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-rw-r--r--lib/Analysis/BasicAliasAnalysis.cpp89
1 files changed, 8 insertions, 81 deletions
diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index 58244fc11c..669202f859 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -1,4 +1,4 @@
-//===- BasicAliasAnalysis.cpp - Local Alias Analysis Impl -----------------===//
+//===- BasicAliasAnalysis.cpp - Stateless Alias Analysis Impl -------------===//
//
// The LLVM Compiler Infrastructure
//
@@ -7,9 +7,9 @@
//
//===----------------------------------------------------------------------===//
//
-// This file defines the default implementation of the Alias Analysis interface
-// that simply implements a few identities (two different globals cannot alias,
-// etc), but otherwise does no analysis.
+// This file defines the primary stateless implementation of the
+// Alias Analysis interface that implements identities (two different
+// globals cannot alias, etc), but does no stateful analysis.
//
//===----------------------------------------------------------------------===//
@@ -129,74 +129,6 @@ static bool isObjectSmallerThan(const Value *V, uint64_t Size,
}
//===----------------------------------------------------------------------===//
-// NoAA Pass
-//===----------------------------------------------------------------------===//
-
-namespace {
- /// NoAA - This class implements the -no-aa pass, which always returns "I
- /// don't know" for alias queries. NoAA is unlike other alias analysis
- /// implementations, in that it does not chain to a previous analysis. As
- /// such it doesn't follow many of the rules that other alias analyses must.
- ///
- struct NoAA : public ImmutablePass, public AliasAnalysis {
- static char ID; // Class identification, replacement for typeinfo
- NoAA() : ImmutablePass(ID) {
- initializeNoAAPass(*PassRegistry::getPassRegistry());
- }
- explicit NoAA(char &PID) : ImmutablePass(PID) {}
-
- virtual void getAnalysisUsage(AnalysisUsage &AU) const {
- }
-
- virtual void initializePass() {
- TD = getAnalysisIfAvailable<TargetData>();
- }
-
- virtual AliasResult alias(const Location &LocA, const Location &LocB) {
- return MayAlias;
- }
-
- virtual ModRefBehavior getModRefBehavior(ImmutableCallSite CS) {
- return UnknownModRefBehavior;
- }
- virtual ModRefBehavior getModRefBehavior(const Function *F) {
- return UnknownModRefBehavior;
- }
-
- virtual bool pointsToConstantMemory(const Location &Loc) { return false; }
- virtual ModRefResult getModRefInfo(ImmutableCallSite CS,
- const Location &Loc) {
- return ModRef;
- }
- virtual ModRefResult getModRefInfo(ImmutableCallSite CS1,
- ImmutableCallSite CS2) {
- return ModRef;
- }
-
- virtual void deleteValue(Value *V) {}
- virtual void copyValue(Value *From, Value *To) {}
-
- /// getAdjustedAnalysisPointer - This method is used when a pass implements
- /// an analysis interface through multiple inheritance. If needed, it
- /// should override this to adjust the this pointer as needed for the
- /// specified pass info.
- virtual void *getAdjustedAnalysisPointer(const void *ID) {
- if (ID == &AliasAnalysis::ID)
- return (AliasAnalysis*)this;
- return this;
- }
- };
-} // End of anonymous namespace
-
-// Register this pass...
-char NoAA::ID = 0;
-INITIALIZE_AG_PASS(NoAA, AliasAnalysis, "no-aa",
- "No Alias Analysis (always returns 'may' alias)",
- true, true, true)
-
-ImmutablePass *llvm::createNoAAPass() { return new NoAA(); }
-
-//===----------------------------------------------------------------------===//
// GetElementPtr Instruction Decomposition and Analysis
//===----------------------------------------------------------------------===//
@@ -487,12 +419,10 @@ static bool notDifferentParent(const Value *O1, const Value *O2) {
#endif
namespace {
- /// BasicAliasAnalysis - This is the default alias analysis implementation.
- /// Because it doesn't chain to a previous alias analysis (like -no-aa), it
- /// derives from the NoAA class.
- struct BasicAliasAnalysis : public NoAA {
+ /// BasicAliasAnalysis - This is the primary alias analysis implementation.
+ struct BasicAliasAnalysis : public ImmutablePass, public AliasAnalysis {
static char ID; // Class identification, replacement for typeinfo
- BasicAliasAnalysis() : NoAA(ID) {
+ BasicAliasAnalysis() : ImmutablePass(ID) {
initializeBasicAliasAnalysisPass(*PassRegistry::getPassRegistry());
}
@@ -580,7 +510,7 @@ namespace {
// Register this pass...
char BasicAliasAnalysis::ID = 0;
INITIALIZE_AG_PASS(BasicAliasAnalysis, AliasAnalysis, "basicaa",
- "Basic Alias Analysis (default AA impl)",
+ "Basic Alias Analysis (stateless AA impl)",
false, true, false)
ImmutablePass *llvm::createBasicAliasAnalysisPass() {
@@ -1125,6 +1055,3 @@ BasicAliasAnalysis::aliasCheck(const Value *V1, uint64_t V1Size,
return AliasAnalysis::alias(Location(V1, V1Size, V1TBAAInfo),
Location(V2, V2Size, V2TBAAInfo));
}
-
-// Make sure that anything that uses AliasAnalysis pulls in this file.
-DEFINING_FILE_FOR(BasicAliasAnalysis)