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
27 /// createUnreachableBlockEliminationPass - The LLVM code generator does not
28 /// work well with unreachable basic blocks (what live ranges make sense for a
29 /// block that cannot be reached?). As such, a code generator should either
30 /// not instruction select unreachable blocks, or it can run this pass as it's
31 /// last LLVM modifying pass to clean up blocks that are not reachable from
33 FunctionPass *createUnreachableBlockEliminationPass();
35 /// MachineFunctionPrinter pass - This pass prints out the machine function to
36 /// standard error, as a debugging tool.
37 FunctionPass *createMachineFunctionPrinterPass(std::ostream *OS,
38 const std::string &Banner ="");
40 /// PHIElimination pass - This pass eliminates machine instruction PHI nodes
41 /// by inserting copy instructions. This destroys SSA information, but is the
42 /// desired input for some register allocators. This pass is "required" by
43 /// these register allocator like this: AU.addRequiredID(PHIEliminationID);
45 extern const PassInfo *PHIEliminationID;
47 /// SimpleRegisterCoalescing pass. Aggressively coalesces every register
50 extern const PassInfo *SimpleRegisterCoalescingID;
52 /// TwoAddressInstruction pass - This pass reduces two-address instructions to
53 /// use two operands. This destroys SSA information but it is desired by
54 /// register allocators.
55 extern const PassInfo *TwoAddressInstructionPassID;
57 /// Creates a register allocator as the user specified on the command line.
59 FunctionPass *createRegisterAllocator();
61 /// SimpleRegisterAllocation Pass - This pass converts the input machine code
62 /// from SSA form to use explicit registers by spilling every register. Wow,
65 FunctionPass *createSimpleRegisterAllocator();
67 /// LocalRegisterAllocation Pass - This pass register allocates the input code
68 /// a basic block at a time, yielding code better than the simple register
69 /// allocator, but not as good as a global allocator.
71 FunctionPass *createLocalRegisterAllocator();
73 /// LinearScanRegisterAllocation Pass - This pass implements the linear scan
74 /// register allocation algorithm, a global register allocator.
76 FunctionPass *createLinearScanRegisterAllocator();
78 /// PrologEpilogCodeInserter Pass - This pass inserts prolog and epilog code,
79 /// and eliminates abstract frame references.
81 FunctionPass *createPrologEpilogCodeInserter();
83 /// BranchFolding Pass - This pass performs machine code CFG based
84 /// optimizations to delete branches to branches, eliminate branches to
85 /// successor blocks (creating fall throughs), and eliminating branches over
87 FunctionPass *createBranchFoldingPass(bool DefaultEnableTailMerge);
89 /// IfConverter Pass - This pass performs machine code if conversion.
90 FunctionPass *createIfConverterPass();
92 /// DebugLabelFoldingPass - This pass prunes out redundant debug labels. This
93 /// allows a debug emitter to determine if the range of two labels is empty,
94 /// by seeing if the labels map to the same reduced label.
95 FunctionPass *createDebugLabelFoldingPass();
97 /// MachineCodeDeletion Pass - This pass deletes all of the machine code for
98 /// the current function, which should happen after the function has been
99 /// emitted to a .s file or to memory.
100 FunctionPass *createMachineCodeDeleter();
102 /// getRegisterAllocator - This creates an instance of the register allocator
104 FunctionPass *getRegisterAllocator(TargetMachine &T);
106 //createModuloSchedulingPass - Creates the Swing Modulo Scheduling Pass
107 FunctionPass *createModuloSchedulingPass(TargetMachine & targ);
109 //createModuloSchedulingPass - Creates the Swing Modulo Scheduling Pass
110 FunctionPass *createModuloSchedulingSBPass(TargetMachine & targ);
112 } // End llvm namespace