14df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner//===- llvm/Analysis/AliasAnalysis.h - Alias Analysis Interface -*- 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//===----------------------------------------------------------------------===// 94df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner// 104df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner// This file defines the generic AliasAnalysis interface, which is used as the 114df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner// common interface used by all clients of alias analysis information, and 121c56b730a6313886076d7b293a126ae5576f5288Chris Lattner// implemented by all alias analysis implementations. Mod/Ref information is 131c56b730a6313886076d7b293a126ae5576f5288Chris Lattner// also captured by this interface. 144df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner// 154df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner// Implementations of this interface must implement the various virtual methods, 164df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner// which automatically provides functionality for the entire suite of client 174df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner// APIs. 184df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner// 198e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// This API identifies memory regions with the Location class. The pointer 208e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// component specifies the base memory address of the region. The Size specifies 218e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// the maximum size (in address units) of the memory region, or UnknownSize if 228e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// the size is not known. The TBAA tag identifies the "type" of the memory 238e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// reference; see the TypeBasedAliasAnalysis class for details. 248e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// 258e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// Some non-obvious details include: 268e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// - Pointers that point to two completely different objects in memory never 278e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// alias, regardless of the value of the Size component. 288e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// - NoAlias doesn't imply inequal pointers. The most obvious example of this 298e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// is two pointers to constant memory. Even if they are equal, constant 308e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// memory is never stored to, so there will never be any dependencies. 318e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// In this and other situations, the pointers may be both NoAlias and 328e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// MustAlias at the same time. The current API can only return one result, 338e78cc4e130a8773cc8a2be2a94c4a97317ac383Dan Gohman// though this is rarely a problem in practice. 341c56b730a6313886076d7b293a126ae5576f5288Chris Lattner// 354df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner//===----------------------------------------------------------------------===// 364df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 37674be02d525d4e24bc6943ed9274958c580bcfbcJakub Staszak#ifndef LLVM_ANALYSIS_ALIASANALYSIS_H 38674be02d525d4e24bc6943ed9274958c580bcfbcJakub Staszak#define LLVM_ANALYSIS_ALIASANALYSIS_H 394df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 401fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman#include "llvm/ADT/DenseMap.h" 41255f89faee13dc491cb64fbeae3c763e7e2ea4e6Chandler Carruth#include "llvm/Support/CallSite.h" 42d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 43d0fde30ce850b78371fd1386338350591f9ff494Brian Gaekenamespace llvm { 44d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 451c56b730a6313886076d7b293a126ae5576f5288Chris Lattnerclass LoadInst; 461c56b730a6313886076d7b293a126ae5576f5288Chris Lattnerclass StoreInst; 4714f1703ae33e13dbcadd701603fd4d7a6f7010b9Andrew Lenharthclass VAArgInst; 483574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmowclass DataLayout; 498e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramerclass TargetLibraryInfo; 506df60a9effe4d20a48cfd9d105c0ab3c5dc3e690Reid Spencerclass Pass; 516df60a9effe4d20a48cfd9d105c0ab3c5dc3e690Reid Spencerclass AnalysisUsage; 52e90c5cb747631b315350e7ee7424048c7778bdf9Chris Lattnerclass MemTransferInst; 539dc9e81aa7412b329bbaf51a589a81475214802bChris Lattnerclass MemIntrinsic; 543a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosierclass DominatorTree; 551c56b730a6313886076d7b293a126ae5576f5288Chris Lattner 561c56b730a6313886076d7b293a126ae5576f5288Chris Lattnerclass AliasAnalysis { 571c56b730a6313886076d7b293a126ae5576f5288Chris Lattnerprotected: 583574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *TD; 598e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer const TargetLibraryInfo *TLI; 60cb74993bdc37681ddbb80fa361575107afae1350Dan Gohman 61cb74993bdc37681ddbb80fa361575107afae1350Dan Gohmanprivate: 62ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner AliasAnalysis *AA; // Previous Alias Analysis to chain to. 63ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner 64cb74993bdc37681ddbb80fa361575107afae1350Dan Gohmanprotected: 651c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// InitializeAliasAnalysis - Subclasses must call this method to initialize 661c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// the AliasAnalysis interface before any other methods are called. This is 671c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// typically called by the run* methods of these subclasses. This may be 681c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// called multiple times. 691c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// 701c56b730a6313886076d7b293a126ae5576f5288Chris Lattner void InitializeAliasAnalysis(Pass *P); 719769ab22265b313171d201b5928688524a01bd87Misha Brukman 7264d237cfae6bcb11157d525c79b5a5335e30370bDan Gohman /// getAnalysisUsage - All alias analysis implementations should invoke this 73fc2a3ed0c9e32cf7edaf5030fa0972b916cc5f0bDan Gohman /// directly (using AliasAnalysis::getAnalysisUsage(AU)). 741c56b730a6313886076d7b293a126ae5576f5288Chris Lattner virtual void getAnalysisUsage(AnalysisUsage &AU) const; 751c56b730a6313886076d7b293a126ae5576f5288Chris Lattner 761c56b730a6313886076d7b293a126ae5576f5288Chris Lattnerpublic: 771997473cf72957d0e70322e2fe6fe2ab141c58a6Devang Patel static char ID; // Class identification, replacement for typeinfo 788e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer AliasAnalysis() : TD(0), TLI(0), AA(0) {} 791c56b730a6313886076d7b293a126ae5576f5288Chris Lattner virtual ~AliasAnalysis(); // We want to be subclassed 801c56b730a6313886076d7b293a126ae5576f5288Chris Lattner 81ef1cfac9e50def9097cd3e3ab3c5cad7f4c758ccDan Gohman /// UnknownSize - This is a special value which can be used with the 82ef1cfac9e50def9097cd3e3ab3c5cad7f4c758ccDan Gohman /// size arguments in alias queries to indicate that the caller does not 83ef1cfac9e50def9097cd3e3ab3c5cad7f4c758ccDan Gohman /// know the sizes of the potential memory references. 843da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman static uint64_t const UnknownSize = ~UINT64_C(0); 85ef1cfac9e50def9097cd3e3ab3c5cad7f4c758ccDan Gohman 863574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow /// getDataLayout - Return a pointer to the current DataLayout object, or 873574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow /// null if no DataLayout object is available. 88dd298c8c6eb036baf35bf5a559c59d2afd2c7944Misha Brukman /// 893574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow const DataLayout *getDataLayout() const { return TD; } 90fc2a3ed0c9e32cf7edaf5030fa0972b916cc5f0bDan Gohman 918e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer /// getTargetLibraryInfo - Return a pointer to the current TargetLibraryInfo 928e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer /// object, or null if no TargetLibraryInfo object is available. 938e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer /// 948e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer const TargetLibraryInfo *getTargetLibraryInfo() const { return TLI; } 958e0d1c03ca7fd86e6879b4e37d0d7f0e982feef6Benjamin Kramer 963574eca1b02600bac4e625297f4ecf745f4c4f32Micah Villmow /// getTypeStoreSize - Return the DataLayout store size for the given type, 97fc2a3ed0c9e32cf7edaf5030fa0972b916cc5f0bDan Gohman /// if known, or a conservative value otherwise. 98fc2a3ed0c9e32cf7edaf5030fa0972b916cc5f0bDan Gohman /// 99db125cfaf57cc83e7dd7453de2d509bc8efd0e5eChris Lattner uint64_t getTypeStoreSize(Type *Ty); 1004df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 1011c56b730a6313886076d7b293a126ae5576f5288Chris Lattner //===--------------------------------------------------------------------===// 1021c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// Alias Queries... 1031c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// 1044df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 105b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// Location - A description of a memory location. 106b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman struct Location { 107b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// Ptr - The address of the start of the location. 108b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman const Value *Ptr; 109a6d60ddbbb0c33690f7e89cad2b5e60cee84b89eDan Gohman /// Size - The maximum size of the location, in address-units, or 110a6d60ddbbb0c33690f7e89cad2b5e60cee84b89eDan Gohman /// UnknownSize if the size is not known. Note that an unknown size does 111a6d60ddbbb0c33690f7e89cad2b5e60cee84b89eDan Gohman /// not mean the pointer aliases the entire virtual address space, because 112a6d60ddbbb0c33690f7e89cad2b5e60cee84b89eDan Gohman /// there are restrictions on stepping out of one object and into another. 1136c25c920e66aa2d8f6b48454bc9770087ff7939aDan Gohman /// See http://llvm.org/docs/LangRef.html#pointeraliasing 1143da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman uint64_t Size; 115b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// TBAATag - The metadata node which describes the TBAA type of 1166c25c920e66aa2d8f6b48454bc9770087ff7939aDan Gohman /// the location, or null if there is no known unique tag. 117b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman const MDNode *TBAATag; 118b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 119c413330c99a573ef3ffe80a46400b1d3eca2398dChris Lattner explicit Location(const Value *P = 0, uint64_t S = UnknownSize, 120b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman const MDNode *N = 0) 121b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman : Ptr(P), Size(S), TBAATag(N) {} 1229f27074f42f03af640977006dc7c05005fb77991Dan Gohman 1239f27074f42f03af640977006dc7c05005fb77991Dan Gohman Location getWithNewPtr(const Value *NewPtr) const { 1249f27074f42f03af640977006dc7c05005fb77991Dan Gohman Location Copy(*this); 1259f27074f42f03af640977006dc7c05005fb77991Dan Gohman Copy.Ptr = NewPtr; 1269f27074f42f03af640977006dc7c05005fb77991Dan Gohman return Copy; 1279f27074f42f03af640977006dc7c05005fb77991Dan Gohman } 1289f27074f42f03af640977006dc7c05005fb77991Dan Gohman 129075fb5d68fcb55d26e44c48f07dfdbbfa21ccb2aDan Gohman Location getWithNewSize(uint64_t NewSize) const { 130075fb5d68fcb55d26e44c48f07dfdbbfa21ccb2aDan Gohman Location Copy(*this); 131075fb5d68fcb55d26e44c48f07dfdbbfa21ccb2aDan Gohman Copy.Size = NewSize; 132075fb5d68fcb55d26e44c48f07dfdbbfa21ccb2aDan Gohman return Copy; 133075fb5d68fcb55d26e44c48f07dfdbbfa21ccb2aDan Gohman } 134075fb5d68fcb55d26e44c48f07dfdbbfa21ccb2aDan Gohman 1359f27074f42f03af640977006dc7c05005fb77991Dan Gohman Location getWithoutTBAATag() const { 1369f27074f42f03af640977006dc7c05005fb77991Dan Gohman Location Copy(*this); 1379f27074f42f03af640977006dc7c05005fb77991Dan Gohman Copy.TBAATag = 0; 1389f27074f42f03af640977006dc7c05005fb77991Dan Gohman return Copy; 1399f27074f42f03af640977006dc7c05005fb77991Dan Gohman } 140b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman }; 141b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 1426d8eb156e6be727570b300bac7712f745a318c7dDan Gohman /// getLocation - Fill in Loc with information about the memory reference by 1436d8eb156e6be727570b300bac7712f745a318c7dDan Gohman /// the given instruction. 1446d8eb156e6be727570b300bac7712f745a318c7dDan Gohman Location getLocation(const LoadInst *LI); 1456d8eb156e6be727570b300bac7712f745a318c7dDan Gohman Location getLocation(const StoreInst *SI); 1466d8eb156e6be727570b300bac7712f745a318c7dDan Gohman Location getLocation(const VAArgInst *VI); 14746cb5afdcd031c371c78201fb34291d9d48b2ee4Eli Friedman Location getLocation(const AtomicCmpXchgInst *CXI); 14846cb5afdcd031c371c78201fb34291d9d48b2ee4Eli Friedman Location getLocation(const AtomicRMWInst *RMWI); 14916f7993e0df4bd0727f8535bd47a2776bec10545Chris Lattner static Location getLocationForSource(const MemTransferInst *MTI); 1509dc9e81aa7412b329bbaf51a589a81475214802bChris Lattner static Location getLocationForDest(const MemIntrinsic *MI); 1516d8eb156e6be727570b300bac7712f745a318c7dDan Gohman 152f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// Alias analysis result - Either we know for sure that it does not alias, we 153f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// know for sure it must alias, or we don't know anything: The two pointers 154f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// _might_ alias. This enum is designed so you can do things like: 155f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// if (AA.alias(P1, P2)) { ... } 156f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// to check to see if two pointers might alias. 157f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// 158e53e3772f3c8b4cba69b7d77c8b2148a080fe9aeDan Gohman /// See docs/AliasAnalysis.html for more information on the specific meanings 159e53e3772f3c8b4cba69b7d77c8b2148a080fe9aeDan Gohman /// of these values. 160e53e3772f3c8b4cba69b7d77c8b2148a080fe9aeDan Gohman /// 16117e8078ae14ed71f657d59c77efa3bedf171161aDan Gohman enum AliasResult { 16217e8078ae14ed71f657d59c77efa3bedf171161aDan Gohman NoAlias = 0, ///< No dependencies. 1634a34cbd2b9ba9efcdab4c4e656df2d7bd22e2604Dan Gohman MayAlias, ///< Anything goes. 1644a34cbd2b9ba9efcdab4c4e656df2d7bd22e2604Dan Gohman PartialAlias, ///< Pointers differ, but pointees overlap. 1654a34cbd2b9ba9efcdab4c4e656df2d7bd22e2604Dan Gohman MustAlias ///< Pointers are equal. 16617e8078ae14ed71f657d59c77efa3bedf171161aDan Gohman }; 1674df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 168f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// alias - The main low level interface to the alias analysis implementation. 1696c25c920e66aa2d8f6b48454bc9770087ff7939aDan Gohman /// Returns an AliasResult indicating whether the two pointers are aliased to 1706c25c920e66aa2d8f6b48454bc9770087ff7939aDan Gohman /// each other. This is the interface that must be implemented by specific 1716c25c920e66aa2d8f6b48454bc9770087ff7939aDan Gohman /// alias analysis implementations. 172b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman virtual AliasResult alias(const Location &LocA, const Location &LocB); 1734df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 174b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// alias - A convenience wrapper. 1753da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman AliasResult alias(const Value *V1, uint64_t V1Size, 1763da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman const Value *V2, uint64_t V2Size) { 177b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return alias(Location(V1, V1Size), Location(V2, V2Size)); 178b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 179b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 180b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// alias - A convenience wrapper. 181847a84efd23a2c7d90429b82f6e0f19d1f913d9aDan Gohman AliasResult alias(const Value *V1, const Value *V2) { 182ef1cfac9e50def9097cd3e3ab3c5cad7f4c758ccDan Gohman return alias(V1, UnknownSize, V2, UnknownSize); 183847a84efd23a2c7d90429b82f6e0f19d1f913d9aDan Gohman } 184847a84efd23a2c7d90429b82f6e0f19d1f913d9aDan Gohman 185c46530b6a32a53edf0d6d32bcd09ea5d76940472Chris Lattner /// isNoAlias - A trivial helper function to check to see if the specified 186c46530b6a32a53edf0d6d32bcd09ea5d76940472Chris Lattner /// pointers are no-alias. 187b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman bool isNoAlias(const Location &LocA, const Location &LocB) { 188b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return alias(LocA, LocB) == NoAlias; 189b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 190b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 191b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// isNoAlias - A convenience wrapper. 1923da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman bool isNoAlias(const Value *V1, uint64_t V1Size, 1933da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman const Value *V2, uint64_t V2Size) { 194b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return isNoAlias(Location(V1, V1Size), Location(V2, V2Size)); 195c46530b6a32a53edf0d6d32bcd09ea5d76940472Chris Lattner } 19672c194a8be83d217360ebc6b1f3ad21c5ffa16a9Chris Lattner 197230768bd1316a012e88ac62689589fe5e2f10456Dan Gohman /// isNoAlias - A convenience wrapper. 198230768bd1316a012e88ac62689589fe5e2f10456Dan Gohman bool isNoAlias(const Value *V1, const Value *V2) { 199230768bd1316a012e88ac62689589fe5e2f10456Dan Gohman return isNoAlias(Location(V1), Location(V2)); 200230768bd1316a012e88ac62689589fe5e2f10456Dan Gohman } 201230768bd1316a012e88ac62689589fe5e2f10456Dan Gohman 20272c194a8be83d217360ebc6b1f3ad21c5ffa16a9Chris Lattner /// isMustAlias - A convenience wrapper. 20372c194a8be83d217360ebc6b1f3ad21c5ffa16a9Chris Lattner bool isMustAlias(const Location &LocA, const Location &LocB) { 20472c194a8be83d217360ebc6b1f3ad21c5ffa16a9Chris Lattner return alias(LocA, LocB) == MustAlias; 20572c194a8be83d217360ebc6b1f3ad21c5ffa16a9Chris Lattner } 206c46530b6a32a53edf0d6d32bcd09ea5d76940472Chris Lattner 207cc10244d7725f191bdc91cd62befff0c97257c7bChris Lattner /// isMustAlias - A convenience wrapper. 208cc10244d7725f191bdc91cd62befff0c97257c7bChris Lattner bool isMustAlias(const Value *V1, const Value *V2) { 209cc10244d7725f191bdc91cd62befff0c97257c7bChris Lattner return alias(V1, 1, V2, 1) == MustAlias; 210cc10244d7725f191bdc91cd62befff0c97257c7bChris Lattner } 211cc10244d7725f191bdc91cd62befff0c97257c7bChris Lattner 212a25e5dbcc2371352386a01e3c1b8e76dd890272bDan Gohman /// pointsToConstantMemory - If the specified memory location is 213a25e5dbcc2371352386a01e3c1b8e76dd890272bDan Gohman /// known to be constant, return true. If OrLocal is true and the 214a25e5dbcc2371352386a01e3c1b8e76dd890272bDan Gohman /// specified memory location is known to be "local" (derived from 215a25e5dbcc2371352386a01e3c1b8e76dd890272bDan Gohman /// an alloca), return true. Otherwise return false. 216a25e5dbcc2371352386a01e3c1b8e76dd890272bDan Gohman virtual bool pointsToConstantMemory(const Location &Loc, 217a25e5dbcc2371352386a01e3c1b8e76dd890272bDan Gohman bool OrLocal = false); 218b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 219b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// pointsToConstantMemory - A convenient wrapper. 220a25e5dbcc2371352386a01e3c1b8e76dd890272bDan Gohman bool pointsToConstantMemory(const Value *P, bool OrLocal = false) { 221a25e5dbcc2371352386a01e3c1b8e76dd890272bDan Gohman return pointsToConstantMemory(Location(P), OrLocal); 222b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 22362b5c167de0ca5883a7ad5eb0900eb0c15ad3707Chris Lattner 224248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner //===--------------------------------------------------------------------===// 225248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// Simple mod/ref information... 226248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// 227248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner 228248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// ModRefResult - Represent the result of a mod/ref query. Mod and Ref are 229248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// bits which may be or'd together. 230248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// 231248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner enum ModRefResult { NoModRef = 0, Ref = 1, Mod = 2, ModRef = 3 }; 2329769ab22265b313171d201b5928688524a01bd87Misha Brukman 23342c31a70735e55bf82e66a9315c97d1821c9a798Dan Gohman /// These values define additional bits used to define the 23442c31a70735e55bf82e66a9315c97d1821c9a798Dan Gohman /// ModRefBehavior values. 23542c31a70735e55bf82e66a9315c97d1821c9a798Dan Gohman enum { Nowhere = 0, ArgumentPointees = 4, Anywhere = 8 | ArgumentPointees }; 2369769ab22265b313171d201b5928688524a01bd87Misha Brukman 237248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// ModRefBehavior - Summary of how a function affects memory in the program. 238248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// Loads from constant globals are not considered memory accesses for this 239248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// interface. Also, functions may freely modify stack space local to their 240248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner /// invocation without having to report it through these interfaces. 241248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner enum ModRefBehavior { 24250a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// DoesNotAccessMemory - This function does not perform any non-local loads 24350a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// or stores to memory. 24450a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// 24550a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// This property corresponds to the GCC 'const' attribute. 24650a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// This property corresponds to the LLVM IR 'readnone' attribute. 24750a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// This property corresponds to the IntrNoMem LLVM intrinsic flag. 24842c31a70735e55bf82e66a9315c97d1821c9a798Dan Gohman DoesNotAccessMemory = Nowhere | NoModRef, 2499769ab22265b313171d201b5928688524a01bd87Misha Brukman 250e88ccb545d0e03fd4445d361100fc95f350c6663Dan Gohman /// OnlyReadsArgumentPointees - The only memory references in this function 251e88ccb545d0e03fd4445d361100fc95f350c6663Dan Gohman /// (if it has any) are non-volatile loads from objects pointed to by its 252e88ccb545d0e03fd4445d361100fc95f350c6663Dan Gohman /// pointer-typed arguments, with arbitrary offsets. 25350a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// 25450a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// This property corresponds to the IntrReadArgMem LLVM intrinsic flag. 255e88ccb545d0e03fd4445d361100fc95f350c6663Dan Gohman OnlyReadsArgumentPointees = ArgumentPointees | Ref, 256db78c4873ea8c4b3dce90d761a1ad59d5bcdd6e7Dan Gohman 257e88ccb545d0e03fd4445d361100fc95f350c6663Dan Gohman /// OnlyAccessesArgumentPointees - The only memory references in this 258e88ccb545d0e03fd4445d361100fc95f350c6663Dan Gohman /// function (if it has any) are non-volatile loads and stores from objects 259e88ccb545d0e03fd4445d361100fc95f350c6663Dan Gohman /// pointed to by its pointer-typed arguments, with arbitrary offsets. 26050a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// 26150a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// This property corresponds to the IntrReadWriteArgMem LLVM intrinsic flag. 262e88ccb545d0e03fd4445d361100fc95f350c6663Dan Gohman OnlyAccessesArgumentPointees = ArgumentPointees | ModRef, 2639769ab22265b313171d201b5928688524a01bd87Misha Brukman 26450a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// OnlyReadsMemory - This function does not perform any non-local stores or 26550a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// volatile loads, but may read from any memory location. 26650a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// 26750a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// This property corresponds to the GCC 'pure' attribute. 26850a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// This property corresponds to the LLVM IR 'readonly' attribute. 26950a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// This property corresponds to the IntrReadMem LLVM intrinsic flag. 27042c31a70735e55bf82e66a9315c97d1821c9a798Dan Gohman OnlyReadsMemory = Anywhere | Ref, 2719769ab22265b313171d201b5928688524a01bd87Misha Brukman 27250a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// UnknownModRefBehavior - This indicates that the function could not be 27350a04d067f8803d52cababdabe5c188844c5c210Dan Gohman /// classified into one of the behaviors above. 27442c31a70735e55bf82e66a9315c97d1821c9a798Dan Gohman UnknownModRefBehavior = Anywhere | ModRef 275248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner }; 2769769ab22265b313171d201b5928688524a01bd87Misha Brukman 277dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// getModRefBehavior - Return the behavior when calling the given call site. 278a41af344c2964573318a77e2b43eafd4d3804003Dan Gohman virtual ModRefBehavior getModRefBehavior(ImmutableCallSite CS); 279dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands 280dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// getModRefBehavior - Return the behavior when calling the given function. 281dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// For use when the call site is not known. 282a41af344c2964573318a77e2b43eafd4d3804003Dan Gohman virtual ModRefBehavior getModRefBehavior(const Function *F); 283dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands 284dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// doesNotAccessMemory - If the specified call is known to never read or 285dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// write memory, return true. If the call only reads from known-constant 286dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// memory, it is also legal to return true. Calls that unwind the stack 287dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// are legal for this predicate. 2883e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// 289dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// Many optimizations (such as CSE and LICM) can be performed on such calls 290dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// without worrying about aliasing properties, and many calls have this 291dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// property (e.g. calls to 'sin' and 'cos'). 2923e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// 2933e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// This property corresponds to the GCC 'const' attribute. 2943e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// 29579fca6fea87be7221843031870bbf2c9ae1fc555Dan Gohman bool doesNotAccessMemory(ImmutableCallSite CS) { 296652f7ea955bb433d6b7a4d33685dca9485fd7b8bEvan Cheng return getModRefBehavior(CS) == DoesNotAccessMemory; 297dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands } 298dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands 299dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// doesNotAccessMemory - If the specified function is known to never read or 300dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// write memory, return true. For use when the call site is not known. 301dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// 30279fca6fea87be7221843031870bbf2c9ae1fc555Dan Gohman bool doesNotAccessMemory(const Function *F) { 303dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands return getModRefBehavior(F) == DoesNotAccessMemory; 304248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner } 3053e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner 306dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// onlyReadsMemory - If the specified call is known to only read from 307dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// non-volatile memory (or not access memory at all), return true. Calls 308dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// that unwind the stack are legal for this predicate. 3093e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// 3103e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// This property allows many common optimizations to be performed in the 3113e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// absence of interfering store instructions, such as CSE of strlen calls. 3123e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// 3133e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// This property corresponds to the GCC 'pure' attribute. 3143e295b1b59e47916c8ae5d42eb27a23bd580cabeChris Lattner /// 31579fca6fea87be7221843031870bbf2c9ae1fc555Dan Gohman bool onlyReadsMemory(ImmutableCallSite CS) { 316467a0adfc8b6bd4b114e024c200c159497a4cd86Dan Gohman return onlyReadsMemory(getModRefBehavior(CS)); 317dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands } 318dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands 319dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// onlyReadsMemory - If the specified function is known to only read from 320dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// non-volatile memory (or not access memory at all), return true. For use 321dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// when the call site is not known. 322dff6710717b159f089c76a07eda074eb6347eb92Duncan Sands /// 32379fca6fea87be7221843031870bbf2c9ae1fc555Dan Gohman bool onlyReadsMemory(const Function *F) { 324467a0adfc8b6bd4b114e024c200c159497a4cd86Dan Gohman return onlyReadsMemory(getModRefBehavior(F)); 325467a0adfc8b6bd4b114e024c200c159497a4cd86Dan Gohman } 326467a0adfc8b6bd4b114e024c200c159497a4cd86Dan Gohman 327432d08cbdb9ceaa333f1d6eab4f8b542fdddf9dbDan Gohman /// onlyReadsMemory - Return true if functions with the specified behavior are 328432d08cbdb9ceaa333f1d6eab4f8b542fdddf9dbDan Gohman /// known to only read from non-volatile memory (or not access memory at all). 329467a0adfc8b6bd4b114e024c200c159497a4cd86Dan Gohman /// 330467a0adfc8b6bd4b114e024c200c159497a4cd86Dan Gohman static bool onlyReadsMemory(ModRefBehavior MRB) { 33142c31a70735e55bf82e66a9315c97d1821c9a798Dan Gohman return !(MRB & Mod); 332248e8ebeff834db9b78917b1531eeee7035eb113Chris Lattner } 3334df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 334432d08cbdb9ceaa333f1d6eab4f8b542fdddf9dbDan Gohman /// onlyAccessesArgPointees - Return true if functions with the specified 335b395e4a0262c36b17b18aa33514b2daf2a85e9a3Dan Gohman /// behavior are known to read and write at most from objects pointed to by 336b395e4a0262c36b17b18aa33514b2daf2a85e9a3Dan Gohman /// their pointer-typed arguments (with arbitrary offsets). 337432d08cbdb9ceaa333f1d6eab4f8b542fdddf9dbDan Gohman /// 338432d08cbdb9ceaa333f1d6eab4f8b542fdddf9dbDan Gohman static bool onlyAccessesArgPointees(ModRefBehavior MRB) { 339432d08cbdb9ceaa333f1d6eab4f8b542fdddf9dbDan Gohman return !(MRB & Anywhere & ~ArgumentPointees); 340432d08cbdb9ceaa333f1d6eab4f8b542fdddf9dbDan Gohman } 341432d08cbdb9ceaa333f1d6eab4f8b542fdddf9dbDan Gohman 34268a6056dafd4913ce42606353ab1ff7208215ff2Dan Gohman /// doesAccessArgPointees - Return true if functions with the specified 34356169787dbfb6d0b422ef114889b481e977b8996Nick Lewycky /// behavior are known to potentially read or write from objects pointed 34468a6056dafd4913ce42606353ab1ff7208215ff2Dan Gohman /// to be their pointer-typed arguments (with arbitrary offsets). 34568a6056dafd4913ce42606353ab1ff7208215ff2Dan Gohman /// 34668a6056dafd4913ce42606353ab1ff7208215ff2Dan Gohman static bool doesAccessArgPointees(ModRefBehavior MRB) { 34768a6056dafd4913ce42606353ab1ff7208215ff2Dan Gohman return (MRB & ModRef) && (MRB & ArgumentPointees); 34868a6056dafd4913ce42606353ab1ff7208215ff2Dan Gohman } 34968a6056dafd4913ce42606353ab1ff7208215ff2Dan Gohman 3501c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// getModRefInfo - Return information about whether or not an instruction may 351b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// read or write the specified memory location. An instruction 3521c56b730a6313886076d7b293a126ae5576f5288Chris Lattner /// that doesn't read or write memory may be trivially LICM'd for example. 353fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman ModRefResult getModRefInfo(const Instruction *I, 354b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman const Location &Loc) { 355fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman switch (I->getOpcode()) { 356b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman case Instruction::VAArg: return getModRefInfo((const VAArgInst*)I, Loc); 357b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman case Instruction::Load: return getModRefInfo((const LoadInst*)I, Loc); 358b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman case Instruction::Store: return getModRefInfo((const StoreInst*)I, Loc); 3598a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman case Instruction::Fence: return getModRefInfo((const FenceInst*)I, Loc); 36055ba816883842e793cdeb32fcb805c4e011b527fEli Friedman case Instruction::AtomicCmpXchg: 36155ba816883842e793cdeb32fcb805c4e011b527fEli Friedman return getModRefInfo((const AtomicCmpXchgInst*)I, Loc); 36255ba816883842e793cdeb32fcb805c4e011b527fEli Friedman case Instruction::AtomicRMW: 36355ba816883842e793cdeb32fcb805c4e011b527fEli Friedman return getModRefInfo((const AtomicRMWInst*)I, Loc); 364b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman case Instruction::Call: return getModRefInfo((const CallInst*)I, Loc); 365b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman case Instruction::Invoke: return getModRefInfo((const InvokeInst*)I,Loc); 366fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman default: return NoModRef; 367fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman } 368fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman } 3691c56b730a6313886076d7b293a126ae5576f5288Chris Lattner 370b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// getModRefInfo - A convenience wrapper. 371b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman ModRefResult getModRefInfo(const Instruction *I, 3723da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman const Value *P, uint64_t Size) { 373b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(I, Location(P, Size)); 374b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 375b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 3762bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for call sites) - Return information about whether 377b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// a particular call site modifies or reads the specified memory location. 37879fca6fea87be7221843031870bbf2c9ae1fc555Dan Gohman virtual ModRefResult getModRefInfo(ImmutableCallSite CS, 379b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman const Location &Loc); 380b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 381b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// getModRefInfo (for call sites) - A convenience wrapper. 382b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman ModRefResult getModRefInfo(ImmutableCallSite CS, 3833da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman const Value *P, uint64_t Size) { 384b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(CS, Location(P, Size)); 385b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 3861c56b730a6313886076d7b293a126ae5576f5288Chris Lattner 3872bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for calls) - Return information about whether 388b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// a particular call modifies or reads the specified memory location. 389b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman ModRefResult getModRefInfo(const CallInst *C, const Location &Loc) { 390b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(ImmutableCallSite(C), Loc); 391b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 392b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 393b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// getModRefInfo (for calls) - A convenience wrapper. 3943da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman ModRefResult getModRefInfo(const CallInst *C, const Value *P, uint64_t Size) { 395b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(C, Location(P, Size)); 3961c56b730a6313886076d7b293a126ae5576f5288Chris Lattner } 397fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman 3982bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for invokes) - Return information about whether 399b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// a particular invoke modifies or reads the specified memory location. 400b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman ModRefResult getModRefInfo(const InvokeInst *I, 401b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman const Location &Loc) { 402b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(ImmutableCallSite(I), Loc); 403b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 404b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 405b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// getModRefInfo (for invokes) - A convenience wrapper. 40679fca6fea87be7221843031870bbf2c9ae1fc555Dan Gohman ModRefResult getModRefInfo(const InvokeInst *I, 4073da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman const Value *P, uint64_t Size) { 408b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(I, Location(P, Size)); 4091c56b730a6313886076d7b293a126ae5576f5288Chris Lattner } 410fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman 4112bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for loads) - Return information about whether 412b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// a particular load modifies or reads the specified memory location. 413b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman ModRefResult getModRefInfo(const LoadInst *L, const Location &Loc); 414b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 415b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// getModRefInfo (for loads) - A convenience wrapper. 4163da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman ModRefResult getModRefInfo(const LoadInst *L, const Value *P, uint64_t Size) { 417b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(L, Location(P, Size)); 418b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 419fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman 4202bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for stores) - Return information about whether 421b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// a particular store modifies or reads the specified memory location. 422b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman ModRefResult getModRefInfo(const StoreInst *S, const Location &Loc); 423b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 424b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// getModRefInfo (for stores) - A convenience wrapper. 4252feee6454d4c9cbb3a104b0f593d31a91a14d15aChris Lattner ModRefResult getModRefInfo(const StoreInst *S, const Value *P, uint64_t Size){ 426b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(S, Location(P, Size)); 427b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 428fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman 4292bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for fences) - Return information about whether 4308a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman /// a particular store modifies or reads the specified memory location. 4318a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman ModRefResult getModRefInfo(const FenceInst *S, const Location &Loc) { 4328a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman // Conservatively correct. (We could possibly be a bit smarter if 4338a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman // Loc is a alloca that doesn't escape.) 4348a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman return ModRef; 4358a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman } 4368a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman 4378a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman /// getModRefInfo (for fences) - A convenience wrapper. 4388a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman ModRefResult getModRefInfo(const FenceInst *S, const Value *P, uint64_t Size){ 4398a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman return getModRefInfo(S, Location(P, Size)); 4408a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman } 4418a552bb85a5e9a6c250c0a899941fbd3ae7b5006Eli Friedman 4422bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for cmpxchges) - Return information about whether 44355ba816883842e793cdeb32fcb805c4e011b527fEli Friedman /// a particular cmpxchg modifies or reads the specified memory location. 44446cb5afdcd031c371c78201fb34291d9d48b2ee4Eli Friedman ModRefResult getModRefInfo(const AtomicCmpXchgInst *CX, const Location &Loc); 44555ba816883842e793cdeb32fcb805c4e011b527fEli Friedman 44655ba816883842e793cdeb32fcb805c4e011b527fEli Friedman /// getModRefInfo (for cmpxchges) - A convenience wrapper. 44755ba816883842e793cdeb32fcb805c4e011b527fEli Friedman ModRefResult getModRefInfo(const AtomicCmpXchgInst *CX, 44855ba816883842e793cdeb32fcb805c4e011b527fEli Friedman const Value *P, unsigned Size) { 44955ba816883842e793cdeb32fcb805c4e011b527fEli Friedman return getModRefInfo(CX, Location(P, Size)); 45055ba816883842e793cdeb32fcb805c4e011b527fEli Friedman } 45155ba816883842e793cdeb32fcb805c4e011b527fEli Friedman 4522bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for atomicrmws) - Return information about whether 45355ba816883842e793cdeb32fcb805c4e011b527fEli Friedman /// a particular atomicrmw modifies or reads the specified memory location. 45446cb5afdcd031c371c78201fb34291d9d48b2ee4Eli Friedman ModRefResult getModRefInfo(const AtomicRMWInst *RMW, const Location &Loc); 45555ba816883842e793cdeb32fcb805c4e011b527fEli Friedman 45655ba816883842e793cdeb32fcb805c4e011b527fEli Friedman /// getModRefInfo (for atomicrmws) - A convenience wrapper. 45755ba816883842e793cdeb32fcb805c4e011b527fEli Friedman ModRefResult getModRefInfo(const AtomicRMWInst *RMW, 45855ba816883842e793cdeb32fcb805c4e011b527fEli Friedman const Value *P, unsigned Size) { 45955ba816883842e793cdeb32fcb805c4e011b527fEli Friedman return getModRefInfo(RMW, Location(P, Size)); 46055ba816883842e793cdeb32fcb805c4e011b527fEli Friedman } 46155ba816883842e793cdeb32fcb805c4e011b527fEli Friedman 4622bf786af90b8c3826974b2a9deea5e8081ebf113Sean Silva /// getModRefInfo (for va_args) - Return information about whether 463b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// a particular va_arg modifies or reads the specified memory location. 464b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman ModRefResult getModRefInfo(const VAArgInst* I, const Location &Loc); 465b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 466b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// getModRefInfo (for va_args) - A convenience wrapper. 4672feee6454d4c9cbb3a104b0f593d31a91a14d15aChris Lattner ModRefResult getModRefInfo(const VAArgInst* I, const Value* P, uint64_t Size){ 468b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return getModRefInfo(I, Location(P, Size)); 469b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 470fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman 471fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman /// getModRefInfo - Return information about whether two call sites may refer 472fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman /// to the same set of memory locations. See 473fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman /// http://llvm.org/docs/AliasAnalysis.html#ModRefInfo 474fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman /// for details. 475fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman virtual ModRefResult getModRefInfo(ImmutableCallSite CS1, 476fa6cb8d8211579f1370e80b7bac54ebe3fbe35c8Dan Gohman ImmutableCallSite CS2); 4774df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 4783a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier /// callCapturesBefore - Return information about whether a particular call 4793a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier /// site modifies or reads the specified memory location. 4803a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier ModRefResult callCapturesBefore(const Instruction *I, 4813a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier const AliasAnalysis::Location &MemLoc, 4823a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier DominatorTree *DT); 4833a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier 4843a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier /// callCapturesBefore - A convenience wrapper. 4853a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier ModRefResult callCapturesBefore(const Instruction *I, const Value *P, 4863a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier uint64_t Size, DominatorTree *DT) { 4873a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier return callCapturesBefore(I, Location(P, Size), DT); 4883a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier } 4893a884f5c17ac32e34e7e62b4602a0d73eeda1ce8Chad Rosier 490ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner //===--------------------------------------------------------------------===// 491ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// Higher level methods for querying mod/ref information. 492ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// 493ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner 494f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// canBasicBlockModify - Return true if it is possible for execution of the 495f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// specified basic block to modify the value pointed to by Ptr. 496b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman bool canBasicBlockModify(const BasicBlock &BB, const Location &Loc); 497b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 498b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// canBasicBlockModify - A convenience wrapper. 4993da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman bool canBasicBlockModify(const BasicBlock &BB, const Value *P, uint64_t Size){ 500b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return canBasicBlockModify(BB, Location(P, Size)); 501b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 5024df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 503f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// canInstructionRangeModify - Return true if it is possible for the 504f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// execution of the specified instructions to modify the value pointed to by 505f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// Ptr. The instructions to consider are all of the instructions in the 506f12c2c28bd72091f2d7fff5718265c5ad52e7af8Chris Lattner /// range of [I1,I2] INCLUSIVE. I1 and I2 must be in the same basic block. 5074df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner bool canInstructionRangeModify(const Instruction &I1, const Instruction &I2, 508b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman const Location &Loc); 509b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman 510b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman /// canInstructionRangeModify - A convenience wrapper. 511b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman bool canInstructionRangeModify(const Instruction &I1, const Instruction &I2, 5123da848bbda62b25c12335998aaa44ab361f0bf15Dan Gohman const Value *Ptr, uint64_t Size) { 513b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman return canInstructionRangeModify(I1, I2, Location(Ptr, Size)); 514b2143b6247901ae4eca2192ee134564c4f5f7853Dan Gohman } 515ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner 516ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner //===--------------------------------------------------------------------===// 517ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// Methods that clients should call when they transform the program to allow 518ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// alias analyses to update their internal data structures. Note that these 519ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// methods may be called on any instruction, regardless of whether or not 520ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// they have pointer-analysis implications. 521ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// 522ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner 523ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// deleteValue - This method should be called whenever an LLVM Value is 524ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// deleted from the program, for example when an instruction is found to be 525ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// redundant and is eliminated. 526ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// 527ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner virtual void deleteValue(Value *V); 528ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner 529ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// copyValue - This method should be used whenever a preexisting value in the 530ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// program is copied or cloned, introducing a new value. Note that analysis 531ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// implementations should tolerate clients that use this method to introduce 532ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// the same value multiple times: if the analysis already knows about a 533ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// value, it should ignore the request. 534ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// 535ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner virtual void copyValue(Value *From, Value *To); 536ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner 537ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// addEscapingUse - This method should be used whenever an escaping use is 538ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// added to a pointer value. Analysis implementations may either return 539ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// conservative responses for that value in the future, or may recompute 540ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// some or all internal state to continue providing precise responses. 541ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// 542ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// Escaping uses are considered by anything _except_ the following: 543ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// - GEPs or bitcasts of the pointer 544ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// - Loads through the pointer 545ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson /// - Stores through (but not of) the pointer 546ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson virtual void addEscapingUse(Use &U); 547ab6acc6ecdc4585a55059e36d81481d1c26d3ff9Owen Anderson 548ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// replaceWithNewValue - This method is the obvious combination of the two 549ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// above, and it provided as a helper to simplify client code. 550ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner /// 551ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner void replaceWithNewValue(Value *Old, Value *New) { 552ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner copyValue(Old, New); 553ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner deleteValue(Old); 554ab8c565768ff7485f40cbb65e2914f9046e743d4Chris Lattner } 5554df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner}; 5564df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner 5571fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman// Specialize DenseMapInfo for Location. 5581fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohmantemplate<> 5591fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohmanstruct DenseMapInfo<AliasAnalysis::Location> { 5601fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman static inline AliasAnalysis::Location getEmptyKey() { 5611fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman return 5621fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman AliasAnalysis::Location(DenseMapInfo<const Value *>::getEmptyKey(), 5631fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman 0, 0); 5641fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman } 5651fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman static inline AliasAnalysis::Location getTombstoneKey() { 5661fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman return 5671fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman AliasAnalysis::Location(DenseMapInfo<const Value *>::getTombstoneKey(), 5681fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman 0, 0); 5691fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman } 5701fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman static unsigned getHashValue(const AliasAnalysis::Location &Val) { 5711fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman return DenseMapInfo<const Value *>::getHashValue(Val.Ptr) ^ 5721fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman DenseMapInfo<uint64_t>::getHashValue(Val.Size) ^ 5731fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman DenseMapInfo<const MDNode *>::getHashValue(Val.TBAATag); 5741fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman } 5751fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman static bool isEqual(const AliasAnalysis::Location &LHS, 5761fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman const AliasAnalysis::Location &RHS) { 5771fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman return LHS.Ptr == RHS.Ptr && 5781fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman LHS.Size == RHS.Size && 5791fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman LHS.TBAATag == RHS.TBAATag; 5801fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman } 5811fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman}; 5821fc18d71deb0e23a9101c87bb7b1455098ce1c09Dan Gohman 583a5f81bba4ab18d6129774d4d67495f14b6f64375Dan Gohman/// isNoAliasCall - Return true if this pointer is returned by a noalias 584a5f81bba4ab18d6129774d4d67495f14b6f64375Dan Gohman/// function. 585a5f81bba4ab18d6129774d4d67495f14b6f64375Dan Gohmanbool isNoAliasCall(const Value *V); 586a5f81bba4ab18d6129774d4d67495f14b6f64375Dan Gohman 5879f5de6dadcdb9922ad8c8135a29e4abccec11671Michael Kuperstein/// isNoAliasArgument - Return true if this is an argument with the noalias 5889f5de6dadcdb9922ad8c8135a29e4abccec11671Michael Kuperstein/// attribute. 5899f5de6dadcdb9922ad8c8135a29e4abccec11671Michael Kupersteinbool isNoAliasArgument(const Value *V); 5909f5de6dadcdb9922ad8c8135a29e4abccec11671Michael Kuperstein 5913311a1f8f0d8a2c6d940802bbb95eba0b801a615Dan Gohman/// isIdentifiedObject - Return true if this pointer refers to a distinct and 592a5f81bba4ab18d6129774d4d67495f14b6f64375Dan Gohman/// identifiable object. This returns true for: 5935753a4a0033da4add45f2e9930a4e1159d92a869Dan Gohman/// Global Variables and Functions (but not Global Aliases) 594c63ee60ef030177fed0fea9212bc2f516fdf0796Dan Gohman/// Allocas 5959e86f4364b912ae743490ba01d6989acfd12c046Dan Gohman/// ByVal and NoAlias Arguments 596c63ee60ef030177fed0fea9212bc2f516fdf0796Dan Gohman/// NoAlias returns (e.g. calls to malloc) 5973311a1f8f0d8a2c6d940802bbb95eba0b801a615Dan Gohman/// 5989e86f4364b912ae743490ba01d6989acfd12c046Dan Gohmanbool isIdentifiedObject(const Value *V); 5993311a1f8f0d8a2c6d940802bbb95eba0b801a615Dan Gohman 6004f1bd9e9963239c119db70070db1d68286b3de7eReid Spencer} // End llvm namespace 6014f1bd9e9963239c119db70070db1d68286b3de7eReid Spencer 6024df22c0100fe27f19e6f4874f24eedd0742b9cf4Chris Lattner#endif 603