llvm-6502/include/llvm/Transforms/Scalar.h
Eli Bendersky 167a57ca45 Add an optimization that does CSE in a group of similar GEPs.
This optimization merges the common part of a group of GEPs, so we can compute
each pointer address by adding a simple offset to the common part.

The optimization is currently only enabled for the NVPTX backend, where it has
a large payoff on some benchmarks.

Review: http://reviews.llvm.org/D3462

Patch by Jingyue Wu.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207783 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-01 18:38:36 +00:00

389 lines
13 KiB
C++

//===-- Scalar.h - Scalar Transformations -----------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This header file defines prototypes for accessor functions that expose passes
// in the Scalar transformations library.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TRANSFORMS_SCALAR_H
#define LLVM_TRANSFORMS_SCALAR_H
#include "llvm/ADT/StringRef.h"
namespace llvm {
class FunctionPass;
class Pass;
class GetElementPtrInst;
class PassInfo;
class TerminatorInst;
class TargetLowering;
class TargetMachine;
//===----------------------------------------------------------------------===//
//
// ConstantPropagation - A worklist driven constant propagation pass
//
FunctionPass *createConstantPropagationPass();
//===----------------------------------------------------------------------===//
//
// SCCP - Sparse conditional constant propagation.
//
FunctionPass *createSCCPPass();
//===----------------------------------------------------------------------===//
//
// DeadInstElimination - This pass quickly removes trivially dead instructions
// without modifying the CFG of the function. It is a BasicBlockPass, so it
// runs efficiently when queued next to other BasicBlockPass's.
//
Pass *createDeadInstEliminationPass();
//===----------------------------------------------------------------------===//
//
// DeadCodeElimination - This pass is more powerful than DeadInstElimination,
// because it is worklist driven that can potentially revisit instructions when
// their other instructions become dead, to eliminate chains of dead
// computations.
//
FunctionPass *createDeadCodeEliminationPass();
//===----------------------------------------------------------------------===//
//
// DeadStoreElimination - This pass deletes stores that are post-dominated by
// must-aliased stores and are not loaded used between the stores.
//
FunctionPass *createDeadStoreEliminationPass();
//===----------------------------------------------------------------------===//
//
// AggressiveDCE - This pass uses the SSA based Aggressive DCE algorithm. This
// algorithm assumes instructions are dead until proven otherwise, which makes
// it more successful are removing non-obviously dead instructions.
//
FunctionPass *createAggressiveDCEPass();
//===----------------------------------------------------------------------===//
//
// SROA - Replace aggregates or pieces of aggregates with scalar SSA values.
//
FunctionPass *createSROAPass(bool RequiresDomTree = true);
//===----------------------------------------------------------------------===//
//
// ScalarReplAggregates - Break up alloca's of aggregates into multiple allocas
// if possible.
//
FunctionPass *createScalarReplAggregatesPass(signed Threshold = -1,
bool UseDomTree = true,
signed StructMemberThreshold = -1,
signed ArrayElementThreshold = -1,
signed ScalarLoadThreshold = -1);
//===----------------------------------------------------------------------===//
//
// InductionVariableSimplify - Transform induction variables in a program to all
// use a single canonical induction variable per loop.
//
Pass *createIndVarSimplifyPass();
//===----------------------------------------------------------------------===//
//
// InstructionCombining - Combine instructions to form fewer, simple
// instructions. This pass does not modify the CFG, and has a tendency to make
// instructions dead, so a subsequent DCE pass is useful.
//
// This pass combines things like:
// %Y = add int 1, %X
// %Z = add int 1, %Y
// into:
// %Z = add int 2, %X
//
FunctionPass *createInstructionCombiningPass();
//===----------------------------------------------------------------------===//
//
// LICM - This pass is a loop invariant code motion and memory promotion pass.
//
Pass *createLICMPass();
//===----------------------------------------------------------------------===//
//
// LoopStrengthReduce - This pass is strength reduces GEP instructions that use
// a loop's canonical induction variable as one of their indices.
//
Pass *createLoopStrengthReducePass();
Pass *createGlobalMergePass(const TargetMachine *TM = nullptr);
//===----------------------------------------------------------------------===//
//
// LoopUnswitch - This pass is a simple loop unswitching pass.
//
Pass *createLoopUnswitchPass(bool OptimizeForSize = false);
//===----------------------------------------------------------------------===//
//
// LoopInstSimplify - This pass simplifies instructions in a loop's body.
//
Pass *createLoopInstSimplifyPass();
//===----------------------------------------------------------------------===//
//
// LoopUnroll - This pass is a simple loop unrolling pass.
//
Pass *createLoopUnrollPass(int Threshold = -1, int Count = -1,
int AllowPartial = -1, int Runtime = -1);
// Create an unrolling pass for full unrolling only.
Pass *createSimpleLoopUnrollPass();
//===----------------------------------------------------------------------===//
//
// LoopReroll - This pass is a simple loop rerolling pass.
//
Pass *createLoopRerollPass();
//===----------------------------------------------------------------------===//
//
// LoopRotate - This pass is a simple loop rotating pass.
//
Pass *createLoopRotatePass();
//===----------------------------------------------------------------------===//
//
// LoopIdiom - This pass recognizes and replaces idioms in loops.
//
Pass *createLoopIdiomPass();
//===----------------------------------------------------------------------===//
//
// PromoteMemoryToRegister - This pass is used to promote memory references to
// be register references. A simple example of the transformation performed by
// this pass is:
//
// FROM CODE TO CODE
// %X = alloca i32, i32 1 ret i32 42
// store i32 42, i32 *%X
// %Y = load i32* %X
// ret i32 %Y
//
FunctionPass *createPromoteMemoryToRegisterPass();
//===----------------------------------------------------------------------===//
//
// DemoteRegisterToMemoryPass - This pass is used to demote registers to memory
// references. In basically undoes the PromoteMemoryToRegister pass to make cfg
// hacking easier.
//
FunctionPass *createDemoteRegisterToMemoryPass();
extern char &DemoteRegisterToMemoryID;
//===----------------------------------------------------------------------===//
//
// Reassociate - This pass reassociates commutative expressions in an order that
// is designed to promote better constant propagation, GCSE, LICM, PRE...
//
// For example: 4 + (x + 5) -> x + (4 + 5)
//
FunctionPass *createReassociatePass();
//===----------------------------------------------------------------------===//
//
// JumpThreading - Thread control through mult-pred/multi-succ blocks where some
// preds always go to some succ.
//
FunctionPass *createJumpThreadingPass();
//===----------------------------------------------------------------------===//
//
// CFGSimplification - Merge basic blocks, eliminate unreachable blocks,
// simplify terminator instructions, etc...
//
FunctionPass *createCFGSimplificationPass();
//===----------------------------------------------------------------------===//
//
// FlattenCFG - flatten CFG, reduce number of conditional branches by using
// parallel-and and parallel-or mode, etc...
//
FunctionPass *createFlattenCFGPass();
//===----------------------------------------------------------------------===//
//
// CFG Structurization - Remove irreducible control flow
//
Pass *createStructurizeCFGPass();
//===----------------------------------------------------------------------===//
//
// BreakCriticalEdges - Break all of the critical edges in the CFG by inserting
// a dummy basic block. This pass may be "required" by passes that cannot deal
// with critical edges. For this usage, a pass must call:
//
// AU.addRequiredID(BreakCriticalEdgesID);
//
// This pass obviously invalidates the CFG, but can update forward dominator
// (set, immediate dominators, tree, and frontier) information.
//
FunctionPass *createBreakCriticalEdgesPass();
extern char &BreakCriticalEdgesID;
//===----------------------------------------------------------------------===//
//
// LoopSimplify - Insert Pre-header blocks into the CFG for every function in
// the module. This pass updates dominator information, loop information, and
// does not add critical edges to the CFG.
//
// AU.addRequiredID(LoopSimplifyID);
//
Pass *createLoopSimplifyPass();
extern char &LoopSimplifyID;
//===----------------------------------------------------------------------===//
//
// TailCallElimination - This pass eliminates call instructions to the current
// function which occur immediately before return instructions.
//
FunctionPass *createTailCallEliminationPass();
//===----------------------------------------------------------------------===//
//
// LowerSwitch - This pass converts SwitchInst instructions into a sequence of
// chained binary branch instructions.
//
FunctionPass *createLowerSwitchPass();
extern char &LowerSwitchID;
//===----------------------------------------------------------------------===//
//
// LowerInvoke - This pass removes invoke instructions, converting them to call
// instructions.
//
FunctionPass *createLowerInvokePass();
extern char &LowerInvokePassID;
//===----------------------------------------------------------------------===//
//
// LCSSA - This pass inserts phi nodes at loop boundaries to simplify other loop
// optimizations.
//
Pass *createLCSSAPass();
extern char &LCSSAID;
//===----------------------------------------------------------------------===//
//
// EarlyCSE - This pass performs a simple and fast CSE pass over the dominator
// tree.
//
FunctionPass *createEarlyCSEPass();
//===----------------------------------------------------------------------===//
//
// GVN - This pass performs global value numbering and redundant load
// elimination cotemporaneously.
//
FunctionPass *createGVNPass(bool NoLoads = false);
//===----------------------------------------------------------------------===//
//
// MemCpyOpt - This pass performs optimizations related to eliminating memcpy
// calls and/or combining multiple stores into memset's.
//
FunctionPass *createMemCpyOptPass();
//===----------------------------------------------------------------------===//
//
// LoopDeletion - This pass performs DCE of non-infinite loops that it
// can prove are dead.
//
Pass *createLoopDeletionPass();
//===----------------------------------------------------------------------===//
//
// ConstantHoisting - This pass prepares a function for expensive constants.
//
FunctionPass *createConstantHoistingPass();
//===----------------------------------------------------------------------===//
//
// InstructionNamer - Give any unnamed non-void instructions "tmp" names.
//
FunctionPass *createInstructionNamerPass();
extern char &InstructionNamerID;
//===----------------------------------------------------------------------===//
//
// Sink - Code Sinking
//
FunctionPass *createSinkingPass();
//===----------------------------------------------------------------------===//
//
// LowerAtomic - Lower atomic intrinsics to non-atomic form
//
Pass *createLowerAtomicPass();
//===----------------------------------------------------------------------===//
//
// ValuePropagation - Propagate CFG-derived value information
//
Pass *createCorrelatedValuePropagationPass();
//===----------------------------------------------------------------------===//
//
// InstructionSimplifier - Remove redundant instructions.
//
FunctionPass *createInstructionSimplifierPass();
extern char &InstructionSimplifierID;
//===----------------------------------------------------------------------===//
//
// LowerExpectIntrinsics - Removes llvm.expect intrinsics and creates
// "block_weights" metadata.
FunctionPass *createLowerExpectIntrinsicPass();
//===----------------------------------------------------------------------===//
//
// PartiallyInlineLibCalls - Tries to inline the fast path of library
// calls such as sqrt.
//
FunctionPass *createPartiallyInlineLibCallsPass();
//===----------------------------------------------------------------------===//
//
// SampleProfilePass - Loads sample profile data from disk and generates
// IR metadata to reflect the profile.
FunctionPass *createSampleProfileLoaderPass();
FunctionPass *createSampleProfileLoaderPass(StringRef Name);
//===----------------------------------------------------------------------===//
//
// ScalarizerPass - Converts vector operations into scalar operations
//
FunctionPass *createScalarizerPass();
//===----------------------------------------------------------------------===//
//
// AddDiscriminators - Add DWARF path discriminators to the IR.
FunctionPass *createAddDiscriminatorsPass();
//===----------------------------------------------------------------------===//
//
// SeparateConstOffsetFromGEP - Split GEPs for better CSE
//
FunctionPass *createSeparateConstOffsetFromGEPPass();
} // End llvm namespace
#endif