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X86: Implement a media microop for converting integer values to floating point.

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Gabe Black 2009-08-17 18:41:25 -07:00
parent b34b507fd8
commit 8e97cd9c8f
1 changed files with 60 additions and 0 deletions
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60
src/arch/x86/isa/microops/mediaop.isa
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@ -758,4 +758,64 @@ let {{
}
FpDestReg.uqw = result;
'''
class Cvti2f(MediaOp):
def __init__(self, dest, src, \
size = None, destSize = None, srcSize = None, ext = None):
super(Cvti2f, self).__init__(dest, src,\
"InstRegIndex(0)", size, destSize, srcSize, ext)
code = '''
union floatInt
{
float f;
uint32_t i;
};
union doubleInt
{
double d;
uint64_t i;
};
assert(destSize == 4 || destSize == 8);
assert(srcSize == 4 || srcSize == 8);
int srcSizeBits = srcSize * 8;
int destSizeBits = destSize * 8;
int items;
int srcStart = 0;
int destStart = 0;
if (srcSize == 2 * destSize) {
items = (ext & 0x1) ? 1: sizeof(FloatRegBits) / srcSize;
if (ext & 0x2)
destStart = destSizeBits * items;
} else if (destSize == 2 * srcSize) {
items = (ext & 0x1) ? 1: sizeof(FloatRegBits) / destSize;
if (ext & 0x2)
srcStart = srcSizeBits * items;
} else {
items = (ext & 0x1) ? 1: sizeof(FloatRegBits) / destSize;
}
uint64_t result = FpDestReg.uqw;
for (int i = 0; i < items; i++) {
int srcHiIndex = srcStart + (i + 1) * srcSizeBits - 1;
int srcLoIndex = srcStart + (i + 0) * srcSizeBits;
uint64_t argBits = bits(FpSrcReg1.uqw, srcHiIndex, srcLoIndex);
int64_t sArg = argBits | (0 - (argBits & (1 << srcHiIndex)));
double arg = sArg;
if (destSize == 4) {
floatInt fi;
fi.f = arg;
argBits = fi.i;
} else {
doubleInt di;
di.d = arg;
argBits = di.i;
}
int destHiIndex = destStart + (i + 1) * destSizeBits - 1;
int destLoIndex = destStart + (i + 0) * destSizeBits;
result = insertBits(result, destHiIndex, destLoIndex, argBits);
}
FpDestReg.uqw = result;
'''
}};