Files
triton/lib/Conversion/TritonGPUToLLVM/LoadStoreOpToLLVM.cpp

885 lines
35 KiB
C++

#include "mlir/IR/Matchers.h"
#include "mlir/IR/TypeUtilities.h"
#include "ConvertLayoutOpToLLVM.h"
#include "LoadStoreOpToLLVM.h"
using namespace mlir;
using namespace mlir::triton;
using ::mlir::LLVM::getElementsFromStruct;
using ::mlir::LLVM::getSharedMemoryObjectFromStruct;
using ::mlir::LLVM::getStructFromElements;
using ::mlir::triton::gpu::getElemsPerThread;
using ::mlir::triton::gpu::SharedEncodingAttr;
// Contains some helper functions for both Load and Store conversions.
struct LoadStoreConversionBase {
explicit LoadStoreConversionBase(AxisInfoAnalysis &axisAnalysisPass)
: axisAnalysisPass(axisAnalysisPass) {}
// Get corresponding LLVM element values of \param value.
static SmallVector<Value> getLLVMElems(Value value, Value llValue,
ConversionPatternRewriter &rewriter,
Location loc) {
if (!value)
return {};
if (!llValue.getType().isa<LLVM::LLVMStructType>())
return {llValue};
// Here, we assume that all inputs should have a blockedLayout
auto valueVals = getElementsFromStruct(loc, llValue, rewriter);
return valueVals;
}
unsigned getVectorSize(Value ptr) const {
return axisAnalysisPass.getPtrVectorSize(ptr);
}
unsigned getMaskAlignment(Value mask) const {
return axisAnalysisPass.getMaskAlignment(mask);
}
protected:
AxisInfoAnalysis &axisAnalysisPass;
};
struct LoadOpConversion
: public ConvertTritonGPUOpToLLVMPattern<triton::LoadOp>,
public LoadStoreConversionBase {
using ConvertTritonGPUOpToLLVMPattern<
triton::LoadOp>::ConvertTritonGPUOpToLLVMPattern;
LoadOpConversion(LLVMTypeConverter &converter,
AxisInfoAnalysis &axisAnalysisPass, PatternBenefit benefit)
: ConvertTritonGPUOpToLLVMPattern<triton::LoadOp>(converter, benefit),
LoadStoreConversionBase(axisAnalysisPass) {}
LogicalResult
matchAndRewrite(triton::LoadOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
auto loc = op->getLoc();
// original values
Value ptr = op.ptr();
Value mask = op.mask();
Value other = op.other();
// adaptor values
Value llPtr = adaptor.ptr();
Value llMask = adaptor.mask();
Value llOther = adaptor.other();
// Determine the vectorization size
Type valueTy = op.getResult().getType();
Type valueElemTy =
typeConverter->convertType(getElementTypeOrSelf(valueTy));
unsigned vec = getVectorSize(ptr);
unsigned numElems = getElemsPerThread(ptr.getType());
if (llMask)
vec = std::min<size_t>(vec, getMaskAlignment(mask));
// Get the LLVM values for pointers
auto ptrElems = getLLVMElems(ptr, llPtr, rewriter, loc);
assert(ptrElems.size() == numElems);
// Get the LLVM values for mask
SmallVector<Value> maskElems;
if (llMask) {
maskElems = getLLVMElems(mask, llMask, rewriter, loc);
assert(maskElems.size() == numElems);
}
// Get the LLVM values for `other`
// TODO: (goostavz) handle when other is const but not splat, which
// should be rarely seen
bool otherIsSplatConstInt = false;
DenseElementsAttr constAttr;
int64_t splatVal = 0;
if (other && valueElemTy.isa<IntegerType>() &&
matchPattern(other, m_Constant(&constAttr)) && constAttr.isSplat()) {
otherIsSplatConstInt = true;
splatVal = constAttr.getSplatValue<APInt>().getSExtValue();
}
auto otherElems = getLLVMElems(other, llOther, rewriter, loc);
// vectorized iteration through all the pointer/mask/other elements
const int valueElemNbits =
std::max(8u, valueElemTy.getIntOrFloatBitWidth());
const int numVecs = numElems / vec;
SmallVector<Value> loadedVals;
for (size_t vecStart = 0; vecStart < numElems; vecStart += vec) {
// TODO: optimization when ptr is GEP with constant offset
size_t in_off = 0;
const size_t maxWordWidth = std::max<size_t>(32, valueElemNbits);
const size_t totalWidth = valueElemNbits * vec;
const size_t width = std::min(totalWidth, maxWordWidth);
const size_t nWords = std::max<size_t>(1, totalWidth / width);
const size_t wordNElems = width / valueElemNbits;
assert(wordNElems * nWords * numVecs == numElems);
// TODO(Superjomn) Add cache policy fields to StoreOp.
// TODO(Superjomn) Deal with cache policy here.
const bool hasL2EvictPolicy = false;
PTXBuilder ptxBuilder;
Value pred = mask ? maskElems[vecStart] : int_val(1, 1);
const std::string readConstraint =
(width == 64) ? "l" : ((width == 32) ? "r" : "c");
const std::string writeConstraint =
(width == 64) ? "=l" : ((width == 32) ? "=r" : "=c");
// prepare asm operands
auto *dstsOpr = ptxBuilder.newListOperand();
for (size_t wordIdx = 0; wordIdx < nWords; ++wordIdx) {
auto *opr = ptxBuilder.newOperand(writeConstraint); // =r operations
dstsOpr->listAppend(opr);
}
auto *addrOpr =
ptxBuilder.newAddrOperand(ptrElems[vecStart], "l", in_off);
// Define the instruction opcode
auto &ld = ptxBuilder.create<>("ld")
->o("volatile", op.isVolatile())
.global()
.o("ca", op.cache() == triton::CacheModifier::CA)
.o("cg", op.cache() == triton::CacheModifier::CG)
.o("L1::evict_first",
op.evict() == triton::EvictionPolicy::EVICT_FIRST)
.o("L1::evict_last",
op.evict() == triton::EvictionPolicy::EVICT_LAST)
.o("L1::cache_hint", hasL2EvictPolicy)
.v(nWords)
.b(width);
PTXBuilder::Operand *evictOpr{};
// Here lack a mlir::Value to bind to this operation, so disabled.
// if (has_l2_evict_policy)
// evictOpr = ptxBuilder.newOperand(l2Evict, "l");
if (!evictOpr)
ld(dstsOpr, addrOpr).predicate(pred, "b");
else
ld(dstsOpr, addrOpr, evictOpr).predicate(pred, "b");
if (other) {
for (size_t ii = 0; ii < nWords; ++ii) {
// PTX doesn't support mov.u8, so we need to use mov.u16
auto movWidth = width < 16 ? 16 : width;
PTXInstr &mov =
ptxBuilder.create<>("mov")->o("u" + std::to_string(movWidth));
size_t size = width / valueElemNbits;
auto vecTy = LLVM::getFixedVectorType(valueElemTy, size);
Value v = undef(vecTy);
for (size_t s = 0; s < size; ++s) {
Value falseVal = otherElems[vecStart + ii * size + s];
Value sVal = createIndexAttrConstant(
rewriter, loc, this->getTypeConverter()->getIndexType(), s);
v = insert_element(vecTy, v, falseVal, sVal);
}
v = bitcast(v, IntegerType::get(getContext(), width));
PTXInstr::Operand *opr{};
if (otherIsSplatConstInt)
opr = ptxBuilder.newConstantOperand(splatVal);
else
opr = ptxBuilder.newOperand(v, readConstraint);
mov(dstsOpr->listGet(ii), opr).predicateNot(pred, "b");
}
}
// Create inline ASM signature
SmallVector<Type> retTys(nWords, IntegerType::get(getContext(), width));
Type retTy = retTys.size() > 1
? LLVM::LLVMStructType::getLiteral(getContext(), retTys)
: retTys[0];
// TODO: if (has_l2_evict_policy)
// auto asmDialectAttr =
// LLVM::AsmDialectAttr::get(rewriter.getContext(),
// LLVM::AsmDialect::AD_ATT);
Value ret = ptxBuilder.launch(rewriter, loc, retTy);
// Extract and store return values
SmallVector<Value> rets;
for (unsigned int ii = 0; ii < nWords; ++ii) {
Value curr;
if (retTy.isa<LLVM::LLVMStructType>()) {
curr = extract_val(IntegerType::get(getContext(), width), ret,
rewriter.getI64ArrayAttr(ii));
} else {
curr = ret;
}
curr = bitcast(curr, LLVM::getFixedVectorType(valueElemTy,
width / valueElemNbits));
rets.push_back(curr);
}
int tmp = width / valueElemNbits;
for (size_t ii = 0; ii < vec; ++ii) {
Value vecIdx = createIndexAttrConstant(
rewriter, loc, this->getTypeConverter()->getIndexType(), ii % tmp);
Value loaded = extract_element(valueElemTy, rets[ii / tmp], vecIdx);
loadedVals.push_back(loaded);
}
} // end vec
Type llvmResultStructTy = getTypeConverter()->convertType(valueTy);
Value resultStruct =
getStructFromElements(loc, loadedVals, rewriter, llvmResultStructTy);
rewriter.replaceOp(op, {resultStruct});
return success();
}
};
struct StoreOpConversion
: public ConvertTritonGPUOpToLLVMPattern<triton::StoreOp>,
public LoadStoreConversionBase {
using ConvertTritonGPUOpToLLVMPattern<
triton::StoreOp>::ConvertTritonGPUOpToLLVMPattern;
StoreOpConversion(LLVMTypeConverter &converter,
AxisInfoAnalysis &axisAnalysisPass, PatternBenefit benefit)
: ConvertTritonGPUOpToLLVMPattern<triton::StoreOp>(converter, benefit),
LoadStoreConversionBase(axisAnalysisPass) {}
LogicalResult
matchAndRewrite(triton::StoreOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
Value ptr = op.ptr();
Value mask = op.mask();
Value value = op.value();
Value llPtr = adaptor.ptr();
Value llMask = adaptor.mask();
Value llValue = adaptor.value();
auto loc = op->getLoc();
MLIRContext *ctx = rewriter.getContext();
auto valueTy = value.getType();
Type valueElemTy =
typeConverter->convertType(getElementTypeOrSelf(valueTy));
unsigned vec = getVectorSize(ptr);
unsigned numElems = getElemsPerThread(ptr.getType());
auto ptrElems = getLLVMElems(ptr, llPtr, rewriter, loc);
auto valueElems = getLLVMElems(value, llValue, rewriter, loc);
assert(ptrElems.size() == valueElems.size());
// Determine the vectorization size
SmallVector<Value> maskElems;
if (llMask) {
maskElems = getLLVMElems(mask, llMask, rewriter, loc);
assert(valueElems.size() == maskElems.size());
unsigned maskAlign = getMaskAlignment(mask);
vec = std::min(vec, maskAlign);
}
const size_t dtsize =
std::max<int>(1, valueElemTy.getIntOrFloatBitWidth() / 8);
const size_t valueElemNbits = dtsize * 8;
const int numVecs = numElems / vec;
for (size_t vecStart = 0; vecStart < numElems; vecStart += vec) {
// TODO: optimization when ptr is AddPtr with constant offset
size_t in_off = 0;
const size_t maxWordWidth = std::max<size_t>(32, valueElemNbits);
const size_t totalWidth = valueElemNbits * vec;
const size_t width = std::min(totalWidth, maxWordWidth);
const size_t nWords = std::max<size_t>(1, totalWidth / width);
const size_t wordNElems = width / valueElemNbits;
assert(wordNElems * nWords * numVecs == numElems);
// TODO(Superjomn) Add cache policy fields to StoreOp.
// TODO(Superjomn) Deal with cache policy here.
Type valArgTy = IntegerType::get(ctx, width);
auto wordTy = vec_ty(valueElemTy, wordNElems);
SmallVector<std::pair<Value, std::string>> asmArgs;
for (size_t wordIdx = 0; wordIdx < nWords; ++wordIdx) {
// llWord is a width-len composition
Value llWord = undef(wordTy);
// Insert each value element to the composition
for (size_t elemIdx = 0; elemIdx < wordNElems; ++elemIdx) {
const size_t elemOffset = vecStart + wordIdx * wordNElems + elemIdx;
assert(elemOffset < valueElems.size());
Value elem = valueElems[elemOffset];
if (elem.getType().isInteger(1))
elem = rewriter.create<LLVM::SExtOp>(loc, type::i8Ty(ctx), elem);
elem = bitcast(elem, valueElemTy);
Type u32Ty = typeConverter->convertType(type::u32Ty(ctx));
llWord = insert_element(wordTy, llWord, elem, i32_val(elemIdx));
}
llWord = bitcast(llWord, valArgTy);
std::string constraint =
(width == 64) ? "l" : ((width == 32) ? "r" : "c");
asmArgs.emplace_back(llWord, constraint);
}
// Prepare the PTX inline asm.
PTXBuilder ptxBuilder;
auto *asmArgList = ptxBuilder.newListOperand(asmArgs);
Value maskVal = llMask ? maskElems[vecStart] : int_val(1, 1);
auto *asmAddr =
ptxBuilder.newAddrOperand(ptrElems[vecStart], "l", in_off);
auto &ptxStoreInstr =
ptxBuilder.create<>("st")->global().v(nWords).b(width);
ptxStoreInstr(asmAddr, asmArgList).predicate(maskVal, "b");
Type boolTy = getTypeConverter()->convertType(rewriter.getIntegerType(1));
llvm::SmallVector<Type> argTys({boolTy, ptr.getType()});
argTys.insert(argTys.end(), nWords, valArgTy);
auto asmReturnTy = void_ty(ctx);
ptxBuilder.launch(rewriter, loc, asmReturnTy);
}
rewriter.eraseOp(op);
return success();
}
};
struct AtomicCASOpConversion
: public ConvertTritonGPUOpToLLVMPattern<triton::AtomicCASOp>,
public LoadStoreConversionBase {
using ConvertTritonGPUOpToLLVMPattern<
triton::AtomicCASOp>::ConvertTritonGPUOpToLLVMPattern;
AtomicCASOpConversion(LLVMTypeConverter &converter,
const Allocation *allocation, Value smem,
AxisInfoAnalysis &axisAnalysisPass,
PatternBenefit benefit)
: ConvertTritonGPUOpToLLVMPattern<triton::AtomicCASOp>(
converter, allocation, smem, benefit),
LoadStoreConversionBase(axisAnalysisPass) {}
LogicalResult
matchAndRewrite(triton::AtomicCASOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
auto loc = op.getLoc();
MLIRContext *ctx = rewriter.getContext();
Value ptr = op.ptr();
Value llPtr = adaptor.ptr();
Value llCmp = adaptor.cmp();
Value llVal = adaptor.val();
auto ptrElements = getElementsFromStruct(loc, llPtr, rewriter);
auto cmpElements = getElementsFromStruct(loc, llCmp, rewriter);
auto valElements = getElementsFromStruct(loc, llVal, rewriter);
auto valueTy = op.getResult().getType().dyn_cast<RankedTensorType>();
Type valueElemTy =
valueTy ? getTypeConverter()->convertType(valueTy.getElementType())
: op.getResult().getType();
auto tid = tid_val();
Value pred = icmp_eq(tid, i32_val(0));
PTXBuilder ptxBuilderMemfence;
auto memfence = ptxBuilderMemfence.create<PTXInstr>("membar")->o("gl");
memfence();
auto ASMReturnTy = void_ty(ctx);
ptxBuilderMemfence.launch(rewriter, loc, ASMReturnTy);
Value atomPtr = getSharedMemoryBase(loc, rewriter, op.getOperation());
atomPtr = bitcast(atomPtr, ptr_ty(valueElemTy, 3));
Value casPtr = ptrElements[0];
Value casCmp = cmpElements[0];
Value casVal = valElements[0];
PTXBuilder ptxBuilderAtomicCAS;
auto *dstOpr = ptxBuilderAtomicCAS.newOperand("=r");
auto *ptrOpr = ptxBuilderAtomicCAS.newAddrOperand(casPtr, "l");
auto *cmpOpr = ptxBuilderAtomicCAS.newOperand(casCmp, "r");
auto *valOpr = ptxBuilderAtomicCAS.newOperand(casVal, "r");
auto &atom = *ptxBuilderAtomicCAS.create<PTXInstr>("atom");
atom.global().o("cas").o("b32");
atom(dstOpr, ptrOpr, cmpOpr, valOpr).predicate(pred);
auto old = ptxBuilderAtomicCAS.launch(rewriter, loc, valueElemTy);
barrier();
PTXBuilder ptxBuilderStore;
auto *dstOprStore = ptxBuilderStore.newAddrOperand(atomPtr, "l");
auto *valOprStore = ptxBuilderStore.newOperand(old, "r");
auto &st = *ptxBuilderStore.create<PTXInstr>("st");
st.shared().o("b32");
st(dstOprStore, valOprStore).predicate(pred);
ptxBuilderStore.launch(rewriter, loc, ASMReturnTy);
ptxBuilderMemfence.launch(rewriter, loc, ASMReturnTy);
barrier();
Value ret = load(atomPtr);
barrier();
rewriter.replaceOp(op, {ret});
return success();
}
};
struct AtomicRMWOpConversion
: public ConvertTritonGPUOpToLLVMPattern<triton::AtomicRMWOp>,
public LoadStoreConversionBase {
using ConvertTritonGPUOpToLLVMPattern<
triton::AtomicRMWOp>::ConvertTritonGPUOpToLLVMPattern;
AtomicRMWOpConversion(LLVMTypeConverter &converter,
const Allocation *allocation, Value smem,
AxisInfoAnalysis &axisAnalysisPass,
PatternBenefit benefit)
: ConvertTritonGPUOpToLLVMPattern<triton::AtomicRMWOp>(
converter, allocation, smem, benefit),
LoadStoreConversionBase(axisAnalysisPass) {}
LogicalResult
matchAndRewrite(triton::AtomicRMWOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
auto loc = op.getLoc();
MLIRContext *ctx = rewriter.getContext();
auto atomicRmwAttr = op.atomic_rmw_op();
Value ptr = op.ptr();
Value val = op.val();
Value llPtr = adaptor.ptr();
Value llVal = adaptor.val();
Value llMask = adaptor.mask();
auto valElements = getElementsFromStruct(loc, llVal, rewriter);
auto ptrElements = getElementsFromStruct(loc, llPtr, rewriter);
auto maskElements = getElementsFromStruct(loc, llMask, rewriter);
auto valueTy = op.getResult().getType().dyn_cast<RankedTensorType>();
Type valueElemTy =
valueTy ? getTypeConverter()->convertType(valueTy.getElementType())
: op.getResult().getType();
const size_t valueElemNbits = valueElemTy.getIntOrFloatBitWidth();
auto elemsPerThread = getElemsPerThread(val.getType());
// vec = 1 for scalar
auto vec = getVectorSize(ptr);
Value mask = int_val(1, 1);
auto tid = tid_val();
// tensor
if (valueTy) {
auto valTy = val.getType().cast<RankedTensorType>();
vec = std::min<unsigned>(vec, valTy.getElementType().isF16() ? 2 : 1);
// mask
auto shape = valueTy.getShape();
auto numElements = product(shape);
mask = and_(mask, icmp_slt(mul(tid, i32_val(elemsPerThread)),
i32_val(numElements)));
}
auto vecTy = vec_ty(valueElemTy, vec);
SmallVector<Value> resultVals(elemsPerThread);
for (size_t i = 0; i < elemsPerThread; i += vec) {
Value rmwVal = undef(vecTy);
for (int ii = 0; ii < vec; ++ii) {
Value iiVal = createIndexAttrConstant(
rewriter, loc, getTypeConverter()->getIndexType(), ii);
rmwVal = insert_element(vecTy, rmwVal, valElements[i + ii], iiVal);
}
Value rmwPtr = ptrElements[i];
Value rmwMask = maskElements[i];
rmwMask = and_(rmwMask, mask);
std::string sTy;
PTXBuilder ptxBuilderAtomicRMW;
std::string tyId = valueElemNbits * vec == 64
? "l"
: (valueElemNbits * vec == 32 ? "r" : "h");
auto *dstOpr = ptxBuilderAtomicRMW.newOperand("=" + tyId);
auto *ptrOpr = ptxBuilderAtomicRMW.newAddrOperand(rmwPtr, "l");
auto *valOpr = ptxBuilderAtomicRMW.newOperand(rmwVal, tyId);
auto &atom = ptxBuilderAtomicRMW.create<>("atom")->global().o("gpu");
auto rmwOp = stringifyRMWOp(atomicRmwAttr).str();
auto sBits = std::to_string(valueElemNbits);
switch (atomicRmwAttr) {
case RMWOp::AND:
sTy = "b" + sBits;
break;
case RMWOp::OR:
sTy = "b" + sBits;
break;
case RMWOp::XOR:
sTy = "b" + sBits;
break;
case RMWOp::ADD:
sTy = "s" + sBits;
break;
case RMWOp::FADD:
rmwOp = "add";
rmwOp += (valueElemNbits == 16 ? ".noftz" : "");
sTy = "f" + sBits;
sTy += (vec == 2 && valueElemNbits == 16) ? "x2" : "";
break;
case RMWOp::MAX:
sTy = "s" + sBits;
break;
case RMWOp::MIN:
sTy = "s" + sBits;
break;
case RMWOp::UMAX:
rmwOp = "max";
sTy = "u" + sBits;
break;
case RMWOp::UMIN:
rmwOp = "min";
sTy = "u" + sBits;
break;
case RMWOp::XCHG:
sTy = "b" + sBits;
break;
default:
return failure();
}
atom.o(rmwOp).o(sTy);
if (valueTy) {
atom(dstOpr, ptrOpr, valOpr).predicate(rmwMask);
auto retType = vec == 1 ? valueElemTy : vecTy;
auto ret = ptxBuilderAtomicRMW.launch(rewriter, loc, retType);
for (int ii = 0; ii < vec; ++ii) {
resultVals[i + ii] =
vec == 1 ? ret : extract_element(valueElemTy, ret, idx_val(ii));
}
} else {
PTXBuilder ptxBuilderMemfence;
auto memfenc = ptxBuilderMemfence.create<PTXInstr>("membar")->o("gl");
memfenc();
auto ASMReturnTy = void_ty(ctx);
ptxBuilderMemfence.launch(rewriter, loc, ASMReturnTy);
rmwMask = and_(rmwMask, icmp_eq(tid, i32_val(0)));
atom(dstOpr, ptrOpr, valOpr).predicate(rmwMask);
auto old = ptxBuilderAtomicRMW.launch(rewriter, loc, valueElemTy);
Value atomPtr = getSharedMemoryBase(loc, rewriter, op.getOperation());
atomPtr = bitcast(atomPtr, ptr_ty(valueElemTy, 3));
store(old, atomPtr);
barrier();
Value ret = load(atomPtr);
barrier();
rewriter.replaceOp(op, {ret});
}
}
if (valueTy) {
Type structTy = getTypeConverter()->convertType(valueTy);
Value resultStruct =
getStructFromElements(loc, resultVals, rewriter, structTy);
rewriter.replaceOp(op, {resultStruct});
}
return success();
}
};
struct InsertSliceOpConversion
: public ConvertTritonGPUOpToLLVMPattern<tensor::InsertSliceOp> {
using ConvertTritonGPUOpToLLVMPattern<
tensor::InsertSliceOp>::ConvertTritonGPUOpToLLVMPattern;
LogicalResult
matchAndRewrite(tensor::InsertSliceOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// %dst = insert_slice %src into %dst[%offsets]
Location loc = op->getLoc();
Value dst = op.dest();
Value src = op.source();
Value res = op.result();
assert(allocation->getBufferId(res) == Allocation::InvalidBufferId &&
"Only support in-place insert_slice for now");
auto srcTy = src.getType().dyn_cast<RankedTensorType>();
auto srcLayout = srcTy.getEncoding().dyn_cast<BlockedEncodingAttr>();
auto srcShape = srcTy.getShape();
assert(srcLayout && "Unexpected srcLayout in InsertSliceOpConversion");
auto dstTy = dst.getType().dyn_cast<RankedTensorType>();
auto dstLayout = dstTy.getEncoding().dyn_cast<SharedEncodingAttr>();
auto llDst = adaptor.dest();
assert(dstLayout && "Unexpected dstLayout in InsertSliceOpConversion");
assert(op.hasUnitStride() &&
"Only unit stride supported by InsertSliceOpConversion");
// newBase = base + offset
// Triton support either static and dynamic offsets
auto smemObj = getSharedMemoryObjectFromStruct(loc, llDst, rewriter);
SmallVector<Value, 4> offsets;
SmallVector<Value, 4> srcStrides;
auto mixedOffsets = op.getMixedOffsets();
for (auto i = 0; i < mixedOffsets.size(); ++i) {
if (op.isDynamicOffset(i)) {
offsets.emplace_back(adaptor.offsets()[i]);
} else {
offsets.emplace_back(i32_val(op.getStaticOffset(i)));
}
// Like insert_slice_async, we only support slice from one dimension,
// which has a slice size of 1
if (op.getStaticSize(i) != 1) {
srcStrides.emplace_back(smemObj.strides[i]);
}
}
// Compute the offset based on the original strides of the shared memory
// object
auto offset = dot(rewriter, loc, offsets, smemObj.strides);
auto elemTy = getTypeConverter()->convertType(dstTy.getElementType());
auto elemPtrTy = ptr_ty(elemTy, 3);
auto smemBase = gep(elemPtrTy, smemObj.base, offset);
auto llSrc = adaptor.source();
auto srcIndices = emitIndices(loc, rewriter, srcLayout, srcShape);
storeDistributedToShared(src, llSrc, srcStrides, srcIndices, dst, smemBase,
elemTy, loc, rewriter);
// Barrier is not necessary.
// The membar pass knows that it writes to shared memory and will handle it
// properly.
rewriter.replaceOp(op, llDst);
return success();
}
};
struct InsertSliceAsyncOpConversion
: public ConvertTritonGPUOpToLLVMPattern<triton::gpu::InsertSliceAsyncOp>,
public LoadStoreConversionBase {
using ConvertTritonGPUOpToLLVMPattern<
triton::gpu::InsertSliceAsyncOp>::ConvertTritonGPUOpToLLVMPattern;
InsertSliceAsyncOpConversion(
LLVMTypeConverter &converter, const Allocation *allocation, Value smem,
ConvertTritonGPUOpToLLVMPatternBase::IndexCacheInfo &indexCacheInfo,
AxisInfoAnalysis &axisAnalysisPass, PatternBenefit benefit)
: ConvertTritonGPUOpToLLVMPattern<triton::gpu::InsertSliceAsyncOp>(
converter, allocation, smem, indexCacheInfo, benefit),
LoadStoreConversionBase(axisAnalysisPass) {}
LogicalResult
matchAndRewrite(triton::gpu::InsertSliceAsyncOp op, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
// insert_slice_async %src, %dst, %index, %mask, %other
auto loc = op.getLoc();
Value src = op.src();
Value dst = op.dst();
Value res = op.result();
Value mask = op.mask();
Value other = op.other();
assert(allocation->getBufferId(res) == Allocation::InvalidBufferId &&
"Only support in-place insert_slice_async for now");
auto srcTy = src.getType().cast<RankedTensorType>();
auto resTy = dst.getType().cast<RankedTensorType>();
auto resElemTy = getTypeConverter()->convertType(resTy.getElementType());
auto srcBlockedLayout = srcTy.getEncoding().cast<BlockedEncodingAttr>();
auto resSharedLayout = resTy.getEncoding().cast<SharedEncodingAttr>();
auto srcShape = srcTy.getShape();
assert(srcShape.size() == 2 &&
"insert_slice_async: Unexpected rank of %src");
Value llDst = adaptor.dst();
Value llSrc = adaptor.src();
Value llMask = adaptor.mask();
Value llOther = adaptor.other();
Value llIndex = adaptor.index();
// %src
auto srcElems = getLLVMElems(src, llSrc, rewriter, loc);
// %dst
auto dstTy = dst.getType().cast<RankedTensorType>();
auto dstShape = dstTy.getShape();
auto smemObj = getSharedMemoryObjectFromStruct(loc, llDst, rewriter);
auto axis = op->getAttrOfType<IntegerAttr>("axis").getInt();
SmallVector<Value, 4> offsetVals;
SmallVector<Value, 4> srcStrides;
for (auto i = 0; i < dstShape.size(); ++i) {
if (i == axis) {
offsetVals.emplace_back(llIndex);
} else {
offsetVals.emplace_back(i32_val(0));
srcStrides.emplace_back(smemObj.strides[i]);
}
}
// Compute the offset based on the original dimensions of the shared
// memory object
auto dstOffset = dot(rewriter, loc, offsetVals, smemObj.strides);
auto dstPtrTy = ptr_ty(resElemTy, 3);
Value dstPtrBase = gep(dstPtrTy, smemObj.base, dstOffset);
// %mask
SmallVector<Value> maskElems;
if (llMask) {
maskElems = getLLVMElems(mask, llMask, rewriter, loc);
assert(srcElems.size() == maskElems.size());
}
// %other
SmallVector<Value> otherElems;
if (llOther) {
// FIXME(Keren): always assume other is 0 for now
// It's not necessary for now because the pipeline pass will skip
// generating insert_slice_async if the load op has any "other" tensor.
// assert(false && "insert_slice_async: Other value not supported yet");
otherElems = getLLVMElems(other, llOther, rewriter, loc);
assert(srcElems.size() == otherElems.size());
}
unsigned inVec = getVectorSize(src);
unsigned outVec = resSharedLayout.getVec();
unsigned minVec = std::min(outVec, inVec);
unsigned numElems = getElemsPerThread(srcTy);
unsigned perPhase = resSharedLayout.getPerPhase();
unsigned maxPhase = resSharedLayout.getMaxPhase();
auto sizePerThread = srcBlockedLayout.getSizePerThread();
auto threadsPerCTA = getThreadsPerCTA(srcBlockedLayout);
auto inOrder = srcBlockedLayout.getOrder();
// If perPhase * maxPhase > threadsPerCTA, we will have elements
// that share the same tile indices. The index calculation will
// be cached.
auto numSwizzleRows = std::max<unsigned>(
(perPhase * maxPhase) / threadsPerCTA[inOrder[1]], 1);
// A sharedLayout encoding has a "vec" parameter.
// On the column dimension, if inVec > outVec, it means we have to divide
// single vector read into multiple ones
auto numVecCols = std::max<unsigned>(inVec / outVec, 1);
auto srcIndices = emitIndices(loc, rewriter, srcBlockedLayout, srcShape);
// <<tileVecIdxRow, tileVecIdxCol>, TileOffset>
DenseMap<std::pair<unsigned, unsigned>, Value> tileOffsetMap;
for (unsigned elemIdx = 0; elemIdx < numElems; elemIdx += minVec) {
// minVec = 2, inVec = 4, outVec = 2
// baseOffsetCol = 0 baseOffsetCol = 0
// tileVecIdxCol = 0 tileVecIdxCol = 1
// -/\- -/\-
// [|x x| |x x| x x x x x]
// [|x x| |x x| x x x x x]
// baseOffsetRow [|x x| |x x| x x x x x]
// [|x x| |x x| x x x x x]
auto vecIdx = elemIdx / minVec;
auto vecIdxCol = vecIdx % (sizePerThread[inOrder[0]] / minVec);
auto vecIdxRow = vecIdx / (sizePerThread[inOrder[0]] / minVec);
auto baseOffsetCol =
vecIdxCol / numVecCols * numVecCols * threadsPerCTA[inOrder[0]];
auto baseOffsetRow = vecIdxRow / numSwizzleRows * numSwizzleRows *
threadsPerCTA[inOrder[1]];
auto tileVecIdxCol = vecIdxCol % numVecCols;
auto tileVecIdxRow = vecIdxRow % numSwizzleRows;
if (!tileOffsetMap.count({tileVecIdxRow, tileVecIdxCol})) {
// Swizzling
// Since the swizzling index is related to outVec, and we know minVec
// already, inVec doesn't matter
//
// (Numbers represent row indices)
// Example1:
// outVec = 2, inVec = 2, minVec = 2
// outVec = 2, inVec = 4, minVec = 2
// | [1 2] [3 4] [5 6] ... |
// | [3 4] [1 2] [7 8] ... |
// | [5 6] [7 8] [1 2] ... |
// Example2:
// outVec = 4, inVec = 2, minVec = 2
// | [1 2 3 4] [5 6 7 8] [9 10 11 12] ... |
// | [5 6 7 8] [1 2 3 4] [13 14 15 16] ... |
// | [9 10 11 12] [13 14 15 16] [1 2 3 4] ... |
auto srcIdx = srcIndices[tileVecIdxRow * sizePerThread[inOrder[0]]];
Value phase = urem(udiv(srcIdx[inOrder[1]], i32_val(perPhase)),
i32_val(maxPhase));
// srcShape and smemObj.shape maybe different if smemObj is a
// slice of the original shared memory object.
// So we need to use the original shape to compute the offset
Value rowOffset = mul(srcIdx[inOrder[1]], srcStrides[inOrder[1]]);
Value colOffset =
add(srcIdx[inOrder[0]], i32_val(tileVecIdxCol * minVec));
Value swizzleIdx = udiv(colOffset, i32_val(outVec));
Value swizzleColOffset =
add(mul(xor_(swizzleIdx, phase), i32_val(outVec)),
urem(colOffset, i32_val(outVec)));
Value tileOffset = add(rowOffset, swizzleColOffset);
tileOffsetMap[{tileVecIdxRow, tileVecIdxCol}] =
gep(dstPtrTy, dstPtrBase, tileOffset);
}
// 16 * 8 = 128bits
auto maxBitWidth =
std::max<unsigned>(128, resElemTy.getIntOrFloatBitWidth());
auto vecBitWidth = resElemTy.getIntOrFloatBitWidth() * minVec;
auto bitWidth = std::min<unsigned>(maxBitWidth, vecBitWidth);
auto numWords = vecBitWidth / bitWidth;
auto numWordElems = bitWidth / resElemTy.getIntOrFloatBitWidth();
// Tune CG and CA here.
auto byteWidth = bitWidth / 8;
CacheModifier srcCacheModifier =
byteWidth == 16 ? CacheModifier::CG : CacheModifier::CA;
assert(byteWidth == 16 || byteWidth == 8 || byteWidth == 4);
auto resByteWidth = resElemTy.getIntOrFloatBitWidth() / 8;
Value tileOffset = tileOffsetMap[{tileVecIdxRow, tileVecIdxCol}];
Value baseOffset =
add(mul(i32_val(baseOffsetRow), srcStrides[inOrder[1]]),
i32_val(baseOffsetCol));
Value basePtr = gep(dstPtrTy, tileOffset, baseOffset);
for (size_t wordIdx = 0; wordIdx < numWords; ++wordIdx) {
PTXBuilder ptxBuilder;
auto wordElemIdx = wordIdx * numWordElems;
auto &copyAsyncOp =
*ptxBuilder.create<PTXCpAsyncLoadInstr>(srcCacheModifier);
auto *dstOperand =
ptxBuilder.newAddrOperand(basePtr, "r", wordElemIdx * resByteWidth);
auto *srcOperand =
ptxBuilder.newAddrOperand(srcElems[elemIdx + wordElemIdx], "l");
auto *copySize = ptxBuilder.newConstantOperand(byteWidth);
auto *srcSize = copySize;
if (op.mask()) {
// We don't use predicate in this case, setting src-size to 0
// if there's any mask. cp.async will automatically fill the
// remaining slots with 0 if cp-size > src-size.
// XXX(Keren): Always assume other = 0 for now.
auto selectOp = select(maskElems[elemIdx + wordElemIdx],
i32_val(byteWidth), i32_val(0));
srcSize = ptxBuilder.newOperand(selectOp, "r");
}
copyAsyncOp(dstOperand, srcOperand, copySize, srcSize);
ptxBuilder.launch(rewriter, loc, void_ty(getContext()));
}
}
PTXBuilder ptxBuilder;
ptxBuilder.create<>("cp.async.commit_group")->operator()();
ptxBuilder.launch(rewriter, loc, void_ty(getContext()));
rewriter.replaceOp(op, llDst);
return success();
}
};
void populateLoadStoreOpToLLVMPatterns(
mlir::LLVMTypeConverter &typeConverter, RewritePatternSet &patterns,
int numWarps, AxisInfoAnalysis &axisInfoAnalysis,
const Allocation *allocation, Value smem,
ConvertTritonGPUOpToLLVMPatternBase::IndexCacheInfo &indexCacheInfo,
PatternBenefit benefit) {
patterns.add<LoadOpConversion>(typeConverter, axisInfoAnalysis, benefit);
patterns.add<StoreOpConversion>(typeConverter, axisInfoAnalysis, benefit);
patterns.add<AtomicCASOpConversion>(typeConverter, allocation, smem,
axisInfoAnalysis, benefit);
patterns.add<AtomicRMWOpConversion>(typeConverter, allocation, smem,
axisInfoAnalysis, benefit);
patterns.add<InsertSliceOpConversion>(typeConverter, allocation, smem,
indexCacheInfo, benefit);
patterns.add<InsertSliceAsyncOpConversion>(typeConverter, allocation, smem,
indexCacheInfo, axisInfoAnalysis,
benefit);
}