const u32 a = rGPR[inst.RA];
u32 b = rGPR[inst.RB]; const u32 b = rGPR[inst.RB];
rGPR[inst.RD] = a + b; const u32 result = a + b;
rGPR[inst.RD] = result;
SetCarry(Helper_Carry(a, b)); SetCarry(Helper_Carry(a, b));
if (inst.OE) if (inst.OE)
PanicAlert("OE: addcx"); SetXER_OV(HasAddOverflowed(a, b, result));
if (inst.Rc) if (inst.Rc)
Helper_UpdateCR0(rGPR[inst.RD]); Helper_UpdateCR0(result);
} }
void Interpreter::addex(UGeckoInstruction inst) void Interpreter::addex(UGeckoInstruction inst)
{ {
int carry = GetCarry(); const u32 carry = GetCarry();
int a = rGPR[inst.RA]; const u32 a = rGPR[inst.RA];
int b = rGPR[inst.RB]; const u32 b = rGPR[inst.RB];
rGPR[inst.RD] = a + b + carry; const u32 result = a + b + carry;
rGPR[inst.RD] = result;
SetCarry(Helper_Carry(a, b) || (carry != 0 && Helper_Carry(a + b, carry))); SetCarry(Helper_Carry(a, b) || (carry != 0 && Helper_Carry(a + b, carry)));
if (inst.OE) if (inst.OE)
PanicAlert("OE: addex"); SetXER_OV(HasAddOverflowed(a, b, result));
if (inst.Rc) if (inst.Rc)
Helper_UpdateCR0(rGPR[inst.RD]); Helper_UpdateCR0(result);
} }
void Interpreter::addmex(UGeckoInstruction inst) void Interpreter::addmex(UGeckoInstruction inst)
{ {
int carry = GetCarry(); const u32 carry = GetCarry();
int a = rGPR[inst.RA]; const u32 a = rGPR[inst.RA];
rGPR[inst.RD] = a + carry - 1; const u32 b = 0xFFFFFFFF;
const u32 result = a + b + carry;
rGPR[inst.RD] = result;
SetCarry(Helper_Carry(a, carry - 1)); SetCarry(Helper_Carry(a, carry - 1));
if (inst.OE) if (inst.OE)
PanicAlert("OE: addmex"); SetXER_OV(HasAddOverflowed(a, b, result));
if (inst.Rc) if (inst.Rc)
Helper_UpdateCR0(rGPR[inst.RD]); Helper_UpdateCR0(result);
} }
void Interpreter::addzex(UGeckoInstruction inst) void Interpreter::addzex(UGeckoInstruction inst)
{ {
int carry = GetCarry(); const u32 carry = GetCarry();
int a = rGPR[inst.RA]; const u32 a = rGPR[inst.RA];
rGPR[inst.RD] = a + carry; const u32 result = a + carry;
rGPR[inst.RD] = result;
SetCarry(Helper_Carry(a, carry)); SetCarry(Helper_Carry(a, carry));
if (inst.OE) if (inst.OE)
PanicAlert("OE: addzex"); SetXER_OV(HasAddOverflowed(a, 0, result));
if (inst.Rc) if (inst.Rc)
Helper_UpdateCR0(rGPR[inst.RD]); Helper_UpdateCR0(result);
} }
void Interpreter::divwx(UGeckoInstruction inst) void Interpreter::divwx(UGeckoInstruction inst)