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

ARM: Add a function to decode SIMD modified immediate constants.

Browse source
This commit is contained in:
Gabe Black 2010-06-02 12:58:12 -05:00
parent abda50173c
commit 7eb4d02dd9
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/arm/insts/pred_inst.hh
View file

@ -77,6 +77,73 @@ modified_imm(uint8_t ctrlImm, uint8_t dataImm)
return bigData << (32 - bigCtrl);
}
static inline uint64_t
simd_modified_imm(bool op, uint8_t cmode, uint8_t data)
{
uint64_t bigData = data;
switch (cmode) {
case 0x0:
case 0x1:
bigData = (bigData << 0) | (bigData << 32);
break;
case 0x2:
case 0x3:
bigData = (bigData << 8) | (bigData << 40);
break;
case 0x4:
case 0x5:
bigData = (bigData << 16) | (bigData << 48);
break;
case 0x6:
case 0x7:
bigData = (bigData << 24) | (bigData << 56);
break;
case 0x8:
case 0x9:
bigData = (bigData << 0) | (bigData << 16) |
(bigData << 32) | (bigData << 48);
break;
case 0xa:
case 0xb:
bigData = (bigData << 8) | (bigData << 24) |
(bigData << 40) | (bigData << 56);
break;
case 0xc:
bigData = (0xffULL << 0) | (bigData << 8) |
(0xffULL << 32) | (bigData << 40);
break;
case 0xd:
bigData = (0xffffULL << 0) | (bigData << 16) |
(0xffffULL << 32) | (bigData << 48);
break;
case 0xe:
if (op) {
bigData = (bigData << 0) | (bigData << 8) |
(bigData << 16) | (bigData << 24) |
(bigData << 32) | (bigData << 40) |
(bigData << 48) | (bigData << 56);
} else {
bigData = 0;
for (int i = 7; i >= 0; i--) {
if (bits(data, i)) {
bigData |= (0xFF << (i * 8));
}
}
}
case 0xf:
if (!op) {
uint64_t bVal = bits(bigData, 6) ? (0x1F) : (0x20);
bigData = (bits(bigData, 5, 0) << 19) |
(bVal << 25) | (bits(bigData, 7) << 31);
bigData |= (bigData << 32);
}
// Fall through
default:
panic("Illegal modified SIMD immediate parameters.\n");
}
return bigData;
}
/**
* Base class for predicated integer operations.