Emulator-Archive/ppsspp
1
0
Fork 0
mirror of https://github.com/hrydgard/ppsspp.git synced 2024-11-26 23:10:38 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

initial implementation of vh2f, used in Saint Seiya

Browse Source
This commit is contained in:
Henrik Rydgard 2013-01-13 20:47:40 +01:00
parent 1a5bcc8f06
commit 0a374047b1
1 changed files with 45 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
Core/MIPS/MIPSIntVFPU.cpp
View File

@ -603,28 +603,62 @@ namespace MIPSInt
EatPrefixes();
}
// TODO: CHECK
union FP32 {
u32 u;
float f;
};
struct FP16 {
u16 u;
};
// magic code from ryg: http://fgiesen.wordpress.com/2012/03/28/half-to-float-done-quic/
static FP32 half_to_float_fast5(FP16 h)
{
static const FP32 magic = { (127 + (127 - 15)) << 23 };
static const FP32 was_infnan = { (127 + 16) << 23 };
FP32 o;
o.u = (h.u & 0x7fff) << 13; // exponent/mantissa bits
o.f *= magic.f; // exponent adjust
if (o.f >= was_infnan.f) // make sure Inf/NaN survive
o.u |= 255 << 23;
o.u |= (h.u & 0x8000) << 16; // sign bit
return o;
}
static float ExpandHalf(u16 half) {
FP16 fp16;
fp16.u = half;
FP32 fp = half_to_float_fast5(fp16);
return fp.f;
}
void Int_Vh2f(u32 op)
{
_dbg_assert_msg_(CPU,0,"Trying to interpret instruction that can't be interpreted");
/*
int s[4];
u32 s[4];
float d[4];
int vd = _VD;
int vs = _VS;
int imm = (op >> 16) & 0x1f;
float mult = 1.0f/(float)(1 << imm);
VectorSize sz = GetVecSize(op);
ReadVector((float*)&s, sz, vs);
ApplySwizzleS((float*)&s, sz); //TODO: and the mask to kill everything but swizzle
for (int i = 0; i < GetNumVectorElements(sz); i++)
{
d[i] = (float)s[i] * mult;
VectorSize outsize = V_Pair;
switch (sz) {
case V_Single:
outsize = V_Pair;
d[0] = ExpandHalf(s[0] & 0xFFFF);
d[1] = ExpandHalf(s[0] >> 16);
break;
case V_Pair:
outsize = V_Quad;
d[0] = ExpandHalf(s[0] & 0xFFFF);
d[1] = ExpandHalf(s[0] >> 16);
d[2] = ExpandHalf(s[1] & 0xFFFF);
d[3] = ExpandHalf(s[1] >> 16);
break;
}
ApplyPrefixD(d, sz); //TODO: and the mask to kill everything but mask
WriteVector(d, sz, vd);
*/
PC += 4;
EatPrefixes();
}