Files
llvm/mlir/lib/Dialect/QuantOps/Transforms/ConvertSimQuant.cpp
Stella Laurenzo d4dcf7de9e Move Quantization -> Dialect/QuantOps, FxpMathOps -> Dialect/FxpMathOps.
Adding the additional layer of directory was discussed offline and matches the Target/ tree. The names match the defacto convention we seem to be following where the C++ namespace is ^(.+)Ops/$ matched against the directory name.

    This is in preparation for patching the Quantizer into this tree, which would have been confusing without moving the Quantization dialect to its more proper home. It is left to others to move other dialects if desired.

    Tested:
      ninja check-mlir

--

PiperOrigin-RevId: 248171982
2019-05-20 13:41:55 -07:00

115 lines
3.9 KiB
C++

//===- ConvertSimQuant.cpp - Converts simulated quant ops------------------===//
//
// Copyright 2019 The MLIR Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// =============================================================================
#include "mlir/Dialect/QuantOps/FakeQuantSupport.h"
#include "mlir/Dialect/QuantOps/Passes.h"
#include "mlir/Dialect/QuantOps/QuantOps.h"
#include "mlir/Dialect/QuantOps/UniformSupport.h"
#include "mlir/IR/Attributes.h"
#include "mlir/IR/PatternMatch.h"
#include "mlir/IR/StandardTypes.h"
#include "mlir/Pass/Pass.h"
using namespace mlir;
using namespace mlir::quant;
namespace {
class ConvertSimulatedQuantPass
: public FunctionPass<ConvertSimulatedQuantPass> {
public:
void runOnFunction() override;
};
} // end anonymous namespace
/// Rewrites ConstFakeQuant into a qbarrier/dbarrier pair.
class ConstFakeQuantRewrite : public RewritePattern {
public:
bool *hadFailure;
ConstFakeQuantRewrite(MLIRContext *context, bool *hadFailure)
: RewritePattern(ConstFakeQuant::getOperationName(), 1, context),
hadFailure(hadFailure) {}
PatternMatchResult matchAndRewrite(Operation *op,
PatternRewriter &rewriter) const override {
// TODO: If this pattern comes up more frequently, consider adding core
// support for failable rewrites.
if (failableRewrite(op, rewriter)) {
*hadFailure = true;
return matchFailure();
}
return matchSuccess();
}
bool failableRewrite(Operation *op, PatternRewriter &rewriter) const {
auto fqOp = cast<ConstFakeQuant>(op);
auto converter =
ExpressedToUniformQuantizedConverter::forInputType(fqOp.getType());
if (!converter) {
return (op->emitError("unsupported quantized type conversion"), true);
}
UniformQuantizedType uniformElementType = fakeQuantAttrsToType(
fqOp.getLoc(), fqOp.num_bits().getSExtValue(),
fqOp.min().convertToFloat(), fqOp.max().convertToFloat(),
fqOp.narrow_range(), converter.expressedType);
if (!uniformElementType) {
// Note that the fakeQuantAttrsToType will have emitted the error.
return true;
}
Type quantizedType = converter.convert(uniformElementType);
assert(quantizedType &&
"Converter accepted a type that it did not convert");
// TODO: Map to a qbarrier with an attribute like [Forced] to signal that
// this is a forced/hard-coded constraint.
auto qbarrier = rewriter.create<QuantizeCastOp>(op->getLoc(), quantizedType,
fqOp.inputs());
rewriter.replaceOpWithNewOp<DequantizeCastOp>(op, converter.inputType,
qbarrier.getResult());
return false;
}
};
void ConvertSimulatedQuantPass::runOnFunction() {
bool hadFailure = false;
OwningRewritePatternList patterns;
auto &func = getFunction();
auto *context = &getContext();
patterns.push_back(
llvm::make_unique<ConstFakeQuantRewrite>(context, &hadFailure));
applyPatternsGreedily(func, std::move(patterns));
if (hadFailure)
signalPassFailure();
}
FunctionPassBase *mlir::quant::createConvertSimulatedQuantPass() {
return new ConvertSimulatedQuantPass();
}
static PassRegistration<ConvertSimulatedQuantPass>
pass("quant-convert-simulated-quantization",
"Converts training-time simulated quantization ops to corresponding "
"quantize/dequantize casts.");