1 //===-- MachineFunctionPass.h - Pass for MachineFunctions --------*-C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the MachineFunctionPass class. MachineFunctionPass's are
11 // just FunctionPass's, except they operate on machine code as part of a code
12 // generator. Because they operate on machine code, not the LLVM
13 // representation, MachineFunctionPass's are not allowed to modify the LLVM
14 // representation. Due to this limitation, the MachineFunctionPass class takes
15 // care of declaring that no LLVM passes are invalidated.
17 //===----------------------------------------------------------------------===//
19 #ifndef LLVM_CODEGEN_MACHINEFUNCTIONPASS_H
20 #define LLVM_CODEGEN_MACHINEFUNCTIONPASS_H
22 #include "llvm/Pass.h"
23 #include "llvm/CodeGen/MachineFunction.h"
27 /// MachineFunctionPass - This class adapts the FunctionPass interface to
28 /// allow convenient creation of passes that operate on the MachineFunction
29 /// representation. Instead of overriding runOnFunction, subclasses
30 /// override runOnMachineFunction.
31 class MachineFunctionPass : public FunctionPass {
33 bool doInitialization(Module&) override {
34 // Cache the properties info at module-init time so we don't have to
35 // construct them for every function.
36 RequiredProperties = getRequiredProperties();
37 SetProperties = getSetProperties();
38 ClearedProperties = getClearedProperties();
42 explicit MachineFunctionPass(char &ID) : FunctionPass(ID) {}
44 /// runOnMachineFunction - This method must be overloaded to perform the
45 /// desired machine code transformation or analysis.
47 virtual bool runOnMachineFunction(MachineFunction &MF) = 0;
49 /// getAnalysisUsage - Subclasses that override getAnalysisUsage
52 /// For MachineFunctionPasses, calling AU.preservesCFG() indicates that
53 /// the pass does not modify the MachineBasicBlock CFG.
55 void getAnalysisUsage(AnalysisUsage &AU) const override;
57 virtual MachineFunctionProperties getRequiredProperties() const {
58 return MachineFunctionProperties();
60 virtual MachineFunctionProperties getSetProperties() const {
61 return MachineFunctionProperties();
63 virtual MachineFunctionProperties getClearedProperties() const {
64 return MachineFunctionProperties();
68 MachineFunctionProperties RequiredProperties;
69 MachineFunctionProperties SetProperties;
70 MachineFunctionProperties ClearedProperties;
72 /// createPrinterPass - Get a machine function printer pass.
73 Pass *createPrinterPass(raw_ostream &O,
74 const std::string &Banner) const override;
76 bool runOnFunction(Function &F) override;
79 } // End llvm namespace