1 //===-- Passes.h - Target independent code generation passes ----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines interfaces to access the target independent code generation
11 // passes provided by the LLVM backend.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CODEGEN_PASSES_H
16 #define LLVM_CODEGEN_PASSES_H
22 // PHIElimination pass - This pass eliminates machine instruction PHI nodes by
23 // inserting copy instructions. This destroys SSA information, but is the
24 // desired input for some register allocators. This pass is "required" by these
25 // register allocator like this: AU.addRequiredID(PHIEliminationID);
27 extern const PassInfo *PHIEliminationID;
29 /// Creates a register allocator as the user specified on the command
31 FunctionPass *createRegisterAllocator();
33 /// SimpleRegisterAllocation Pass - This pass converts the input machine code
34 /// from SSA form to use explicit registers by spilling every register. Wow,
37 FunctionPass *createSimpleRegisterAllocator();
39 /// LocalRegisterAllocation Pass - This pass register allocates the input code a
40 /// basic block at a time, yielding code better than the simple register
41 /// allocator, but not as good as a global allocator.
43 FunctionPass *createLocalRegisterAllocator();
45 /// PrologEpilogCodeInserter Pass - This pass inserts prolog and epilog code,
46 /// and eliminates abstract frame references.
48 FunctionPass *createPrologEpilogCodeInserter();
51 /// getRegisterAllocator - This creates an instance of the register allocator
53 FunctionPass *getRegisterAllocator(TargetMachine &T);