tools/llvm-exegesis/lib/CodeTemplate.h

   1 //===-- CodeTemplate.h ------------------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 ///
  10 /// \file
  11 /// A set of structures and functions to craft instructions for the
  12 /// SnippetGenerator.
  13 ///
  14 //===----------------------------------------------------------------------===//
  15
  16 #ifndef LLVM_TOOLS_LLVM_EXEGESIS_CODETEMPLATE_H
  17 #define LLVM_TOOLS_LLVM_EXEGESIS_CODETEMPLATE_H
  18
  19 #include "MCInstrDescView.h"
  20
  21 namespace exegesis {
  22
  23 // A template for an Instruction holding values for each of its Variables.
  24 struct InstructionTemplate {
  25   InstructionTemplate(const Instruction &Instr);
  26
  27   InstructionTemplate(const InstructionTemplate &);            // default
  28   InstructionTemplate &operator=(const InstructionTemplate &); // default
  29   InstructionTemplate(InstructionTemplate &&);                 // default
  30   InstructionTemplate &operator=(InstructionTemplate &&);      // default
  31
  32   unsigned getOpcode() const;
  33   llvm::MCOperand &getValueFor(const Variable &Var);
  34   const llvm::MCOperand &getValueFor(const Variable &Var) const;
  35   llvm::MCOperand &getValueFor(const Operand &Op);
  36   const llvm::MCOperand &getValueFor(const Operand &Op) const;
  37   bool hasImmediateVariables() const;
  38
  39   // Builds an llvm::MCInst from this InstructionTemplate setting its operands
  40   // to the corresponding variable values. Precondition: All VariableValues must
  41   // be set.
  42   llvm::MCInst build() const;
  43
  44   Instruction Instr;
  45   llvm::SmallVector<llvm::MCOperand, 4> VariableValues;
  46 };
  47
  48 // A CodeTemplate is a set of InstructionTemplates that may not be fully
  49 // specified (i.e. some variables are not yet set). This allows the
  50 // BenchmarkRunner to instantiate it many times with specific values to study
  51 // their impact on instruction's performance.
  52 struct CodeTemplate {
  53   CodeTemplate() = default;
  54
  55   CodeTemplate(CodeTemplate &&);            // default
  56   CodeTemplate &operator=(CodeTemplate &&); // default
  57   CodeTemplate(const CodeTemplate &) = delete;
  58   CodeTemplate &operator=(const CodeTemplate &) = delete;
  59
  60   // Some information about how this template has been created.
  61   std::string Info;
  62   // The list of the instructions for this template.
  63   std::vector<InstructionTemplate> Instructions;
  64   // If the template uses the provided scratch memory, the register in which
  65   // the pointer to this memory is passed in to the function.
  66   unsigned ScratchSpacePointerInReg = 0;
  67 };
  68
  69 } // namespace exegesis
  70
  71 #endif // LLVM_TOOLS_LLVM_EXEGESIS_CODETEMPLATE_H