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[X86] AVX512: Simplify logic in isCDisp8 

It was computing the VL/n case as:
  MemObjSize = VectorByteSize / ElemByteSize / Divider * ElemByteSize

ElemByteSize not only falls out but VectorByteSize/Divider now actually
matches the definition of VL/n.

Also some formatting fixes.

llvm-svn: 212794
This commit is contained in:
Adam Nemet 2014-07-11 05:23:12 +00:00
parent de1e1a60e8
commit e311c3c836
1 changed files with 6 additions and 6 deletions
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12
llvm/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
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@ -185,7 +185,8 @@ static bool isDisp8(int Value) {
/// isCDisp8 - Return true if this signed displacement fits in a 8-bit
/// compressed dispacement field.
static bool isCDisp8(uint64_t TSFlags, int Value, int& CValue) {
assert((TSFlags & X86II::EncodingMask) >> X86II::EncodingShift == X86II::EVEX &&
assert(((TSFlags & X86II::EncodingMask) >>
X86II::EncodingShift == X86II::EVEX) &&
"Compressed 8-bit displacement is only valid for EVEX inst.");
unsigned CD8E = (TSFlags >> X86II::EVEX_CD8EShift) & X86II::EVEX_CD8EMask;
@ -195,7 +196,7 @@ static bool isCDisp8(uint64_t TSFlags, int Value, int& CValue) {
CValue = Value;
return isDisp8(Value);
}
unsigned MemObjSize = 1U << CD8E;
if (CD8V & 4) {
// Fixed vector length
@ -208,10 +209,9 @@ static bool isCDisp8(uint64_t TSFlags, int Value, int& CValue) {
EVEX_LL += ((TSFlags >> X86II::VEXShift) & X86II::EVEX_L2) ? 2 : 0;
assert(EVEX_LL < 3 && "");
unsigned NumElems = (1U << (EVEX_LL + 4)) / MemObjSize;
NumElems /= 1U << (CD8V & 0x3);
MemObjSize *= NumElems;
unsigned VectorByteSize = 1U << (EVEX_LL + 4);
unsigned Divider = 1U << (CD8V & 0x3);
MemObjSize = VectorByteSize / Divider;
}
}