Files
clang-p2996/mlir/lib/Dialect/Quant/IR/QuantOps.cpp
Rafael Ubal 852b648624 [mlir] Improvements to the 'quant' dialect (#100667)
Full revamp of the 'quant' dialect. This is an implementation for the
RFC at
https://discourse.llvm.org/t/rfc-improvements-in-the-quant-dialect/79942
2024-09-26 14:09:28 -04:00

215 lines
7.6 KiB
C++

//===- QuantOps.cpp - Quantization Type and Ops Implementation --*- C++ -*-===//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "QuantDialectBytecode.h"
#include "TypeDetail.h"
#include "mlir/Dialect/Quant/IR/Quant.h"
#include "mlir/Dialect/Quant/IR/QuantTypes.h"
#include "mlir/IR/BuiltinTypes.h"
#include "mlir/IR/PatternMatch.h"
#include "mlir/IR/TypeUtilities.h"
#include "mlir/Dialect/Quant/IR/QuantOpsDialect.cpp.inc"
namespace mlir {
namespace quant {
namespace {
// Verify the integrity of per-axis quantization information, if present.
//
// - quantizedType
// Any quantized type. Any quantized type with no per-axis quantization is
// ignored.
//
// - containerType
// Original input or result type of the operation using the provided quantized
// type. Used to ensure that the quantized type appears within a tensor and
// that the tensor is compatible with per-axis quantization information.
//
LogicalResult verifyPerAxisQuantization(Operation *op,
QuantizedType quantizedType,
Type containerType) {
auto quantizedPerAxisType = dyn_cast<UniformQuantizedPerAxisType>(quantizedType);
if (!quantizedPerAxisType)
return success();
auto tensorType = dyn_cast<TensorType>(containerType);
if (!tensorType)
return op->emitError("scalar types may not use per-axis quantization");
if (!tensorType.hasRank())
return success();
int64_t quantizedDimension = quantizedPerAxisType.getQuantizedDimension();
if (quantizedDimension >= tensorType.getRank())
return op->emitError("quantized dimension must be less than tensor rank");
int64_t quantizedDimensionSize = tensorType.getDimSize(quantizedDimension);
if (quantizedDimensionSize != ShapedType::kDynamic &&
quantizedDimensionSize != (int64_t)quantizedPerAxisType.getScales().size())
return op->emitError(
"quantized dimension size does not match number of scales");
return success();
}
// Common verification logic for 'quant.dcast' and 'quant.qcast' ops.
//
// - quantizedType
// Quantized type used in the input ('quant.dcast') or result ('quant.qcast'),
// whether as a primitive type or in a tensor.
//
// - floatType
// Float type used in the input ('quant.qcast') or result ('quant.dcast'),
// whether as a primitive type or in a tensor.
//
// - containerType
// Type of original input or result.
//
LogicalResult verifyQuantizationOp(Operation *op, QuantizedType quantizedType,
FloatType floatType, Type containerType) {
if (quantizedType.getExpressedType() != floatType)
return op->emitError(
"expressed type in quantized type expected to match float type");
// Veriy integrity of per-axis quantization information, if present.
return verifyPerAxisQuantization(op, quantizedType, containerType);
}
} // namespace
//===----------------------------------------------------------------------===//
// Dialect
//===----------------------------------------------------------------------===//
void QuantDialect::initialize() {
addTypes<AnyQuantizedType, CalibratedQuantizedType, UniformQuantizedType,
UniformQuantizedPerAxisType>();
addOperations<
#define GET_OP_LIST
#include "mlir/Dialect/Quant/IR/QuantOps.cpp.inc"
>();
detail::addBytecodeInterface(this);
}
//===----------------------------------------------------------------------===//
// DequantizeCastOp
//===----------------------------------------------------------------------===//
LogicalResult DequantizeCastOp::verify() {
return verifyQuantizationOp(*this, getQuantizedType(), getFloatType(),
getInput().getType());
}
OpFoldResult DequantizeCastOp::fold(FoldAdaptor adaptor) {
// Matches x -> quant.qcast -> quant.dcast -> y, replacing the quant.dcast op
// with the value of x. Values x and y are guaranteed to be of the same type
// in this pattern.
auto srcQcastOp = getInput().getDefiningOp<QuantizeCastOp>();
if (!srcQcastOp)
return {};
assert(srcQcastOp.getInput().getType() == getType());
return srcQcastOp.getInput();
}
FloatType DequantizeCastOp::getFloatType() {
return cast<FloatType>(getElementTypeOrSelf(getResult().getType()));
}
QuantizedType DequantizeCastOp::getQuantizedType() {
return cast<QuantizedType>(getElementTypeOrSelf(getInput().getType()));
}
//===----------------------------------------------------------------------===//
// QuantizeCastOp
//===----------------------------------------------------------------------===//
LogicalResult QuantizeCastOp::verify() {
return verifyQuantizationOp(*this, getQuantizedType(), getFloatType(),
getInput().getType());
}
OpFoldResult QuantizeCastOp::fold(FoldAdaptor adaptor) {
// Matches x -> quant.dcast -> quant.qcast -> y, replacing the quant.qcast op
// with the value of x if the casts invert each other. Contrary to the folding
// pattern in quant.dcast (i.e., x -> quant.qcast -> quant.dcast -> y), values
// x and y are not guaranteed to be of the same type here, as they may use
// different quantization parameters.
auto srcDcastOp = getInput().getDefiningOp<DequantizeCastOp>();
if (!srcDcastOp || srcDcastOp.getInput().getType() != getType())
return {};
return srcDcastOp.getInput();
}
FloatType QuantizeCastOp::getFloatType() {
return cast<FloatType>(getElementTypeOrSelf(getInput().getType()));
}
QuantizedType QuantizeCastOp::getQuantizedType() {
return cast<QuantizedType>(getElementTypeOrSelf(getResult().getType()));
}
//===----------------------------------------------------------------------===//
// StorageCastOp
//===----------------------------------------------------------------------===//
LogicalResult StorageCastOp::verify() {
auto quantizedType = getQuantizedType();
auto integerType = getIntegerType();
if (quantizedType.getStorageType() != integerType)
return emitError(
"storage type in quantized type expected to match integer type");
// Verify integrity of per-axis quantization information, if available. While
// the quantization type may appear in the input or the result, their tensor
// shapes are guaranteed to be identical at this point.
return verifyPerAxisQuantization(*this, quantizedType, getInput().getType());
}
OpFoldResult StorageCastOp::fold(FoldAdaptor adaptor) {
// Matches x -> quant.scast -> quant.scast -> y, replacing the second
// quant.scast with the value of x if the casts invert each other.
auto srcScastOp = getInput().getDefiningOp<StorageCastOp>();
if (!srcScastOp || srcScastOp.getInput().getType() != getType())
return {};
return srcScastOp.getInput();
}
IntegerType StorageCastOp::getIntegerType() {
auto inputScalarType = getElementTypeOrSelf(getInput().getType());
if (auto integerType = dyn_cast<IntegerType>(inputScalarType))
return integerType;
auto resultScalarType = getElementTypeOrSelf(getResult().getType());
return cast<IntegerType>(resultScalarType);
}
QuantizedType StorageCastOp::getQuantizedType() {
auto inputScalarType = getElementTypeOrSelf(getInput().getType());
if (auto quantizedType = dyn_cast<QuantizedType>(inputScalarType))
return quantizedType;
auto resultScalarType = getElementTypeOrSelf(getResult().getType());
return cast<QuantizedType>(resultScalarType);
}
} // namespace quant
} // namespace mlir
#define GET_OP_CLASSES
#include "mlir/Dialect/Quant/IR/QuantOps.cpp.inc"