148486893f46d2e12e926682a3ecb908716bc66c4Chris Lattner//===- llvm/Analysis/LoopInfo.h - Natural Loop Calculator -------*- C++ -*-===// 29769ab22265b313171d201b5928688524a01bd87Misha Brukman// 36fbcc26f1460eaee4e0eb8b426fc1ff0c7af11beJohn Criswell// The LLVM Compiler Infrastructure 46fbcc26f1460eaee4e0eb8b426fc1ff0c7af11beJohn Criswell// 57ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// This file is distributed under the University of Illinois Open Source 67ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// License. See LICENSE.TXT for details. 79769ab22265b313171d201b5928688524a01bd87Misha Brukman// 86fbcc26f1460eaee4e0eb8b426fc1ff0c7af11beJohn Criswell//===----------------------------------------------------------------------===// 90bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner// 100bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner// This file defines the LoopInfo class that is used to identify natural loops 11b7532e254810aba26da9b65ee2c65788695f8c30Dan Gohman// and determine the loop depth of various nodes of the CFG. A natural loop 12b7532e254810aba26da9b65ee2c65788695f8c30Dan Gohman// has exactly one entry-point, which is called the header. Note that natural 1346758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner// loops may actually be several loops that share the same header node. 14fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner// 15fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner// This analysis calculates the nesting structure of loops in a function. For 16fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner// each natural loop identified, this analysis identifies natural loops 17072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// contained entirely within the loop and the basic blocks the make up the loop. 18fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner// 19072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// It can calculate on the fly various bits of information, for example: 20072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// 21072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// * whether there is a preheader for the loop 22072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// * the number of back edges to the header 23072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// * whether or not a particular block branches out of the loop 24072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// * the successor blocks of the loop 25072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// * the loop depth 26072b163424491c85df6664a4e056aae5e07dc64dChris Lattner// * etc... 270bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner// 280bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner//===----------------------------------------------------------------------===// 290bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 300bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner#ifndef LLVM_ANALYSIS_LOOP_INFO_H 310bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner#define LLVM_ANALYSIS_LOOP_INFO_H 320bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 33facd752d3afaeca7dee46648f2a2ae209a94e5e9Chris Lattner#include "llvm/Pass.h" 3472851059224b90a3ae74ecd62fbd927a0c54a9f0Cameron Zwarich#include "llvm/ADT/DenseMap.h" 355434c1e73b6e56756719d2aebb952ac7bb3829e0Andrew Trick#include "llvm/ADT/DenseSet.h" 3644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson#include "llvm/ADT/DepthFirstIterator.h" 37551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#include "llvm/ADT/GraphTraits.h" 38b7211a2ce13a0365e0e1dd2f27adda2ee3d1288bDevang Patel#include "llvm/ADT/SmallVector.h" 3992583187306cec18d73db362681ea4f8e2b41909Lang Hames#include "llvm/ADT/STLExtras.h" 4044a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson#include "llvm/Analysis/Dominators.h" 41019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson#include "llvm/Support/CFG.h" 42103289e9383ad1eb66caf28c9b166aebce963a35Chris Lattner#include "llvm/Support/raw_ostream.h" 43019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson#include <algorithm> 449fc5cdf77c812aaa80419036de27576d45894d0dChris Lattner#include <map> 45019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson 461d5562f72e3f7d9e17a2bf95afa54a98dac95894Dan Gohmannamespace llvm { 471d5562f72e3f7d9e17a2bf95afa54a98dac95894Dan Gohman 48019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Andersontemplate<typename T> 49305b515c2787f47adecbe120e4b4bef55c5e5525Chandler Carruthinline void RemoveFromVector(std::vector<T*> &V, T *N) { 50019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson typename std::vector<T*>::iterator I = std::find(V.begin(), V.end(), N); 51019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson assert(I != V.end() && "N is not in this list!"); 52019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson V.erase(I); 53019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson} 540bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 5553c279b1949f7fa626ccbc399ebbe2d7dc9599a4Devang Patelclass DominatorTree; 568fc2f2072de83665ae20e06929e28317f449bcdfChris Lattnerclass LoopInfo; 57c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmanclass Loop; 589fc5cdf77c812aaa80419036de27576d45894d0dChris Lattnerclass PHINode; 59c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmantemplate<class N, class M> class LoopInfoBase; 60c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmantemplate<class N, class M> class LoopBase; 610bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 620bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner//===----------------------------------------------------------------------===// 63131bd2ecf721749666111ec2dd1d32a20ae049b2Chris Lattner/// LoopBase class - Instances of this class are used to represent loops that 64131bd2ecf721749666111ec2dd1d32a20ae049b2Chris Lattner/// are detected in the flow graph 652b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner/// 66c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmantemplate<class BlockT, class LoopT> 67019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Andersonclass LoopBase { 68c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopT *ParentLoop; 69131bd2ecf721749666111ec2dd1d32a20ae049b2Chris Lattner // SubLoops - Loops contained entirely within this one. 70c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman std::vector<LoopT *> SubLoops; 71131bd2ecf721749666111ec2dd1d32a20ae049b2Chris Lattner 72131bd2ecf721749666111ec2dd1d32a20ae049b2Chris Lattner // Blocks - The list of blocks in this loop. First entry is the header node. 73131bd2ecf721749666111ec2dd1d32a20ae049b2Chris Lattner std::vector<BlockT*> Blocks; 74019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson 75c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman // DO NOT IMPLEMENT 76c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopBase(const LoopBase<BlockT, LoopT> &); 77c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman // DO NOT IMPLEMENT 78c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman const LoopBase<BlockT, LoopT>&operator=(const LoopBase<BlockT, LoopT> &); 790bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattnerpublic: 8046758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// Loop ctor - This creates an empty loop. 81019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson LoopBase() : ParentLoop(0) {} 82019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson ~LoopBase() { 8334cd4a484e532cc463fd5a4bf59b88d13c5467c1Evan Cheng for (size_t i = 0, e = SubLoops.size(); i != e; ++i) 844e55b7d2c62de7efa0147e0579980de8b1df9123Chris Lattner delete SubLoops[i]; 854e55b7d2c62de7efa0147e0579980de8b1df9123Chris Lattner } 860bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 87ba42d2b937160c970c8c6ea57573113c9265325fDan Gohman /// getLoopDepth - Return the nesting level of this loop. An outer-most 88ba42d2b937160c970c8c6ea57573113c9265325fDan Gohman /// loop has depth 1, for consistency with loop depth values used for basic 89ba42d2b937160c970c8c6ea57573113c9265325fDan Gohman /// blocks, where depth 0 is used for blocks not inside any loops. 90072b163424491c85df6664a4e056aae5e07dc64dChris Lattner unsigned getLoopDepth() const { 91ba42d2b937160c970c8c6ea57573113c9265325fDan Gohman unsigned D = 1; 92c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman for (const LoopT *CurLoop = ParentLoop; CurLoop; 93019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson CurLoop = CurLoop->ParentLoop) 94072b163424491c85df6664a4e056aae5e07dc64dChris Lattner ++D; 95072b163424491c85df6664a4e056aae5e07dc64dChris Lattner return D; 96072b163424491c85df6664a4e056aae5e07dc64dChris Lattner } 97019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson BlockT *getHeader() const { return Blocks.front(); } 98c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopT *getParentLoop() const { return ParentLoop; } 990bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 10037aa33bc11c01a7142bfa2428a5a4d219b07b6c3Andrew Trick /// setParentLoop is a raw interface for bypassing addChildLoop. 10137aa33bc11c01a7142bfa2428a5a4d219b07b6c3Andrew Trick void setParentLoop(LoopT *L) { ParentLoop = L; } 10237aa33bc11c01a7142bfa2428a5a4d219b07b6c3Andrew Trick 10392329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman /// contains - Return true if the specified loop is contained within in 10492329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman /// this loop. 10592329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman /// 10692329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman bool contains(const LoopT *L) const { 10792329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman if (L == this) return true; 10892329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman if (L == 0) return false; 10992329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman return contains(L->getParentLoop()); 11092329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman } 111fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 11292329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman /// contains - Return true if the specified basic block is in this loop. 113fbdf4bf1799bf9ea566fc0fc0507752590a6d559Misha Brukman /// 114019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson bool contains(const BlockT *BB) const { 115f3ab3a937203d690744357844948faaf96fb73f9Dan Gohman return std::find(block_begin(), block_end(), BB) != block_end(); 116019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson } 1170bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 11892329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman /// contains - Return true if the specified instruction is in this loop. 11992329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman /// 12092329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman template<class InstT> 12192329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman bool contains(const InstT *Inst) const { 12292329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman return contains(Inst->getParent()); 12392329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman } 12492329c7fbe572892c17aa2d2542a10e3ea16132fDan Gohman 125329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner /// iterator/begin/end - Return the loops contained entirely within this loop. 1262b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// 127c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman const std::vector<LoopT *> &getSubLoops() const { return SubLoops; } 12837aa33bc11c01a7142bfa2428a5a4d219b07b6c3Andrew Trick std::vector<LoopT *> &getSubLoopsVector() { return SubLoops; } 129c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman typedef typename std::vector<LoopT *>::const_iterator iterator; 130c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick typedef typename std::vector<LoopT *>::const_reverse_iterator 131c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick reverse_iterator; 132329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner iterator begin() const { return SubLoops.begin(); } 133329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner iterator end() const { return SubLoops.end(); } 134c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick reverse_iterator rbegin() const { return SubLoops.rbegin(); } 135c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick reverse_iterator rend() const { return SubLoops.rend(); } 13621c276d2fa99914d5ed958ac0aec7d78e3dd87cfDan Gohman bool empty() const { return SubLoops.empty(); } 137fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner 138fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner /// getBlocks - Get a list of the basic blocks which make up this loop. 139fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner /// 140019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson const std::vector<BlockT*> &getBlocks() const { return Blocks; } 14137aa33bc11c01a7142bfa2428a5a4d219b07b6c3Andrew Trick std::vector<BlockT*> &getBlocksVector() { return Blocks; } 142019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson typedef typename std::vector<BlockT*>::const_iterator block_iterator; 1434e77cc46ac688e7bee98747049f90e19e2902227Chris Lattner block_iterator block_begin() const { return Blocks.begin(); } 1444e77cc46ac688e7bee98747049f90e19e2902227Chris Lattner block_iterator block_end() const { return Blocks.end(); } 145fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner 146306afdf443a0e2d5d89c1a3ece00cfe18be1c4c4Andrew Trick /// getNumBlocks - Get the number of blocks in this loop in constant time. 147b1eede12818d91a32adac928c6fffcf6d2800dc0Andrew Trick unsigned getNumBlocks() const { 148306afdf443a0e2d5d89c1a3ece00cfe18be1c4c4Andrew Trick return Blocks.size(); 149b1eede12818d91a32adac928c6fffcf6d2800dc0Andrew Trick } 150b1eede12818d91a32adac928c6fffcf6d2800dc0Andrew Trick 151d146e986c818165cca866ee05751451706ccf36aDan Gohman /// isLoopExiting - True if terminator in the block can branch to another 152d146e986c818165cca866ee05751451706ccf36aDan Gohman /// block that is outside of the current loop. 153fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner /// 15432663b719b4996b3a735f22bba80d771d50f96e7Dan Gohman bool isLoopExiting(const BlockT *BB) const { 155d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson typedef GraphTraits<BlockT*> BlockTraits; 156d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson for (typename BlockTraits::ChildIteratorType SI = 157d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson BlockTraits::child_begin(const_cast<BlockT*>(BB)), 158d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson SE = BlockTraits::child_end(const_cast<BlockT*>(BB)); SI != SE; ++SI) { 159019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson if (!contains(*SI)) 160019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson return true; 161019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson } 162019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson return false; 163019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson } 1646b290a54409f6bb6a0cc1c0446cd2b170a4b7addMisha Brukman 165fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner /// getNumBackEdges - Calculate the number of back edges to the loop header 166fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner /// 167019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson unsigned getNumBackEdges() const { 168019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson unsigned NumBackEdges = 0; 169019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson BlockT *H = getHeader(); 170019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson 171d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson typedef GraphTraits<Inverse<BlockT*> > InvBlockTraits; 172d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson for (typename InvBlockTraits::ChildIteratorType I = 173d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson InvBlockTraits::child_begin(const_cast<BlockT*>(H)), 174d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson E = InvBlockTraits::child_end(const_cast<BlockT*>(H)); I != E; ++I) 175019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson if (contains(*I)) 176019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson ++NumBackEdges; 177019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson 178019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson return NumBackEdges; 179019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson } 1809474dd68e8a050193ca4003940ac399e2b17cb6aChris Lattner 181e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner //===--------------------------------------------------------------------===// 182e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner // APIs for simple analysis of the loop. 183e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner // 184e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner // Note that all of these methods can fail on general loops (ie, there may not 185e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner // be a preheader, etc). For best success, the loop simplification and 186e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner // induction variable canonicalization pass should be used to normalize loops 187e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner // for easy analysis. These methods assume canonical loops. 188e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner 1897466ebf045fa5097ee0d7d2728eed7fd5945c8bcChris Lattner /// getExitingBlocks - Return all blocks inside the loop that have successors 1907466ebf045fa5097ee0d7d2728eed7fd5945c8bcChris Lattner /// outside of the loop. These are the blocks _inside of the current loop_ 1917466ebf045fa5097ee0d7d2728eed7fd5945c8bcChris Lattner /// which branch out. The returned list is always unique. 1927466ebf045fa5097ee0d7d2728eed7fd5945c8bcChris Lattner /// 193cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick void getExitingBlocks(SmallVectorImpl<BlockT *> &ExitingBlocks) const; 1947466ebf045fa5097ee0d7d2728eed7fd5945c8bcChris Lattner 195c83324682f3409c15dad992cd62928426c9ad83dDan Gohman /// getExitingBlock - If getExitingBlocks would return exactly one block, 196c83324682f3409c15dad992cd62928426c9ad83dDan Gohman /// return that block. Otherwise return null. 197cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick BlockT *getExitingBlock() const; 198c83324682f3409c15dad992cd62928426c9ad83dDan Gohman 199f1ab4b4eac5603d19c20f4a508f93a118a52bdd5Chris Lattner /// getExitBlocks - Return all of the successor blocks of this loop. These 200f1ab4b4eac5603d19c20f4a508f93a118a52bdd5Chris Lattner /// are the blocks _outside of the current loop_ which are branched to. 201f1ab4b4eac5603d19c20f4a508f93a118a52bdd5Chris Lattner /// 202cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick void getExitBlocks(SmallVectorImpl<BlockT*> &ExitBlocks) const; 203f1ab4b4eac5603d19c20f4a508f93a118a52bdd5Chris Lattner 2041827e8263c9cb5dc29eea4999d8729f7376af4e1Dan Gohman /// getExitBlock - If getExitBlocks would return exactly one block, 2051827e8263c9cb5dc29eea4999d8729f7376af4e1Dan Gohman /// return that block. Otherwise return null. 206cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick BlockT *getExitBlock() const; 2071827e8263c9cb5dc29eea4999d8729f7376af4e1Dan Gohman 20860f422f894ae9aff2f508f34733be36f5a0ed20aLang Hames /// Edge type. 209cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick typedef std::pair<const BlockT*, const BlockT*> Edge; 21060f422f894ae9aff2f508f34733be36f5a0ed20aLang Hames 21155e354ac0e294bde258420f80a2cc11ea19db482Daniel Dunbar /// getExitEdges - Return all pairs of (_inside_block_,_outside_block_). 212cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick void getExitEdges(SmallVectorImpl<Edge> &ExitEdges) const; 21355e354ac0e294bde258420f80a2cc11ea19db482Daniel Dunbar 2142b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// getLoopPreheader - If there is a preheader for this loop, return it. A 2152b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// loop has a preheader if there is only one edge to the header of the loop 2162b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// from outside of the loop. If this is the case, the block branching to the 217e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner /// header of the loop is the preheader node. 2182b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// 219e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner /// This method returns null if there is no preheader for the loop. 2202b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// 221cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick BlockT *getLoopPreheader() const; 2225cf27f81f49b4516b1e9d269f070c88fa3228f9eDan Gohman 2235cf27f81f49b4516b1e9d269f070c88fa3228f9eDan Gohman /// getLoopPredecessor - If the given loop's header has exactly one unique 2245cf27f81f49b4516b1e9d269f070c88fa3228f9eDan Gohman /// predecessor outside the loop, return it. Otherwise return null. 2255cf27f81f49b4516b1e9d269f070c88fa3228f9eDan Gohman /// This is less strict that the loop "preheader" concept, which requires 2265cf27f81f49b4516b1e9d269f070c88fa3228f9eDan Gohman /// the predecessor to have exactly one successor. 2275cf27f81f49b4516b1e9d269f070c88fa3228f9eDan Gohman /// 228cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick BlockT *getLoopPredecessor() const; 2292b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner 230b317143ba851ce2853fb262fb2185ef5f1be030dDan Gohman /// getLoopLatch - If there is a single latch block for this loop, return it. 231b317143ba851ce2853fb262fb2185ef5f1be030dDan Gohman /// A latch block is a block that contains a branch back to the header. 232cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick BlockT *getLoopLatch() const; 233e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner 234e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner //===--------------------------------------------------------------------===// 235e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner // APIs for updating loop information after changing the CFG 236e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner // 237e725cb0d5a8e017b66768eaf186718b36ffea193Chris Lattner 238fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner /// addBasicBlockToLoop - This method is used by other analyses to update loop 239fe3ae1ed660925f06159ec89460d92148e049ffdChris Lattner /// information. NewBB is set to be a new member of the current loop. 2402b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// Because of this, it is added as a member of all parent loops, and is added 2412b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// to the specified LoopInfo object as being in the current basic block. It 2422b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// is not valid to replace the loop header with this method. 2432b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// 244c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman void addBasicBlockToLoop(BlockT *NewBB, LoopInfoBase<BlockT, LoopT> &LI); 2452b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner 24646758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// replaceChildLoopWith - This is used when splitting loops up. It replaces 24746758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// the OldChild entry in our children list with NewChild, and updates the 24846758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// parent pointer of OldChild to be null and the NewChild to be this loop. 24946758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// This updates the loop depth of the new child. 250cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick void replaceChildLoopWith(LoopT *OldChild, LoopT *NewChild); 25146758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner 25246758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// addChildLoop - Add the specified loop to be a child of this loop. This 25346758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// updates the loop depth of the new child. 25446758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// 255c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman void addChildLoop(LoopT *NewChild) { 256019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson assert(NewChild->ParentLoop == 0 && "NewChild already has a parent!"); 257c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman NewChild->ParentLoop = static_cast<LoopT *>(this); 258019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson SubLoops.push_back(NewChild); 259019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson } 26046758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner 26146758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// removeChildLoop - This removes the specified child from being a subloop of 26246758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// this loop. The loop is not deleted, as it will presumably be inserted 26346758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// into another loop. 264c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopT *removeChildLoop(iterator I) { 265019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson assert(I != SubLoops.end() && "Cannot remove end iterator!"); 266c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopT *Child = *I; 267019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson assert(Child->ParentLoop == this && "Child is not a child of this loop!"); 268019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson SubLoops.erase(SubLoops.begin()+(I-begin())); 269019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson Child->ParentLoop = 0; 270019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson return Child; 271019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson } 27246758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner 27346758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// addBlockEntry - This adds a basic block directly to the basic block list. 27446758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// This should only be used by transformations that create new loops. Other 27546758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// transformations should use addBasicBlockToLoop. 276019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson void addBlockEntry(BlockT *BB) { 27746758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner Blocks.push_back(BB); 27846758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner } 27946758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner 28051a4ad475b095aed49caff176b98c0754e421af4Chris Lattner /// moveToHeader - This method is used to move BB (which must be part of this 28151a4ad475b095aed49caff176b98c0754e421af4Chris Lattner /// loop) to be the loop header of the loop (the block that dominates all 28251a4ad475b095aed49caff176b98c0754e421af4Chris Lattner /// others). 283019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson void moveToHeader(BlockT *BB) { 28451a4ad475b095aed49caff176b98c0754e421af4Chris Lattner if (Blocks[0] == BB) return; 28551a4ad475b095aed49caff176b98c0754e421af4Chris Lattner for (unsigned i = 0; ; ++i) { 28651a4ad475b095aed49caff176b98c0754e421af4Chris Lattner assert(i != Blocks.size() && "Loop does not contain BB!"); 28751a4ad475b095aed49caff176b98c0754e421af4Chris Lattner if (Blocks[i] == BB) { 28851a4ad475b095aed49caff176b98c0754e421af4Chris Lattner Blocks[i] = Blocks[0]; 28951a4ad475b095aed49caff176b98c0754e421af4Chris Lattner Blocks[0] = BB; 29051a4ad475b095aed49caff176b98c0754e421af4Chris Lattner return; 29151a4ad475b095aed49caff176b98c0754e421af4Chris Lattner } 29251a4ad475b095aed49caff176b98c0754e421af4Chris Lattner } 29351a4ad475b095aed49caff176b98c0754e421af4Chris Lattner } 29451a4ad475b095aed49caff176b98c0754e421af4Chris Lattner 29546758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// removeBlockFromLoop - This removes the specified basic block from the 296f1ab4b4eac5603d19c20f4a508f93a118a52bdd5Chris Lattner /// current loop, updating the Blocks as appropriate. This does not update 297f1ab4b4eac5603d19c20f4a508f93a118a52bdd5Chris Lattner /// the mapping in the LoopInfo class. 298019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson void removeBlockFromLoop(BlockT *BB) { 299019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson RemoveFromVector(Blocks, BB); 300019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson } 30146758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner 30258e0ef1e90c3f6dbae213612b44e56f7d6d65ea7Devang Patel /// verifyLoop - Verify loop structure 303cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick void verifyLoop() const; 304019b92a70c11319f5ab96c9f5e66e4e111a972f8Owen Anderson 3055c89b5240c90eb8171f999e5f06f815502d0321cDan Gohman /// verifyLoop - Verify loop structure of this loop and all nested loops. 306cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick void verifyLoopNest(DenseSet<const LoopT*> *Loops) const; 30758e0ef1e90c3f6dbae213612b44e56f7d6d65ea7Devang Patel 308cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick void print(raw_ostream &OS, unsigned Depth = 0) const; 309dda30cd4af1c5f88fc00fd40b673f8e27c61379dDan Gohman 310c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmanprotected: 311c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman friend class LoopInfoBase<BlockT, LoopT>; 3121002c0203450620594a85454c6a095ca94b87cb2Dan Gohman explicit LoopBase(BlockT *BB) : ParentLoop(0) { 313072b163424491c85df6664a4e056aae5e07dc64dChris Lattner Blocks.push_back(BB); 3140bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner } 3150bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner}; 3160bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 3176a0dc079efe7acf7e71cc4c0948fe814f35ba091Jakob Stoklund Olesentemplate<class BlockT, class LoopT> 3186a0dc079efe7acf7e71cc4c0948fe814f35ba091Jakob Stoklund Olesenraw_ostream& operator<<(raw_ostream &OS, const LoopBase<BlockT, LoopT> &Loop) { 3196a0dc079efe7acf7e71cc4c0948fe814f35ba091Jakob Stoklund Olesen Loop.print(OS); 3206a0dc079efe7acf7e71cc4c0948fe814f35ba091Jakob Stoklund Olesen return OS; 3216a0dc079efe7acf7e71cc4c0948fe814f35ba091Jakob Stoklund Olesen} 3226a0dc079efe7acf7e71cc4c0948fe814f35ba091Jakob Stoklund Olesen 32360c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick// Implementation in LoopInfoImpl.h 32460c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick#ifdef __GNUC__ 32560c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick__extension__ extern template class LoopBase<BasicBlock, Loop>; 32660c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick#endif 32760c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick 328c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmanclass Loop : public LoopBase<BasicBlock, Loop> { 329c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmanpublic: 330c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman Loop() {} 33116a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman 33216a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// isLoopInvariant - Return true if the specified value is loop invariant 33316a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// 33416a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman bool isLoopInvariant(Value *V) const; 33516a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman 336adc799112dc180b3cd099038c05101b85d217716Chris Lattner /// hasLoopInvariantOperands - Return true if all the operands of the 337fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick /// specified instruction are loop invariant. 338adc799112dc180b3cd099038c05101b85d217716Chris Lattner bool hasLoopInvariantOperands(Instruction *I) const; 339a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman 340206613b289f60b71a76e9190d36b9ea9e47a701eDan Gohman /// makeLoopInvariant - If the given value is an instruction inside of the 341a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// loop and it can be hoisted, do so to make it trivially loop-invariant. 342a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// Return true if the value after any hoisting is loop invariant. This 343a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// function can be used as a slightly more aggressive replacement for 344a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// isLoopInvariant. 345a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// 346a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// If InsertPt is specified, it is the point to hoist instructions to. 347a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// If null, the terminator of the loop preheader is used. 348a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// 349bdc017edacb713119b24ab269d250a82d62fffebDan Gohman bool makeLoopInvariant(Value *V, bool &Changed, 350bdc017edacb713119b24ab269d250a82d62fffebDan Gohman Instruction *InsertPt = 0) const; 351a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman 352a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// makeLoopInvariant - If the given instruction is inside of the 353a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// loop and it can be hoisted, do so to make it trivially loop-invariant. 354a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// Return true if the instruction after any hoisting is loop invariant. This 355a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// function can be used as a slightly more aggressive replacement for 356a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// isLoopInvariant. 357a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// 358a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// If InsertPt is specified, it is the point to hoist instructions to. 359a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// If null, the terminator of the loop preheader is used. 360a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman /// 361bdc017edacb713119b24ab269d250a82d62fffebDan Gohman bool makeLoopInvariant(Instruction *I, bool &Changed, 362bdc017edacb713119b24ab269d250a82d62fffebDan Gohman Instruction *InsertPt = 0) const; 363a342026504e65e2c8dc5600dab4b45ab4f94026dDan Gohman 36416a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// getCanonicalInductionVariable - Check to see if the loop has a canonical 36516a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// induction variable: an integer recurrence that starts at 0 and increments 36616a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// by one each time through the loop. If so, return the phi node that 36716a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// corresponds to it. 36816a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// 36916a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// The IndVarSimplify pass transforms loops to have a canonical induction 37016a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// variable. 37116a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// 37216a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman PHINode *getCanonicalInductionVariable() const; 37316a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman 37416a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman /// isLCSSAForm - Return true if the Loop is in LCSSA form 375bbf81d88116d23fb0776412b5916f7d0b8b3ca7eDan Gohman bool isLCSSAForm(DominatorTree &DT) const; 37616a2c927e95c29a316d0271c93e0490ce3bc06ceDan Gohman 377937738649386b8188524d0cd61943214a5b93cf6Dan Gohman /// isLoopSimplifyForm - Return true if the Loop is in the form that 378937738649386b8188524d0cd61943214a5b93cf6Dan Gohman /// the LoopSimplify form transforms loops to, which is sometimes called 379937738649386b8188524d0cd61943214a5b93cf6Dan Gohman /// normal form. 380937738649386b8188524d0cd61943214a5b93cf6Dan Gohman bool isLoopSimplifyForm() const; 381937738649386b8188524d0cd61943214a5b93cf6Dan Gohman 382d9fc1ce8096f7138c60edc3a6655583bf209780eAndrew Trick /// isSafeToClone - Return true if the loop body is safe to clone in practice. 383d9fc1ce8096f7138c60edc3a6655583bf209780eAndrew Trick bool isSafeToClone() const; 384d9fc1ce8096f7138c60edc3a6655583bf209780eAndrew Trick 385f17e9511f15a0e007ff47d0789d1a52502e8c1fbDan Gohman /// hasDedicatedExits - Return true if no exit block for the loop 386f17e9511f15a0e007ff47d0789d1a52502e8c1fbDan Gohman /// has a predecessor that is outside the loop. 387f17e9511f15a0e007ff47d0789d1a52502e8c1fbDan Gohman bool hasDedicatedExits() const; 388f17e9511f15a0e007ff47d0789d1a52502e8c1fbDan Gohman 389fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick /// getUniqueExitBlocks - Return all unique successor blocks of this loop. 390f0608d829a7b8929108ac6718bd866adf710e936Dan Gohman /// These are the blocks _outside of the current loop_ which are branched to. 391050959cd08db6c0efb8208271a1d64ce58893e20Dan Gohman /// This assumes that loop exits are in canonical form. 392f0608d829a7b8929108ac6718bd866adf710e936Dan Gohman /// 393f0608d829a7b8929108ac6718bd866adf710e936Dan Gohman void getUniqueExitBlocks(SmallVectorImpl<BasicBlock *> &ExitBlocks) const; 394f0608d829a7b8929108ac6718bd866adf710e936Dan Gohman 395f0608d829a7b8929108ac6718bd866adf710e936Dan Gohman /// getUniqueExitBlock - If getUniqueExitBlocks would return exactly one 396f0608d829a7b8929108ac6718bd866adf710e936Dan Gohman /// block, return that block. Otherwise return null. 397f0608d829a7b8929108ac6718bd866adf710e936Dan Gohman BasicBlock *getUniqueExitBlock() const; 398f0608d829a7b8929108ac6718bd866adf710e936Dan Gohman 399dda30cd4af1c5f88fc00fd40b673f8e27c61379dDan Gohman void dump() const; 400fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 401c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmanprivate: 402c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman friend class LoopInfoBase<BasicBlock, Loop>; 403c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman explicit Loop(BasicBlock *BB) : LoopBase<BasicBlock, Loop>(BB) {} 404c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman}; 4050bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 4060bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner//===----------------------------------------------------------------------===// 4072b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner/// LoopInfo - This class builds and contains all of the top level loop 4082b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner/// structures in the specified function. 4092b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner/// 41044a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 411c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohmantemplate<class BlockT, class LoopT> 41244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Andersonclass LoopInfoBase { 4130bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner // BBMap - Mapping of basic blocks to the inner most loop they occur in 41472851059224b90a3ae74ecd62fbd927a0c54a9f0Cameron Zwarich DenseMap<BlockT *, LoopT *> BBMap; 415c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman std::vector<LoopT *> TopLevelLoops; 416c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman friend class LoopBase<BlockT, LoopT>; 4175434c1e73b6e56756719d2aebb952ac7bb3829e0Andrew Trick friend class LoopInfo; 4189d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman 4199d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman void operator=(const LoopInfoBase &); // do not implement 4209d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman LoopInfoBase(const LoopInfo &); // do not implement 4210bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattnerpublic: 42244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson LoopInfoBase() { } 42344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson ~LoopInfoBase() { releaseMemory(); } 424fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 42544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson void releaseMemory() { 426c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman for (typename std::vector<LoopT *>::iterator I = 42744a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson TopLevelLoops.begin(), E = TopLevelLoops.end(); I != E; ++I) 42844a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson delete *I; // Delete all of the loops... 4290bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 430131bd2ecf721749666111ec2dd1d32a20ae049b2Chris Lattner BBMap.clear(); // Reset internal state of analysis 43144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson TopLevelLoops.clear(); 43244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 433fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 434329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner /// iterator/begin/end - The interface to the top-level loops in the current 435329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner /// function. 436329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner /// 437c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman typedef typename std::vector<LoopT *>::const_iterator iterator; 438c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick typedef typename std::vector<LoopT *>::const_reverse_iterator 439c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick reverse_iterator; 440329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner iterator begin() const { return TopLevelLoops.begin(); } 441329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner iterator end() const { return TopLevelLoops.end(); } 442c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick reverse_iterator rbegin() const { return TopLevelLoops.rbegin(); } 443c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick reverse_iterator rend() const { return TopLevelLoops.rend(); } 444a8c763b3071ae1a58ee8baeb282331245527e004Dan Gohman bool empty() const { return TopLevelLoops.empty(); } 445fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 4462b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// getLoopFor - Return the inner most loop that BB lives in. If a basic 4472b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// block is in no loop (for example the entry node), null is returned. 4482b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// 449c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopT *getLoopFor(const BlockT *BB) const { 450da69f3b357097e75fbf9a5a2bbe1e7273d4b4271Benjamin Kramer return BBMap.lookup(const_cast<BlockT*>(BB)); 4510bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner } 452fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 4532b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// operator[] - same as getLoopFor... 4542b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// 455c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman const LoopT *operator[](const BlockT *BB) const { 4560bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner return getLoopFor(BB); 4570bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner } 458fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 459ba42d2b937160c970c8c6ea57573113c9265325fDan Gohman /// getLoopDepth - Return the loop nesting level of the specified block. A 460ba42d2b937160c970c8c6ea57573113c9265325fDan Gohman /// depth of 0 means the block is not inside any loop. 4612b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// 46244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson unsigned getLoopDepth(const BlockT *BB) const { 463c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman const LoopT *L = getLoopFor(BB); 4640bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner return L ? L->getLoopDepth() : 0; 4650bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner } 4660bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 4670bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner // isLoopHeader - True if the block is a loop header node 46844a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson bool isLoopHeader(BlockT *BB) const { 469c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman const LoopT *L = getLoopFor(BB); 47050f5490842d501e269a4c6085d0d132cae0d31f8Chris Lattner return L && L->getHeader() == BB; 4710bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner } 472fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 47344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// removeLoop - This removes the specified top-level loop from this loop info 47444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// object. The loop is not deleted, as it will presumably be inserted into 47544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// another loop. 476c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopT *removeLoop(iterator I) { 47744a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson assert(I != end() && "Cannot remove end iterator!"); 478c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopT *L = *I; 47944a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson assert(L->getParentLoop() == 0 && "Not a top-level loop!"); 48044a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson TopLevelLoops.erase(TopLevelLoops.begin() + (I-begin())); 48144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson return L; 48244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 483fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 48444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// changeLoopFor - Change the top-level loop that contains BB to the 48544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// specified loop. This should be used by transformations that restructure 48644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// the loop hierarchy tree. 487c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman void changeLoopFor(BlockT *BB, LoopT *L) { 488fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick if (!L) { 489da69f3b357097e75fbf9a5a2bbe1e7273d4b4271Benjamin Kramer BBMap.erase(BB); 490fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick return; 491fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick } 492fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick BBMap[BB] = L; 49344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 494fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 49544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// changeTopLevelLoop - Replace the specified loop in the top-level loops 49644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// list with the indicated loop. 497c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman void changeTopLevelLoop(LoopT *OldLoop, 498c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopT *NewLoop) { 499c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman typename std::vector<LoopT *>::iterator I = 50044a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson std::find(TopLevelLoops.begin(), TopLevelLoops.end(), OldLoop); 50144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson assert(I != TopLevelLoops.end() && "Old loop not at top level!"); 50244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson *I = NewLoop; 50344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson assert(NewLoop->ParentLoop == 0 && OldLoop->ParentLoop == 0 && 50444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson "Loops already embedded into a subloop!"); 50544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 506fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 50744a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// addTopLevelLoop - This adds the specified loop to the collection of 50844a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// top-level loops. 509c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman void addTopLevelLoop(LoopT *New) { 51044a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson assert(New->getParentLoop() == 0 && "Loop already in subloop!"); 51144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson TopLevelLoops.push_back(New); 51244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 513fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 51444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// removeBlock - This method completely removes BB from all data structures, 51544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// including all of the Loop objects it is nested in and our mapping from 51644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// BasicBlocks to loops. 51744a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson void removeBlock(BlockT *BB) { 51872851059224b90a3ae74ecd62fbd927a0c54a9f0Cameron Zwarich typename DenseMap<BlockT *, LoopT *>::iterator I = BBMap.find(BB); 51944a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson if (I != BBMap.end()) { 520c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman for (LoopT *L = I->second; L; L = L->getParentLoop()) 52144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson L->removeBlockFromLoop(BB); 52244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 52344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson BBMap.erase(I); 52444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 52544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 526fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 52744a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson // Internals 528fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 529c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman static bool isNotAlreadyContainedIn(const LoopT *SubLoop, 530c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman const LoopT *ParentLoop) { 53144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson if (SubLoop == 0) return true; 53244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson if (SubLoop == ParentLoop) return false; 53344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson return isNotAlreadyContainedIn(SubLoop->getParentLoop(), ParentLoop); 53444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 535fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 53637aa33bc11c01a7142bfa2428a5a4d219b07b6c3Andrew Trick /// Create the loop forest using a stable algorithm. 53737aa33bc11c01a7142bfa2428a5a4d219b07b6c3Andrew Trick void Analyze(DominatorTreeBase<BlockT> &DomTree); 53837aa33bc11c01a7142bfa2428a5a4d219b07b6c3Andrew Trick 53944a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson // Debugging 540fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 541cbf24b4e58c2f621f480883c5bb1f2f2b2b8d497Andrew Trick void print(raw_ostream &OS) const; 54244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson}; 54344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 54460c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick// Implementation in LoopInfoImpl.h 54560c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick#ifdef __GNUC__ 54660c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick__extension__ extern template class LoopInfoBase<BasicBlock, Loop>; 54760c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick#endif 54860c7d5bc2cbeff9eff16716295ffd6a5374dc6bcAndrew Trick 54944a95e06cc0bb3a2d617fe94235aee92b1951910Owen Andersonclass LoopInfo : public FunctionPass { 550c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopInfoBase<BasicBlock, Loop> LI; 551c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman friend class LoopBase<BasicBlock, Loop>; 5529d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman 5539d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman void operator=(const LoopInfo &); // do not implement 5549d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman LoopInfo(const LoopInfo &); // do not implement 55544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Andersonpublic: 55644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson static char ID; // Pass identification, replacement for typeid 55744a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 558081c34b725980f995be9080eaec24cd3dfaaf065Owen Anderson LoopInfo() : FunctionPass(ID) { 559081c34b725980f995be9080eaec24cd3dfaaf065Owen Anderson initializeLoopInfoPass(*PassRegistry::getPassRegistry()); 560081c34b725980f995be9080eaec24cd3dfaaf065Owen Anderson } 56144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 562c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman LoopInfoBase<BasicBlock, Loop>& getBase() { return LI; } 563d735ee85dbab8e4f66f9ec157f19956e0d11ec7aOwen Anderson 56444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// iterator/begin/end - The interface to the top-level loops in the current 56544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// function. 56644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// 567c8d76d5afb023a1c6b439941be3b62789fcc0ed3Dan Gohman typedef LoopInfoBase<BasicBlock, Loop>::iterator iterator; 568c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick typedef LoopInfoBase<BasicBlock, Loop>::reverse_iterator reverse_iterator; 5699d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman inline iterator begin() const { return LI.begin(); } 5709d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman inline iterator end() const { return LI.end(); } 571c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick inline reverse_iterator rbegin() const { return LI.rbegin(); } 572c9b1e25493b393013b28e5d457f2fb2845a4dd9fAndrew Trick inline reverse_iterator rend() const { return LI.rend(); } 5739d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman bool empty() const { return LI.empty(); } 57444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 57544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// getLoopFor - Return the inner most loop that BB lives in. If a basic 57644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// block is in no loop (for example the entry node), null is returned. 57744a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// 57844a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson inline Loop *getLoopFor(const BasicBlock *BB) const { 5799d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman return LI.getLoopFor(BB); 58044a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 58144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 58244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// operator[] - same as getLoopFor... 58344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// 58444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson inline const Loop *operator[](const BasicBlock *BB) const { 5859d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman return LI.getLoopFor(BB); 58644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 58744a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 588ba42d2b937160c970c8c6ea57573113c9265325fDan Gohman /// getLoopDepth - Return the loop nesting level of the specified block. A 589ba42d2b937160c970c8c6ea57573113c9265325fDan Gohman /// depth of 0 means the block is not inside any loop. 59044a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson /// 59144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson inline unsigned getLoopDepth(const BasicBlock *BB) const { 5929d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman return LI.getLoopDepth(BB); 59344a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 59444a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson 59544a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson // isLoopHeader - True if the block is a loop header node 59644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson inline bool isLoopHeader(BasicBlock *BB) const { 5979d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman return LI.isLoopHeader(BB); 59844a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 5990bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 6002b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// runOnFunction - Calculate the natural loop information. 6012b7bb7a986545b5ec877416278dc126a35ab6970Chris Lattner /// 6027e70829632f82de15db187845666aaca6e04b792Chris Lattner virtual bool runOnFunction(Function &F); 603facd752d3afaeca7dee46648f2a2ae209a94e5e9Chris Lattner 6045c89b5240c90eb8171f999e5f06f815502d0321cDan Gohman virtual void verifyAnalysis() const; 6055c89b5240c90eb8171f999e5f06f815502d0321cDan Gohman 6069d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman virtual void releaseMemory() { LI.releaseMemory(); } 6075c7e326585f3a543388ba871c3425f7664cd9143Bill Wendling 60845cfe545ec8177262dabc70580ce05feaa1c3880Chris Lattner virtual void print(raw_ostream &O, const Module* M = 0) const; 609fbfb806e3fe697fd8ee2a59f8fd3e0790ccf0d3cAndrew Trick 610f57b845547302d24ecb6a9e79d7bc386f761a6c9Chris Lattner virtual void getAnalysisUsage(AnalysisUsage &AU) const; 611f57b845547302d24ecb6a9e79d7bc386f761a6c9Chris Lattner 6124e55b7d2c62de7efa0147e0579980de8b1df9123Chris Lattner /// removeLoop - This removes the specified top-level loop from this loop info 6134e55b7d2c62de7efa0147e0579980de8b1df9123Chris Lattner /// object. The loop is not deleted, as it will presumably be inserted into 6144e55b7d2c62de7efa0147e0579980de8b1df9123Chris Lattner /// another loop. 6159d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman inline Loop *removeLoop(iterator I) { return LI.removeLoop(I); } 6164e55b7d2c62de7efa0147e0579980de8b1df9123Chris Lattner 61746758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// changeLoopFor - Change the top-level loop that contains BB to the 61846758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// specified loop. This should be used by transformations that restructure 61946758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// the loop hierarchy tree. 62044a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson inline void changeLoopFor(BasicBlock *BB, Loop *L) { 6219d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman LI.changeLoopFor(BB, L); 62244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 62346758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner 62446758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// changeTopLevelLoop - Replace the specified loop in the top-level loops 62546758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner /// list with the indicated loop. 62644a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson inline void changeTopLevelLoop(Loop *OldLoop, Loop *NewLoop) { 6279d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman LI.changeTopLevelLoop(OldLoop, NewLoop); 62844a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 62946758a894f5d9ca7adc8ec03dd6adeb36b7eadb3Chris Lattner 630072b163424491c85df6664a4e056aae5e07dc64dChris Lattner /// addTopLevelLoop - This adds the specified loop to the collection of 631072b163424491c85df6664a4e056aae5e07dc64dChris Lattner /// top-level loops. 63244a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson inline void addTopLevelLoop(Loop *New) { 6339d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman LI.addTopLevelLoop(New); 634072b163424491c85df6664a4e056aae5e07dc64dChris Lattner } 635072b163424491c85df6664a4e056aae5e07dc64dChris Lattner 6369afb24bf0847b9f2ff0bf3f7f7405dcbe42fa38bChris Lattner /// removeBlock - This method completely removes BB from all data structures, 6379afb24bf0847b9f2ff0bf3f7f7405dcbe42fa38bChris Lattner /// including all of the Loop objects it is nested in and our mapping from 6389afb24bf0847b9f2ff0bf3f7f7405dcbe42fa38bChris Lattner /// BasicBlocks to loops. 63944a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson void removeBlock(BasicBlock *BB) { 6409d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman LI.removeBlock(BB); 64144a95e06cc0bb3a2d617fe94235aee92b1951910Owen Anderson } 642d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands 643fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick /// updateUnloop - Update LoopInfo after removing the last backedge from a 644fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick /// loop--now the "unloop". This updates the loop forest and parent loops for 645fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick /// each block so that Unloop is no longer referenced, but the caller must 646fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick /// actually delete the Unloop object. 647fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick void updateUnloop(Loop *Unloop); 648fb62b8deb3c837bc5f4cf98543b89d08e7db9f84Andrew Trick 649d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands /// replacementPreservesLCSSAForm - Returns true if replacing From with To 650d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands /// everywhere is guaranteed to preserve LCSSA form. 651d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands bool replacementPreservesLCSSAForm(Instruction *From, Value *To) { 652d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands // Preserving LCSSA form is only problematic if the replacing value is an 653d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands // instruction. 654d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands Instruction *I = dyn_cast<Instruction>(To); 655d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands if (!I) return true; 6569bc6a90146417af03144fa2f7dd94f9945b57c06Duncan Sands // If both instructions are defined in the same basic block then replacement 6579bc6a90146417af03144fa2f7dd94f9945b57c06Duncan Sands // cannot break LCSSA form. 6589bc6a90146417af03144fa2f7dd94f9945b57c06Duncan Sands if (I->getParent() == From->getParent()) 6599bc6a90146417af03144fa2f7dd94f9945b57c06Duncan Sands return true; 660d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands // If the instruction is not defined in a loop then it can safely replace 661d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands // anything. 662d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands Loop *ToLoop = getLoopFor(I->getParent()); 663d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands if (!ToLoop) return true; 664d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands // If the replacing instruction is defined in the same loop as the original 665d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands // instruction, or in a loop that contains it as an inner loop, then using 666d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands // it as a replacement will not break LCSSA form. 6673b0aed19f0f9ed62362c04f7e18e2ada686f4055Duncan Sands return ToLoop->contains(getLoopFor(From->getParent())); 668d0c6f3dafd7c3e9137d4e6415014c94137fcd3fcDuncan Sands } 6690bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner}; 6700bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner 671e0b6b78e095f7dea9589e8df5ec4521e346ad005Anand Shukla 6721db0a400370466e187ae06c96a1586c2c21409ddChris Lattner// Allow clients to walk the list of nested loops... 6731db0a400370466e187ae06c96a1586c2c21409ddChris Lattnertemplate <> struct GraphTraits<const Loop*> { 6741db0a400370466e187ae06c96a1586c2c21409ddChris Lattner typedef const Loop NodeType; 6759d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman typedef LoopInfo::iterator ChildIteratorType; 6761db0a400370466e187ae06c96a1586c2c21409ddChris Lattner 6771db0a400370466e187ae06c96a1586c2c21409ddChris Lattner static NodeType *getEntryNode(const Loop *L) { return L; } 6789769ab22265b313171d201b5928688524a01bd87Misha Brukman static inline ChildIteratorType child_begin(NodeType *N) { 679329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner return N->begin(); 6801db0a400370466e187ae06c96a1586c2c21409ddChris Lattner } 6819769ab22265b313171d201b5928688524a01bd87Misha Brukman static inline ChildIteratorType child_end(NodeType *N) { 682329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner return N->end(); 6831db0a400370466e187ae06c96a1586c2c21409ddChris Lattner } 6841db0a400370466e187ae06c96a1586c2c21409ddChris Lattner}; 6851db0a400370466e187ae06c96a1586c2c21409ddChris Lattner 6861db0a400370466e187ae06c96a1586c2c21409ddChris Lattnertemplate <> struct GraphTraits<Loop*> { 6871db0a400370466e187ae06c96a1586c2c21409ddChris Lattner typedef Loop NodeType; 6889d59d9f8495b0361c9ffd1dc82888d8e7ba5070eDan Gohman typedef LoopInfo::iterator ChildIteratorType; 6891db0a400370466e187ae06c96a1586c2c21409ddChris Lattner 6901db0a400370466e187ae06c96a1586c2c21409ddChris Lattner static NodeType *getEntryNode(Loop *L) { return L; } 6919769ab22265b313171d201b5928688524a01bd87Misha Brukman static inline ChildIteratorType child_begin(NodeType *N) { 692329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner return N->begin(); 6931db0a400370466e187ae06c96a1586c2c21409ddChris Lattner } 6949769ab22265b313171d201b5928688524a01bd87Misha Brukman static inline ChildIteratorType child_end(NodeType *N) { 695329c1c6c949d07e3fe9722ec633b4258217fd99dChris Lattner return N->end(); 6961db0a400370466e187ae06c96a1586c2c21409ddChris Lattner } 6971db0a400370466e187ae06c96a1586c2c21409ddChris Lattner}; 6981db0a400370466e187ae06c96a1586c2c21409ddChris Lattner 699d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke} // End llvm namespace 700d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 7010bbe58f073b4b4a6f68b3e2ee6074fc314e8d19fChris Lattner#endif 702