sanchayanmaity/gem5
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

X86: Create a pack media microop.

Browse source
This commit is contained in:
Gabe Black 2009-08-17 18:27:54 -07:00
parent e6b5192c26
commit 1273277d3b
1 changed files with 67 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

67
src/arch/x86/isa/microops/mediaop.isa
View file

@ -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)