[Beignet] [PATCH V3] backend: refine load store optimization
rander.wang
rander.wang at intel.com
Fri Jul 7 02:53:22 UTC 2017
this fix basic test in conformance tests failed for vec8 of char because
of overflow. And it fix many test items failed in opencv because of
offset error
(1)modify the size of searchInsnArray to 32, it is the max size for char
And add check for overflow if too many insn
(2)Make sure the start insn is the first insn of searched array
because if it is not the first, the offset maybe invalid. And
it is complex to modify offset without error
V2:refine search index, using J not I
V3:remove (2), now add offset to the pointer of start
pass OpenCV, conformance basic and compiler tests, utests
Signed-off-by: rander.wang <rander.wang at intel.com>
---
backend/src/llvm/llvm_loadstore_optimization.cpp | 103 ++++++++++++++++-------
1 file changed, 74 insertions(+), 29 deletions(-)
diff --git a/backend/src/llvm/llvm_loadstore_optimization.cpp b/backend/src/llvm/llvm_loadstore_optimization.cpp
index c91c1a0..081f16e 100644
--- a/backend/src/llvm/llvm_loadstore_optimization.cpp
+++ b/backend/src/llvm/llvm_loadstore_optimization.cpp
@@ -68,13 +68,14 @@ namespace gbe {
bool optimizeLoadStore(BasicBlock &BB);
bool isLoadStoreCompatible(Value *A, Value *B, int *dist, int* elementSize, int maxVecSize);
- void mergeLoad(BasicBlock &BB, SmallVector<Instruction*, 16> &merged);
- void mergeStore(BasicBlock &BB, SmallVector<Instruction*, 16> &merged);
+ void mergeLoad(BasicBlock &BB, SmallVector<Instruction*, 16> &merged, Instruction *start,int offset);
+ void mergeStore(BasicBlock &BB, SmallVector<Instruction*, 16> &merged, Instruction *start,int offset);
bool findConsecutiveAccess(BasicBlock &BB,
SmallVector<Instruction*, 16> &merged,
const BasicBlock::iterator &start,
unsigned maxVecSize,
- bool isLoad);
+ bool isLoad,
+ int *addrOffset);
#if LLVM_VERSION_MAJOR * 10 + LLVM_VERSION_MINOR >= 40
virtual StringRef getPassName() const
#else
@@ -143,7 +144,10 @@ namespace gbe {
return (abs(-offset) < sz*maxVecSize);
}
- void GenLoadStoreOptimization::mergeLoad(BasicBlock &BB, SmallVector<Instruction*, 16> &merged) {
+ void GenLoadStoreOptimization::mergeLoad(BasicBlock &BB,
+ SmallVector<Instruction*, 16> &merged,
+ Instruction *start,
+ int offset) {
IRBuilder<> Builder(&BB);
unsigned size = merged.size();
@@ -151,14 +155,24 @@ namespace gbe {
for(unsigned i = 0; i < size; i++) {
values.push_back(merged[i]);
}
- LoadInst *ld = cast<LoadInst>(merged[0]);
+ LoadInst *ld = cast<LoadInst>(start);
unsigned align = ld->getAlignment();
unsigned addrSpace = ld->getPointerAddressSpace();
// insert before first load
Builder.SetInsertPoint(ld);
+
+ //modify offset
+ Value *newPtr = ld->getPointerOperand();
+ if(offset != 0)
+ {
+ Value *StartAddr = Builder.CreatePtrToInt(ld->getPointerOperand(), Builder.getInt32Ty());
+ Value *offsetVal = ConstantInt::get(Builder.getInt32Ty(), offset);
+ Value *newAddr = Builder.CreateAdd(StartAddr, offsetVal);
+ newPtr = Builder.CreateIntToPtr(newAddr, ld->getPointerOperand()->getType());
+ }
+
VectorType *vecTy = VectorType::get(ld->getType(), size);
- Value *vecPtr = Builder.CreateBitCast(ld->getPointerOperand(),
- PointerType::get(vecTy, addrSpace));
+ Value *vecPtr = Builder.CreateBitCast(newPtr, PointerType::get(vecTy, addrSpace));
LoadInst *vecValue = Builder.CreateLoad(vecPtr);
vecValue->setAlignment(align);
@@ -196,8 +210,8 @@ namespace gbe {
SmallVector<Instruction*, 16> &merged,
const BasicBlock::iterator &start,
unsigned maxVecSize,
- bool isLoad) {
-
+ bool isLoad,
+ int *addrOffset) {
if(!isSimpleLoadStore(&*start)) return false;
unsigned targetAddrSpace = getAddressSpace(&*start);
@@ -212,23 +226,26 @@ namespace gbe {
bool ready = false;
int elementSize;
- SmallVector<mergedInfo *, 16> searchInsnArray;
- mergedInfo meInfoArray[16];
+ SmallVector<mergedInfo *, 32> searchInsnArray;
+ mergedInfo meInfoArray[32];
int indx = 0;
meInfoArray[indx++].init(&*start, 0);
-
searchInsnArray.push_back(&meInfoArray[0]);
- BasicBlock::iterator I = start;
- ++I;
- for(unsigned ss = 0; I!= E && ss <= maxLimit; ++ss, ++I) {
- if((isLoad && isa<LoadInst>(*I)) || (!isLoad && isa<StoreInst>(*J))) {
+ bool realReorder = false;
+ for(unsigned ss = 0; J!= E && ss <= maxLimit; ++ss, ++J) {
+ if((isLoad && isa<LoadInst>(*J)) || (!isLoad && isa<StoreInst>(*J))) {
int distance;
- if(isLoadStoreCompatible(searchInsnArray[0]->mInsn, &*I, &distance, &elementSize, maxVecSize))
+ if(isLoadStoreCompatible(searchInsnArray[0]->mInsn, &*J, &distance, &elementSize, maxVecSize))
{
- meInfoArray[indx].init(&*I, distance);
+ meInfoArray[indx].init(&*J, distance);
searchInsnArray.push_back(&meInfoArray[indx]);
indx++;
+ if(indx >= 32)
+ break;
+
+ if(reordered)
+ realReorder = true;
}
} else if((isLoad && isa<StoreInst>(*J))) {
// simple stop to keep read/write order
@@ -248,10 +265,11 @@ namespace gbe {
break;
}
}
-
- if(merged.size() >= maxVecSize) break;
}
+ if(!realReorder)
+ reordered = false;
+
if(indx > 1)
{
//try to sort the load/store by the offset from the start
@@ -275,8 +293,16 @@ namespace gbe {
if(j > 0 && ready)
{
- for(unsigned k = 0; k < j+1; k++)
+ unsigned endIndx = j + 1;
+ *addrOffset = searchInsnArray[i]->mOffset;
+ endIndx = (endIndx >= 16) ? 16 : (endIndx >= 8 ? 8 : (endIndx >= 4 ? 4 : endIndx));
+
+ for(unsigned k = 0; k < endIndx; k++)
+ {
merged.push_back(searchInsnArray[i+k]->mInsn);
+ if (k >= maxVecSize)
+ break;
+ }
break;
}
@@ -286,7 +312,10 @@ namespace gbe {
return reordered;
}
- void GenLoadStoreOptimization::mergeStore(BasicBlock &BB, SmallVector<Instruction*, 16> &merged) {
+ void GenLoadStoreOptimization::mergeStore(BasicBlock &BB,
+ SmallVector<Instruction*, 16> &merged,
+ Instruction *start,
+ int offset) {
IRBuilder<> Builder(&BB);
unsigned size = merged.size();
@@ -294,7 +323,7 @@ namespace gbe {
for(unsigned i = 0; i < size; i++) {
values.push_back(cast<StoreInst>(merged[i])->getValueOperand());
}
- StoreInst *st = cast<StoreInst>(merged[0]);
+ StoreInst *st = cast<StoreInst>(start);
if(!st)
return;
@@ -314,7 +343,18 @@ namespace gbe {
Value * stPointer = st->getPointerOperand();
if(!stPointer)
return;
- Value *newPtr = Builder.CreateBitCast(stPointer, PointerType::get(vecTy, addrSpace));
+
+ //modify offset
+ Value *newSPtr = stPointer;
+ if(offset != 0)
+ {
+ Value *StartAddr = Builder.CreatePtrToInt(stPointer, Builder.getInt32Ty());
+ Value *offsetVal = ConstantInt::get(Builder.getInt32Ty(), offset);
+ Value *newAddr = Builder.CreateAdd(StartAddr, offsetVal);
+ newSPtr = Builder.CreateIntToPtr(newAddr, stPointer->getType());
+ }
+
+ Value *newPtr = Builder.CreateBitCast(newSPtr, PointerType::get(vecTy, addrSpace));
StoreInst *newST = Builder.CreateStore(parent, newPtr);
newST->setAlignment(align);
}
@@ -330,10 +370,13 @@ namespace gbe {
unsigned size = toBeDeleted.size();
if (reorder) {
unsigned i = 0;
- while (i < size && toBeDeleted[i] == &*safe) {
- ++i;
+ while (i < size) {
+ if(toBeDeleted[i] == &*safe) {
++safe;
}
+
+ ++i;
+ }
} else {
safe = BasicBlock::iterator(toBeDeleted[size - 1]);
++safe;
@@ -355,12 +398,14 @@ namespace gbe {
((ty->isIntegerTy(8) || ty->isIntegerTy(16)) && isLoad)))
continue;
+ int addrOffset = 0;
unsigned maxVecSize = (ty->isFloatTy() || ty->isIntegerTy(32)) ? 4 :
(ty->isIntegerTy(16) ? 8 : 16);
- bool reorder = findConsecutiveAccess(BB, merged, BBI, maxVecSize, isLoad);
+ bool reorder = findConsecutiveAccess(BB, merged, BBI, maxVecSize, isLoad, &addrOffset);
uint32_t size = merged.size();
uint32_t pos = 0;
bool doDeleting = size > 1;
+ BasicBlock::iterator startLS = BBI;
if (doDeleting) {
// choose next undeleted instruction
BBI = findSafeInstruction(merged, BBI, reorder);
@@ -372,9 +417,9 @@ namespace gbe {
(size >= 4 ? 4 : size));
SmallVector<Instruction*, 16> mergedVec(merged.begin() + pos, merged.begin() + pos + vecSize);
if(isLoad)
- mergeLoad(BB, mergedVec);
+ mergeLoad(BB, mergedVec, &*startLS, addrOffset);
else
- mergeStore(BB, mergedVec);
+ mergeStore(BB, mergedVec, &*startLS, addrOffset);
// remove merged insn
for(uint32_t i = 0; i < mergedVec.size(); i++)
mergedVec[i]->eraseFromParent();
--
2.7.4
More information about the Beignet
mailing list