22f0c7a451
Upcoming AMD hardware will include functions that accept 8-bit floats.
Specifically, there are MFMA instructions that accept 8-bit floats,
either using the same or mixed formats. This patch adds MLIR wrappers
for these intrinsics and explicitly adds support for 8-bit floats in
the gpu-to-rocdl conversion by way of amdgpu-to-rocdl.
Since LLVM does not have f8 types, when targeting LLVM for compilation
on an AMD GPU, both f8 types used on AMD hardware (f8E5M2FNUZ and
f8E4M3FNUZ) are rewritten to i8.
This patch also relaxes the restriction that the types of both source
operands to a amdgpu.mfma instructions match exactly, as this is not
necessarily required for the bf8 (f8E5M2FNUZ) and fp8 (f8E4M3FNUZ)
instructions. In addition, since the buffer_{load,store} operations
maintain a whitelist of permitted types, we add the relevant f8 types
to that list.
This patch does not add any implementations of arithmetic operations
for f8 types.
Reviewed By: jakeh-gc
Differential Revision: https://reviews.llvm.org/D143956
256 lines
8.7 KiB
C++
256 lines
8.7 KiB
C++
//===- AMDGPUDialect.cpp - MLIR AMDGPU dialect implementation --------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file implements the AMDGPU dialect and its operations.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "mlir/Dialect/AMDGPU/AMDGPUDialect.h"
|
|
|
|
#include "mlir/Dialect/Arith/IR/Arith.h"
|
|
#include "mlir/Dialect/GPU/IR/GPUDialect.h"
|
|
#include "mlir/IR/Builders.h"
|
|
#include "mlir/IR/BuiltinTypes.h"
|
|
#include "mlir/IR/Diagnostics.h"
|
|
#include "mlir/IR/DialectImplementation.h"
|
|
#include "mlir/IR/Matchers.h"
|
|
#include "mlir/IR/OpImplementation.h"
|
|
#include "mlir/IR/PatternMatch.h"
|
|
#include "mlir/IR/TypeUtilities.h"
|
|
#include "llvm/ADT/TypeSwitch.h"
|
|
|
|
#include <limits>
|
|
#include <optional>
|
|
|
|
using namespace mlir;
|
|
using namespace mlir::amdgpu;
|
|
|
|
#include "mlir/Dialect/AMDGPU/AMDGPUDialect.cpp.inc"
|
|
|
|
void AMDGPUDialect::initialize() {
|
|
addOperations<
|
|
#define GET_OP_LIST
|
|
#include "mlir/Dialect/AMDGPU/AMDGPU.cpp.inc"
|
|
>();
|
|
addAttributes<
|
|
#define GET_ATTRDEF_LIST
|
|
#include "mlir/Dialect/AMDGPU/AMDGPUAttributes.cpp.inc"
|
|
>();
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// RawBuffer*Op
|
|
//===----------------------------------------------------------------------===//
|
|
template <typename T>
|
|
static LogicalResult verifyRawBufferOp(T &op) {
|
|
MemRefType bufferType = op.getMemref().getType().template cast<MemRefType>();
|
|
Attribute memorySpace = bufferType.getMemorySpace();
|
|
bool isGlobal = false;
|
|
if (!memorySpace)
|
|
isGlobal = true;
|
|
else if (auto intMemorySpace = memorySpace.dyn_cast<IntegerAttr>())
|
|
isGlobal = intMemorySpace.getInt() == 0 || intMemorySpace.getInt() == 1;
|
|
else if (auto gpuMemorySpace = memorySpace.dyn_cast<gpu::AddressSpaceAttr>())
|
|
isGlobal = gpuMemorySpace.getValue() == gpu::AddressSpace::Global;
|
|
|
|
if (!isGlobal)
|
|
return op.emitOpError(
|
|
"Buffer ops must operate on a memref in global memory");
|
|
if (!bufferType.hasRank())
|
|
return op.emitOpError(
|
|
"Cannot meaningfully buffer_store to an unranked memref");
|
|
if (static_cast<int64_t>(op.getIndices().size()) != bufferType.getRank())
|
|
return op.emitOpError("Expected " + Twine(bufferType.getRank()) +
|
|
" indices to memref");
|
|
return success();
|
|
}
|
|
|
|
LogicalResult RawBufferLoadOp::verify() { return verifyRawBufferOp(*this); }
|
|
|
|
LogicalResult RawBufferStoreOp::verify() { return verifyRawBufferOp(*this); }
|
|
|
|
LogicalResult RawBufferAtomicFaddOp::verify() {
|
|
return verifyRawBufferOp(*this);
|
|
}
|
|
|
|
static std::optional<uint32_t> getConstantUint32(Value v) {
|
|
APInt cst;
|
|
if (!v.getType().isInteger(32))
|
|
return std::nullopt;
|
|
if (matchPattern(v, m_ConstantInt(&cst)))
|
|
return cst.getZExtValue();
|
|
return std::nullopt;
|
|
}
|
|
|
|
template <typename OpType>
|
|
static bool staticallyOutOfBounds(OpType op) {
|
|
if (!op.getBoundsCheck())
|
|
return false;
|
|
MemRefType bufferType = op.getMemref().getType();
|
|
if (!bufferType.hasStaticShape())
|
|
return false;
|
|
int64_t offset;
|
|
SmallVector<int64_t> strides;
|
|
if (failed(getStridesAndOffset(bufferType, strides, offset)))
|
|
return false;
|
|
int64_t result = offset + op.getIndexOffset().value_or(0);
|
|
if (op.getSgprOffset()) {
|
|
std::optional<uint32_t> sgprOffset = getConstantUint32(op.getSgprOffset());
|
|
if (!sgprOffset)
|
|
return false;
|
|
result += *sgprOffset;
|
|
}
|
|
if (strides.size() != op.getIndices().size())
|
|
return false;
|
|
int64_t indexVal = 0;
|
|
for (auto pair : llvm::zip(strides, op.getIndices())) {
|
|
int64_t stride = std::get<0>(pair);
|
|
Value idx = std::get<1>(pair);
|
|
std::optional<uint32_t> idxVal = getConstantUint32(idx);
|
|
if (!idxVal)
|
|
return false;
|
|
indexVal += stride * *idxVal;
|
|
}
|
|
result += indexVal;
|
|
if (result > std::numeric_limits<uint32_t>::max())
|
|
// Overflow means don't drop
|
|
return false;
|
|
return result >= bufferType.getNumElements();
|
|
}
|
|
|
|
namespace {
|
|
struct RemoveStaticallyOobBufferLoads final
|
|
: public OpRewritePattern<RawBufferLoadOp> {
|
|
using OpRewritePattern<RawBufferLoadOp>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(RawBufferLoadOp op,
|
|
PatternRewriter &rw) const override {
|
|
if (!staticallyOutOfBounds(op))
|
|
return failure();
|
|
Type loadType = op.getResult().getType();
|
|
rw.replaceOpWithNewOp<arith::ConstantOp>(op, loadType,
|
|
rw.getZeroAttr(loadType));
|
|
return success();
|
|
}
|
|
};
|
|
|
|
template <typename OpType>
|
|
struct RemoveStaticallyOobBufferWrites final : public OpRewritePattern<OpType> {
|
|
using OpRewritePattern<OpType>::OpRewritePattern;
|
|
|
|
LogicalResult matchAndRewrite(OpType op, PatternRewriter &rw) const override {
|
|
if (!staticallyOutOfBounds(op))
|
|
return failure();
|
|
|
|
rw.eraseOp(op);
|
|
return success();
|
|
}
|
|
};
|
|
} // end namespace
|
|
|
|
void RawBufferLoadOp::getCanonicalizationPatterns(RewritePatternSet &results,
|
|
MLIRContext *context) {
|
|
results.add<RemoveStaticallyOobBufferLoads>(context);
|
|
}
|
|
|
|
void RawBufferStoreOp::getCanonicalizationPatterns(RewritePatternSet &results,
|
|
MLIRContext *context) {
|
|
results.add<RemoveStaticallyOobBufferWrites<RawBufferStoreOp>>(context);
|
|
}
|
|
|
|
void RawBufferAtomicFaddOp::getCanonicalizationPatterns(
|
|
RewritePatternSet &results, MLIRContext *context) {
|
|
results.add<RemoveStaticallyOobBufferWrites<RawBufferAtomicFaddOp>>(context);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// MFMAOp
|
|
//===----------------------------------------------------------------------===//
|
|
LogicalResult MFMAOp::verify() {
|
|
constexpr uint32_t waveSize = 64;
|
|
Builder b(getContext());
|
|
|
|
Type sourceType = getSourceA().getType();
|
|
Type destType = getDestC().getType();
|
|
|
|
Type sourceElem = sourceType, destElem = destType;
|
|
uint32_t sourceLen = 1, destLen = 1;
|
|
if (auto sourceVector = sourceType.dyn_cast<VectorType>()) {
|
|
sourceLen = sourceVector.getNumElements();
|
|
sourceElem = sourceVector.getElementType();
|
|
}
|
|
if (auto destVector = destType.dyn_cast<VectorType>()) {
|
|
destLen = destVector.getNumElements();
|
|
destElem = destVector.getElementType();
|
|
}
|
|
|
|
Type sourceBType = getSourceB().getType();
|
|
if (sourceElem.isFloat8E5M2FNUZ() || sourceElem.isFloat8E4M3FNUZ()) {
|
|
int64_t sourceBLen = 1;
|
|
Type sourceBElem = sourceBType;
|
|
if (auto sourceBVector = sourceBType.dyn_cast<VectorType>()) {
|
|
sourceBLen = sourceBVector.getNumElements();
|
|
sourceBElem = sourceBVector.getElementType();
|
|
}
|
|
if (!sourceBElem.isFloat8E5M2FNUZ() && !sourceBElem.isFloat8E4M3FNUZ())
|
|
return emitOpError("expected both source operands to have f8 elements");
|
|
if (sourceLen != sourceBLen)
|
|
return emitOpError(
|
|
"expected both f8 source vectors to have the same length");
|
|
} else {
|
|
if (sourceType != sourceBType)
|
|
return emitOpError(
|
|
"expected both non-f8 source operand types to match exactly");
|
|
}
|
|
// Normalize the wider integer types the compiler expects to i8
|
|
if (sourceElem.isInteger(32)) {
|
|
sourceLen *= 4;
|
|
sourceElem = b.getI8Type();
|
|
}
|
|
if (sourceElem.isInteger(64)) {
|
|
sourceLen *= 8;
|
|
sourceElem = b.getI8Type();
|
|
}
|
|
|
|
int64_t numSourceElems = (getM() * getK() * getBlocks()) / waveSize;
|
|
if (sourceLen != numSourceElems)
|
|
return emitOpError("expected " + Twine(numSourceElems) +
|
|
" source values for this operation but got " +
|
|
Twine(sourceLen));
|
|
|
|
int64_t numDestElems = (getM() * getN() * getBlocks()) / waveSize;
|
|
if (destLen != numDestElems)
|
|
return emitOpError("expected " + Twine(numDestElems) +
|
|
" result values for this operation but got " +
|
|
Twine(destLen));
|
|
|
|
if (destElem.isF64() && getBlgp() != MFMAPermB::none)
|
|
return emitOpError(
|
|
"double-precision ops do not support permuting lanes of B");
|
|
if (destElem.isF64() && getCbsz() != 0)
|
|
return emitOpError(
|
|
"double-precision ops do not support permuting lanes of A");
|
|
if (getAbid() >= (1u << getCbsz()))
|
|
return emitOpError(
|
|
"block ID for permuting A (abid) must be below 2 ** cbsz");
|
|
|
|
if ((getNegateA() || getNegateB() || getNegateC()) && !destElem.isF64())
|
|
return emitOpError(
|
|
"negation flags only available for double-precision operations");
|
|
|
|
return success();
|
|
}
|
|
|
|
#include "mlir/Dialect/AMDGPU/AMDGPUEnums.cpp.inc"
|
|
|
|
#define GET_ATTRDEF_CLASSES
|
|
#include "mlir/Dialect/AMDGPU/AMDGPUAttributes.cpp.inc"
|
|
|
|
#define GET_OP_CLASSES
|
|
#include "mlir/Dialect/AMDGPU/AMDGPU.cpp.inc"
|