1 //===-- Passes.h - Target independent code generation passes ----*- C++ -*-===//
3 // This file defines interfaces to access the target independent code generation
4 // passes provided by the LLVM backend.
6 //===----------------------------------------------------------------------===//
8 #ifndef LLVM_CODEGEN_PASSES_H
9 #define LLVM_CODEGEN_PASSES_H
15 // PHIElimination pass - This pass eliminates machine instruction PHI nodes by
16 // inserting copy instructions. This destroys SSA information, but is the
17 // desired input for some register allocators. This pass is "required" by these
18 // register allocator like this: AU.addRequiredID(PHIEliminationID);
20 extern const PassInfo *PHIEliminationID;
22 /// Creates a register allocator as the user specified on the command
24 FunctionPass *createRegisterAllocator();
26 /// SimpleRegisterAllocation Pass - This pass converts the input machine code
27 /// from SSA form to use explicit registers by spilling every register. Wow,
30 FunctionPass *createSimpleRegisterAllocator();
32 /// LocalRegisterAllocation Pass - This pass register allocates the input code a
33 /// basic block at a time, yielding code better than the simple register
34 /// allocator, but not as good as a global allocator.
36 FunctionPass *createLocalRegisterAllocator();
38 /// PrologEpilogCodeInserter Pass - This pass inserts prolog and epilog code,
39 /// and eliminates abstract frame references.
41 FunctionPass *createPrologEpilogCodeInserter();
44 /// getRegisterAllocator - This creates an instance of the register allocator
46 FunctionPass *getRegisterAllocator(TargetMachine &T);