66 lines
2.2 KiB
C++
66 lines
2.2 KiB
C++
//===-- ParallelSnippetGenerator.h ------------------------------*- 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
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
///
|
|
/// \file
|
|
/// A SnippetGenerator implementation to create parallel instruction snippets.
|
|
///
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_TOOLS_LLVM_EXEGESIS_PARALLELSNIPPETGENERATOR_H
|
|
#define LLVM_TOOLS_LLVM_EXEGESIS_PARALLELSNIPPETGENERATOR_H
|
|
|
|
#include "SnippetGenerator.h"
|
|
|
|
namespace llvm {
|
|
namespace exegesis {
|
|
|
|
class ParallelSnippetGenerator : public SnippetGenerator {
|
|
public:
|
|
using SnippetGenerator::SnippetGenerator;
|
|
~ParallelSnippetGenerator() override;
|
|
|
|
Expected<std::vector<CodeTemplate>>
|
|
generateCodeTemplates(InstructionTemplate Variant,
|
|
const BitVector &ForbiddenRegisters) const override;
|
|
|
|
static constexpr const size_t kMinNumDifferentAddresses = 6;
|
|
|
|
private:
|
|
// Instantiates memory operands within a snippet.
|
|
// To make computations as parallel as possible, we generate independant
|
|
// memory locations for instructions that load and store. If there are less
|
|
// than kMinNumDifferentAddresses in the original snippet, we duplicate
|
|
// instructions until there are this number of instructions.
|
|
// For example, assuming kMinNumDifferentAddresses=5 and
|
|
// getMaxMemoryAccessSize()=64, if the original snippet is:
|
|
// mov eax, [memory]
|
|
// we might generate:
|
|
// mov eax, [rdi]
|
|
// mov eax, [rdi + 64]
|
|
// mov eax, [rdi + 128]
|
|
// mov eax, [rdi + 192]
|
|
// mov eax, [rdi + 256]
|
|
// If the original snippet is:
|
|
// mov eax, [memory]
|
|
// add eax, [memory]
|
|
// we might generate:
|
|
// mov eax, [rdi]
|
|
// add eax, [rdi + 64]
|
|
// mov eax, [rdi + 128]
|
|
// add eax, [rdi + 192]
|
|
// mov eax, [rdi + 256]
|
|
void instantiateMemoryOperands(
|
|
unsigned ScratchSpaceReg,
|
|
std::vector<InstructionTemplate> &SnippetTemplate) const;
|
|
};
|
|
|
|
} // namespace exegesis
|
|
} // namespace llvm
|
|
|
|
#endif // LLVM_TOOLS_LLVM_EXEGESIS_PARALLELSNIPPETGENERATOR_H
|