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Fix edge case in the division engine, fix edge case in the CPU (#1003)

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* Fixed division edge case: Div64/32 and Div64/64 set the remainder to 0 if dividend == INT64_MIN && divisor == -1

* Fixed CPU edge case where ARM9 ALU ops would switch to Thumb even when they shouldn't

* Only clear the lowest bit of the jump address in ALU ops with rd==15 (on recommendation of RSDuck)
This commit is contained in:
wheremyfoodat
2021-02-20 00:58:41 +02:00
committed by GitHub
parent a8b2c22306
commit 03b465c5e2
2 changed files with 14 additions and 12 deletions
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24
src/ARMInterpreter_ALU.cpp
View File

@ -290,7 +290,7 @@ void A_##x##_REG_ROR_REG(ARM* cpu) \
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -321,7 +321,7 @@ A_IMPLEMENT_ALU_OP(AND,_S)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -352,7 +352,7 @@ A_IMPLEMENT_ALU_OP(EOR,_S)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -385,7 +385,7 @@ A_IMPLEMENT_ALU_OP(SUB,)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -418,7 +418,7 @@ A_IMPLEMENT_ALU_OP(RSB,)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -451,7 +451,7 @@ A_IMPLEMENT_ALU_OP(ADD,)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -486,7 +486,7 @@ A_IMPLEMENT_ALU_OP(ADC,)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -521,7 +521,7 @@ A_IMPLEMENT_ALU_OP(SBC,)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -600,7 +600,7 @@ A_IMPLEMENT_ALU_TEST(CMN,)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -629,7 +629,7 @@ A_IMPLEMENT_ALU_OP(ORR,_S)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(b); \ cpu->JumpTo(b & ~1); \
} \ } \
else \ else \
{ \ { \
@ -673,7 +673,7 @@ void A_MOV_REG_LSL_IMM_DBG(ARM* cpu)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(res); \ cpu->JumpTo(res & ~1); \
} \ } \
else \ else \
{ \ { \
@ -703,7 +703,7 @@ A_IMPLEMENT_ALU_OP(BIC,_S)
if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \ if (c) cpu->AddCycles_CI(c); else cpu->AddCycles_C(); \
if (((cpu->CurInstr>>12) & 0xF) == 15) \ if (((cpu->CurInstr>>12) & 0xF) == 15) \
{ \ { \
cpu->JumpTo(b); \ cpu->JumpTo(b & ~1); \
} \ } \
else \ else \
{ \ { \

2
src/NDS.cpp
View File

@ -1758,6 +1758,7 @@ void DivDone(u32 param)
else if (num == -0x8000000000000000 && den == -1) else if (num == -0x8000000000000000 && den == -1)
{ {
*(s64*)&DivQuotient[0] = 0x8000000000000000; *(s64*)&DivQuotient[0] = 0x8000000000000000;
*(s64*)&DivRemainder[0] = 0;
} }
else else
{ {
@ -1779,6 +1780,7 @@ void DivDone(u32 param)
else if (num == -0x8000000000000000 && den == -1) else if (num == -0x8000000000000000 && den == -1)
{ {
*(s64*)&DivQuotient[0] = 0x8000000000000000; *(s64*)&DivQuotient[0] = 0x8000000000000000;
*(s64*)&DivRemainder[0] = 0;
} }
else else
{ {