JitArm64: no intermediate rounding for paired FMA

This commit is contained in:
Tillmann Karras 2020-06-13 07:11:10 +01:00
parent 2a46c1f86f
commit a04ac23794
1 changed files with 118 additions and 21 deletions

View File

@ -53,7 +53,7 @@ void JitArm64::ps_mergeXX(UGeckoInstruction inst)
ARM64Reg V0 = fpr.GetReg();
m_float_emit.INS(size, V0, 0, VA, 1);
m_float_emit.INS(size, V0, 1, VB, 0);
m_float_emit.ORR(reg_encoder(VD), reg_encoder(V0), reg_encoder(V0));
m_float_emit.MOV(reg_encoder(VD), reg_encoder(V0));
fpr.Unlock(V0);
}
break;
@ -110,38 +110,134 @@ void JitArm64::ps_maddXX(UGeckoInstruction inst)
ARM64Reg VB = reg_encoder(fpr.R(b, type));
ARM64Reg VC = reg_encoder(fpr.R(c, type));
ARM64Reg VD = reg_encoder(fpr.RW(d, type));
ARM64Reg V0Q = fpr.GetReg();
ARM64Reg V0 = reg_encoder(V0Q);
// TODO: Do FMUL and FADD/FSUB in *one* host call to save accuracy.
ARM64Reg V0Q = INVALID_REG;
ARM64Reg V0 = INVALID_REG;
if (d != b && (d == a || d == c))
{
V0Q = fpr.GetReg();
V0 = reg_encoder(V0Q);
}
switch (op5)
{
case 14: // ps_madds0
m_float_emit.FMUL(size, V0, VA, VC, 0);
m_float_emit.FADD(size, VD, V0, VB);
// d = a * c.ps0 + b
if (d == b)
{
m_float_emit.FMLA(size, VD, VA, VC, 0);
}
else if (d != a && d != c)
{
m_float_emit.MOV(VD, VB);
m_float_emit.FMLA(size, VD, VA, VC, 0);
}
else
{
m_float_emit.MOV(V0, VB);
m_float_emit.FMLA(size, V0, VA, VC, 0);
m_float_emit.MOV(VD, V0);
}
break;
case 15: // ps_madds1
m_float_emit.FMUL(size, V0, VA, VC, 1);
m_float_emit.FADD(size, VD, V0, VB);
// d = a * c.ps1 + b
if (d == b)
{
m_float_emit.FMLA(size, VD, VA, VC, 1);
}
else if (d != a && d != c)
{
m_float_emit.MOV(VD, VB);
m_float_emit.FMLA(size, VD, VA, VC, 1);
}
else
{
m_float_emit.MOV(V0, VB);
m_float_emit.FMLA(size, V0, VA, VC, 1);
m_float_emit.MOV(VD, V0);
}
break;
case 28: // ps_msub
m_float_emit.FMUL(size, V0, VA, VC);
m_float_emit.FSUB(size, VD, V0, VB);
// d = a * c - b
if (d == b)
{
// d = -(-a * c + b)
// rounding is incorrect if the rounding mode is +/- infinity
m_float_emit.FMLS(size, VD, VB, VC);
m_float_emit.FNEG(size, VD, VD);
}
else if (d != a && d != c)
{
m_float_emit.FNEG(size, VD, VB);
m_float_emit.FMLA(size, VD, VA, VC);
}
else
{
m_float_emit.FNEG(size, V0, VB);
m_float_emit.FMLA(size, V0, VA, VC);
m_float_emit.MOV(VD, V0);
}
break;
case 29: // ps_madd
m_float_emit.FMUL(size, V0, VA, VC);
m_float_emit.FADD(size, VD, V0, VB);
// d = a * c + b
if (d == b)
{
m_float_emit.FMLA(size, VD, VA, VC);
}
else if (d != a && d != c)
{
m_float_emit.MOV(VD, VB);
m_float_emit.FMLA(size, VD, VA, VC);
}
else
{
m_float_emit.MOV(V0, VB);
m_float_emit.FMLA(size, V0, VA, VC);
m_float_emit.MOV(VD, V0);
}
break;
case 30: // ps_nmsub
m_float_emit.FMUL(size, V0, VA, VC);
m_float_emit.FSUB(size, VD, V0, VB);
m_float_emit.FNEG(size, VD, VD);
// d = -(a * c - b)
// =>
// d = -a * c + b
// Note: PowerPC rounds before the final negation.
// We don't handle this at the moment because it's
// only relevant when rounding to +/- infinity.
if (d == b)
{
m_float_emit.FMLS(size, VD, VA, VC);
}
else if (d != a && d != c)
{
m_float_emit.MOV(VD, VB);
m_float_emit.FMLS(size, VD, VA, VC);
}
else
{
m_float_emit.MOV(V0, VB);
m_float_emit.FMLS(size, V0, VA, VC);
m_float_emit.MOV(VD, V0);
}
break;
case 31: // ps_nmadd
m_float_emit.FMUL(size, V0, VA, VC);
m_float_emit.FADD(size, VD, V0, VB);
m_float_emit.FNEG(size, VD, VD);
// d = -(a * c + b)
if (d == b)
{
m_float_emit.FMLA(size, VD, VA, VC);
m_float_emit.FNEG(size, VD, VD);
}
else if (d != a && d != c)
{
// d = -a * c - b
// See rounding note at ps_nmsub.
m_float_emit.FNEG(size, VD, VB);
m_float_emit.FMLS(size, VD, VA, VC);
}
else
{
m_float_emit.MOV(V0, VB);
m_float_emit.FMLA(size, V0, VA, VC);
m_float_emit.FNEG(size, VD, V0);
}
break;
default:
ASSERT_MSG(DYNA_REC, 0, "ps_madd - invalid op");
@ -149,7 +245,8 @@ void JitArm64::ps_maddXX(UGeckoInstruction inst)
}
fpr.FixSinglePrecision(d);
fpr.Unlock(V0Q);
if (V0Q != INVALID_REG)
fpr.Unlock(V0Q);
}
void JitArm64::ps_sel(UGeckoInstruction inst)
@ -181,7 +278,7 @@ void JitArm64::ps_sel(UGeckoInstruction inst)
ARM64Reg V0 = reg_encoder(V0Q);
m_float_emit.FCMGE(size, V0, VA);
m_float_emit.BSL(V0, VC, VB);
m_float_emit.ORR(VD, V0, V0);
m_float_emit.MOV(VD, V0);
fpr.Unlock(V0Q);
}
}