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| author | Gabe Black <gblack@eecs.umich.edu> | 2009-08-17 18:27:54 -0700 |
|---|---|---|
| committer | Gabe Black <gblack@eecs.umich.edu> | 2009-08-17 18:27:54 -0700 |
| commit | 1273277d3be26fa40ceaddd3d0a137496d098914 (patch) | |
| tree | 4c4613cfb325969004b5f311768b64fc77e2d73e /src | |
| parent | e6b5192c2601d15a5f34b13ce2a83392575f90e7 (diff) | |
| download | gem5-1273277d3be26fa40ceaddd3d0a137496d098914.tar.xz | |
X86: Create a pack media microop.
Diffstat (limited to 'src')
| -rw-r--r-- | src/arch/x86/isa/microops/mediaop.isa | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/src/arch/x86/isa/microops/mediaop.isa b/src/arch/x86/isa/microops/mediaop.isa index 048a856f9..fe7a84511 100644 --- a/src/arch/x86/isa/microops/mediaop.isa +++ b/src/arch/x86/isa/microops/mediaop.isa @@ -335,6 +335,73 @@ let {{ FpDestReg.uqw = result; ''' + class Pack(MediaOp): + code = ''' + assert(srcSize == destSize * 2); + int items = (sizeof(FloatRegBits) / destSize); + int destBits = destSize * 8; + int srcBits = srcSize * 8; + uint64_t result = 0; + int i; + for (i = 0; i < items / 2; i++) { + uint64_t picked = + bits(FpSrcReg1.uqw, (i + 1) * srcBits - 1, + (i + 0) * srcBits); + unsigned signBit = bits(picked, srcBits - 1); + uint64_t overflow = bits(picked, srcBits - 1, destBits - 1); + + // Handle saturation. + if (signBit) { + if (overflow != mask(destBits - srcBits + 1)) { + if (ext & 0x1) + picked = (1 << (destBits - 1)); + else + picked = 0; + } + } else { + if (overflow != 0) { + if (ext & 0x1) + picked = mask(destBits - 1); + else + picked = mask(destBits); + } + } + result = insertBits(result, + (i + 1) * destBits - 1, + (i + 0) * destBits, + picked); + } + for (;i < items; i++) { + uint64_t picked = + bits(FpSrcReg2.uqw, (i - items + 1) * srcBits - 1, + (i - items + 0) * srcBits); + unsigned signBit = bits(picked, srcBits - 1); + uint64_t overflow = bits(picked, srcBits - 1, destBits - 1); + + // Handle saturation. + if (signBit) { + if (overflow != mask(destBits - srcBits + 1)) { + if (ext & 0x1) + picked = (1 << (destBits - 1)); + else + picked = 0; + } + } else { + if (overflow != 0) { + if (ext & 0x1) + picked = mask(destBits - 1); + else + picked = mask(destBits); + } + } + result = insertBits(result, + (i + 1) * destBits - 1, + (i + 0) * destBits, + picked); + } + FpDestReg.uqw = result; + ''' + class Mxor(MediaOp): def __init__(self, dest, src1, src2): super(Mxor, self).__init__(dest, src1, src2, 1) |