//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
#include "llvm/Support/CallSite.h"
#include "llvm/System/IncludeFile.h"
+#include <vector>
namespace llvm {
///
void InitializeAliasAnalysis(Pass *P);
- // getAnalysisUsage - All alias analysis implementations should invoke this
- // directly (using AliasAnalysis::getAnalysisUsage(AU)) to make sure that
- // TargetData is required by the pass.
+ /// getAnalysisUsage - All alias analysis implementations should invoke this
+ /// directly (using AliasAnalysis::getAnalysisUsage(AU)).
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
public:
+ static char ID; // Class identification, replacement for typeinfo
AliasAnalysis() : TD(0), AA(0) {}
virtual ~AliasAnalysis(); // We want to be subclassed
- /// getTargetData - Every alias analysis implementation depends on the size of
- /// data items in the current Target. This provides a uniform way to handle
- /// it.
+ /// getTargetData - Return a pointer to the current TargetData object, or
+ /// null if no TargetData object is available.
///
- const TargetData &getTargetData() const { return *TD; }
+ const TargetData *getTargetData() const { return TD; }
+
+ /// getTypeStoreSize - Return the TargetData store size for the given type,
+ /// if known, or a conservative value otherwise.
+ ///
+ unsigned getTypeStoreSize(const Type *Ty);
//===--------------------------------------------------------------------===//
/// Alias Queries...
virtual AliasResult alias(const Value *V1, unsigned V1Size,
const Value *V2, unsigned V2Size);
- /// getMustAliases - If there are any pointers known that must alias this
- /// pointer, return them now. This allows alias-set based alias analyses to
- /// perform a form a value numbering (which is exposed by load-vn). If an
- /// alias analysis supports this, it should ADD any must aliased pointers to
- /// the specified vector.
- ///
- virtual void getMustAliases(Value *P, std::vector<Value*> &RetVals);
+ /// isNoAlias - A trivial helper function to check to see if the specified
+ /// pointers are no-alias.
+ bool isNoAlias(const Value *V1, unsigned V1Size,
+ const Value *V2, unsigned V2Size) {
+ return alias(V1, V1Size, V2, V2Size) == NoAlias;
+ }
/// pointsToConstantMemory - If the specified pointer is known to point into
/// constant global memory, return true. This allows disambiguation of store
// This property corresponds to the GCC 'const' attribute.
DoesNotAccessMemory,
- // AccessesArguments - This function accesses function arguments in
- // non-volatile and well known ways, but does not access any other memory.
+ // AccessesArguments - This function accesses function arguments in well
+ // known (possibly volatile) ways, but does not access any other memory.
//
- // Clients may call getArgumentAccesses to get specific information about
- // how pointer arguments are used.
+ // Clients may use the Info parameter of getModRefBehavior to get specific
+ // information about how pointer arguments are used.
AccessesArguments,
// AccessesArgumentsAndGlobals - This function has accesses function
- // arguments and global variables in non-volatile and well-known ways, but
+ // arguments and global variables well known (possibly volatile) ways, but
// does not access any other memory.
//
- // Clients may call getArgumentAccesses to get specific information about
- // how pointer arguments and globals are used.
+ // Clients may use the Info parameter of getModRefBehavior to get specific
+ // information about how pointer arguments are used.
AccessesArgumentsAndGlobals,
// OnlyReadsMemory - This function does not perform any non-local stores or
};
};
- /// getModRefBehavior - Return the behavior of the specified function if
- /// called from the specified call site. The call site may be null in which
- /// case the most generic behavior of this function should be returned.
- virtual ModRefBehavior getModRefBehavior(Function *F, CallSite CS,
- std::vector<PointerAccessInfo> *Info = 0);
+ /// getModRefBehavior - Return the behavior when calling the given call site.
+ virtual ModRefBehavior getModRefBehavior(CallSite CS,
+ std::vector<PointerAccessInfo> *Info = 0);
- /// doesNotAccessMemory - If the specified function is known to never read or
- /// write memory, return true. If the function only reads from known-constant
- /// memory, it is also legal to return true. Functions that unwind the stack
- /// are not legal for this predicate.
+ /// getModRefBehavior - Return the behavior when calling the given function.
+ /// For use when the call site is not known.
+ virtual ModRefBehavior getModRefBehavior(Function *F,
+ std::vector<PointerAccessInfo> *Info = 0);
+
+ /// getModRefBehavior - Return the modref behavior of the intrinsic with the
+ /// given id.
+ static ModRefBehavior getModRefBehavior(unsigned iid);
+
+ /// doesNotAccessMemory - If the specified call is known to never read or
+ /// write memory, return true. If the call only reads from known-constant
+ /// memory, it is also legal to return true. Calls that unwind the stack
+ /// are legal for this predicate.
///
- /// Many optimizations (such as CSE and LICM) can be performed on calls to it,
- /// without worrying about aliasing properties, and many functions have this
- /// property (e.g. 'sin' and 'cos').
+ /// Many optimizations (such as CSE and LICM) can be performed on such calls
+ /// without worrying about aliasing properties, and many calls have this
+ /// property (e.g. calls to 'sin' and 'cos').
///
/// This property corresponds to the GCC 'const' attribute.
///
+ bool doesNotAccessMemory(CallSite CS) {
+ return getModRefBehavior(CS) == DoesNotAccessMemory;
+ }
+
+ /// doesNotAccessMemory - If the specified function is known to never read or
+ /// write memory, return true. For use when the call site is not known.
+ ///
bool doesNotAccessMemory(Function *F) {
- return getModRefBehavior(F, CallSite()) == DoesNotAccessMemory;
+ return getModRefBehavior(F) == DoesNotAccessMemory;
}
- /// onlyReadsMemory - If the specified function is known to only read from
- /// non-volatile memory (or not access memory at all), return true. Functions
- /// that unwind the stack are not legal for this predicate.
+ /// onlyReadsMemory - If the specified call is known to only read from
+ /// non-volatile memory (or not access memory at all), return true. Calls
+ /// that unwind the stack are legal for this predicate.
///
/// This property allows many common optimizations to be performed in the
/// absence of interfering store instructions, such as CSE of strlen calls.
///
/// This property corresponds to the GCC 'pure' attribute.
///
+ bool onlyReadsMemory(CallSite CS) {
+ ModRefBehavior MRB = getModRefBehavior(CS);
+ return MRB == DoesNotAccessMemory || MRB == OnlyReadsMemory;
+ }
+
+ /// onlyReadsMemory - If the specified function is known to only read from
+ /// non-volatile memory (or not access memory at all), return true. For use
+ /// when the call site is not known.
+ ///
bool onlyReadsMemory(Function *F) {
- /// FIXME: If the analysis returns more precise info, we can reduce it to
- /// this.
- ModRefBehavior MRB = getModRefBehavior(F, CallSite());
+ ModRefBehavior MRB = getModRefBehavior(F);
return MRB == DoesNotAccessMemory || MRB == OnlyReadsMemory;
}
///
virtual ModRefResult getModRefInfo(CallSite CS1, CallSite CS2);
- /// hasNoModRefInfoForCalls - Return true if the analysis has no mod/ref
- /// information for pairs of function calls (other than "pure" and "const"
- /// functions). This can be used by clients to avoid many pointless queries.
- /// Remember that if you override this and chain to another analysis, you must
- /// make sure that it doesn't have mod/ref info either.
- ///
- virtual bool hasNoModRefInfoForCalls() const;
-
+public:
/// Convenience functions...
ModRefResult getModRefInfo(LoadInst *L, Value *P, unsigned Size);
ModRefResult getModRefInfo(StoreInst *S, Value *P, unsigned Size);
return getModRefInfo(CallSite(I), P, Size);
}
ModRefResult getModRefInfo(VAArgInst* I, Value* P, unsigned Size) {
- return AliasAnalysis::Mod;
+ return AliasAnalysis::ModRef;
}
ModRefResult getModRefInfo(Instruction *I, Value *P, unsigned Size) {
switch (I->getOpcode()) {
}
};
+/// isNoAliasCall - Return true if this pointer is returned by a noalias
+/// function.
+bool isNoAliasCall(const Value *V);
+
+/// isIdentifiedObject - Return true if this pointer refers to a distinct and
+/// identifiable object. This returns true for:
+/// Global Variables and Functions (but not Global Aliases)
+/// Allocas and Mallocs
+/// ByVal and NoAlias Arguments
+/// NoAlias returns
+///
+bool isIdentifiedObject(const Value *V);
+
} // End llvm namespace
// Because of the way .a files work, we must force the BasicAA implementation to
projects / oota-llvm.git / blobdiff