Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 1 | //===- MemoryDependenceAnalysis.cpp - Mem Deps Implementation --*- C++ -*-===// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
Chris Lattner | 4ee451d | 2007-12-29 20:36:04 +0000 | [diff] [blame] | 5 | // This file is distributed under the University of Illinois Open Source |
| 6 | // License. See LICENSE.TXT for details. |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | // |
| 10 | // This file implements an analysis that determines, for a given memory |
| 11 | // operation, what preceding memory operations it depends on. It builds on |
Owen Anderson | 80b1f09 | 2007-08-08 22:01:54 +0000 | [diff] [blame] | 12 | // alias analysis information, and tries to provide a lazy, caching interface to |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 13 | // a common kind of alias information query. |
| 14 | // |
| 15 | //===----------------------------------------------------------------------===// |
| 16 | |
Chris Lattner | 0e575f4 | 2008-11-28 21:45:17 +0000 | [diff] [blame] | 17 | #define DEBUG_TYPE "memdep" |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 18 | #include "llvm/Analysis/MemoryDependenceAnalysis.h" |
Owen Anderson | 7a616a1 | 2007-07-10 17:25:03 +0000 | [diff] [blame] | 19 | #include "llvm/Constants.h" |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 20 | #include "llvm/Instructions.h" |
| 21 | #include "llvm/Function.h" |
| 22 | #include "llvm/Analysis/AliasAnalysis.h" |
Chris Lattner | baad888 | 2008-11-28 22:28:27 +0000 | [diff] [blame] | 23 | #include "llvm/ADT/Statistic.h" |
Duncan Sands | 7050f3d | 2008-12-10 09:38:36 +0000 | [diff] [blame] | 24 | #include "llvm/ADT/STLExtras.h" |
Chris Lattner | 4012fdd | 2008-12-09 06:28:49 +0000 | [diff] [blame] | 25 | #include "llvm/Support/PredIteratorCache.h" |
Chris Lattner | 0e575f4 | 2008-11-28 21:45:17 +0000 | [diff] [blame] | 26 | #include "llvm/Support/Debug.h" |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 27 | #include "llvm/Target/TargetData.h" |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 28 | using namespace llvm; |
| 29 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 30 | STATISTIC(NumCacheNonLocal, "Number of fully cached non-local responses"); |
| 31 | STATISTIC(NumCacheDirtyNonLocal, "Number of dirty cached non-local responses"); |
Chris Lattner | 0ec48dd | 2008-11-29 22:02:15 +0000 | [diff] [blame] | 32 | STATISTIC(NumUncacheNonLocal, "Number of uncached non-local responses"); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 33 | |
| 34 | STATISTIC(NumCacheNonLocalPtr, |
| 35 | "Number of fully cached non-local ptr responses"); |
| 36 | STATISTIC(NumCacheDirtyNonLocalPtr, |
| 37 | "Number of cached, but dirty, non-local ptr responses"); |
| 38 | STATISTIC(NumUncacheNonLocalPtr, |
| 39 | "Number of uncached non-local ptr responses"); |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 40 | STATISTIC(NumCacheCompleteNonLocalPtr, |
| 41 | "Number of block queries that were completely cached"); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 42 | |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 43 | char MemoryDependenceAnalysis::ID = 0; |
| 44 | |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 45 | // Register this pass... |
Owen Anderson | 776ee1f | 2007-07-10 20:21:08 +0000 | [diff] [blame] | 46 | static RegisterPass<MemoryDependenceAnalysis> X("memdep", |
Chris Lattner | 0e575f4 | 2008-11-28 21:45:17 +0000 | [diff] [blame] | 47 | "Memory Dependence Analysis", false, true); |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 48 | |
Chris Lattner | 4012fdd | 2008-12-09 06:28:49 +0000 | [diff] [blame] | 49 | MemoryDependenceAnalysis::MemoryDependenceAnalysis() |
| 50 | : FunctionPass(&ID), PredCache(0) { |
| 51 | } |
| 52 | MemoryDependenceAnalysis::~MemoryDependenceAnalysis() { |
| 53 | } |
| 54 | |
| 55 | /// Clean up memory in between runs |
| 56 | void MemoryDependenceAnalysis::releaseMemory() { |
| 57 | LocalDeps.clear(); |
| 58 | NonLocalDeps.clear(); |
| 59 | NonLocalPointerDeps.clear(); |
| 60 | ReverseLocalDeps.clear(); |
| 61 | ReverseNonLocalDeps.clear(); |
| 62 | ReverseNonLocalPtrDeps.clear(); |
| 63 | PredCache->clear(); |
| 64 | } |
| 65 | |
| 66 | |
| 67 | |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 68 | /// getAnalysisUsage - Does not modify anything. It uses Alias Analysis. |
| 69 | /// |
| 70 | void MemoryDependenceAnalysis::getAnalysisUsage(AnalysisUsage &AU) const { |
| 71 | AU.setPreservesAll(); |
| 72 | AU.addRequiredTransitive<AliasAnalysis>(); |
| 73 | AU.addRequiredTransitive<TargetData>(); |
| 74 | } |
| 75 | |
Chris Lattner | d777d40 | 2008-11-30 19:24:31 +0000 | [diff] [blame] | 76 | bool MemoryDependenceAnalysis::runOnFunction(Function &) { |
| 77 | AA = &getAnalysis<AliasAnalysis>(); |
| 78 | TD = &getAnalysis<TargetData>(); |
Chris Lattner | 4012fdd | 2008-12-09 06:28:49 +0000 | [diff] [blame] | 79 | if (PredCache == 0) |
| 80 | PredCache.reset(new PredIteratorCache()); |
Chris Lattner | d777d40 | 2008-11-30 19:24:31 +0000 | [diff] [blame] | 81 | return false; |
| 82 | } |
| 83 | |
Chris Lattner | d44745d | 2008-12-07 18:39:13 +0000 | [diff] [blame] | 84 | /// RemoveFromReverseMap - This is a helper function that removes Val from |
| 85 | /// 'Inst's set in ReverseMap. If the set becomes empty, remove Inst's entry. |
| 86 | template <typename KeyTy> |
| 87 | static void RemoveFromReverseMap(DenseMap<Instruction*, |
| 88 | SmallPtrSet<KeyTy*, 4> > &ReverseMap, |
| 89 | Instruction *Inst, KeyTy *Val) { |
| 90 | typename DenseMap<Instruction*, SmallPtrSet<KeyTy*, 4> >::iterator |
| 91 | InstIt = ReverseMap.find(Inst); |
| 92 | assert(InstIt != ReverseMap.end() && "Reverse map out of sync?"); |
| 93 | bool Found = InstIt->second.erase(Val); |
| 94 | assert(Found && "Invalid reverse map!"); Found=Found; |
| 95 | if (InstIt->second.empty()) |
| 96 | ReverseMap.erase(InstIt); |
| 97 | } |
| 98 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 99 | |
Chris Lattner | 8ef57c5 | 2008-12-07 00:35:51 +0000 | [diff] [blame] | 100 | /// getCallSiteDependencyFrom - Private helper for finding the local |
| 101 | /// dependencies of a call site. |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 102 | MemDepResult MemoryDependenceAnalysis:: |
Chris Lattner | 20d6f09 | 2008-12-09 21:19:42 +0000 | [diff] [blame] | 103 | getCallSiteDependencyFrom(CallSite CS, bool isReadOnlyCall, |
| 104 | BasicBlock::iterator ScanIt, BasicBlock *BB) { |
Owen Anderson | 642a9e3 | 2007-08-08 22:26:03 +0000 | [diff] [blame] | 105 | // Walk backwards through the block, looking for dependencies |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 106 | while (ScanIt != BB->begin()) { |
| 107 | Instruction *Inst = --ScanIt; |
Owen Anderson | 5f32320 | 2007-07-10 17:59:22 +0000 | [diff] [blame] | 108 | |
| 109 | // If this inst is a memory op, get the pointer it accessed |
Chris Lattner | 00314b3 | 2008-11-29 09:15:21 +0000 | [diff] [blame] | 110 | Value *Pointer = 0; |
| 111 | uint64_t PointerSize = 0; |
| 112 | if (StoreInst *S = dyn_cast<StoreInst>(Inst)) { |
| 113 | Pointer = S->getPointerOperand(); |
Chris Lattner | d777d40 | 2008-11-30 19:24:31 +0000 | [diff] [blame] | 114 | PointerSize = TD->getTypeStoreSize(S->getOperand(0)->getType()); |
Chris Lattner | 00314b3 | 2008-11-29 09:15:21 +0000 | [diff] [blame] | 115 | } else if (VAArgInst *V = dyn_cast<VAArgInst>(Inst)) { |
| 116 | Pointer = V->getOperand(0); |
Chris Lattner | d777d40 | 2008-11-30 19:24:31 +0000 | [diff] [blame] | 117 | PointerSize = TD->getTypeStoreSize(V->getType()); |
Chris Lattner | 00314b3 | 2008-11-29 09:15:21 +0000 | [diff] [blame] | 118 | } else if (FreeInst *F = dyn_cast<FreeInst>(Inst)) { |
| 119 | Pointer = F->getPointerOperand(); |
Owen Anderson | 5f32320 | 2007-07-10 17:59:22 +0000 | [diff] [blame] | 120 | |
| 121 | // FreeInsts erase the entire structure |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 122 | PointerSize = ~0ULL; |
Chris Lattner | 00314b3 | 2008-11-29 09:15:21 +0000 | [diff] [blame] | 123 | } else if (isa<CallInst>(Inst) || isa<InvokeInst>(Inst)) { |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 124 | CallSite InstCS = CallSite::get(Inst); |
| 125 | // If these two calls do not interfere, look past it. |
Chris Lattner | 20d6f09 | 2008-12-09 21:19:42 +0000 | [diff] [blame] | 126 | switch (AA->getModRefInfo(CS, InstCS)) { |
| 127 | case AliasAnalysis::NoModRef: |
| 128 | // If the two calls don't interact (e.g. InstCS is readnone) keep |
| 129 | // scanning. |
Chris Lattner | 00314b3 | 2008-11-29 09:15:21 +0000 | [diff] [blame] | 130 | continue; |
Chris Lattner | 20d6f09 | 2008-12-09 21:19:42 +0000 | [diff] [blame] | 131 | case AliasAnalysis::Ref: |
| 132 | // If the two calls read the same memory locations and CS is a readonly |
| 133 | // function, then we have two cases: 1) the calls may not interfere with |
| 134 | // each other at all. 2) the calls may produce the same value. In case |
| 135 | // #1 we want to ignore the values, in case #2, we want to return Inst |
| 136 | // as a Def dependence. This allows us to CSE in cases like: |
| 137 | // X = strlen(P); |
| 138 | // memchr(...); |
| 139 | // Y = strlen(P); // Y = X |
| 140 | if (isReadOnlyCall) { |
| 141 | if (CS.getCalledFunction() != 0 && |
| 142 | CS.getCalledFunction() == InstCS.getCalledFunction()) |
| 143 | return MemDepResult::getDef(Inst); |
| 144 | // Ignore unrelated read/read call dependences. |
| 145 | continue; |
| 146 | } |
| 147 | // FALL THROUGH |
| 148 | default: |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 149 | return MemDepResult::getClobber(Inst); |
Chris Lattner | 20d6f09 | 2008-12-09 21:19:42 +0000 | [diff] [blame] | 150 | } |
Chris Lattner | cfbb634 | 2008-11-30 01:44:00 +0000 | [diff] [blame] | 151 | } else { |
| 152 | // Non-memory instruction. |
Owen Anderson | 202da14 | 2007-07-10 20:39:07 +0000 | [diff] [blame] | 153 | continue; |
Chris Lattner | cfbb634 | 2008-11-30 01:44:00 +0000 | [diff] [blame] | 154 | } |
Owen Anderson | 5f32320 | 2007-07-10 17:59:22 +0000 | [diff] [blame] | 155 | |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 156 | if (AA->getModRefInfo(CS, Pointer, PointerSize) != AliasAnalysis::NoModRef) |
| 157 | return MemDepResult::getClobber(Inst); |
Owen Anderson | 5f32320 | 2007-07-10 17:59:22 +0000 | [diff] [blame] | 158 | } |
| 159 | |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 160 | // No dependence found. If this is the entry block of the function, it is a |
| 161 | // clobber, otherwise it is non-local. |
| 162 | if (BB != &BB->getParent()->getEntryBlock()) |
| 163 | return MemDepResult::getNonLocal(); |
| 164 | return MemDepResult::getClobber(ScanIt); |
Owen Anderson | 5f32320 | 2007-07-10 17:59:22 +0000 | [diff] [blame] | 165 | } |
| 166 | |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 167 | /// getPointerDependencyFrom - Return the instruction on which a memory |
| 168 | /// location depends. If isLoad is true, this routine ignore may-aliases with |
| 169 | /// read-only operations. |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 170 | MemDepResult MemoryDependenceAnalysis:: |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 171 | getPointerDependencyFrom(Value *MemPtr, uint64_t MemSize, bool isLoad, |
| 172 | BasicBlock::iterator ScanIt, BasicBlock *BB) { |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 173 | |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 174 | // Walk backwards through the basic block, looking for dependencies. |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 175 | while (ScanIt != BB->begin()) { |
| 176 | Instruction *Inst = --ScanIt; |
Chris Lattner | a161ab0 | 2008-11-29 09:09:48 +0000 | [diff] [blame] | 177 | |
Chris Lattner | cfbb634 | 2008-11-30 01:44:00 +0000 | [diff] [blame] | 178 | // Values depend on loads if the pointers are must aliased. This means that |
| 179 | // a load depends on another must aliased load from the same value. |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 180 | if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) { |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 181 | Value *Pointer = LI->getPointerOperand(); |
| 182 | uint64_t PointerSize = TD->getTypeStoreSize(LI->getType()); |
| 183 | |
| 184 | // If we found a pointer, check if it could be the same as our pointer. |
Chris Lattner | a161ab0 | 2008-11-29 09:09:48 +0000 | [diff] [blame] | 185 | AliasAnalysis::AliasResult R = |
Chris Lattner | d777d40 | 2008-11-30 19:24:31 +0000 | [diff] [blame] | 186 | AA->alias(Pointer, PointerSize, MemPtr, MemSize); |
Chris Lattner | a161ab0 | 2008-11-29 09:09:48 +0000 | [diff] [blame] | 187 | if (R == AliasAnalysis::NoAlias) |
| 188 | continue; |
| 189 | |
| 190 | // May-alias loads don't depend on each other without a dependence. |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 191 | if (isLoad && R == AliasAnalysis::MayAlias) |
Chris Lattner | a161ab0 | 2008-11-29 09:09:48 +0000 | [diff] [blame] | 192 | continue; |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 193 | // Stores depend on may and must aliased loads, loads depend on must-alias |
| 194 | // loads. |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 195 | return MemDepResult::getDef(Inst); |
| 196 | } |
| 197 | |
| 198 | if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) { |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 199 | Value *Pointer = SI->getPointerOperand(); |
| 200 | uint64_t PointerSize = TD->getTypeStoreSize(SI->getOperand(0)->getType()); |
| 201 | |
| 202 | // If we found a pointer, check if it could be the same as our pointer. |
| 203 | AliasAnalysis::AliasResult R = |
| 204 | AA->alias(Pointer, PointerSize, MemPtr, MemSize); |
| 205 | |
| 206 | if (R == AliasAnalysis::NoAlias) |
| 207 | continue; |
| 208 | if (R == AliasAnalysis::MayAlias) |
| 209 | return MemDepResult::getClobber(Inst); |
| 210 | return MemDepResult::getDef(Inst); |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 211 | } |
Chris Lattner | 237a828 | 2008-11-30 01:39:32 +0000 | [diff] [blame] | 212 | |
| 213 | // If this is an allocation, and if we know that the accessed pointer is to |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 214 | // the allocation, return Def. This means that there is no dependence and |
Chris Lattner | 237a828 | 2008-11-30 01:39:32 +0000 | [diff] [blame] | 215 | // the access can be optimized based on that. For example, a load could |
| 216 | // turn into undef. |
Chris Lattner | a161ab0 | 2008-11-29 09:09:48 +0000 | [diff] [blame] | 217 | if (AllocationInst *AI = dyn_cast<AllocationInst>(Inst)) { |
Chris Lattner | 237a828 | 2008-11-30 01:39:32 +0000 | [diff] [blame] | 218 | Value *AccessPtr = MemPtr->getUnderlyingObject(); |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 219 | |
Chris Lattner | 237a828 | 2008-11-30 01:39:32 +0000 | [diff] [blame] | 220 | if (AccessPtr == AI || |
Chris Lattner | d777d40 | 2008-11-30 19:24:31 +0000 | [diff] [blame] | 221 | AA->alias(AI, 1, AccessPtr, 1) == AliasAnalysis::MustAlias) |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 222 | return MemDepResult::getDef(AI); |
Chris Lattner | 237a828 | 2008-11-30 01:39:32 +0000 | [diff] [blame] | 223 | continue; |
Chris Lattner | a161ab0 | 2008-11-29 09:09:48 +0000 | [diff] [blame] | 224 | } |
Chris Lattner | a161ab0 | 2008-11-29 09:09:48 +0000 | [diff] [blame] | 225 | |
Chris Lattner | b51deb9 | 2008-12-05 21:04:20 +0000 | [diff] [blame] | 226 | // See if this instruction (e.g. a call or vaarg) mod/ref's the pointer. |
Chris Lattner | 3579e44 | 2008-12-09 19:47:40 +0000 | [diff] [blame] | 227 | switch (AA->getModRefInfo(Inst, MemPtr, MemSize)) { |
| 228 | case AliasAnalysis::NoModRef: |
| 229 | // If the call has no effect on the queried pointer, just ignore it. |
Chris Lattner | 25a0814 | 2008-11-29 08:51:16 +0000 | [diff] [blame] | 230 | continue; |
Chris Lattner | 3579e44 | 2008-12-09 19:47:40 +0000 | [diff] [blame] | 231 | case AliasAnalysis::Ref: |
| 232 | // If the call is known to never store to the pointer, and if this is a |
| 233 | // load query, we can safely ignore it (scan past it). |
| 234 | if (isLoad) |
| 235 | continue; |
| 236 | // FALL THROUGH. |
| 237 | default: |
| 238 | // Otherwise, there is a potential dependence. Return a clobber. |
| 239 | return MemDepResult::getClobber(Inst); |
| 240 | } |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 241 | } |
| 242 | |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 243 | // No dependence found. If this is the entry block of the function, it is a |
| 244 | // clobber, otherwise it is non-local. |
| 245 | if (BB != &BB->getParent()->getEntryBlock()) |
| 246 | return MemDepResult::getNonLocal(); |
| 247 | return MemDepResult::getClobber(ScanIt); |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 248 | } |
| 249 | |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 250 | /// getDependency - Return the instruction on which a memory operation |
| 251 | /// depends. |
| 252 | MemDepResult MemoryDependenceAnalysis::getDependency(Instruction *QueryInst) { |
| 253 | Instruction *ScanPos = QueryInst; |
| 254 | |
| 255 | // Check for a cached result |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 256 | MemDepResult &LocalCache = LocalDeps[QueryInst]; |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 257 | |
Chris Lattner | 0ec48dd | 2008-11-29 22:02:15 +0000 | [diff] [blame] | 258 | // If the cached entry is non-dirty, just return it. Note that this depends |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 259 | // on MemDepResult's default constructing to 'dirty'. |
| 260 | if (!LocalCache.isDirty()) |
| 261 | return LocalCache; |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 262 | |
| 263 | // Otherwise, if we have a dirty entry, we know we can start the scan at that |
| 264 | // instruction, which may save us some work. |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 265 | if (Instruction *Inst = LocalCache.getInst()) { |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 266 | ScanPos = Inst; |
Chris Lattner | 4a69bad | 2008-11-30 02:52:26 +0000 | [diff] [blame] | 267 | |
Chris Lattner | d44745d | 2008-12-07 18:39:13 +0000 | [diff] [blame] | 268 | RemoveFromReverseMap(ReverseLocalDeps, Inst, QueryInst); |
Chris Lattner | 4a69bad | 2008-11-30 02:52:26 +0000 | [diff] [blame] | 269 | } |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 270 | |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 271 | BasicBlock *QueryParent = QueryInst->getParent(); |
| 272 | |
| 273 | Value *MemPtr = 0; |
| 274 | uint64_t MemSize = 0; |
| 275 | |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 276 | // Do the scan. |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 277 | if (BasicBlock::iterator(QueryInst) == QueryParent->begin()) { |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 278 | // No dependence found. If this is the entry block of the function, it is a |
| 279 | // clobber, otherwise it is non-local. |
| 280 | if (QueryParent != &QueryParent->getParent()->getEntryBlock()) |
| 281 | LocalCache = MemDepResult::getNonLocal(); |
| 282 | else |
| 283 | LocalCache = MemDepResult::getClobber(QueryInst); |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 284 | } else if (StoreInst *SI = dyn_cast<StoreInst>(QueryInst)) { |
| 285 | // If this is a volatile store, don't mess around with it. Just return the |
| 286 | // previous instruction as a clobber. |
| 287 | if (SI->isVolatile()) |
| 288 | LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos)); |
| 289 | else { |
| 290 | MemPtr = SI->getPointerOperand(); |
| 291 | MemSize = TD->getTypeStoreSize(SI->getOperand(0)->getType()); |
| 292 | } |
| 293 | } else if (LoadInst *LI = dyn_cast<LoadInst>(QueryInst)) { |
| 294 | // If this is a volatile load, don't mess around with it. Just return the |
| 295 | // previous instruction as a clobber. |
| 296 | if (LI->isVolatile()) |
| 297 | LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos)); |
| 298 | else { |
| 299 | MemPtr = LI->getPointerOperand(); |
| 300 | MemSize = TD->getTypeStoreSize(LI->getType()); |
| 301 | } |
| 302 | } else if (isa<CallInst>(QueryInst) || isa<InvokeInst>(QueryInst)) { |
Chris Lattner | 20d6f09 | 2008-12-09 21:19:42 +0000 | [diff] [blame] | 303 | CallSite QueryCS = CallSite::get(QueryInst); |
| 304 | bool isReadOnly = AA->onlyReadsMemory(QueryCS); |
| 305 | LocalCache = getCallSiteDependencyFrom(QueryCS, isReadOnly, ScanPos, |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 306 | QueryParent); |
| 307 | } else if (FreeInst *FI = dyn_cast<FreeInst>(QueryInst)) { |
| 308 | MemPtr = FI->getPointerOperand(); |
| 309 | // FreeInsts erase the entire structure, not just a field. |
| 310 | MemSize = ~0UL; |
| 311 | } else { |
| 312 | // Non-memory instruction. |
| 313 | LocalCache = MemDepResult::getClobber(--BasicBlock::iterator(ScanPos)); |
| 314 | } |
| 315 | |
| 316 | // If we need to do a pointer scan, make it happen. |
| 317 | if (MemPtr) |
| 318 | LocalCache = getPointerDependencyFrom(MemPtr, MemSize, |
| 319 | isa<LoadInst>(QueryInst), |
| 320 | ScanPos, QueryParent); |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 321 | |
| 322 | // Remember the result! |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 323 | if (Instruction *I = LocalCache.getInst()) |
Chris Lattner | 8c46527 | 2008-11-29 09:20:15 +0000 | [diff] [blame] | 324 | ReverseLocalDeps[I].insert(QueryInst); |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 325 | |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 326 | return LocalCache; |
Chris Lattner | 5391a1d | 2008-11-29 03:47:00 +0000 | [diff] [blame] | 327 | } |
| 328 | |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 329 | #ifndef NDEBUG |
| 330 | /// AssertSorted - This method is used when -debug is specified to verify that |
| 331 | /// cache arrays are properly kept sorted. |
| 332 | static void AssertSorted(MemoryDependenceAnalysis::NonLocalDepInfo &Cache, |
| 333 | int Count = -1) { |
| 334 | if (Count == -1) Count = Cache.size(); |
| 335 | if (Count == 0) return; |
| 336 | |
| 337 | for (unsigned i = 1; i != unsigned(Count); ++i) |
| 338 | assert(Cache[i-1] <= Cache[i] && "Cache isn't sorted!"); |
| 339 | } |
| 340 | #endif |
| 341 | |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 342 | /// getNonLocalCallDependency - Perform a full dependency query for the |
| 343 | /// specified call, returning the set of blocks that the value is |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 344 | /// potentially live across. The returned set of results will include a |
| 345 | /// "NonLocal" result for all blocks where the value is live across. |
| 346 | /// |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 347 | /// This method assumes the instruction returns a "NonLocal" dependency |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 348 | /// within its own block. |
| 349 | /// |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 350 | /// This returns a reference to an internal data structure that may be |
| 351 | /// invalidated on the next non-local query or when an instruction is |
| 352 | /// removed. Clients must copy this data if they want it around longer than |
| 353 | /// that. |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 354 | const MemoryDependenceAnalysis::NonLocalDepInfo & |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 355 | MemoryDependenceAnalysis::getNonLocalCallDependency(CallSite QueryCS) { |
| 356 | assert(getDependency(QueryCS.getInstruction()).isNonLocal() && |
| 357 | "getNonLocalCallDependency should only be used on calls with non-local deps!"); |
| 358 | PerInstNLInfo &CacheP = NonLocalDeps[QueryCS.getInstruction()]; |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 359 | NonLocalDepInfo &Cache = CacheP.first; |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 360 | |
| 361 | /// DirtyBlocks - This is the set of blocks that need to be recomputed. In |
| 362 | /// the cached case, this can happen due to instructions being deleted etc. In |
| 363 | /// the uncached case, this starts out as the set of predecessors we care |
| 364 | /// about. |
| 365 | SmallVector<BasicBlock*, 32> DirtyBlocks; |
| 366 | |
| 367 | if (!Cache.empty()) { |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 368 | // Okay, we have a cache entry. If we know it is not dirty, just return it |
| 369 | // with no computation. |
| 370 | if (!CacheP.second) { |
| 371 | NumCacheNonLocal++; |
| 372 | return Cache; |
| 373 | } |
| 374 | |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 375 | // If we already have a partially computed set of results, scan them to |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 376 | // determine what is dirty, seeding our initial DirtyBlocks worklist. |
| 377 | for (NonLocalDepInfo::iterator I = Cache.begin(), E = Cache.end(); |
| 378 | I != E; ++I) |
| 379 | if (I->second.isDirty()) |
| 380 | DirtyBlocks.push_back(I->first); |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 381 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 382 | // Sort the cache so that we can do fast binary search lookups below. |
| 383 | std::sort(Cache.begin(), Cache.end()); |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 384 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 385 | ++NumCacheDirtyNonLocal; |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 386 | //cerr << "CACHED CASE: " << DirtyBlocks.size() << " dirty: " |
| 387 | // << Cache.size() << " cached: " << *QueryInst; |
| 388 | } else { |
| 389 | // Seed DirtyBlocks with each of the preds of QueryInst's block. |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 390 | BasicBlock *QueryBB = QueryCS.getInstruction()->getParent(); |
Chris Lattner | 511b36c | 2008-12-09 06:44:17 +0000 | [diff] [blame] | 391 | for (BasicBlock **PI = PredCache->GetPreds(QueryBB); *PI; ++PI) |
| 392 | DirtyBlocks.push_back(*PI); |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 393 | NumUncacheNonLocal++; |
| 394 | } |
| 395 | |
Chris Lattner | 20d6f09 | 2008-12-09 21:19:42 +0000 | [diff] [blame] | 396 | // isReadonlyCall - If this is a read-only call, we can be more aggressive. |
| 397 | bool isReadonlyCall = AA->onlyReadsMemory(QueryCS); |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 398 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 399 | SmallPtrSet<BasicBlock*, 64> Visited; |
| 400 | |
| 401 | unsigned NumSortedEntries = Cache.size(); |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 402 | DEBUG(AssertSorted(Cache)); |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 403 | |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 404 | // Iterate while we still have blocks to update. |
| 405 | while (!DirtyBlocks.empty()) { |
| 406 | BasicBlock *DirtyBB = DirtyBlocks.back(); |
| 407 | DirtyBlocks.pop_back(); |
| 408 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 409 | // Already processed this block? |
| 410 | if (!Visited.insert(DirtyBB)) |
| 411 | continue; |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 412 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 413 | // Do a binary search to see if we already have an entry for this block in |
| 414 | // the cache set. If so, find it. |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 415 | DEBUG(AssertSorted(Cache, NumSortedEntries)); |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 416 | NonLocalDepInfo::iterator Entry = |
| 417 | std::upper_bound(Cache.begin(), Cache.begin()+NumSortedEntries, |
| 418 | std::make_pair(DirtyBB, MemDepResult())); |
Duncan Sands | 7050f3d | 2008-12-10 09:38:36 +0000 | [diff] [blame] | 419 | if (Entry != Cache.begin() && prior(Entry)->first == DirtyBB) |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 420 | --Entry; |
| 421 | |
| 422 | MemDepResult *ExistingResult = 0; |
| 423 | if (Entry != Cache.begin()+NumSortedEntries && |
| 424 | Entry->first == DirtyBB) { |
| 425 | // If we already have an entry, and if it isn't already dirty, the block |
| 426 | // is done. |
| 427 | if (!Entry->second.isDirty()) |
| 428 | continue; |
| 429 | |
| 430 | // Otherwise, remember this slot so we can update the value. |
| 431 | ExistingResult = &Entry->second; |
| 432 | } |
| 433 | |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 434 | // If the dirty entry has a pointer, start scanning from it so we don't have |
| 435 | // to rescan the entire block. |
| 436 | BasicBlock::iterator ScanPos = DirtyBB->end(); |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 437 | if (ExistingResult) { |
| 438 | if (Instruction *Inst = ExistingResult->getInst()) { |
| 439 | ScanPos = Inst; |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 440 | // We're removing QueryInst's use of Inst. |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 441 | RemoveFromReverseMap(ReverseNonLocalDeps, Inst, |
| 442 | QueryCS.getInstruction()); |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 443 | } |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 444 | } |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 445 | |
Chris Lattner | 73ec3cd | 2008-11-30 01:26:32 +0000 | [diff] [blame] | 446 | // Find out if this block has a local dependency for QueryInst. |
Chris Lattner | d8dd934 | 2008-12-07 01:21:14 +0000 | [diff] [blame] | 447 | MemDepResult Dep; |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 448 | |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 449 | if (ScanPos != DirtyBB->begin()) { |
Chris Lattner | 20d6f09 | 2008-12-09 21:19:42 +0000 | [diff] [blame] | 450 | Dep = getCallSiteDependencyFrom(QueryCS, isReadonlyCall,ScanPos, DirtyBB); |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 451 | } else if (DirtyBB != &DirtyBB->getParent()->getEntryBlock()) { |
| 452 | // No dependence found. If this is the entry block of the function, it is |
| 453 | // a clobber, otherwise it is non-local. |
| 454 | Dep = MemDepResult::getNonLocal(); |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 455 | } else { |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 456 | Dep = MemDepResult::getClobber(ScanPos); |
Chris Lattner | e79be94 | 2008-12-07 01:50:16 +0000 | [diff] [blame] | 457 | } |
| 458 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 459 | // If we had a dirty entry for the block, update it. Otherwise, just add |
| 460 | // a new entry. |
| 461 | if (ExistingResult) |
| 462 | *ExistingResult = Dep; |
| 463 | else |
| 464 | Cache.push_back(std::make_pair(DirtyBB, Dep)); |
| 465 | |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 466 | // If the block has a dependency (i.e. it isn't completely transparent to |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 467 | // the value), remember the association! |
| 468 | if (!Dep.isNonLocal()) { |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 469 | // Keep the ReverseNonLocalDeps map up to date so we can efficiently |
| 470 | // update this when we remove instructions. |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 471 | if (Instruction *Inst = Dep.getInst()) |
Chris Lattner | 1559b36 | 2008-12-09 19:38:05 +0000 | [diff] [blame] | 472 | ReverseNonLocalDeps[Inst].insert(QueryCS.getInstruction()); |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 473 | } else { |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 474 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 475 | // If the block *is* completely transparent to the load, we need to check |
| 476 | // the predecessors of this block. Add them to our worklist. |
Chris Lattner | 511b36c | 2008-12-09 06:44:17 +0000 | [diff] [blame] | 477 | for (BasicBlock **PI = PredCache->GetPreds(DirtyBB); *PI; ++PI) |
| 478 | DirtyBlocks.push_back(*PI); |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 479 | } |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 480 | } |
| 481 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 482 | return Cache; |
Chris Lattner | 37d041c | 2008-11-30 01:18:27 +0000 | [diff] [blame] | 483 | } |
| 484 | |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 485 | /// getNonLocalPointerDependency - Perform a full dependency query for an |
| 486 | /// access to the specified (non-volatile) memory location, returning the |
| 487 | /// set of instructions that either define or clobber the value. |
| 488 | /// |
| 489 | /// This method assumes the pointer has a "NonLocal" dependency within its |
| 490 | /// own block. |
| 491 | /// |
| 492 | void MemoryDependenceAnalysis:: |
| 493 | getNonLocalPointerDependency(Value *Pointer, bool isLoad, BasicBlock *FromBB, |
| 494 | SmallVectorImpl<NonLocalDepEntry> &Result) { |
Chris Lattner | 3f7eb5b | 2008-12-07 18:45:15 +0000 | [diff] [blame] | 495 | assert(isa<PointerType>(Pointer->getType()) && |
| 496 | "Can't get pointer deps of a non-pointer!"); |
Chris Lattner | 9a193fd | 2008-12-07 02:56:57 +0000 | [diff] [blame] | 497 | Result.clear(); |
| 498 | |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 499 | // We know that the pointer value is live into FromBB find the def/clobbers |
| 500 | // from presecessors. |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 501 | const Type *EltTy = cast<PointerType>(Pointer->getType())->getElementType(); |
| 502 | uint64_t PointeeSize = TD->getTypeStoreSize(EltTy); |
| 503 | |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 504 | // This is the set of blocks we've inspected, and the pointer we consider in |
| 505 | // each block. Because of critical edges, we currently bail out if querying |
| 506 | // a block with multiple different pointers. This can happen during PHI |
| 507 | // translation. |
| 508 | DenseMap<BasicBlock*, Value*> Visited; |
| 509 | if (!getNonLocalPointerDepFromBB(Pointer, PointeeSize, isLoad, FromBB, |
| 510 | Result, Visited, true)) |
| 511 | return; |
Chris Lattner | 3af23f8 | 2008-12-15 04:58:29 +0000 | [diff] [blame] | 512 | Result.clear(); |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 513 | Result.push_back(std::make_pair(FromBB, |
| 514 | MemDepResult::getClobber(FromBB->begin()))); |
Chris Lattner | 9a193fd | 2008-12-07 02:56:57 +0000 | [diff] [blame] | 515 | } |
| 516 | |
Chris Lattner | 9863c3f | 2008-12-09 07:47:11 +0000 | [diff] [blame] | 517 | /// GetNonLocalInfoForBlock - Compute the memdep value for BB with |
| 518 | /// Pointer/PointeeSize using either cached information in Cache or by doing a |
| 519 | /// lookup (which may use dirty cache info if available). If we do a lookup, |
| 520 | /// add the result to the cache. |
| 521 | MemDepResult MemoryDependenceAnalysis:: |
| 522 | GetNonLocalInfoForBlock(Value *Pointer, uint64_t PointeeSize, |
| 523 | bool isLoad, BasicBlock *BB, |
| 524 | NonLocalDepInfo *Cache, unsigned NumSortedEntries) { |
| 525 | |
| 526 | // Do a binary search to see if we already have an entry for this block in |
| 527 | // the cache set. If so, find it. |
| 528 | NonLocalDepInfo::iterator Entry = |
| 529 | std::upper_bound(Cache->begin(), Cache->begin()+NumSortedEntries, |
| 530 | std::make_pair(BB, MemDepResult())); |
Duncan Sands | 7050f3d | 2008-12-10 09:38:36 +0000 | [diff] [blame] | 531 | if (Entry != Cache->begin() && prior(Entry)->first == BB) |
Chris Lattner | 9863c3f | 2008-12-09 07:47:11 +0000 | [diff] [blame] | 532 | --Entry; |
| 533 | |
| 534 | MemDepResult *ExistingResult = 0; |
| 535 | if (Entry != Cache->begin()+NumSortedEntries && Entry->first == BB) |
| 536 | ExistingResult = &Entry->second; |
| 537 | |
| 538 | // If we have a cached entry, and it is non-dirty, use it as the value for |
| 539 | // this dependency. |
| 540 | if (ExistingResult && !ExistingResult->isDirty()) { |
| 541 | ++NumCacheNonLocalPtr; |
| 542 | return *ExistingResult; |
| 543 | } |
| 544 | |
| 545 | // Otherwise, we have to scan for the value. If we have a dirty cache |
| 546 | // entry, start scanning from its position, otherwise we scan from the end |
| 547 | // of the block. |
| 548 | BasicBlock::iterator ScanPos = BB->end(); |
| 549 | if (ExistingResult && ExistingResult->getInst()) { |
| 550 | assert(ExistingResult->getInst()->getParent() == BB && |
| 551 | "Instruction invalidated?"); |
| 552 | ++NumCacheDirtyNonLocalPtr; |
| 553 | ScanPos = ExistingResult->getInst(); |
| 554 | |
| 555 | // Eliminating the dirty entry from 'Cache', so update the reverse info. |
| 556 | ValueIsLoadPair CacheKey(Pointer, isLoad); |
| 557 | RemoveFromReverseMap(ReverseNonLocalPtrDeps, ScanPos, |
| 558 | CacheKey.getOpaqueValue()); |
| 559 | } else { |
| 560 | ++NumUncacheNonLocalPtr; |
| 561 | } |
| 562 | |
| 563 | // Scan the block for the dependency. |
| 564 | MemDepResult Dep = getPointerDependencyFrom(Pointer, PointeeSize, isLoad, |
| 565 | ScanPos, BB); |
| 566 | |
| 567 | // If we had a dirty entry for the block, update it. Otherwise, just add |
| 568 | // a new entry. |
| 569 | if (ExistingResult) |
| 570 | *ExistingResult = Dep; |
| 571 | else |
| 572 | Cache->push_back(std::make_pair(BB, Dep)); |
| 573 | |
| 574 | // If the block has a dependency (i.e. it isn't completely transparent to |
| 575 | // the value), remember the reverse association because we just added it |
| 576 | // to Cache! |
| 577 | if (Dep.isNonLocal()) |
| 578 | return Dep; |
| 579 | |
| 580 | // Keep the ReverseNonLocalPtrDeps map up to date so we can efficiently |
| 581 | // update MemDep when we remove instructions. |
| 582 | Instruction *Inst = Dep.getInst(); |
| 583 | assert(Inst && "Didn't depend on anything?"); |
| 584 | ValueIsLoadPair CacheKey(Pointer, isLoad); |
| 585 | ReverseNonLocalPtrDeps[Inst].insert(CacheKey.getOpaqueValue()); |
| 586 | return Dep; |
| 587 | } |
| 588 | |
| 589 | |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 590 | /// getNonLocalPointerDepFromBB - Perform a dependency query based on |
| 591 | /// pointer/pointeesize starting at the end of StartBB. Add any clobber/def |
| 592 | /// results to the results vector and keep track of which blocks are visited in |
| 593 | /// 'Visited'. |
| 594 | /// |
| 595 | /// This has special behavior for the first block queries (when SkipFirstBlock |
| 596 | /// is true). In this special case, it ignores the contents of the specified |
| 597 | /// block and starts returning dependence info for its predecessors. |
| 598 | /// |
| 599 | /// This function returns false on success, or true to indicate that it could |
| 600 | /// not compute dependence information for some reason. This should be treated |
| 601 | /// as a clobber dependence on the first instruction in the predecessor block. |
| 602 | bool MemoryDependenceAnalysis:: |
Chris Lattner | 9863c3f | 2008-12-09 07:47:11 +0000 | [diff] [blame] | 603 | getNonLocalPointerDepFromBB(Value *Pointer, uint64_t PointeeSize, |
| 604 | bool isLoad, BasicBlock *StartBB, |
| 605 | SmallVectorImpl<NonLocalDepEntry> &Result, |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 606 | DenseMap<BasicBlock*, Value*> &Visited, |
| 607 | bool SkipFirstBlock) { |
| 608 | |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 609 | // Look up the cached info for Pointer. |
| 610 | ValueIsLoadPair CacheKey(Pointer, isLoad); |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 611 | |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 612 | std::pair<BBSkipFirstBlockPair, NonLocalDepInfo> *CacheInfo = |
| 613 | &NonLocalPointerDeps[CacheKey]; |
| 614 | NonLocalDepInfo *Cache = &CacheInfo->second; |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 615 | |
| 616 | // If we have valid cached information for exactly the block we are |
| 617 | // investigating, just return it with no recomputation. |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 618 | if (CacheInfo->first == BBSkipFirstBlockPair(StartBB, SkipFirstBlock)) { |
Chris Lattner | f478951 | 2008-12-16 07:10:09 +0000 | [diff] [blame] | 619 | // We have a fully cached result for this query then we can just return the |
| 620 | // cached results and populate the visited set. However, we have to verify |
| 621 | // that we don't already have conflicting results for these blocks. Check |
| 622 | // to ensure that if a block in the results set is in the visited set that |
| 623 | // it was for the same pointer query. |
| 624 | if (!Visited.empty()) { |
| 625 | for (NonLocalDepInfo::iterator I = Cache->begin(), E = Cache->end(); |
| 626 | I != E; ++I) { |
| 627 | DenseMap<BasicBlock*, Value*>::iterator VI = Visited.find(I->first); |
| 628 | if (VI == Visited.end() || VI->second == Pointer) continue; |
| 629 | |
| 630 | // We have a pointer mismatch in a block. Just return clobber, saying |
| 631 | // that something was clobbered in this result. We could also do a |
| 632 | // non-fully cached query, but there is little point in doing this. |
| 633 | return true; |
| 634 | } |
| 635 | } |
| 636 | |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 637 | for (NonLocalDepInfo::iterator I = Cache->begin(), E = Cache->end(); |
Chris Lattner | f478951 | 2008-12-16 07:10:09 +0000 | [diff] [blame] | 638 | I != E; ++I) { |
| 639 | Visited.insert(std::make_pair(I->first, Pointer)); |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 640 | if (!I->second.isNonLocal()) |
| 641 | Result.push_back(*I); |
Chris Lattner | f478951 | 2008-12-16 07:10:09 +0000 | [diff] [blame] | 642 | } |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 643 | ++NumCacheCompleteNonLocalPtr; |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 644 | return false; |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 645 | } |
| 646 | |
| 647 | // Otherwise, either this is a new block, a block with an invalid cache |
| 648 | // pointer or one that we're about to invalidate by putting more info into it |
| 649 | // than its valid cache info. If empty, the result will be valid cache info, |
| 650 | // otherwise it isn't. |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 651 | if (Cache->empty()) |
| 652 | CacheInfo->first = BBSkipFirstBlockPair(StartBB, SkipFirstBlock); |
| 653 | else |
| 654 | CacheInfo->first = BBSkipFirstBlockPair(); |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 655 | |
| 656 | SmallVector<BasicBlock*, 32> Worklist; |
| 657 | Worklist.push_back(StartBB); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 658 | |
| 659 | // Keep track of the entries that we know are sorted. Previously cached |
| 660 | // entries will all be sorted. The entries we add we only sort on demand (we |
| 661 | // don't insert every element into its sorted position). We know that we |
| 662 | // won't get any reuse from currently inserted values, because we don't |
| 663 | // revisit blocks after we insert info for them. |
| 664 | unsigned NumSortedEntries = Cache->size(); |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 665 | DEBUG(AssertSorted(*Cache)); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 666 | |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 667 | while (!Worklist.empty()) { |
Chris Lattner | 9a193fd | 2008-12-07 02:56:57 +0000 | [diff] [blame] | 668 | BasicBlock *BB = Worklist.pop_back_val(); |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 669 | |
Chris Lattner | 6563371 | 2008-12-09 07:52:59 +0000 | [diff] [blame] | 670 | // Skip the first block if we have it. |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 671 | if (!SkipFirstBlock) { |
Chris Lattner | 6563371 | 2008-12-09 07:52:59 +0000 | [diff] [blame] | 672 | // Analyze the dependency of *Pointer in FromBB. See if we already have |
| 673 | // been here. |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 674 | assert(Visited.count(BB) && "Should check 'visited' before adding to WL"); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 675 | |
Chris Lattner | 6563371 | 2008-12-09 07:52:59 +0000 | [diff] [blame] | 676 | // Get the dependency info for Pointer in BB. If we have cached |
| 677 | // information, we will use it, otherwise we compute it. |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 678 | DEBUG(AssertSorted(*Cache, NumSortedEntries)); |
Chris Lattner | 6563371 | 2008-12-09 07:52:59 +0000 | [diff] [blame] | 679 | MemDepResult Dep = GetNonLocalInfoForBlock(Pointer, PointeeSize, isLoad, |
| 680 | BB, Cache, NumSortedEntries); |
| 681 | |
| 682 | // If we got a Def or Clobber, add this to the list of results. |
| 683 | if (!Dep.isNonLocal()) { |
| 684 | Result.push_back(NonLocalDepEntry(BB, Dep)); |
| 685 | continue; |
| 686 | } |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 687 | } |
| 688 | |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 689 | // If 'Pointer' is an instruction defined in this block, then we need to do |
| 690 | // phi translation to change it into a value live in the predecessor block. |
| 691 | // If phi translation fails, then we can't continue dependence analysis. |
| 692 | Instruction *PtrInst = dyn_cast<Instruction>(Pointer); |
| 693 | bool NeedsPHITranslation = PtrInst && PtrInst->getParent() == BB; |
| 694 | |
| 695 | // If no PHI translation is needed, just add all the predecessors of this |
| 696 | // block to scan them as well. |
| 697 | if (!NeedsPHITranslation) { |
| 698 | SkipFirstBlock = false; |
| 699 | for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) { |
| 700 | // Verify that we haven't looked at this block yet. |
| 701 | std::pair<DenseMap<BasicBlock*,Value*>::iterator, bool> |
| 702 | InsertRes = Visited.insert(std::make_pair(*PI, Pointer)); |
| 703 | if (InsertRes.second) { |
| 704 | // First time we've looked at *PI. |
| 705 | Worklist.push_back(*PI); |
| 706 | continue; |
| 707 | } |
| 708 | |
| 709 | // If we have seen this block before, but it was with a different |
| 710 | // pointer then we have a phi translation failure and we have to treat |
| 711 | // this as a clobber. |
| 712 | if (InsertRes.first->second != Pointer) |
| 713 | goto PredTranslationFailure; |
| 714 | } |
| 715 | continue; |
| 716 | } |
| 717 | |
| 718 | // If we do need to do phi translation, then there are a bunch of different |
| 719 | // cases, because we have to find a Value* live in the predecessor block. We |
| 720 | // know that PtrInst is defined in this block at least. |
| 721 | |
| 722 | // If this is directly a PHI node, just use the incoming values for each |
| 723 | // pred as the phi translated version. |
| 724 | if (PHINode *PtrPHI = dyn_cast<PHINode>(PtrInst)) { |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 725 | for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) { |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 726 | BasicBlock *Pred = *PI; |
| 727 | Value *PredPtr = PtrPHI->getIncomingValueForBlock(Pred); |
| 728 | |
| 729 | // Check to see if we have already visited this pred block with another |
| 730 | // pointer. If so, we can't do this lookup. This failure can occur |
| 731 | // with PHI translation when a critical edge exists and the PHI node in |
| 732 | // the successor translates to a pointer value different than the |
| 733 | // pointer the block was first analyzed with. |
| 734 | std::pair<DenseMap<BasicBlock*,Value*>::iterator, bool> |
| 735 | InsertRes = Visited.insert(std::make_pair(Pred, PredPtr)); |
| 736 | |
| 737 | if (!InsertRes.second) { |
| 738 | // If the predecessor was visited with PredPtr, then we already did |
| 739 | // the analysis and can ignore it. |
| 740 | if (InsertRes.first->second == PredPtr) |
| 741 | continue; |
| 742 | |
| 743 | // Otherwise, the block was previously analyzed with a different |
| 744 | // pointer. We can't represent the result of this case, so we just |
| 745 | // treat this as a phi translation failure. |
| 746 | goto PredTranslationFailure; |
| 747 | } |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 748 | |
| 749 | // We may have added values to the cache list before this PHI |
| 750 | // translation. If so, we haven't done anything to ensure that the |
| 751 | // cache remains sorted. Sort it now (if needed) so that recursive |
| 752 | // invocations of getNonLocalPointerDepFromBB that could reuse the cache |
| 753 | // value will only see properly sorted cache arrays. |
Chris Lattner | 4433a09 | 2009-01-23 06:48:41 +0000 | [diff] [blame] | 754 | if (Cache && NumSortedEntries != Cache->size()) |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 755 | std::sort(Cache->begin(), Cache->end()); |
Chris Lattner | 4433a09 | 2009-01-23 06:48:41 +0000 | [diff] [blame] | 756 | Cache = 0; |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 757 | |
| 758 | // FIXME: it is entirely possible that PHI translating will end up with |
| 759 | // the same value. Consider PHI translating something like: |
| 760 | // X = phi [x, bb1], [y, bb2]. PHI translating for bb1 doesn't *need* |
| 761 | // to recurse here, pedantically speaking. |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 762 | |
| 763 | // If we have a problem phi translating, fall through to the code below |
| 764 | // to handle the failure condition. |
| 765 | if (getNonLocalPointerDepFromBB(PredPtr, PointeeSize, isLoad, Pred, |
| 766 | Result, Visited)) |
| 767 | goto PredTranslationFailure; |
| 768 | } |
Chris Lattner | b54bfc2 | 2009-01-23 00:27:03 +0000 | [diff] [blame] | 769 | |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 770 | // Refresh the CacheInfo/Cache pointer so that it isn't invalidated. |
| 771 | CacheInfo = &NonLocalPointerDeps[CacheKey]; |
| 772 | Cache = &CacheInfo->second; |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 773 | NumSortedEntries = Cache->size(); |
Chris Lattner | b54bfc2 | 2009-01-23 00:27:03 +0000 | [diff] [blame] | 774 | |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 775 | // Since we did phi translation, the "Cache" set won't contain all of the |
| 776 | // results for the query. This is ok (we can still use it to accelerate |
| 777 | // specific block queries) but we can't do the fastpath "return all |
| 778 | // results from the set" Clear out the indicator for this. |
| 779 | CacheInfo->first = BBSkipFirstBlockPair(); |
| 780 | SkipFirstBlock = false; |
| 781 | continue; |
| 782 | } |
| 783 | |
| 784 | // TODO: BITCAST, GEP. |
| 785 | |
| 786 | // cerr << "MEMDEP: Could not PHI translate: " << *Pointer; |
| 787 | // if (isa<BitCastInst>(PtrInst) || isa<GetElementPtrInst>(PtrInst)) |
| 788 | // cerr << "OP:\t\t\t\t" << *PtrInst->getOperand(0); |
| 789 | PredTranslationFailure: |
| 790 | |
Chris Lattner | 95900f2 | 2009-01-23 07:12:16 +0000 | [diff] [blame^] | 791 | if (Cache == 0) { |
| 792 | // Refresh the CacheInfo/Cache pointer if it got invalidated. |
| 793 | CacheInfo = &NonLocalPointerDeps[CacheKey]; |
| 794 | Cache = &CacheInfo->second; |
| 795 | NumSortedEntries = Cache->size(); |
| 796 | } else if (NumSortedEntries != Cache->size()) { |
| 797 | std::sort(Cache->begin(), Cache->end()); |
| 798 | NumSortedEntries = Cache->size(); |
| 799 | } |
Chris Lattner | 4433a09 | 2009-01-23 06:48:41 +0000 | [diff] [blame] | 800 | |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 801 | // Since we did phi translation, the "Cache" set won't contain all of the |
| 802 | // results for the query. This is ok (we can still use it to accelerate |
| 803 | // specific block queries) but we can't do the fastpath "return all |
| 804 | // results from the set" Clear out the indicator for this. |
| 805 | CacheInfo->first = BBSkipFirstBlockPair(); |
| 806 | |
| 807 | // If *nothing* works, mark the pointer as being clobbered by the first |
| 808 | // instruction in this block. |
| 809 | // |
| 810 | // If this is the magic first block, return this as a clobber of the whole |
| 811 | // incoming value. Since we can't phi translate to one of the predecessors, |
| 812 | // we have to bail out. |
| 813 | if (SkipFirstBlock) |
| 814 | return true; |
| 815 | |
| 816 | for (NonLocalDepInfo::reverse_iterator I = Cache->rbegin(); ; ++I) { |
| 817 | assert(I != Cache->rend() && "Didn't find current block??"); |
| 818 | if (I->first != BB) |
| 819 | continue; |
| 820 | |
| 821 | assert(I->second.isNonLocal() && |
| 822 | "Should only be here with transparent block"); |
| 823 | I->second = MemDepResult::getClobber(BB->begin()); |
| 824 | ReverseNonLocalPtrDeps[BB->begin()].insert(CacheKey.getOpaqueValue()); |
| 825 | Result.push_back(*I); |
| 826 | break; |
Chris Lattner | 9a193fd | 2008-12-07 02:56:57 +0000 | [diff] [blame] | 827 | } |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 828 | } |
Chris Lattner | 95900f2 | 2009-01-23 07:12:16 +0000 | [diff] [blame^] | 829 | |
Chris Lattner | 9863c3f | 2008-12-09 07:47:11 +0000 | [diff] [blame] | 830 | // Okay, we're done now. If we added new values to the cache, re-sort it. |
Chris Lattner | ba4dacc | 2008-12-09 07:05:45 +0000 | [diff] [blame] | 831 | switch (Cache->size()-NumSortedEntries) { |
| 832 | case 0: |
Chris Lattner | 1aeadac | 2008-12-09 06:58:04 +0000 | [diff] [blame] | 833 | // done, no new entries. |
Chris Lattner | ba4dacc | 2008-12-09 07:05:45 +0000 | [diff] [blame] | 834 | break; |
| 835 | case 2: { |
| 836 | // Two new entries, insert the last one into place. |
| 837 | NonLocalDepEntry Val = Cache->back(); |
| 838 | Cache->pop_back(); |
| 839 | NonLocalDepInfo::iterator Entry = |
| 840 | std::upper_bound(Cache->begin(), Cache->end()-1, Val); |
| 841 | Cache->insert(Entry, Val); |
| 842 | // FALL THROUGH. |
| 843 | } |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 844 | case 1: |
Chris Lattner | 1aeadac | 2008-12-09 06:58:04 +0000 | [diff] [blame] | 845 | // One new entry, Just insert the new value at the appropriate position. |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 846 | if (Cache->size() != 1) { |
| 847 | NonLocalDepEntry Val = Cache->back(); |
| 848 | Cache->pop_back(); |
| 849 | NonLocalDepInfo::iterator Entry = |
| 850 | std::upper_bound(Cache->begin(), Cache->end(), Val); |
| 851 | Cache->insert(Entry, Val); |
| 852 | } |
Chris Lattner | ba4dacc | 2008-12-09 07:05:45 +0000 | [diff] [blame] | 853 | break; |
Chris Lattner | ba4dacc | 2008-12-09 07:05:45 +0000 | [diff] [blame] | 854 | default: |
Chris Lattner | 1aeadac | 2008-12-09 06:58:04 +0000 | [diff] [blame] | 855 | // Added many values, do a full scale sort. |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 856 | std::sort(Cache->begin(), Cache->end()); |
Chris Lattner | 1aeadac | 2008-12-09 06:58:04 +0000 | [diff] [blame] | 857 | } |
Chris Lattner | 12a7db3 | 2009-01-22 07:04:01 +0000 | [diff] [blame] | 858 | DEBUG(AssertSorted(*Cache)); |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 859 | return false; |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 860 | } |
| 861 | |
| 862 | /// RemoveCachedNonLocalPointerDependencies - If P exists in |
| 863 | /// CachedNonLocalPointerInfo, remove it. |
| 864 | void MemoryDependenceAnalysis:: |
| 865 | RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair P) { |
| 866 | CachedNonLocalPointerInfo::iterator It = |
| 867 | NonLocalPointerDeps.find(P); |
| 868 | if (It == NonLocalPointerDeps.end()) return; |
| 869 | |
| 870 | // Remove all of the entries in the BB->val map. This involves removing |
| 871 | // instructions from the reverse map. |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 872 | NonLocalDepInfo &PInfo = It->second.second; |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 873 | |
| 874 | for (unsigned i = 0, e = PInfo.size(); i != e; ++i) { |
| 875 | Instruction *Target = PInfo[i].second.getInst(); |
| 876 | if (Target == 0) continue; // Ignore non-local dep results. |
Chris Lattner | 5a45bf1 | 2008-12-09 22:45:32 +0000 | [diff] [blame] | 877 | assert(Target->getParent() == PInfo[i].first); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 878 | |
| 879 | // Eliminating the dirty entry from 'Cache', so update the reverse info. |
Chris Lattner | d44745d | 2008-12-07 18:39:13 +0000 | [diff] [blame] | 880 | RemoveFromReverseMap(ReverseNonLocalPtrDeps, Target, P.getOpaqueValue()); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 881 | } |
| 882 | |
| 883 | // Remove P from NonLocalPointerDeps (which deletes NonLocalDepInfo). |
| 884 | NonLocalPointerDeps.erase(It); |
Chris Lattner | 7ebcf03 | 2008-12-07 02:15:47 +0000 | [diff] [blame] | 885 | } |
| 886 | |
| 887 | |
Chris Lattner | bc99be1 | 2008-12-09 22:06:23 +0000 | [diff] [blame] | 888 | /// invalidateCachedPointerInfo - This method is used to invalidate cached |
| 889 | /// information about the specified pointer, because it may be too |
| 890 | /// conservative in memdep. This is an optional call that can be used when |
| 891 | /// the client detects an equivalence between the pointer and some other |
| 892 | /// value and replaces the other value with ptr. This can make Ptr available |
| 893 | /// in more places that cached info does not necessarily keep. |
| 894 | void MemoryDependenceAnalysis::invalidateCachedPointerInfo(Value *Ptr) { |
| 895 | // If Ptr isn't really a pointer, just ignore it. |
| 896 | if (!isa<PointerType>(Ptr->getType())) return; |
| 897 | // Flush store info for the pointer. |
| 898 | RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(Ptr, false)); |
| 899 | // Flush load info for the pointer. |
| 900 | RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(Ptr, true)); |
| 901 | } |
| 902 | |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 903 | /// removeInstruction - Remove an instruction from the dependence analysis, |
| 904 | /// updating the dependence of instructions that previously depended on it. |
Owen Anderson | 642a9e3 | 2007-08-08 22:26:03 +0000 | [diff] [blame] | 905 | /// This method attempts to keep the cache coherent using the reverse map. |
Chris Lattner | 5f589dc | 2008-11-28 22:04:47 +0000 | [diff] [blame] | 906 | void MemoryDependenceAnalysis::removeInstruction(Instruction *RemInst) { |
Chris Lattner | 5f589dc | 2008-11-28 22:04:47 +0000 | [diff] [blame] | 907 | // Walk through the Non-local dependencies, removing this one as the value |
| 908 | // for any cached queries. |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 909 | NonLocalDepMapType::iterator NLDI = NonLocalDeps.find(RemInst); |
| 910 | if (NLDI != NonLocalDeps.end()) { |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 911 | NonLocalDepInfo &BlockMap = NLDI->second.first; |
Chris Lattner | 25f4b2b | 2008-11-30 02:30:50 +0000 | [diff] [blame] | 912 | for (NonLocalDepInfo::iterator DI = BlockMap.begin(), DE = BlockMap.end(); |
| 913 | DI != DE; ++DI) |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 914 | if (Instruction *Inst = DI->second.getInst()) |
Chris Lattner | d44745d | 2008-12-07 18:39:13 +0000 | [diff] [blame] | 915 | RemoveFromReverseMap(ReverseNonLocalDeps, Inst, RemInst); |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 916 | NonLocalDeps.erase(NLDI); |
| 917 | } |
Owen Anderson | 5fc4aba | 2007-12-08 01:37:09 +0000 | [diff] [blame] | 918 | |
Chris Lattner | 5f589dc | 2008-11-28 22:04:47 +0000 | [diff] [blame] | 919 | // If we have a cached local dependence query for this instruction, remove it. |
Chris Lattner | baad888 | 2008-11-28 22:28:27 +0000 | [diff] [blame] | 920 | // |
Chris Lattner | 39f372e | 2008-11-29 01:43:36 +0000 | [diff] [blame] | 921 | LocalDepMapType::iterator LocalDepEntry = LocalDeps.find(RemInst); |
| 922 | if (LocalDepEntry != LocalDeps.end()) { |
Chris Lattner | 125ce36 | 2008-11-30 01:09:30 +0000 | [diff] [blame] | 923 | // Remove us from DepInst's reverse set now that the local dep info is gone. |
Chris Lattner | d44745d | 2008-12-07 18:39:13 +0000 | [diff] [blame] | 924 | if (Instruction *Inst = LocalDepEntry->second.getInst()) |
| 925 | RemoveFromReverseMap(ReverseLocalDeps, Inst, RemInst); |
Chris Lattner | 125ce36 | 2008-11-30 01:09:30 +0000 | [diff] [blame] | 926 | |
Chris Lattner | baad888 | 2008-11-28 22:28:27 +0000 | [diff] [blame] | 927 | // Remove this local dependency info. |
Chris Lattner | 39f372e | 2008-11-29 01:43:36 +0000 | [diff] [blame] | 928 | LocalDeps.erase(LocalDepEntry); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 929 | } |
| 930 | |
| 931 | // If we have any cached pointer dependencies on this instruction, remove |
| 932 | // them. If the instruction has non-pointer type, then it can't be a pointer |
| 933 | // base. |
| 934 | |
| 935 | // Remove it from both the load info and the store info. The instruction |
| 936 | // can't be in either of these maps if it is non-pointer. |
| 937 | if (isa<PointerType>(RemInst->getType())) { |
| 938 | RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(RemInst, false)); |
| 939 | RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair(RemInst, true)); |
| 940 | } |
Chris Lattner | baad888 | 2008-11-28 22:28:27 +0000 | [diff] [blame] | 941 | |
Chris Lattner | d3d12ec | 2008-11-28 22:51:08 +0000 | [diff] [blame] | 942 | // Loop over all of the things that depend on the instruction we're removing. |
| 943 | // |
Chris Lattner | 4f8c18c | 2008-11-29 23:30:39 +0000 | [diff] [blame] | 944 | SmallVector<std::pair<Instruction*, Instruction*>, 8> ReverseDepsToAdd; |
Chris Lattner | 0655f73 | 2008-12-07 18:42:51 +0000 | [diff] [blame] | 945 | |
| 946 | // If we find RemInst as a clobber or Def in any of the maps for other values, |
| 947 | // we need to replace its entry with a dirty version of the instruction after |
| 948 | // it. If RemInst is a terminator, we use a null dirty value. |
| 949 | // |
| 950 | // Using a dirty version of the instruction after RemInst saves having to scan |
| 951 | // the entire block to get to this point. |
| 952 | MemDepResult NewDirtyVal; |
| 953 | if (!RemInst->isTerminator()) |
| 954 | NewDirtyVal = MemDepResult::getDirty(++BasicBlock::iterator(RemInst)); |
Chris Lattner | 4f8c18c | 2008-11-29 23:30:39 +0000 | [diff] [blame] | 955 | |
Chris Lattner | 8c46527 | 2008-11-29 09:20:15 +0000 | [diff] [blame] | 956 | ReverseDepMapType::iterator ReverseDepIt = ReverseLocalDeps.find(RemInst); |
| 957 | if (ReverseDepIt != ReverseLocalDeps.end()) { |
Chris Lattner | d3d12ec | 2008-11-28 22:51:08 +0000 | [diff] [blame] | 958 | SmallPtrSet<Instruction*, 4> &ReverseDeps = ReverseDepIt->second; |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 959 | // RemInst can't be the terminator if it has local stuff depending on it. |
Chris Lattner | 125ce36 | 2008-11-30 01:09:30 +0000 | [diff] [blame] | 960 | assert(!ReverseDeps.empty() && !isa<TerminatorInst>(RemInst) && |
| 961 | "Nothing can locally depend on a terminator"); |
| 962 | |
Chris Lattner | d3d12ec | 2008-11-28 22:51:08 +0000 | [diff] [blame] | 963 | for (SmallPtrSet<Instruction*, 4>::iterator I = ReverseDeps.begin(), |
| 964 | E = ReverseDeps.end(); I != E; ++I) { |
| 965 | Instruction *InstDependingOnRemInst = *I; |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 966 | assert(InstDependingOnRemInst != RemInst && |
| 967 | "Already removed our local dep info"); |
Chris Lattner | 125ce36 | 2008-11-30 01:09:30 +0000 | [diff] [blame] | 968 | |
Chris Lattner | 0655f73 | 2008-12-07 18:42:51 +0000 | [diff] [blame] | 969 | LocalDeps[InstDependingOnRemInst] = NewDirtyVal; |
Chris Lattner | d3d12ec | 2008-11-28 22:51:08 +0000 | [diff] [blame] | 970 | |
Chris Lattner | 125ce36 | 2008-11-30 01:09:30 +0000 | [diff] [blame] | 971 | // Make sure to remember that new things depend on NewDepInst. |
Chris Lattner | 0655f73 | 2008-12-07 18:42:51 +0000 | [diff] [blame] | 972 | assert(NewDirtyVal.getInst() && "There is no way something else can have " |
| 973 | "a local dep on this if it is a terminator!"); |
| 974 | ReverseDepsToAdd.push_back(std::make_pair(NewDirtyVal.getInst(), |
Chris Lattner | 125ce36 | 2008-11-30 01:09:30 +0000 | [diff] [blame] | 975 | InstDependingOnRemInst)); |
Chris Lattner | d3d12ec | 2008-11-28 22:51:08 +0000 | [diff] [blame] | 976 | } |
Chris Lattner | 4f8c18c | 2008-11-29 23:30:39 +0000 | [diff] [blame] | 977 | |
| 978 | ReverseLocalDeps.erase(ReverseDepIt); |
| 979 | |
| 980 | // Add new reverse deps after scanning the set, to avoid invalidating the |
| 981 | // 'ReverseDeps' reference. |
| 982 | while (!ReverseDepsToAdd.empty()) { |
| 983 | ReverseLocalDeps[ReverseDepsToAdd.back().first] |
| 984 | .insert(ReverseDepsToAdd.back().second); |
| 985 | ReverseDepsToAdd.pop_back(); |
| 986 | } |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 987 | } |
Owen Anderson | 4d13de4 | 2007-08-16 21:27:05 +0000 | [diff] [blame] | 988 | |
Chris Lattner | 8c46527 | 2008-11-29 09:20:15 +0000 | [diff] [blame] | 989 | ReverseDepIt = ReverseNonLocalDeps.find(RemInst); |
| 990 | if (ReverseDepIt != ReverseNonLocalDeps.end()) { |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 991 | SmallPtrSet<Instruction*, 4> &Set = ReverseDepIt->second; |
| 992 | for (SmallPtrSet<Instruction*, 4>::iterator I = Set.begin(), E = Set.end(); |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 993 | I != E; ++I) { |
| 994 | assert(*I != RemInst && "Already removed NonLocalDep info for RemInst"); |
| 995 | |
Chris Lattner | 4a69bad | 2008-11-30 02:52:26 +0000 | [diff] [blame] | 996 | PerInstNLInfo &INLD = NonLocalDeps[*I]; |
Chris Lattner | 4a69bad | 2008-11-30 02:52:26 +0000 | [diff] [blame] | 997 | // The information is now dirty! |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 998 | INLD.second = true; |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 999 | |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 1000 | for (NonLocalDepInfo::iterator DI = INLD.first.begin(), |
| 1001 | DE = INLD.first.end(); DI != DE; ++DI) { |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 1002 | if (DI->second.getInst() != RemInst) continue; |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 1003 | |
| 1004 | // Convert to a dirty entry for the subsequent instruction. |
Chris Lattner | 0655f73 | 2008-12-07 18:42:51 +0000 | [diff] [blame] | 1005 | DI->second = NewDirtyVal; |
| 1006 | |
| 1007 | if (Instruction *NextI = NewDirtyVal.getInst()) |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 1008 | ReverseDepsToAdd.push_back(std::make_pair(NextI, *I)); |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 1009 | } |
| 1010 | } |
Chris Lattner | 4f8c18c | 2008-11-29 23:30:39 +0000 | [diff] [blame] | 1011 | |
| 1012 | ReverseNonLocalDeps.erase(ReverseDepIt); |
| 1013 | |
Chris Lattner | 0ec48dd | 2008-11-29 22:02:15 +0000 | [diff] [blame] | 1014 | // Add new reverse deps after scanning the set, to avoid invalidating 'Set' |
| 1015 | while (!ReverseDepsToAdd.empty()) { |
| 1016 | ReverseNonLocalDeps[ReverseDepsToAdd.back().first] |
| 1017 | .insert(ReverseDepsToAdd.back().second); |
| 1018 | ReverseDepsToAdd.pop_back(); |
| 1019 | } |
Owen Anderson | 4d13de4 | 2007-08-16 21:27:05 +0000 | [diff] [blame] | 1020 | } |
Owen Anderson | 5fc4aba | 2007-12-08 01:37:09 +0000 | [diff] [blame] | 1021 | |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 1022 | // If the instruction is in ReverseNonLocalPtrDeps then it appears as a |
| 1023 | // value in the NonLocalPointerDeps info. |
| 1024 | ReverseNonLocalPtrDepTy::iterator ReversePtrDepIt = |
| 1025 | ReverseNonLocalPtrDeps.find(RemInst); |
| 1026 | if (ReversePtrDepIt != ReverseNonLocalPtrDeps.end()) { |
| 1027 | SmallPtrSet<void*, 4> &Set = ReversePtrDepIt->second; |
| 1028 | SmallVector<std::pair<Instruction*, ValueIsLoadPair>,8> ReversePtrDepsToAdd; |
| 1029 | |
| 1030 | for (SmallPtrSet<void*, 4>::iterator I = Set.begin(), E = Set.end(); |
| 1031 | I != E; ++I) { |
| 1032 | ValueIsLoadPair P; |
| 1033 | P.setFromOpaqueValue(*I); |
| 1034 | assert(P.getPointer() != RemInst && |
| 1035 | "Already removed NonLocalPointerDeps info for RemInst"); |
| 1036 | |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 1037 | NonLocalDepInfo &NLPDI = NonLocalPointerDeps[P].second; |
| 1038 | |
| 1039 | // The cache is not valid for any specific block anymore. |
Chris Lattner | 9e59c64 | 2008-12-15 03:35:32 +0000 | [diff] [blame] | 1040 | NonLocalPointerDeps[P].first = BBSkipFirstBlockPair(); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 1041 | |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 1042 | // Update any entries for RemInst to use the instruction after it. |
| 1043 | for (NonLocalDepInfo::iterator DI = NLPDI.begin(), DE = NLPDI.end(); |
| 1044 | DI != DE; ++DI) { |
| 1045 | if (DI->second.getInst() != RemInst) continue; |
| 1046 | |
| 1047 | // Convert to a dirty entry for the subsequent instruction. |
| 1048 | DI->second = NewDirtyVal; |
| 1049 | |
| 1050 | if (Instruction *NewDirtyInst = NewDirtyVal.getInst()) |
| 1051 | ReversePtrDepsToAdd.push_back(std::make_pair(NewDirtyInst, P)); |
| 1052 | } |
Chris Lattner | 95900f2 | 2009-01-23 07:12:16 +0000 | [diff] [blame^] | 1053 | |
| 1054 | // Re-sort the NonLocalDepInfo. Changing the dirty entry to its |
| 1055 | // subsequent value may invalidate the sortedness. |
| 1056 | std::sort(NLPDI.begin(), NLPDI.end()); |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 1057 | } |
| 1058 | |
| 1059 | ReverseNonLocalPtrDeps.erase(ReversePtrDepIt); |
| 1060 | |
| 1061 | while (!ReversePtrDepsToAdd.empty()) { |
| 1062 | ReverseNonLocalPtrDeps[ReversePtrDepsToAdd.back().first] |
| 1063 | .insert(ReversePtrDepsToAdd.back().second.getOpaqueValue()); |
| 1064 | ReversePtrDepsToAdd.pop_back(); |
| 1065 | } |
| 1066 | } |
| 1067 | |
| 1068 | |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 1069 | assert(!NonLocalDeps.count(RemInst) && "RemInst got reinserted?"); |
Chris Lattner | d777d40 | 2008-11-30 19:24:31 +0000 | [diff] [blame] | 1070 | AA->deleteValue(RemInst); |
Chris Lattner | 5f589dc | 2008-11-28 22:04:47 +0000 | [diff] [blame] | 1071 | DEBUG(verifyRemoved(RemInst)); |
Owen Anderson | 78e02f7 | 2007-07-06 23:14:35 +0000 | [diff] [blame] | 1072 | } |
Chris Lattner | 729b237 | 2008-11-29 21:25:10 +0000 | [diff] [blame] | 1073 | /// verifyRemoved - Verify that the specified instruction does not occur |
| 1074 | /// in our internal data structures. |
| 1075 | void MemoryDependenceAnalysis::verifyRemoved(Instruction *D) const { |
| 1076 | for (LocalDepMapType::const_iterator I = LocalDeps.begin(), |
| 1077 | E = LocalDeps.end(); I != E; ++I) { |
| 1078 | assert(I->first != D && "Inst occurs in data structures"); |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 1079 | assert(I->second.getInst() != D && |
Chris Lattner | 729b237 | 2008-11-29 21:25:10 +0000 | [diff] [blame] | 1080 | "Inst occurs in data structures"); |
| 1081 | } |
| 1082 | |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 1083 | for (CachedNonLocalPointerInfo::const_iterator I =NonLocalPointerDeps.begin(), |
| 1084 | E = NonLocalPointerDeps.end(); I != E; ++I) { |
| 1085 | assert(I->first.getPointer() != D && "Inst occurs in NLPD map key"); |
Chris Lattner | 11dcd8d | 2008-12-08 07:31:50 +0000 | [diff] [blame] | 1086 | const NonLocalDepInfo &Val = I->second.second; |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 1087 | for (NonLocalDepInfo::const_iterator II = Val.begin(), E = Val.end(); |
| 1088 | II != E; ++II) |
| 1089 | assert(II->second.getInst() != D && "Inst occurs as NLPD value"); |
| 1090 | } |
| 1091 | |
Chris Lattner | 729b237 | 2008-11-29 21:25:10 +0000 | [diff] [blame] | 1092 | for (NonLocalDepMapType::const_iterator I = NonLocalDeps.begin(), |
| 1093 | E = NonLocalDeps.end(); I != E; ++I) { |
| 1094 | assert(I->first != D && "Inst occurs in data structures"); |
Chris Lattner | 4a69bad | 2008-11-30 02:52:26 +0000 | [diff] [blame] | 1095 | const PerInstNLInfo &INLD = I->second; |
Chris Lattner | bf145d6 | 2008-12-01 01:15:42 +0000 | [diff] [blame] | 1096 | for (NonLocalDepInfo::const_iterator II = INLD.first.begin(), |
| 1097 | EE = INLD.first.end(); II != EE; ++II) |
Chris Lattner | fd3dcbe | 2008-11-30 23:17:19 +0000 | [diff] [blame] | 1098 | assert(II->second.getInst() != D && "Inst occurs in data structures"); |
Chris Lattner | 729b237 | 2008-11-29 21:25:10 +0000 | [diff] [blame] | 1099 | } |
| 1100 | |
| 1101 | for (ReverseDepMapType::const_iterator I = ReverseLocalDeps.begin(), |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 1102 | E = ReverseLocalDeps.end(); I != E; ++I) { |
| 1103 | assert(I->first != D && "Inst occurs in data structures"); |
Chris Lattner | 729b237 | 2008-11-29 21:25:10 +0000 | [diff] [blame] | 1104 | for (SmallPtrSet<Instruction*, 4>::const_iterator II = I->second.begin(), |
| 1105 | EE = I->second.end(); II != EE; ++II) |
| 1106 | assert(*II != D && "Inst occurs in data structures"); |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 1107 | } |
Chris Lattner | 729b237 | 2008-11-29 21:25:10 +0000 | [diff] [blame] | 1108 | |
| 1109 | for (ReverseDepMapType::const_iterator I = ReverseNonLocalDeps.begin(), |
| 1110 | E = ReverseNonLocalDeps.end(); |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 1111 | I != E; ++I) { |
| 1112 | assert(I->first != D && "Inst occurs in data structures"); |
Chris Lattner | 729b237 | 2008-11-29 21:25:10 +0000 | [diff] [blame] | 1113 | for (SmallPtrSet<Instruction*, 4>::const_iterator II = I->second.begin(), |
| 1114 | EE = I->second.end(); II != EE; ++II) |
| 1115 | assert(*II != D && "Inst occurs in data structures"); |
Chris Lattner | f68f310 | 2008-11-30 02:28:25 +0000 | [diff] [blame] | 1116 | } |
Chris Lattner | 6290f5c | 2008-12-07 08:50:20 +0000 | [diff] [blame] | 1117 | |
| 1118 | for (ReverseNonLocalPtrDepTy::const_iterator |
| 1119 | I = ReverseNonLocalPtrDeps.begin(), |
| 1120 | E = ReverseNonLocalPtrDeps.end(); I != E; ++I) { |
| 1121 | assert(I->first != D && "Inst occurs in rev NLPD map"); |
| 1122 | |
| 1123 | for (SmallPtrSet<void*, 4>::const_iterator II = I->second.begin(), |
| 1124 | E = I->second.end(); II != E; ++II) |
| 1125 | assert(*II != ValueIsLoadPair(D, false).getOpaqueValue() && |
| 1126 | *II != ValueIsLoadPair(D, true).getOpaqueValue() && |
| 1127 | "Inst occurs in ReverseNonLocalPtrDeps map"); |
| 1128 | } |
| 1129 | |
Chris Lattner | 729b237 | 2008-11-29 21:25:10 +0000 | [diff] [blame] | 1130 | } |