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interp: Correct vdet prefix handling.

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2019-02-24 10:41:02 -08:00
parent cc58d0d3a3
commit 01aebe54b9
1 changed files with 14 additions and 10 deletions
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24
Core/MIPS/MIPSIntVFPU.cpp
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@@ -1260,22 +1260,26 @@ namespace MIPSInt
EatPrefixes();
}
void Int_Vdet(MIPSOpcode op)
{
float s[4], t[4];
float d[4];
void Int_Vdet(MIPSOpcode op) {
float s[4]{}, t[4]{}, d[4];
int vd = _VD;
int vs = _VS;
int vt = _VT;
VectorSize sz = GetVecSize(op);
if (sz != V_Pair)
_dbg_assert_msg_(CPU,0,"Trying to interpret instruction that can't be interpreted");
// This is normally V_Pair. Unfilled s/t values are treated as zero.
ReadVector(s, sz, vs);
ApplySwizzleS(s, sz);
ApplySwizzleS(s, V_Quad);
ReadVector(t, sz, vt);
// TODO: The swizzle on t behaves oddly with constants, but sign changes seem to work.
// Also, seems to round in a non-standard way (sometimes toward zero, not always.)
d[0] = s[0] * t[1] - s[1] * t[0];
// T prefix forces swizzle for x and y (yx??.)
// That means negate still works, but constants are a bit weird.
// Note: there is no forced negation here.
u32 tprefixRemove = VFPU_SWIZZLE(3, 3, 0, 0);
u32 tprefixAdd = VFPU_SWIZZLE(1, 0, 0, 0);
ApplyPrefixST(t, VFPURewritePrefix(VFPU_CTRL_TPREFIX, tprefixRemove, tprefixAdd), V_Quad);
d[0] = s[0] * t[0] - s[1] * t[1];
d[0] += s[2] * t[2] + s[3] * t[3];
ApplyPrefixD(d, sz);
WriteVector(d, V_Single, vd);
PC += 4;