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JitArm64: Further optimize NaN handling in ps_sumX 

So short that using farcode is pointless!
This commit is contained in:
JosJuice 2023-08-10 21:34:20 +02:00
parent 8274dcbfe4
commit fc95d59805
1 changed files with 7 additions and 33 deletions
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40
Source/Core/Core/PowerPC/JitArm64/JitArm64_Paired.cpp
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@ -380,42 +380,21 @@ void JitArm64::ps_sumX(UGeckoInstruction inst)
const ARM64Reg VC = fpr.R(c, type); const ARM64Reg VC = fpr.R(c, type);
const ARM64Reg VD = fpr.RW(d, type); const ARM64Reg VD = fpr.RW(d, type);
const ARM64Reg V0 = fpr.GetReg(); const ARM64Reg V0 = fpr.GetReg();
const ARM64Reg temp_gpr = m_accurate_nans && !singles ? gpr.GetReg() : ARM64Reg::INVALID_REG;
m_float_emit.DUP(size, reg_encoder(V0), reg_encoder(VB), 1); m_float_emit.DUP(size, reg_encoder(V0), reg_encoder(VB), 1);
FixupBranch a_nan_done;
if (m_accurate_nans) if (m_accurate_nans)
{ {
// If the first input is NaN, set the temp register for the second input to 0. This is because:
//
// - If the second input is also NaN, setting it to 0 ensures that the first NaN will be picked.
// - If only the first input is NaN, setting the second input to 0 has no effect on the result.
//
// Either way, we can then do an FADD as usual, and the FADD will make the NaN quiet.
m_float_emit.FCMP(scalar_reg_encoder(VA)); m_float_emit.FCMP(scalar_reg_encoder(VA));
FixupBranch a_not_nan = B(CCFlags::CC_VC); FixupBranch a_not_nan = B(CCFlags::CC_VC);
FixupBranch a_nan = B(); m_float_emit.MOVI(64, scalar_reg_encoder(V0), 0);
SetJumpTarget(a_not_nan); SetJumpTarget(a_not_nan);
SwitchToFarCode();
SetJumpTarget(a_nan);
if (upper)
{
m_float_emit.FADD(scalar_reg_encoder(V0), scalar_reg_encoder(VA), scalar_reg_encoder(VA));
m_float_emit.TRN1(size, reg_encoder(VD), reg_encoder(VC), reg_encoder(V0));
}
else if (d != c)
{
m_float_emit.FADD(scalar_reg_encoder(VD), scalar_reg_encoder(VA), scalar_reg_encoder(VA));
m_float_emit.INS(size, VD, 1, VC, 1);
}
else
{
m_float_emit.FADD(scalar_reg_encoder(V0), scalar_reg_encoder(VA), scalar_reg_encoder(VA));
m_float_emit.INS(size, VD, 0, V0, 0);
}
FixupBranch a_nan_done = B();
SwitchToNearCode();
// If exactly one input is NaN, AArch64 arithmetic instructions automatically pick that NaN
// and make it quiet, just like we want. So if rA isn't NaN, we can skip checking rB.
} }
if (upper) if (upper)
@ -434,12 +413,7 @@ void JitArm64::ps_sumX(UGeckoInstruction inst)
m_float_emit.INS(size, VD, 0, V0, 0); m_float_emit.INS(size, VD, 0, V0, 0);
} }
if (m_accurate_nans)
SetJumpTarget(a_nan_done);
fpr.Unlock(V0); fpr.Unlock(V0);
if (temp_gpr != ARM64Reg::INVALID_REG)
gpr.Unlock(temp_gpr);
ASSERT_MSG(DYNA_REC, singles == (fpr.IsSingle(a) && fpr.IsSingle(b) && fpr.IsSingle(c)), ASSERT_MSG(DYNA_REC, singles == (fpr.IsSingle(a) && fpr.IsSingle(b) && fpr.IsSingle(c)),
"Register allocation turned singles into doubles in the middle of ps_sumX"); "Register allocation turned singles into doubles in the middle of ps_sumX");