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FioraAeterna/gist:0329ce18a51d734b6a54

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gistfile1.diff
diff --git a/Source/Core/Core/PowerPC/Interpreter/Interpreter.h b/Source/Core/Core/PowerPC/Interpreter/Interpreter.h
index 3afaaf9..74ca9c7 100644
--- a/Source/Core/Core/PowerPC/Interpreter/Interpreter.h
+++ b/Source/Core/Core/PowerPC/Interpreter/Interpreter.h
@@ -297,7 +297,8 @@ public:
static void RunTable59(UGeckoInstruction _instCode);
static void RunTable63(UGeckoInstruction _instCode);
- static u32 Helper_Carry(u32 _uValue1, u32 _uValue2);
+ static u32 Helper_Carry(u32 a, u32 b, u32 c);
+ static u32 Helper_Overflow(u32 a, u32 b, u32 c);
private:
// flag helper
diff --git a/Source/Core/Core/PowerPC/Interpreter/Interpreter_Integer.cpp b/Source/Core/Core/PowerPC/Interpreter/Interpreter_Integer.cpp
index 37b1a46..1dabaf7 100644
--- a/Source/Core/Core/PowerPC/Interpreter/Interpreter_Integer.cpp
+++ b/Source/Core/Core/PowerPC/Interpreter/Interpreter_Integer.cpp
@@ -22,9 +22,16 @@ void Interpreter::Helper_UpdateCRx(int idx, u32 value)
PowerPC::ppcState.cr_val[idx] = cr_val;
}
-u32 Interpreter::Helper_Carry(u32 _uValue1, u32 _uValue2)
+u32 Interpreter::Helper_Carry(u32 a, u32 b, u32 c)
{
- return _uValue2 > (~_uValue1);
+ u64 res = (u64)a + (u64)b + (u64)c;
+ return res != (u32)res;
+}
+
+u32 Interpreter::Helper_Overflow(u32 a, u32 b, u32 c)
+{
+ s64 res = (s64)(s32)a + (s64)(s32)b + (s64)(s32)c;
+ return res != (s32)res;
}
u32 Interpreter::Helper_Mask(int mb, int me)
@@ -54,9 +61,8 @@ void Interpreter::addic(UGeckoInstruction _inst)
{
u32 a = rGPR[_inst.RA];
u32 imm = (u32)(s32)_inst.SIMM_16;
- // TODO(ector): verify this thing
rGPR[_inst.RD] = a + imm;
- SetCarry(Helper_Carry(a, imm));
+ SetCarry(Helper_Carry(a, imm, 0));
}
void Interpreter::addic_rc(UGeckoInstruction _inst)
@@ -126,21 +132,10 @@ void Interpreter::oris(UGeckoInstruction _inst)
void Interpreter::subfic(UGeckoInstruction _inst)
{
-/* u32 rra = ~rGPR[_inst.RA];
- s32 immediate = (s16)_inst.SIMM_16 + 1;
-
-// #define CALC_XER_CA(X,Y) (((X) + (Y) < X) ? SET_XER_CA : CLEAR_XER_CA)
- if ((rra + immediate) < rra)
- SetCarry(1);
- else
- SetCarry(0);
-
- rGPR[_inst.RD] = rra - immediate;
-*/
-
- s32 immediate = _inst.SIMM_16;
- rGPR[_inst.RD] = immediate - (int)rGPR[_inst.RA];
- SetCarry((rGPR[_inst.RA] == 0) || (Helper_Carry(0 - rGPR[_inst.RA], immediate)));
+ u32 a = rGPR[_inst.RA];
+ u32 imm = (s32)_inst.SIMM_16;
+ rGPR[_inst.RD] = ~a + imm + 1;
+ SetCarry(Helper_Carry(~a, imm, 1));
}
void Interpreter::twi(UGeckoInstruction _inst)
@@ -229,7 +224,7 @@ void Interpreter::cmp(UGeckoInstruction _inst)
fTemp = 0x2;
if (GetXER_SO())
- PanicAlert("cmp getting overflow flag"); // fTemp |= 0x1
+ fTemp |= 0x1;
SetCRField(_inst.CRFD, fTemp);
}
@@ -247,7 +242,7 @@ void Interpreter::cmpl(UGeckoInstruction _inst)
fTemp = 0x2;
if (GetXER_SO())
- PanicAlert("cmpl getting overflow flag"); // fTemp |= 0x1;
+ fTemp |= 0x1;
SetCRField(_inst.CRFD, fTemp);
}
@@ -439,10 +434,12 @@ void Interpreter::xorx(UGeckoInstruction _inst)
void Interpreter::addx(UGeckoInstruction _inst)
{
- rGPR[_inst.RD] = rGPR[_inst.RA] + rGPR[_inst.RB];
+ u32 a = rGPR[_inst.RA];
+ u32 b = rGPR[_inst.RB];
+ rGPR[_inst.RD] = a + b;
if (_inst.OE)
- PanicAlert("OE: addx");
+ SetOverflow(Helper_Overflow(a, b, 0));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -453,10 +450,10 @@ void Interpreter::addcx(UGeckoInstruction _inst)
u32 a = rGPR[_inst.RA];
u32 b = rGPR[_inst.RB];
rGPR[_inst.RD] = a + b;
- SetCarry(Helper_Carry(a,b));
+ SetCarry(Helper_Carry(a, b, 0));
if (_inst.OE)
- PanicAlert("OE: addcx");
+ SetOverflow(Helper_Overflow(a, b, 0));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -465,13 +462,13 @@ void Interpreter::addcx(UGeckoInstruction _inst)
void Interpreter::addex(UGeckoInstruction _inst)
{
int carry = GetCarry();
- int a = rGPR[_inst.RA];
- int b = rGPR[_inst.RB];
+ u32 a = rGPR[_inst.RA];
+ u32 b = rGPR[_inst.RB];
rGPR[_inst.RD] = a + b + carry;
- SetCarry(Helper_Carry(a, b) || (carry != 0 && Helper_Carry(a + b, carry)));
+ SetCarry(Helper_Carry(a, b, carry));
if (_inst.OE)
- PanicAlert("OE: addex");
+ SetOverflow(Helper_Overflow(a, b, carry));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -480,12 +477,12 @@ void Interpreter::addex(UGeckoInstruction _inst)
void Interpreter::addmex(UGeckoInstruction _inst)
{
int carry = GetCarry();
- int a = rGPR[_inst.RA];
+ u32 a = rGPR[_inst.RA];
rGPR[_inst.RD] = a + carry - 1;
- SetCarry(Helper_Carry(a, carry - 1));
+ SetCarry(Helper_Carry(a, carry, -1));
if (_inst.OE)
- PanicAlert("OE: addmex");
+ SetOverflow(Helper_Overflow(a, carry, -1));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -494,12 +491,12 @@ void Interpreter::addmex(UGeckoInstruction _inst)
void Interpreter::addzex(UGeckoInstruction _inst)
{
int carry = GetCarry();
- int a = rGPR[_inst.RA];
+ u32 a = rGPR[_inst.RA];
rGPR[_inst.RD] = a + carry;
- SetCarry(Helper_Carry(a, carry));
+ SetCarry(Helper_Carry(a, carry, 0));
if (_inst.OE)
- PanicAlert("OE: addzex");
+ SetOverflow(Helper_Overflow(a, carry, 0));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -513,11 +510,7 @@ void Interpreter::divwx(UGeckoInstruction _inst)
if (b == 0 || ((u32)a == 0x80000000 && b == -1))
{
if (_inst.OE)
- {
- // should set OV
- PanicAlert("OE: divwx");
- }
-
+ SetOverflow(1);
if (((u32)a & 0x80000000) && b == 0)
rGPR[_inst.RD] = -1;
else
@@ -525,6 +518,8 @@ void Interpreter::divwx(UGeckoInstruction _inst)
}
else
{
+ if (_inst.OE)
+ SetOverflow(0);
rGPR[_inst.RD] = (u32)(a / b);
}
@@ -538,20 +533,9 @@ void Interpreter::divwux(UGeckoInstruction _inst)
u32 a = rGPR[_inst.RA];
u32 b = rGPR[_inst.RB];
- if (b == 0)
- {
- if (_inst.OE)
- {
- // should set OV
- PanicAlert("OE: divwux");
- }
-
- rGPR[_inst.RD] = 0;
- }
- else
- {
- rGPR[_inst.RD] = a / b;
- }
+ if (_inst.OE)
+ SetOverflow(b == 0);
+ rGPR[_inst.RD] = b == 0 ? 0 : a / b;
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -581,13 +565,13 @@ void Interpreter::mulhwux(UGeckoInstruction _inst)
void Interpreter::mullwx(UGeckoInstruction _inst)
{
- u32 a = rGPR[_inst.RA];
- u32 b = rGPR[_inst.RB];
- u32 d = (u32)((s32)a * (s32)b);
- rGPR[_inst.RD] = d;
+ s64 a = rGPR[_inst.RA];
+ s64 b = rGPR[_inst.RB];
+ s64 res = a * b;
+ rGPR[_inst.RD] = (s32)res;
if (_inst.OE)
- PanicAlert("OE: mullwx");
+ SetOverflow(res != (s32)res);
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -597,11 +581,8 @@ void Interpreter::negx(UGeckoInstruction _inst)
{
rGPR[_inst.RD] = (~rGPR[_inst.RA]) + 1;
- if (rGPR[_inst.RD] == 0x80000000)
- {
- if (_inst.OE)
- PanicAlert("OE: negx");
- }
+ if (_inst.OE)
+ SetOverflow(rGPR[_inst.RD] == 0x80000000);
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -609,10 +590,12 @@ void Interpreter::negx(UGeckoInstruction _inst)
void Interpreter::subfx(UGeckoInstruction _inst)
{
- rGPR[_inst.RD] = rGPR[_inst.RB] - rGPR[_inst.RA];
+ u32 a = rGPR[_inst.RA];
+ u32 b = rGPR[_inst.RB];
+ rGPR[_inst.RD] = ~a + b + 1;
if (_inst.OE)
- PanicAlert("OE: subfx");
+ SetOverflow(Helper_Overflow(~a, b, 1));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -622,11 +605,11 @@ void Interpreter::subfcx(UGeckoInstruction _inst)
{
u32 a = rGPR[_inst.RA];
u32 b = rGPR[_inst.RB];
- rGPR[_inst.RD] = b - a;
- SetCarry(a == 0 || Helper_Carry(b, 0-a));
+ rGPR[_inst.RD] = ~a + b + 1;
+ SetCarry(Helper_Carry(~a, b, 1));
if (_inst.OE)
- PanicAlert("OE: subfcx");
+ SetOverflow(Helper_Overflow(~a, b, 1));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -637,11 +620,11 @@ void Interpreter::subfex(UGeckoInstruction _inst)
u32 a = rGPR[_inst.RA];
u32 b = rGPR[_inst.RB];
int carry = GetCarry();
- rGPR[_inst.RD] = (~a) + b + carry;
- SetCarry(Helper_Carry(~a, b) || Helper_Carry((~a) + b, carry));
+ rGPR[_inst.RD] = ~a + b + carry;
+ SetCarry(Helper_Carry(~a, b, carry));
if (_inst.OE)
- PanicAlert("OE: subfex");
+ SetOverflow(Helper_Overflow(~a, b, carry));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -650,13 +633,13 @@ void Interpreter::subfex(UGeckoInstruction _inst)
// sub from minus one
void Interpreter::subfmex(UGeckoInstruction _inst)
{
- u32 a = rGPR[_inst.RA];
+ s32 a = rGPR[_inst.RA];
int carry = GetCarry();
- rGPR[_inst.RD] = (~a) + carry - 1;
- SetCarry(Helper_Carry(~a, carry - 1));
+ rGPR[_inst.RD] = ~a + carry - 1;
+ SetCarry(Helper_Carry(~a, carry, -1));
if (_inst.OE)
- PanicAlert("OE: subfmex");
+ SetOverflow(Helper_Overflow(~a, carry, -1));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
@@ -667,11 +650,11 @@ void Interpreter::subfzex(UGeckoInstruction _inst)
{
u32 a = rGPR[_inst.RA];
int carry = GetCarry();
- rGPR[_inst.RD] = (~a) + carry;
- SetCarry(Helper_Carry(~a, carry));
+ rGPR[_inst.RD] = ~a + carry;
+ SetCarry(Helper_Carry(~a, carry, 0));
if (_inst.OE)
- PanicAlert("OE: subfzex");
+ SetOverflow(Helper_Overflow(~a, carry, 0));
if (_inst.Rc)
Helper_UpdateCR0(rGPR[_inst.RD]);
diff --git a/Source/Core/Core/PowerPC/PowerPC.h b/Source/Core/Core/PowerPC/PowerPC.h
index 69eb0da..071582d 100644
--- a/Source/Core/Core/PowerPC/PowerPC.h
+++ b/Source/Core/Core/PowerPC/PowerPC.h
@@ -306,6 +306,20 @@ inline int GetXER_SO()
inline void SetXER_SO(int value)
{
+ PowerPC::ppcState.xer_so_ov &= ~2;
+ PowerPC::ppcState.xer_so_ov |= value << 1;
+}
+
+inline int GetOverflow()
+{
+ return PowerPC::ppcState.xer_so_ov & 1;
+}
+
+inline void SetOverflow(int value)
+{
+ PowerPC::ppcState.xer_so_ov &= ~1;
+ PowerPC::ppcState.xer_so_ov |= value;
+ // update SO, too
PowerPC::ppcState.xer_so_ov |= value << 1;
}
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