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Merge pull request #1035 from FioraAeterna/fixcrxxx

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JIT: fix a corner case in crXXX
This commit is contained in:
Ryan Houdek 2014-09-09 00:58:53 -05:00
commit 6a7e8899d3
1 changed files with 23 additions and 15 deletions
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38
Source/Core/Core/PowerPC/Jit64/Jit_SystemRegisters.cpp
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@ -45,6 +45,17 @@ void Jit64::SetCRFieldBit(int field, int bit, Gen::X64Reg in)
MOV(64, R(RSCRATCH2), PPCSTATE(cr_val[field]));
MOVZX(32, 8, in, R(in));
// Gross but necessary; if the input is totally zero and we set SO or LT,
// or even just add the (1<<32), GT will suddenly end up set without us
// intending to. This can break actual games, so fix it up.
if (bit != CR_GT_BIT)
{
TEST(64, R(RSCRATCH2), R(RSCRATCH2));
FixupBranch dont_clear_gt = J_CC(CC_NZ);
BTS(64, R(RSCRATCH2), Imm8(63));
SetJumpTarget(dont_clear_gt);
}
switch (bit)
{
case CR_SO_BIT: // set bit 61 to input
@ -434,38 +445,35 @@ void Jit64::crXXX(UGeckoInstruction inst)
// instance, if the two CR bits being loaded are the same, two loads are
// not required.
// USES_CR
// crandc or crorc or creqv or crnand or crnor
bool negateA = inst.SUBOP10 == 129 || inst.SUBOP10 == 417 || inst.SUBOP10 == 289 || inst.SUBOP10 == 225 || inst.SUBOP10 == 33;
// crnand or crnor
bool negateB = inst.SUBOP10 == 225 || inst.SUBOP10 == 33;
// creqv or crnand or crnor
bool negateA = inst.SUBOP10 == 289 || inst.SUBOP10 == 225 || inst.SUBOP10 == 33;
// crandc or crorc or crnand or crnor
bool negateB = inst.SUBOP10 == 129 || inst.SUBOP10 == 417 || inst.SUBOP10 == 225 || inst.SUBOP10 == 33;
GetCRFieldBit(inst.CRBA >> 2, 3 - (inst.CRBA & 3), RSCRATCH2, negateA);
GetCRFieldBit(inst.CRBB >> 2, 3 - (inst.CRBB & 3), RSCRATCH, negateB);
GetCRFieldBit(inst.CRBA >> 2, 3 - (inst.CRBA & 3), RSCRATCH, negateA);
GetCRFieldBit(inst.CRBB >> 2, 3 - (inst.CRBB & 3), RSCRATCH2, negateB);
// Compute combined bit
switch (inst.SUBOP10)
{
case 33: // crnor: ~(A || B) == (~A && ~B)
case 129: // crandc
case 257: // crand
case 129: // crandc: A && ~B
case 257: // crand: A && B
AND(8, R(RSCRATCH), R(RSCRATCH2));
break;
case 193: // crxor
case 289: // creqv
case 193: // crxor: A ^ B
case 289: // creqv: ~(A ^ B) = ~A ^ B
XOR(8, R(RSCRATCH), R(RSCRATCH2));
break;
case 225: // crnand: ~(A && B) == (~A || ~B)
case 417: // crorc
case 449: // cror
case 417: // crorc: A || ~B
case 449: // cror: A || B
OR(8, R(RSCRATCH), R(RSCRATCH2));
break;
}
// Store result bit in CRBD
SetCRFieldBit(inst.CRBD >> 2, 3 - (inst.CRBD & 3), RSCRATCH);
gpr.UnlockAllX();
}