6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-09-24 23:28:41 +00:00
Code Issues Projects Releases Wiki Activity

Remove the experimental AliasAnalysis::getDependency interface, which

Browse Source 
isn't a good level of abstraction for memdep. Instead, generalize
AliasAnalysis::alias and related interfaces with a new Location
class for describing a memory location. For now, this is the same
Pointer and Size as before, plus an additional field for a TBAA tag.

Also, introduce a fixed MD_tbaa metadata tag kind.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113858 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman
2010-09-14 21:25:10 +00:00
parent fe3ac088ee
commit b2143b6247
13 changed files with 258 additions and 512 deletions
Download Patch File Download Diff File Expand all files Collapse all files

239
include/llvm/Analysis/AliasAnalysis.h
View File

@@ -83,6 +83,22 @@ public:
/// Alias Queries... /// Alias Queries...
/// ///
/// Location - A description of a memory location.
struct Location {
/// Ptr - The address of the start of the location.
const Value *Ptr;
/// Size - The size of the location.
unsigned Size;
/// TBAATag - The metadata node which describes the TBAA type of
/// the location, or null if there is no (unique) tag.
const MDNode *TBAATag;
explicit Location(const Value *P = 0,
unsigned S = UnknownSize,
const MDNode *N = 0)
: Ptr(P), Size(S), TBAATag(N) {}
};
/// Alias analysis result - Either we know for sure that it does not alias, we /// Alias analysis result - Either we know for sure that it does not alias, we
/// know for sure it must alias, or we don't know anything: The two pointers /// know for sure it must alias, or we don't know anything: The two pointers
/// _might_ alias. This enum is designed so you can do things like: /// _might_ alias. This enum is designed so you can do things like:
@@ -98,27 +114,41 @@ public:
/// Returns a Result indicating whether the two pointers are aliased to each /// Returns a Result indicating whether the two pointers are aliased to each
/// other. This is the interface that must be implemented by specific alias /// other. This is the interface that must be implemented by specific alias
/// analysis implementations. /// analysis implementations.
/// virtual AliasResult alias(const Location &LocA, const Location &LocB);
virtual AliasResult alias(const Value *V1, unsigned V1Size,
const Value *V2, unsigned V2Size);
/// alias - A convenience wrapper for the case where the sizes are unknown. /// alias - A convenience wrapper.
AliasResult alias(const Value *V1, unsigned V1Size,
const Value *V2, unsigned V2Size) {
return alias(Location(V1, V1Size), Location(V2, V2Size));
}
/// alias - A convenience wrapper.
AliasResult alias(const Value *V1, const Value *V2) { AliasResult alias(const Value *V1, const Value *V2) {
return alias(V1, UnknownSize, V2, UnknownSize); return alias(V1, UnknownSize, V2, UnknownSize);
} }
/// isNoAlias - A trivial helper function to check to see if the specified /// isNoAlias - A trivial helper function to check to see if the specified
/// pointers are no-alias. /// pointers are no-alias.
bool isNoAlias(const Value *V1, unsigned V1Size, bool isNoAlias(const Location &LocA, const Location &LocB) {
const Value *V2, unsigned V2Size) { return alias(LocA, LocB) == NoAlias;
return alias(V1, V1Size, V2, V2Size) == NoAlias;
} }
/// pointsToConstantMemory - If the specified pointer is known to point into /// isNoAlias - A convenience wrapper.
/// constant global memory, return true. This allows disambiguation of store bool isNoAlias(const Value *V1, unsigned V1Size,
const Value *V2, unsigned V2Size) {
return isNoAlias(Location(V1, V1Size), Location(V2, V2Size));
}
/// pointsToConstantMemory - If the specified memory location is known to be
/// constant, return true. This allows disambiguation of store
/// instructions from constant pointers. /// instructions from constant pointers.
/// ///
virtual bool pointsToConstantMemory(const Value *P); virtual bool pointsToConstantMemory(const Location &Loc);
/// pointsToConstantMemory - A convenient wrapper.
bool pointsToConstantMemory(const Value *P) {
return pointsToConstantMemory(Location(P));
}
//===--------------------------------------------------------------------===// //===--------------------------------------------------------------------===//
/// Simple mod/ref information... /// Simple mod/ref information...
@@ -220,55 +250,87 @@ public:
/// getModRefInfo - Return information about whether or not an instruction may /// getModRefInfo - Return information about whether or not an instruction may
/// read or write memory specified by the pointer operand. An instruction /// read or write the specified memory location. An instruction
/// that doesn't read or write memory may be trivially LICM'd for example. /// that doesn't read or write memory may be trivially LICM'd for example.
ModRefResult getModRefInfo(const Instruction *I, ModRefResult getModRefInfo(const Instruction *I,
const Value *P, unsigned Size) { const Location &Loc) {
switch (I->getOpcode()) { switch (I->getOpcode()) {
case Instruction::VAArg: return getModRefInfo((const VAArgInst*)I, P,Size); case Instruction::VAArg: return getModRefInfo((const VAArgInst*)I, Loc);
case Instruction::Load: return getModRefInfo((const LoadInst*)I, P, Size); case Instruction::Load: return getModRefInfo((const LoadInst*)I, Loc);
case Instruction::Store: return getModRefInfo((const StoreInst*)I, P,Size); case Instruction::Store: return getModRefInfo((const StoreInst*)I, Loc);
case Instruction::Call: return getModRefInfo((const CallInst*)I, P, Size); case Instruction::Call: return getModRefInfo((const CallInst*)I, Loc);
case Instruction::Invoke: return getModRefInfo((const InvokeInst*)I,P,Size); case Instruction::Invoke: return getModRefInfo((const InvokeInst*)I,Loc);
default: return NoModRef; default: return NoModRef;
} }
} }
/// getModRefInfo - A convenience wrapper.
ModRefResult getModRefInfo(const Instruction *I,
const Value *P, unsigned Size) {
return getModRefInfo(I, Location(P, Size));
}
/// getModRefInfo (for call sites) - Return whether information about whether /// getModRefInfo (for call sites) - Return whether information about whether
/// a particular call site modifies or reads the memory specified by the /// a particular call site modifies or reads the specified memory location.
/// pointer.
virtual ModRefResult getModRefInfo(ImmutableCallSite CS, virtual ModRefResult getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size); const Location &Loc);
/// getModRefInfo (for call sites) - A convenience wrapper.
ModRefResult getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size) {
return getModRefInfo(CS, Location(P, Size));
}
/// getModRefInfo (for calls) - Return whether information about whether /// getModRefInfo (for calls) - Return whether information about whether
/// a particular call modifies or reads the memory specified by the /// a particular call modifies or reads the specified memory location.
/// pointer. ModRefResult getModRefInfo(const CallInst *C, const Location &Loc) {
return getModRefInfo(ImmutableCallSite(C), Loc);
}
/// getModRefInfo (for calls) - A convenience wrapper.
ModRefResult getModRefInfo(const CallInst *C, const Value *P, unsigned Size) { ModRefResult getModRefInfo(const CallInst *C, const Value *P, unsigned Size) {
return getModRefInfo(ImmutableCallSite(C), P, Size); return getModRefInfo(C, Location(P, Size));
} }
/// getModRefInfo (for invokes) - Return whether information about whether /// getModRefInfo (for invokes) - Return whether information about whether
/// a particular invoke modifies or reads the memory specified by the /// a particular invoke modifies or reads the specified memory location.
/// pointer. ModRefResult getModRefInfo(const InvokeInst *I,
const Location &Loc) {
return getModRefInfo(ImmutableCallSite(I), Loc);
}
/// getModRefInfo (for invokes) - A convenience wrapper.
ModRefResult getModRefInfo(const InvokeInst *I, ModRefResult getModRefInfo(const InvokeInst *I,
const Value *P, unsigned Size) { const Value *P, unsigned Size) {
return getModRefInfo(ImmutableCallSite(I), P, Size); return getModRefInfo(I, Location(P, Size));
} }
/// getModRefInfo (for loads) - Return whether information about whether /// getModRefInfo (for loads) - Return whether information about whether
/// a particular load modifies or reads the memory specified by the /// a particular load modifies or reads the specified memory location.
/// pointer. ModRefResult getModRefInfo(const LoadInst *L, const Location &Loc);
ModRefResult getModRefInfo(const LoadInst *L, const Value *P, unsigned Size);
/// getModRefInfo (for loads) - A convenience wrapper.
ModRefResult getModRefInfo(const LoadInst *L, const Value *P, unsigned Size) {
return getModRefInfo(L, Location(P, Size));
}
/// getModRefInfo (for stores) - Return whether information about whether /// getModRefInfo (for stores) - Return whether information about whether
/// a particular store modifies or reads the memory specified by the /// a particular store modifies or reads the specified memory location.
/// pointer. ModRefResult getModRefInfo(const StoreInst *S, const Location &Loc);
ModRefResult getModRefInfo(const StoreInst *S, const Value *P, unsigned Size);
/// getModRefInfo (for stores) - A convenience wrapper.
ModRefResult getModRefInfo(const StoreInst *S, const Value *P, unsigned Size) {
return getModRefInfo(S, Location(P, Size));
}
/// getModRefInfo (for va_args) - Return whether information about whether /// getModRefInfo (for va_args) - Return whether information about whether
/// a particular va_arg modifies or reads the memory specified by the /// a particular va_arg modifies or reads the specified memory location.
/// pointer. ModRefResult getModRefInfo(const VAArgInst* I, const Location &Loc);
ModRefResult getModRefInfo(const VAArgInst* I, const Value* P, unsigned Size);
/// getModRefInfo (for va_args) - A convenience wrapper.
ModRefResult getModRefInfo(const VAArgInst* I, const Value* P, unsigned Size) {
return getModRefInfo(I, Location(P, Size));
}
/// getModRefInfo - Return information about whether two call sites may refer /// getModRefInfo - Return information about whether two call sites may refer
/// to the same set of memory locations. See /// to the same set of memory locations. See
@@ -277,101 +339,31 @@ public:
virtual ModRefResult getModRefInfo(ImmutableCallSite CS1, virtual ModRefResult getModRefInfo(ImmutableCallSite CS1,
ImmutableCallSite CS2); ImmutableCallSite CS2);
//===--------------------------------------------------------------------===//
/// Dependence queries.
///
/// DependenceResult - These are the return values for getDependence queries.
/// They are defined in terms of "memory", but they are also used to model
/// other side effects, such as I/O and volatility.
enum DependenceResult {
/// ReadThenRead - The instructions are ReadThenReadSome and the second
/// instruction reads from exactly the same memory read from by the first.
ReadThenRead,
/// ReadThenReadSome - The instructions are Independent, both are read-only,
/// and the second instruction reads from a subset of the memory read from
/// by the first.
ReadThenReadSome,
/// Independent - Neither instruction reads from or writes to memory written
/// to by the other. All enum values lower than this one are special cases
/// of Indepenent.
Independent,
/// WriteThenRead - The instructions are WriteThenReadSome and the second
/// instruction reads from exactly the same memory written by the first.
WriteThenRead,
/// WriteThenReadSome - The first instruction is write-only, the second
/// instruction is read-only, and the second only reads from memory
/// written to by the first.
WriteThenReadSome,
/// ReadThenWrite - The first instruction is read-only, the second
/// instruction is write-only, and the second wrotes to exactly the
/// same memory read from by the first.
ReadThenWrite,
/// WriteThenWrite - The instructions are WriteThenWriteSome, and the
/// second instruction writes to exactly the same memory written to by
/// the first.
WriteThenWrite,
/// WriteSomeThenWrite - Both instructions are write-only, and the second
/// instruction writes to a superset of the memory written to by the first.
WriteSomeThenWrite,
/// Unknown - The relationship between the instructions cannot be
/// determined or does not fit into any of the cases defined here.
Unknown
};
/// DependenceQueryFlags - Flags for refining dependence queries.
enum DependenceQueryFlags {
Default = 0,
IgnoreLoads = 1,
IgnoreStores = 2
};
/// getDependence - Determine the dependence relationship between the
/// instructions. This does not include "register" dependencies; it just
/// considers memory references and other side effects.
/// WARNING: This is an experimental interface.
DependenceResult getDependence(const Instruction *First,
const Instruction *Second) {
return getDependence(First, 0, Default, Second, 0, Default);
}
/// getDependence - Determine the dependence relationship between the
/// instructions. This does not include "register" dependencies; it just
/// considers memory references and other side effects. This overload
/// has additional parameters to allow phi-translated addresses to be
/// specified, and additional flags to refine the query.
/// WARNING: This is an experimental interface.
virtual DependenceResult getDependence(const Instruction *First,
const Value *FirstPHITranslatedAddr,
DependenceQueryFlags FirstFlags,
const Instruction *Second,
const Value *SecondPHITranslatedAddr,
DependenceQueryFlags SecondFlags);
//===--------------------------------------------------------------------===// //===--------------------------------------------------------------------===//
/// Higher level methods for querying mod/ref information. /// Higher level methods for querying mod/ref information.
/// ///
/// canBasicBlockModify - Return true if it is possible for execution of the /// canBasicBlockModify - Return true if it is possible for execution of the
/// specified basic block to modify the value pointed to by Ptr. /// specified basic block to modify the value pointed to by Ptr.
/// bool canBasicBlockModify(const BasicBlock &BB, const Location &Loc);
bool canBasicBlockModify(const BasicBlock &BB, const Value *P, unsigned Size);
/// canBasicBlockModify - A convenience wrapper.
bool canBasicBlockModify(const BasicBlock &BB, const Value *P, unsigned Size){
return canBasicBlockModify(BB, Location(P, Size));
}
/// canInstructionRangeModify - Return true if it is possible for the /// canInstructionRangeModify - Return true if it is possible for the
/// execution of the specified instructions to modify the value pointed to by /// execution of the specified instructions to modify the value pointed to by
/// Ptr. The instructions to consider are all of the instructions in the /// Ptr. The instructions to consider are all of the instructions in the
/// range of [I1,I2] INCLUSIVE. I1 and I2 must be in the same basic block. /// range of [I1,I2] INCLUSIVE. I1 and I2 must be in the same basic block.
///
bool canInstructionRangeModify(const Instruction &I1, const Instruction &I2, bool canInstructionRangeModify(const Instruction &I1, const Instruction &I2,
const Value *Ptr, unsigned Size); const Location &Loc);
/// canInstructionRangeModify - A convenience wrapper.
bool canInstructionRangeModify(const Instruction &I1, const Instruction &I2,
const Value *Ptr, unsigned Size) {
return canInstructionRangeModify(I1, I2, Location(Ptr, Size));
}
//===--------------------------------------------------------------------===// //===--------------------------------------------------------------------===//
/// Methods that clients should call when they transform the program to allow /// Methods that clients should call when they transform the program to allow
@@ -401,17 +393,6 @@ public:
copyValue(Old, New); copyValue(Old, New);
deleteValue(Old); deleteValue(Old);
} }
protected:
/// getDependenceViaModRefInfo - Helper function for implementing getDependence
/// in implementations which already have getModRefInfo implementations.
DependenceResult getDependenceViaModRefInfo(const Instruction *First,
const Value *FirstPHITranslatedAddr,
DependenceQueryFlags FirstFlags,
const Instruction *Second,
const Value *SecondPHITranslatedAddr,
DependenceQueryFlags SecondFlags);
}; };
/// isNoAliasCall - Return true if this pointer is returned by a noalias /// isNoAliasCall - Return true if this pointer is returned by a noalias

4
include/llvm/Analysis/LibCallAliasAnalysis.h
View File

@@ -36,7 +36,7 @@ namespace llvm {
~LibCallAliasAnalysis(); ~LibCallAliasAnalysis();
ModRefResult getModRefInfo(ImmutableCallSite CS, ModRefResult getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size); const Location &Loc);
ModRefResult getModRefInfo(ImmutableCallSite CS1, ModRefResult getModRefInfo(ImmutableCallSite CS1,
ImmutableCallSite CS2) { ImmutableCallSite CS2) {
@@ -64,7 +64,7 @@ namespace llvm {
private: private:
ModRefResult AnalyzeLibCallDetails(const LibCallFunctionInfo *FI, ModRefResult AnalyzeLibCallDetails(const LibCallFunctionInfo *FI,
ImmutableCallSite CS, ImmutableCallSite CS,
const Value *P, unsigned Size); const Location &Loc);
}; };
} // End of llvm namespace } // End of llvm namespace

2
include/llvm/Analysis/LibCallSemantics.h
View File

@@ -48,7 +48,7 @@ namespace llvm {
Yes, No, Unknown Yes, No, Unknown
}; };
LocResult (*isLocation)(ImmutableCallSite CS, LocResult (*isLocation)(ImmutableCallSite CS,
const Value *Ptr, unsigned Size); const AliasAnalysis::Location &Loc);
}; };
/// LibCallFunctionInfo - Each record in the array of FunctionInfo structs /// LibCallFunctionInfo - Each record in the array of FunctionInfo structs

3
include/llvm/LLVMContext.h
View File

@@ -37,7 +37,8 @@ public:
// Pinned metadata names, which always have the same value. This is a // Pinned metadata names, which always have the same value. This is a
// compile-time performance optimization, not a correctness optimization. // compile-time performance optimization, not a correctness optimization.
enum { enum {
MD_dbg = 0 // "dbg" MD_dbg = 0, // "dbg"
MD_tbaa = 1 // "tbaa"
}; };
/// getMDKindID - Return a unique non-zero ID for the specified metadata kind. /// getMDKindID - Return a unique non-zero ID for the specified metadata kind.

285
lib/Analysis/AliasAnalysis.cpp
View File

@@ -30,6 +30,7 @@
#include "llvm/Function.h" #include "llvm/Function.h"
#include "llvm/IntrinsicInst.h" #include "llvm/IntrinsicInst.h"
#include "llvm/Instructions.h" #include "llvm/Instructions.h"
#include "llvm/LLVMContext.h"
#include "llvm/Type.h" #include "llvm/Type.h"
#include "llvm/Target/TargetData.h" #include "llvm/Target/TargetData.h"
using namespace llvm; using namespace llvm;
@@ -43,15 +44,14 @@ char AliasAnalysis::ID = 0;
//===----------------------------------------------------------------------===// //===----------------------------------------------------------------------===//
AliasAnalysis::AliasResult AliasAnalysis::AliasResult
AliasAnalysis::alias(const Value *V1, unsigned V1Size, AliasAnalysis::alias(const Location &LocA, const Location &LocB) {
const Value *V2, unsigned V2Size) {
assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!"); assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
return AA->alias(V1, V1Size, V2, V2Size); return AA->alias(LocA, LocB);
} }
bool AliasAnalysis::pointsToConstantMemory(const Value *P) { bool AliasAnalysis::pointsToConstantMemory(const Location &Loc) {
assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!"); assert(AA && "AA didn't call InitializeAliasAnalysis in its run method!");
return AA->pointsToConstantMemory(P); return AA->pointsToConstantMemory(Loc);
} }
void AliasAnalysis::deleteValue(Value *V) { void AliasAnalysis::deleteValue(Value *V) {
@@ -66,7 +66,7 @@ void AliasAnalysis::copyValue(Value *From, Value *To) {
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
AliasAnalysis::getModRefInfo(ImmutableCallSite CS, AliasAnalysis::getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size) { const Location &Loc) {
// Don't assert AA because BasicAA calls us in order to make use of the // Don't assert AA because BasicAA calls us in order to make use of the
// logic here. // logic here.
@@ -81,7 +81,7 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS,
bool doesAlias = false; bool doesAlias = false;
for (ImmutableCallSite::arg_iterator AI = CS.arg_begin(), AE = CS.arg_end(); for (ImmutableCallSite::arg_iterator AI = CS.arg_begin(), AE = CS.arg_end();
AI != AE; ++AI) AI != AE; ++AI)
if (!isNoAlias(*AI, ~0U, P, Size)) { if (!isNoAlias(Location(*AI), Loc)) {
doesAlias = true; doesAlias = true;
break; break;
} }
@@ -90,9 +90,9 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS,
return NoModRef; return NoModRef;
} }
// If P points to a constant memory location, the call definitely could not // If Loc is a constant memory location, the call definitely could not
// modify the memory location. // modify the memory location.
if ((Mask & Mod) && pointsToConstantMemory(P)) if ((Mask & Mod) && pointsToConstantMemory(Loc))
Mask = ModRefResult(Mask & ~Mod); Mask = ModRefResult(Mask & ~Mod);
// If this is BasicAA, don't forward. // If this is BasicAA, don't forward.
@@ -100,7 +100,7 @@ AliasAnalysis::getModRefInfo(ImmutableCallSite CS,
// Otherwise, fall back to the next AA in the chain. But we can merge // Otherwise, fall back to the next AA in the chain. But we can merge
// in any mask we've managed to compute. // in any mask we've managed to compute.
return ModRefResult(AA->getModRefInfo(CS, P, Size) & Mask); return ModRefResult(AA->getModRefInfo(CS, Loc) & Mask);
} }
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
@@ -188,31 +188,22 @@ AliasAnalysis::getModRefBehavior(const Function *F) {
return AA->getModRefBehavior(F); return AA->getModRefBehavior(F);
} }
AliasAnalysis::DependenceResult
AliasAnalysis::getDependence(const Instruction *First,
const Value *FirstPHITranslatedAddr,
DependenceQueryFlags FirstFlags,
const Instruction *Second,
const Value *SecondPHITranslatedAddr,
DependenceQueryFlags SecondFlags) {
assert(AA && "AA didn't call InitializeAliasAnalyais in its run method!");
return AA->getDependence(First, FirstPHITranslatedAddr, FirstFlags,
Second, SecondPHITranslatedAddr, SecondFlags);
}
//===----------------------------------------------------------------------===// //===----------------------------------------------------------------------===//
// AliasAnalysis non-virtual helper method implementation // AliasAnalysis non-virtual helper method implementation
//===----------------------------------------------------------------------===// //===----------------------------------------------------------------------===//
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
AliasAnalysis::getModRefInfo(const LoadInst *L, const Value *P, unsigned Size) { AliasAnalysis::getModRefInfo(const LoadInst *L, const Location &Loc) {
// Be conservative in the face of volatile. // Be conservative in the face of volatile.
if (L->isVolatile()) if (L->isVolatile())
return ModRef; return ModRef;
// If the load address doesn't alias the given address, it doesn't read // If the load address doesn't alias the given address, it doesn't read
// or write the specified memory. // or write the specified memory.
if (!alias(L->getOperand(0), getTypeStoreSize(L->getType()), P, Size)) if (!alias(Location(L->getOperand(0),
getTypeStoreSize(L->getType()),
L->getMetadata(LLVMContext::MD_tbaa)),
Loc))
return NoModRef; return NoModRef;
// Otherwise, a load just reads. // Otherwise, a load just reads.
@@ -220,20 +211,22 @@ AliasAnalysis::getModRefInfo(const LoadInst *L, const Value *P, unsigned Size) {
} }
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
AliasAnalysis::getModRefInfo(const StoreInst *S, const Value *P, unsigned Size) { AliasAnalysis::getModRefInfo(const StoreInst *S, const Location &Loc) {
// Be conservative in the face of volatile. // Be conservative in the face of volatile.
if (S->isVolatile()) if (S->isVolatile())
return ModRef; return ModRef;
// If the store address cannot alias the pointer in question, then the // If the store address cannot alias the pointer in question, then the
// specified memory cannot be modified by the store. // specified memory cannot be modified by the store.
if (!alias(S->getOperand(1), if (!alias(Location(S->getOperand(1),
getTypeStoreSize(S->getOperand(0)->getType()), P, Size)) getTypeStoreSize(S->getOperand(0)->getType()),
S->getMetadata(LLVMContext::MD_tbaa)),
Loc))
return NoModRef; return NoModRef;
// If the pointer is a pointer to constant memory, then it could not have been // If the pointer is a pointer to constant memory, then it could not have been
// modified by this store. // modified by this store.
if (pointsToConstantMemory(P)) if (pointsToConstantMemory(Loc))
return NoModRef; return NoModRef;
// Otherwise, a store just writes. // Otherwise, a store just writes.
@@ -241,240 +234,24 @@ AliasAnalysis::getModRefInfo(const StoreInst *S, const Value *P, unsigned Size)
} }
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
AliasAnalysis::getModRefInfo(const VAArgInst *V, const Value *P, unsigned Size) { AliasAnalysis::getModRefInfo(const VAArgInst *V, const Location &Loc) {
// If the va_arg address cannot alias the pointer in question, then the // If the va_arg address cannot alias the pointer in question, then the
// specified memory cannot be accessed by the va_arg. // specified memory cannot be accessed by the va_arg.
if (!alias(V->getOperand(0), UnknownSize, P, Size)) if (!alias(Location(V->getOperand(0),
UnknownSize,
V->getMetadata(LLVMContext::MD_tbaa)),
Loc))
return NoModRef; return NoModRef;
// If the pointer is a pointer to constant memory, then it could not have been // If the pointer is a pointer to constant memory, then it could not have been
// modified by this va_arg. // modified by this va_arg.
if (pointsToConstantMemory(P)) if (pointsToConstantMemory(Loc))
return NoModRef; return NoModRef;
// Otherwise, a va_arg reads and writes. // Otherwise, a va_arg reads and writes.
return ModRef; return ModRef;
} }
AliasAnalysis::DependenceResult
AliasAnalysis::getDependenceViaModRefInfo(const Instruction *First,
const Value *FirstPHITranslatedAddr,
DependenceQueryFlags FirstFlags,
const Instruction *Second,
const Value *SecondPHITranslatedAddr,
DependenceQueryFlags SecondFlags) {
if (const LoadInst *L = dyn_cast<LoadInst>(First)) {
// Be over-conservative with volatile for now.
if (L->isVolatile())
return Unknown;
// If we don't have a phi-translated address, use the actual one.
if (!FirstPHITranslatedAddr)
FirstPHITranslatedAddr = L->getPointerOperand();
// Forward this query to getModRefInfo.
switch (getModRefInfo(Second,
FirstPHITranslatedAddr,
getTypeStoreSize(L->getType()))) {
case NoModRef:
// Second doesn't reference First's memory, so they're independent.
return Independent;
case Ref:
// Second only reads from the memory read from by First. If it
// also writes to any other memory, be conservative.
if (Second->mayWriteToMemory())
return Unknown;
// If it's loading the same size from the same address, we can
// give a more precise result.
if (const LoadInst *SecondL = dyn_cast<LoadInst>(Second)) {
// If we don't have a phi-translated address, use the actual one.
if (!SecondPHITranslatedAddr)
SecondPHITranslatedAddr = SecondL->getPointerOperand();
unsigned LSize = getTypeStoreSize(L->getType());
unsigned SecondLSize = getTypeStoreSize(SecondL->getType());
if (alias(FirstPHITranslatedAddr, LSize,
SecondPHITranslatedAddr, SecondLSize) ==
MustAlias) {
// If the loads are the same size, it's ReadThenRead.
if (LSize == SecondLSize)
return ReadThenRead;
// If the second load is smaller, it's only ReadThenReadSome.
if (LSize > SecondLSize)
return ReadThenReadSome;
}
}
// Otherwise it's just two loads.
return Independent;
case Mod:
// Second only writes to the memory read from by First. If it
// also reads from any other memory, be conservative.
if (Second->mayReadFromMemory())
return Unknown;
// If it's storing the same size to the same address, we can
// give a more precise result.
if (const StoreInst *SecondS = dyn_cast<StoreInst>(Second)) {
// If we don't have a phi-translated address, use the actual one.
if (!SecondPHITranslatedAddr)
SecondPHITranslatedAddr = SecondS->getPointerOperand();
unsigned LSize = getTypeStoreSize(L->getType());
unsigned SecondSSize = getTypeStoreSize(SecondS->getType());
if (alias(FirstPHITranslatedAddr, LSize,
SecondPHITranslatedAddr, SecondSSize) ==
MustAlias) {
// If the load and the store are the same size, it's ReadThenWrite.
if (LSize == SecondSSize)
return ReadThenWrite;
}
}
// Otherwise we don't know if it could be writing to other memory.
return Unknown;
case ModRef:
// Second reads and writes to the memory read from by First.
// We don't have a way to express that.
return Unknown;
}
} else if (const StoreInst *S = dyn_cast<StoreInst>(First)) {
// Be over-conservative with volatile for now.
if (S->isVolatile())
return Unknown;
// If we don't have a phi-translated address, use the actual one.
if (!FirstPHITranslatedAddr)
FirstPHITranslatedAddr = S->getPointerOperand();
// Forward this query to getModRefInfo.
switch (getModRefInfo(Second,
FirstPHITranslatedAddr,
getTypeStoreSize(S->getValueOperand()->getType()))) {
case NoModRef:
// Second doesn't reference First's memory, so they're independent.
return Independent;
case Ref:
// Second only reads from the memory written to by First. If it
// also writes to any other memory, be conservative.
if (Second->mayWriteToMemory())
return Unknown;
// If it's loading the same size from the same address, we can
// give a more precise result.
if (const LoadInst *SecondL = dyn_cast<LoadInst>(Second)) {
// If we don't have a phi-translated address, use the actual one.
if (!SecondPHITranslatedAddr)
SecondPHITranslatedAddr = SecondL->getPointerOperand();
unsigned SSize = getTypeStoreSize(S->getValueOperand()->getType());
unsigned SecondLSize = getTypeStoreSize(SecondL->getType());
if (alias(FirstPHITranslatedAddr, SSize,
SecondPHITranslatedAddr, SecondLSize) ==
MustAlias) {
// If the store and the load are the same size, it's WriteThenRead.
if (SSize == SecondLSize)
return WriteThenRead;
// If the load is smaller, it's only WriteThenReadSome.
if (SSize > SecondLSize)
return WriteThenReadSome;
}
}
// Otherwise we don't know if it could be reading from other memory.
return Unknown;
case Mod:
// Second only writes to the memory written to by First. If it
// also reads from any other memory, be conservative.
if (Second->mayReadFromMemory())
return Unknown;
// If it's storing the same size to the same address, we can
// give a more precise result.
if (const StoreInst *SecondS = dyn_cast<StoreInst>(Second)) {
// If we don't have a phi-translated address, use the actual one.
if (!SecondPHITranslatedAddr)
SecondPHITranslatedAddr = SecondS->getPointerOperand();
unsigned SSize = getTypeStoreSize(S->getValueOperand()->getType());
unsigned SecondSSize = getTypeStoreSize(SecondS->getType());
if (alias(FirstPHITranslatedAddr, SSize,
SecondPHITranslatedAddr, SecondSSize) ==
MustAlias) {
// If the stores are the same size, it's WriteThenWrite.
if (SSize == SecondSSize)
return WriteThenWrite;
// If the second store is larger, it's only WriteSomeThenWrite.
if (SSize < SecondSSize)
return WriteSomeThenWrite;
}
}
// Otherwise we don't know if it could be writing to other memory.
return Unknown;
case ModRef:
// Second reads and writes to the memory written to by First.
// We don't have a way to express that.
return Unknown;
}
} else if (const VAArgInst *V = dyn_cast<VAArgInst>(First)) {
// If we don't have a phi-translated address, use the actual one.
if (!FirstPHITranslatedAddr)
FirstPHITranslatedAddr = V->getPointerOperand();
// Forward this query to getModRefInfo.
if (getModRefInfo(Second, FirstPHITranslatedAddr, UnknownSize) == NoModRef)
// Second doesn't reference First's memory, so they're independent.
return Independent;
} else if (ImmutableCallSite FirstCS = cast<Value>(First)) {
assert(!FirstPHITranslatedAddr &&
!SecondPHITranslatedAddr &&
"PHI translation with calls not supported yet!");
// If both instructions are calls/invokes we can use the two-callsite
// form of getModRefInfo.
if (ImmutableCallSite SecondCS = cast<Value>(Second))
// getModRefInfo's arguments are backwards from intuition.
switch (getModRefInfo(SecondCS, FirstCS)) {
case NoModRef:
// Second doesn't reference First's memory, so they're independent.
return Independent;
case Ref:
// If they're both read-only, there's no dependence.
if (FirstCS.onlyReadsMemory() && SecondCS.onlyReadsMemory())
return Independent;
// Otherwise it's not obvious what we can do here.
return Unknown;
case Mod:
// It's not obvious what we can do here.
return Unknown;
case ModRef:
// I know, right?
return Unknown;
}
}
// For anything else, be conservative.
return Unknown;
}
AliasAnalysis::ModRefBehavior AliasAnalysis::ModRefBehavior
AliasAnalysis::getIntrinsicModRefBehavior(unsigned iid) { AliasAnalysis::getIntrinsicModRefBehavior(unsigned iid) {
#define GET_INTRINSIC_MODREF_BEHAVIOR #define GET_INTRINSIC_MODREF_BEHAVIOR
@@ -514,8 +291,8 @@ unsigned AliasAnalysis::getTypeStoreSize(const Type *Ty) {
/// specified basic block to modify the value pointed to by Ptr. /// specified basic block to modify the value pointed to by Ptr.
/// ///
bool AliasAnalysis::canBasicBlockModify(const BasicBlock &BB, bool AliasAnalysis::canBasicBlockModify(const BasicBlock &BB,
const Value *Ptr, unsigned Size) { const Location &Loc) {
return canInstructionRangeModify(BB.front(), BB.back(), Ptr, Size); return canInstructionRangeModify(BB.front(), BB.back(), Loc);
} }
/// canInstructionRangeModify - Return true if it is possible for the execution /// canInstructionRangeModify - Return true if it is possible for the execution
@@ -525,7 +302,7 @@ bool AliasAnalysis::canBasicBlockModify(const BasicBlock &BB,
/// ///
bool AliasAnalysis::canInstructionRangeModify(const Instruction &I1, bool AliasAnalysis::canInstructionRangeModify(const Instruction &I1,
const Instruction &I2, const Instruction &I2,
const Value *Ptr, unsigned Size) { const Location &Loc) {
assert(I1.getParent() == I2.getParent() && assert(I1.getParent() == I2.getParent() &&
"Instructions not in same basic block!"); "Instructions not in same basic block!");
BasicBlock::const_iterator I = &I1; BasicBlock::const_iterator I = &I1;
@@ -533,7 +310,7 @@ bool AliasAnalysis::canInstructionRangeModify(const Instruction &I1,
++E; // Convert from inclusive to exclusive range. ++E; // Convert from inclusive to exclusive range.
for (; I != E; ++I) // Check every instruction in range for (; I != E; ++I) // Check every instruction in range
if (getModRefInfo(I, Ptr, Size) & Mod) if (getModRefInfo(I, Loc) & Mod)
return true; return true;
return false; return false;
} }

30
lib/Analysis/AliasAnalysisCounter.cpp
View File

@@ -94,17 +94,16 @@ namespace {
} }
// FIXME: We could count these too... // FIXME: We could count these too...
bool pointsToConstantMemory(const Value *P) { bool pointsToConstantMemory(const Location &Loc) {
return getAnalysis<AliasAnalysis>().pointsToConstantMemory(P); return getAnalysis<AliasAnalysis>().pointsToConstantMemory(Loc);
} }
// Forwarding functions: just delegate to a real AA implementation, counting // Forwarding functions: just delegate to a real AA implementation, counting
// the number of responses... // the number of responses...
AliasResult alias(const Value *V1, unsigned V1Size, AliasResult alias(const Location &LocA, const Location &LocB);
const Value *V2, unsigned V2Size);
ModRefResult getModRefInfo(ImmutableCallSite CS, ModRefResult getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size); const Location &Loc);
ModRefResult getModRefInfo(ImmutableCallSite CS1, ModRefResult getModRefInfo(ImmutableCallSite CS1,
ImmutableCallSite CS2) { ImmutableCallSite CS2) {
return AliasAnalysis::getModRefInfo(CS1,CS2); return AliasAnalysis::getModRefInfo(CS1,CS2);
@@ -121,9 +120,8 @@ ModulePass *llvm::createAliasAnalysisCounterPass() {
} }
AliasAnalysis::AliasResult AliasAnalysis::AliasResult
AliasAnalysisCounter::alias(const Value *V1, unsigned V1Size, AliasAnalysisCounter::alias(const Location &LocA, const Location &LocB) {
const Value *V2, unsigned V2Size) { AliasResult R = getAnalysis<AliasAnalysis>().alias(LocA, LocB);
AliasResult R = getAnalysis<AliasAnalysis>().alias(V1, V1Size, V2, V2Size);
const char *AliasString; const char *AliasString;
switch (R) { switch (R) {
@@ -135,11 +133,11 @@ AliasAnalysisCounter::alias(const Value *V1, unsigned V1Size,
if (PrintAll || (PrintAllFailures && R == MayAlias)) { if (PrintAll || (PrintAllFailures && R == MayAlias)) {
errs() << AliasString << ":\t"; errs() << AliasString << ":\t";
errs() << "[" << V1Size << "B] "; errs() << "[" << LocA.Size << "B] ";
WriteAsOperand(errs(), V1, true, M); WriteAsOperand(errs(), LocA.Ptr, true, M);
errs() << ", "; errs() << ", ";
errs() << "[" << V2Size << "B] "; errs() << "[" << LocB.Size << "B] ";
WriteAsOperand(errs(), V2, true, M); WriteAsOperand(errs(), LocB.Ptr, true, M);
errs() << "\n"; errs() << "\n";
} }
@@ -148,8 +146,8 @@ AliasAnalysisCounter::alias(const Value *V1, unsigned V1Size,
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
AliasAnalysisCounter::getModRefInfo(ImmutableCallSite CS, AliasAnalysisCounter::getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size) { const Location &Loc) {
ModRefResult R = getAnalysis<AliasAnalysis>().getModRefInfo(CS, P, Size); ModRefResult R = getAnalysis<AliasAnalysis>().getModRefInfo(CS, Loc);
const char *MRString; const char *MRString;
switch (R) { switch (R) {
@@ -162,8 +160,8 @@ AliasAnalysisCounter::getModRefInfo(ImmutableCallSite CS,
if (PrintAll || (PrintAllFailures && R == ModRef)) { if (PrintAll || (PrintAllFailures && R == ModRef)) {
errs() << MRString << ": Ptr: "; errs() << MRString << ": Ptr: ";
errs() << "[" << Size << "B] "; errs() << "[" << Loc.Size << "B] ";
WriteAsOperand(errs(), P, true, M); WriteAsOperand(errs(), Loc.Ptr, true, M);
errs() << "\t<->" << *CS.getInstruction() << '\n'; errs() << "\t<->" << *CS.getInstruction() << '\n';
} }
return R; return R;

23
lib/Analysis/AliasDebugger.cpp
View File

@@ -92,17 +92,18 @@ namespace {
//------------------------------------------------ //------------------------------------------------
// Implement the AliasAnalysis API // Implement the AliasAnalysis API
// //
AliasResult alias(const Value *V1, unsigned V1Size, AliasResult alias(const Location &LocA, const Location &LocB) {
const Value *V2, unsigned V2Size) { assert(Vals.find(LocA.Ptr) != Vals.end() &&
assert(Vals.find(V1) != Vals.end() && "Never seen value in AA before"); "Never seen value in AA before");
assert(Vals.find(V2) != Vals.end() && "Never seen value in AA before"); assert(Vals.find(LocB.Ptr) != Vals.end() &&
return AliasAnalysis::alias(V1, V1Size, V2, V2Size); "Never seen value in AA before");
return AliasAnalysis::alias(LocA, LocB);
} }
ModRefResult getModRefInfo(ImmutableCallSite CS, ModRefResult getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size) { const Location &Loc) {
assert(Vals.find(P) != Vals.end() && "Never seen value in AA before"); assert(Vals.find(Loc.Ptr) != Vals.end() && "Never seen value in AA before");
return AliasAnalysis::getModRefInfo(CS, P, Size); return AliasAnalysis::getModRefInfo(CS, Loc);
} }
ModRefResult getModRefInfo(ImmutableCallSite CS1, ModRefResult getModRefInfo(ImmutableCallSite CS1,
@@ -110,9 +111,9 @@ namespace {
return AliasAnalysis::getModRefInfo(CS1,CS2); return AliasAnalysis::getModRefInfo(CS1,CS2);
} }
bool pointsToConstantMemory(const Value *P) { bool pointsToConstantMemory(const Location &Loc) {
assert(Vals.find(P) != Vals.end() && "Never seen value in AA before"); assert(Vals.find(Loc.Ptr) != Vals.end() && "Never seen value in AA before");
return AliasAnalysis::pointsToConstantMemory(P); return AliasAnalysis::pointsToConstantMemory(Loc);
} }
virtual void deleteValue(Value *V) { virtual void deleteValue(Value *V) {

89
lib/Analysis/BasicAliasAnalysis.cpp
View File

@@ -22,6 +22,7 @@
#include "llvm/GlobalVariable.h" #include "llvm/GlobalVariable.h"
#include "llvm/Instructions.h" #include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h" #include "llvm/IntrinsicInst.h"
#include "llvm/LLVMContext.h"
#include "llvm/Operator.h" #include "llvm/Operator.h"
#include "llvm/Pass.h" #include "llvm/Pass.h"
#include "llvm/Analysis/CaptureTracking.h" #include "llvm/Analysis/CaptureTracking.h"
@@ -149,8 +150,7 @@ namespace {
TD = getAnalysisIfAvailable<TargetData>(); TD = getAnalysisIfAvailable<TargetData>();
} }
virtual AliasResult alias(const Value *V1, unsigned V1Size, virtual AliasResult alias(const Location &LocA, const Location &LocB) {
const Value *V2, unsigned V2Size) {
return MayAlias; return MayAlias;
} }
@@ -161,9 +161,9 @@ namespace {
return UnknownModRefBehavior; return UnknownModRefBehavior;
} }
virtual bool pointsToConstantMemory(const Value *P) { return false; } virtual bool pointsToConstantMemory(const Location &Loc) { return false; }
virtual ModRefResult getModRefInfo(ImmutableCallSite CS, virtual ModRefResult getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size) { const Location &Loc) {
return ModRef; return ModRef;
} }
virtual ModRefResult getModRefInfo(ImmutableCallSite CS1, virtual ModRefResult getModRefInfo(ImmutableCallSite CS1,
@@ -171,15 +171,6 @@ namespace {
return ModRef; return ModRef;
} }
virtual DependenceResult getDependence(const Instruction *First,
const Value *FirstPHITranslatedAddr,
DependenceQueryFlags FirstFlags,
const Instruction *Second,
const Value *SecondPHITranslatedAddr,
DependenceQueryFlags SecondFlags) {
return Unknown;
}
virtual void deleteValue(Value *V) {} virtual void deleteValue(Value *V) {}
virtual void copyValue(Value *From, Value *To) {} virtual void copyValue(Value *From, Value *To) {}
@@ -501,18 +492,18 @@ namespace {
static char ID; // Class identification, replacement for typeinfo static char ID; // Class identification, replacement for typeinfo
BasicAliasAnalysis() : NoAA(ID) {} BasicAliasAnalysis() : NoAA(ID) {}
virtual AliasResult alias(const Value *V1, unsigned V1Size, virtual AliasResult alias(const Location &LocA,
const Value *V2, unsigned V2Size) { const Location &LocB) {
assert(Visited.empty() && "Visited must be cleared after use!"); assert(Visited.empty() && "Visited must be cleared after use!");
assert(notDifferentParent(V1, V2) && assert(notDifferentParent(LocA.Ptr, LocB.Ptr) &&
"BasicAliasAnalysis doesn't support interprocedural queries."); "BasicAliasAnalysis doesn't support interprocedural queries.");
AliasResult Alias = aliasCheck(V1, V1Size, V2, V2Size); AliasResult Alias = aliasCheck(LocA.Ptr, LocA.Size, LocB.Ptr, LocB.Size);
Visited.clear(); Visited.clear();
return Alias; return Alias;
} }
virtual ModRefResult getModRefInfo(ImmutableCallSite CS, virtual ModRefResult getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size); const Location &Loc);
virtual ModRefResult getModRefInfo(ImmutableCallSite CS1, virtual ModRefResult getModRefInfo(ImmutableCallSite CS1,
ImmutableCallSite CS2) { ImmutableCallSite CS2) {
@@ -522,7 +513,7 @@ namespace {
/// pointsToConstantMemory - Chase pointers until we find a (constant /// pointsToConstantMemory - Chase pointers until we find a (constant
/// global) or not. /// global) or not.
virtual bool pointsToConstantMemory(const Value *P); virtual bool pointsToConstantMemory(const Location &Loc);
/// getModRefBehavior - Return the behavior when calling the given /// getModRefBehavior - Return the behavior when calling the given
/// call site. /// call site.
@@ -532,13 +523,6 @@ namespace {
/// For use when the call site is not known. /// For use when the call site is not known.
virtual ModRefBehavior getModRefBehavior(const Function *F); virtual ModRefBehavior getModRefBehavior(const Function *F);
virtual DependenceResult getDependence(const Instruction *First,
const Value *FirstPHITranslatedAddr,
DependenceQueryFlags FirstFlags,
const Instruction *Second,
const Value *SecondPHITranslatedAddr,
DependenceQueryFlags SecondFlags);
/// getAdjustedAnalysisPointer - This method is used when a pass implements /// getAdjustedAnalysisPointer - This method is used when a pass implements
/// an analysis interface through multiple inheritance. If needed, it /// an analysis interface through multiple inheritance. If needed, it
/// should override this to adjust the this pointer as needed for the /// should override this to adjust the this pointer as needed for the
@@ -586,15 +570,15 @@ ImmutablePass *llvm::createBasicAliasAnalysisPass() {
/// pointsToConstantMemory - Chase pointers until we find a (constant /// pointsToConstantMemory - Chase pointers until we find a (constant
/// global) or not. /// global) or not.
bool BasicAliasAnalysis::pointsToConstantMemory(const Value *P) { bool BasicAliasAnalysis::pointsToConstantMemory(const Location &Loc) {
if (const GlobalVariable *GV = if (const GlobalVariable *GV =
dyn_cast<GlobalVariable>(P->getUnderlyingObject())) dyn_cast<GlobalVariable>(Loc.Ptr->getUnderlyingObject()))
// Note: this doesn't require GV to be "ODR" because it isn't legal for a // Note: this doesn't require GV to be "ODR" because it isn't legal for a
// global to be marked constant in some modules and non-constant in others. // global to be marked constant in some modules and non-constant in others.
// GV may even be a declaration, not a definition. // GV may even be a declaration, not a definition.
return GV->isConstant(); return GV->isConstant();
return NoAA::pointsToConstantMemory(P); return NoAA::pointsToConstantMemory(Loc);
} }
/// getModRefBehavior - Return the behavior when calling the given call site. /// getModRefBehavior - Return the behavior when calling the given call site.
@@ -636,13 +620,13 @@ BasicAliasAnalysis::getModRefBehavior(const Function *F) {
/// simple "address taken" analysis on local objects. /// simple "address taken" analysis on local objects.
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS, BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size) { const Location &Loc) {
assert(notDifferentParent(CS.getInstruction(), P) && assert(notDifferentParent(CS.getInstruction(), Loc.Ptr) &&
"AliasAnalysis query involving multiple functions!"); "AliasAnalysis query involving multiple functions!");
const Value *Object = P->getUnderlyingObject(); const Value *Object = Loc.Ptr->getUnderlyingObject();
// If this is a tail call and P points to a stack location, we know that // If this is a tail call and Loc.Ptr points to a stack location, we know that
// the tail call cannot access or modify the local stack. // the tail call cannot access or modify the local stack.
// We cannot exclude byval arguments here; these belong to the caller of // We cannot exclude byval arguments here; these belong to the caller of
// the current function not to the current function, and a tail callee // the current function not to the current function, and a tail callee
@@ -666,11 +650,11 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
!CS.paramHasAttr(ArgNo+1, Attribute::NoCapture)) !CS.paramHasAttr(ArgNo+1, Attribute::NoCapture))
continue; continue;
// If this is a no-capture pointer argument, see if we can tell that it // If this is a no-capture pointer argument, see if we can tell that it
// is impossible to alias the pointer we're checking. If not, we have to // is impossible to alias the pointer we're checking. If not, we have to
// assume that the call could touch the pointer, even though it doesn't // assume that the call could touch the pointer, even though it doesn't
// escape. // escape.
if (!isNoAlias(cast<Value>(CI), UnknownSize, P, UnknownSize)) { if (!isNoAlias(Location(cast<Value>(CI)), Loc)) {
PassedAsArg = true; PassedAsArg = true;
break; break;
} }
@@ -692,8 +676,8 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
Len = LenCI->getZExtValue(); Len = LenCI->getZExtValue();
Value *Dest = II->getArgOperand(0); Value *Dest = II->getArgOperand(0);
Value *Src = II->getArgOperand(1); Value *Src = II->getArgOperand(1);
if (isNoAlias(Dest, Len, P, Size)) { if (isNoAlias(Location(Dest, Len), Loc)) {
if (isNoAlias(Src, Len, P, Size)) if (isNoAlias(Location(Src, Len), Loc))
return NoModRef; return NoModRef;
return Ref; return Ref;
} }
@@ -705,7 +689,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
if (ConstantInt *LenCI = dyn_cast<ConstantInt>(II->getArgOperand(2))) { if (ConstantInt *LenCI = dyn_cast<ConstantInt>(II->getArgOperand(2))) {
unsigned Len = LenCI->getZExtValue(); unsigned Len = LenCI->getZExtValue();
Value *Dest = II->getArgOperand(0); Value *Dest = II->getArgOperand(0);
if (isNoAlias(Dest, Len, P, Size)) if (isNoAlias(Location(Dest, Len), Loc))
return NoModRef; return NoModRef;
} }
break; break;
@@ -724,7 +708,8 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
if (TD) { if (TD) {
Value *Op1 = II->getArgOperand(0); Value *Op1 = II->getArgOperand(0);
unsigned Op1Size = TD->getTypeStoreSize(Op1->getType()); unsigned Op1Size = TD->getTypeStoreSize(Op1->getType());
if (isNoAlias(Op1, Op1Size, P, Size)) MDNode *Tag = II->getMetadata(LLVMContext::MD_tbaa);
if (isNoAlias(Location(Op1, Op1Size, Tag), Loc))
return NoModRef; return NoModRef;
} }
break; break;
@@ -733,33 +718,27 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
case Intrinsic::invariant_start: { case Intrinsic::invariant_start: {
unsigned PtrSize = unsigned PtrSize =
cast<ConstantInt>(II->getArgOperand(0))->getZExtValue(); cast<ConstantInt>(II->getArgOperand(0))->getZExtValue();
if (isNoAlias(II->getArgOperand(1), PtrSize, P, Size)) if (isNoAlias(Location(II->getArgOperand(1),
PtrSize,
II->getMetadata(LLVMContext::MD_tbaa)),
Loc))
return NoModRef; return NoModRef;
break; break;
} }
case Intrinsic::invariant_end: { case Intrinsic::invariant_end: {
unsigned PtrSize = unsigned PtrSize =
cast<ConstantInt>(II->getArgOperand(1))->getZExtValue(); cast<ConstantInt>(II->getArgOperand(1))->getZExtValue();
if (isNoAlias(II->getArgOperand(2), PtrSize, P, Size)) if (isNoAlias(Location(II->getArgOperand(2),
PtrSize,
II->getMetadata(LLVMContext::MD_tbaa)),
Loc))
return NoModRef; return NoModRef;
break; break;
} }
} }
// The AliasAnalysis base class has some smarts, lets use them. // The AliasAnalysis base class has some smarts, lets use them.
return AliasAnalysis::getModRefInfo(CS, P, Size); return AliasAnalysis::getModRefInfo(CS, Loc);
}
AliasAnalysis::DependenceResult
BasicAliasAnalysis::getDependence(const Instruction *First,
const Value *FirstPHITranslatedAddr,
DependenceQueryFlags FirstFlags,
const Instruction *Second,
const Value *SecondPHITranslatedAddr,
DependenceQueryFlags SecondFlags) {
// We don't have anything special to say yet.
return getDependenceViaModRefInfo(First, FirstPHITranslatedAddr, FirstFlags,
Second, SecondPHITranslatedAddr, SecondFlags);
} }
/// aliasGEP - Provide a bunch of ad-hoc rules to disambiguate a GEP instruction /// aliasGEP - Provide a bunch of ad-hoc rules to disambiguate a GEP instruction
@@ -1103,7 +1082,7 @@ BasicAliasAnalysis::aliasCheck(const Value *V1, unsigned V1Size,
if (const SelectInst *S1 = dyn_cast<SelectInst>(V1)) if (const SelectInst *S1 = dyn_cast<SelectInst>(V1))
return aliasSelect(S1, V1Size, V2, V2Size); return aliasSelect(S1, V1Size, V2, V2Size);
return NoAA::alias(V1, V1Size, V2, V2Size); return NoAA::alias(Location(V1, V1Size), Location(V2, V2Size));
} }
// Make sure that anything that uses AliasAnalysis pulls in this file. // Make sure that anything that uses AliasAnalysis pulls in this file.

22
lib/Analysis/IPA/GlobalsModRef.cpp
View File

@@ -106,10 +106,9 @@ namespace {
//------------------------------------------------ //------------------------------------------------
// Implement the AliasAnalysis API // Implement the AliasAnalysis API
// //
AliasResult alias(const Value *V1, unsigned V1Size, AliasResult alias(const Location &LocA, const Location &LocB);
const Value *V2, unsigned V2Size);
ModRefResult getModRefInfo(ImmutableCallSite CS, ModRefResult getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size); const Location &Loc);
ModRefResult getModRefInfo(ImmutableCallSite CS1, ModRefResult getModRefInfo(ImmutableCallSite CS1,
ImmutableCallSite CS2) { ImmutableCallSite CS2) {
return AliasAnalysis::getModRefInfo(CS1, CS2); return AliasAnalysis::getModRefInfo(CS1, CS2);
@@ -476,11 +475,11 @@ void GlobalsModRef::AnalyzeCallGraph(CallGraph &CG, Module &M) {
/// other is some random pointer, we know there cannot be an alias, because the /// other is some random pointer, we know there cannot be an alias, because the
/// address of the global isn't taken. /// address of the global isn't taken.
AliasAnalysis::AliasResult AliasAnalysis::AliasResult
GlobalsModRef::alias(const Value *V1, unsigned V1Size, GlobalsModRef::alias(const Location &LocA,
const Value *V2, unsigned V2Size) { const Location &LocB) {
// Get the base object these pointers point to. // Get the base object these pointers point to.
const Value *UV1 = V1->getUnderlyingObject(); const Value *UV1 = LocA.Ptr->getUnderlyingObject();
const Value *UV2 = V2->getUnderlyingObject(); const Value *UV2 = LocB.Ptr->getUnderlyingObject();
// If either of the underlying values is a global, they may be non-addr-taken // If either of the underlying values is a global, they may be non-addr-taken
// globals, which we can answer queries about. // globals, which we can answer queries about.
@@ -528,17 +527,18 @@ GlobalsModRef::alias(const Value *V1, unsigned V1Size,
if ((GV1 || GV2) && GV1 != GV2) if ((GV1 || GV2) && GV1 != GV2)
return NoAlias; return NoAlias;
return AliasAnalysis::alias(V1, V1Size, V2, V2Size); return AliasAnalysis::alias(LocA, LocB);
} }
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
GlobalsModRef::getModRefInfo(ImmutableCallSite CS, GlobalsModRef::getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size) { const Location &Loc) {
unsigned Known = ModRef; unsigned Known = ModRef;
// If we are asking for mod/ref info of a direct call with a pointer to a // If we are asking for mod/ref info of a direct call with a pointer to a
// global we are tracking, return information if we have it. // global we are tracking, return information if we have it.
if (const GlobalValue *GV = dyn_cast<GlobalValue>(P->getUnderlyingObject())) if (const GlobalValue *GV =
dyn_cast<GlobalValue>(Loc.Ptr->getUnderlyingObject()))
if (GV->hasLocalLinkage()) if (GV->hasLocalLinkage())
if (const Function *F = CS.getCalledFunction()) if (const Function *F = CS.getCalledFunction())
if (NonAddressTakenGlobals.count(GV)) if (NonAddressTakenGlobals.count(GV))
@@ -547,7 +547,7 @@ GlobalsModRef::getModRefInfo(ImmutableCallSite CS,
if (Known == NoModRef) if (Known == NoModRef)
return NoModRef; // No need to query other mod/ref analyses return NoModRef; // No need to query other mod/ref analyses
return ModRefResult(Known & AliasAnalysis::getModRefInfo(CS, P, Size)); return ModRefResult(Known & AliasAnalysis::getModRefInfo(CS, Loc));
} }

18
lib/Analysis/LibCallAliasAnalysis.cpp
View File

@@ -43,8 +43,8 @@ void LibCallAliasAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
/// vs the specified pointer/size. /// vs the specified pointer/size.
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
LibCallAliasAnalysis::AnalyzeLibCallDetails(const LibCallFunctionInfo *FI, LibCallAliasAnalysis::AnalyzeLibCallDetails(const LibCallFunctionInfo *FI,
ImmutableCallSite CS, const Value *P, ImmutableCallSite CS,
unsigned Size) { const Location &Loc) {
// If we have a function, check to see what kind of mod/ref effects it // If we have a function, check to see what kind of mod/ref effects it
// has. Start by including any info globally known about the function. // has. Start by including any info globally known about the function.
AliasAnalysis::ModRefResult MRInfo = FI->UniversalBehavior; AliasAnalysis::ModRefResult MRInfo = FI->UniversalBehavior;
@@ -64,9 +64,9 @@ LibCallAliasAnalysis::AnalyzeLibCallDetails(const LibCallFunctionInfo *FI,
if (FI->DetailsType == LibCallFunctionInfo::DoesNot) { if (FI->DetailsType == LibCallFunctionInfo::DoesNot) {
// Find out if the pointer refers to a known location. // Find out if the pointer refers to a known location.
for (unsigned i = 0; Details[i].LocationID != ~0U; ++i) { for (unsigned i = 0; Details[i].LocationID != ~0U; ++i) {
const LibCallLocationInfo &Loc = const LibCallLocationInfo &LocInfo =
LCI->getLocationInfo(Details[i].LocationID); LCI->getLocationInfo(Details[i].LocationID);
LibCallLocationInfo::LocResult Res = Loc.isLocation(CS, P, Size); LibCallLocationInfo::LocResult Res = LocInfo.isLocation(CS, Loc);
if (Res != LibCallLocationInfo::Yes) continue; if (Res != LibCallLocationInfo::Yes) continue;
// If we find a match against a location that we 'do not' interact with, // If we find a match against a location that we 'do not' interact with,
@@ -85,9 +85,9 @@ LibCallAliasAnalysis::AnalyzeLibCallDetails(const LibCallFunctionInfo *FI,
// Find out if the pointer refers to a known location. // Find out if the pointer refers to a known location.
bool NoneMatch = true; bool NoneMatch = true;
for (unsigned i = 0; Details[i].LocationID != ~0U; ++i) { for (unsigned i = 0; Details[i].LocationID != ~0U; ++i) {
const LibCallLocationInfo &Loc = const LibCallLocationInfo &LocInfo =
LCI->getLocationInfo(Details[i].LocationID); LCI->getLocationInfo(Details[i].LocationID);
LibCallLocationInfo::LocResult Res = Loc.isLocation(CS, P, Size); LibCallLocationInfo::LocResult Res = LocInfo.isLocation(CS, Loc);
if (Res == LibCallLocationInfo::No) continue; if (Res == LibCallLocationInfo::No) continue;
// If we don't know if this pointer points to the location, then we have to // If we don't know if this pointer points to the location, then we have to
@@ -118,7 +118,7 @@ LibCallAliasAnalysis::AnalyzeLibCallDetails(const LibCallFunctionInfo *FI,
// //
AliasAnalysis::ModRefResult AliasAnalysis::ModRefResult
LibCallAliasAnalysis::getModRefInfo(ImmutableCallSite CS, LibCallAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
const Value *P, unsigned Size) { const Location &Loc) {
ModRefResult MRInfo = ModRef; ModRefResult MRInfo = ModRef;
// If this is a direct call to a function that LCI knows about, get the // If this is a direct call to a function that LCI knows about, get the
@@ -126,12 +126,12 @@ LibCallAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
if (LCI) { if (LCI) {
if (const Function *F = CS.getCalledFunction()) { if (const Function *F = CS.getCalledFunction()) {
if (const LibCallFunctionInfo *FI = LCI->getFunctionInfo(F)) { if (const LibCallFunctionInfo *FI = LCI->getFunctionInfo(F)) {
MRInfo = ModRefResult(MRInfo & AnalyzeLibCallDetails(FI, CS, P, Size)); MRInfo = ModRefResult(MRInfo & AnalyzeLibCallDetails(FI, CS, Loc));
if (MRInfo == NoModRef) return NoModRef; if (MRInfo == NoModRef) return NoModRef;
} }
} }
} }
// The AliasAnalysis base class has some smarts, lets use them. // The AliasAnalysis base class has some smarts, lets use them.
return (ModRefResult)(MRInfo | AliasAnalysis::getModRefInfo(CS, P, Size)); return (ModRefResult)(MRInfo | AliasAnalysis::getModRefInfo(CS, Loc));
} }

29
lib/Analysis/ScalarEvolutionAliasAnalysis.cpp
View File

@@ -49,8 +49,7 @@ namespace {
private: private:
virtual void getAnalysisUsage(AnalysisUsage &AU) const; virtual void getAnalysisUsage(AnalysisUsage &AU) const;
virtual bool runOnFunction(Function &F); virtual bool runOnFunction(Function &F);
virtual AliasResult alias(const Value *V1, unsigned V1Size, virtual AliasResult alias(const Location &LocA, const Location &LocB);
const Value *V2, unsigned V2Size);
Value *GetBaseValue(const SCEV *S); Value *GetBaseValue(const SCEV *S);
}; };
@@ -101,17 +100,17 @@ ScalarEvolutionAliasAnalysis::GetBaseValue(const SCEV *S) {
} }
AliasAnalysis::AliasResult AliasAnalysis::AliasResult
ScalarEvolutionAliasAnalysis::alias(const Value *A, unsigned ASize, ScalarEvolutionAliasAnalysis::alias(const Location &LocA,
const Value *B, unsigned BSize) { const Location &LocB) {
// If either of the memory references is empty, it doesn't matter what the // If either of the memory references is empty, it doesn't matter what the
// pointer values are. This allows the code below to ignore this special // pointer values are. This allows the code below to ignore this special
// case. // case.
if (ASize == 0 || BSize == 0) if (LocA.Size == 0 || LocB.Size == 0)
return NoAlias; return NoAlias;
// This is ScalarEvolutionAliasAnalysis. Get the SCEVs! // This is ScalarEvolutionAliasAnalysis. Get the SCEVs!
const SCEV *AS = SE->getSCEV(const_cast<Value *>(A)); const SCEV *AS = SE->getSCEV(const_cast<Value *>(LocA.Ptr));
const SCEV *BS = SE->getSCEV(const_cast<Value *>(B)); const SCEV *BS = SE->getSCEV(const_cast<Value *>(LocB.Ptr));
// If they evaluate to the same expression, it's a MustAlias. // If they evaluate to the same expression, it's a MustAlias.
if (AS == BS) return MustAlias; if (AS == BS) return MustAlias;
@@ -121,8 +120,8 @@ ScalarEvolutionAliasAnalysis::alias(const Value *A, unsigned ASize,
if (SE->getEffectiveSCEVType(AS->getType()) == if (SE->getEffectiveSCEVType(AS->getType()) ==
SE->getEffectiveSCEVType(BS->getType())) { SE->getEffectiveSCEVType(BS->getType())) {
unsigned BitWidth = SE->getTypeSizeInBits(AS->getType()); unsigned BitWidth = SE->getTypeSizeInBits(AS->getType());
APInt ASizeInt(BitWidth, ASize); APInt ASizeInt(BitWidth, LocA.Size);
APInt BSizeInt(BitWidth, BSize); APInt BSizeInt(BitWidth, LocB.Size);
// Compute the difference between the two pointers. // Compute the difference between the two pointers.
const SCEV *BA = SE->getMinusSCEV(BS, AS); const SCEV *BA = SE->getMinusSCEV(BS, AS);
@@ -154,11 +153,15 @@ ScalarEvolutionAliasAnalysis::alias(const Value *A, unsigned ASize,
// inttoptr and ptrtoint operators. // inttoptr and ptrtoint operators.
Value *AO = GetBaseValue(AS); Value *AO = GetBaseValue(AS);
Value *BO = GetBaseValue(BS); Value *BO = GetBaseValue(BS);
if ((AO && AO != A) || (BO && BO != B)) if ((AO && AO != LocA.Ptr) || (BO && BO != LocB.Ptr))
if (alias(AO ? AO : A, AO ? UnknownSize : ASize, if (alias(Location(AO ? AO : LocA.Ptr,
BO ? BO : B, BO ? UnknownSize : BSize) == NoAlias) AO ? +UnknownSize : LocA.Size,
AO ? 0 : LocA.TBAATag),
Location(BO ? BO : LocB.Ptr,
BO ? +UnknownSize : LocB.Size,
BO ? 0 : LocB.TBAATag)) == NoAlias)
return NoAlias; return NoAlias;
// Forward the query to the next analysis. // Forward the query to the next analysis.
return AliasAnalysis::alias(A, ASize, B, BSize); return AliasAnalysis::alias(LocA, LocB);
} }

17
lib/Analysis/TypeBasedAliasAnalysis.cpp
View File

@@ -96,9 +96,8 @@ namespace {
private: private:
virtual void getAnalysisUsage(AnalysisUsage &AU) const; virtual void getAnalysisUsage(AnalysisUsage &AU) const;
virtual AliasResult alias(const Value *V1, unsigned V1Size, virtual AliasResult alias(const Location &LocA, const Location &LocB);
const Value *V2, unsigned V2Size); virtual bool pointsToConstantMemory(const Location &Loc);
virtual bool pointsToConstantMemory(const Value *P);
}; };
} // End of anonymous namespace } // End of anonymous namespace
@@ -118,12 +117,12 @@ TypeBasedAliasAnalysis::getAnalysisUsage(AnalysisUsage &AU) const {
} }
AliasAnalysis::AliasResult AliasAnalysis::AliasResult
TypeBasedAliasAnalysis::alias(const Value *A, unsigned ASize, TypeBasedAliasAnalysis::alias(const Location &LocA,
const Value *B, unsigned BSize) { const Location &LocB) {
// Currently, metadata can only be attached to Instructions. // Currently, metadata can only be attached to Instructions.
const Instruction *AI = dyn_cast<Instruction>(A); const Instruction *AI = dyn_cast<Instruction>(LocA.Ptr);
if (!AI) return MayAlias; if (!AI) return MayAlias;
const Instruction *BI = dyn_cast<Instruction>(B); const Instruction *BI = dyn_cast<Instruction>(LocB.Ptr);
if (!BI) return MayAlias; if (!BI) return MayAlias;
// Get the attached MDNodes. If either value lacks a tbaa MDNode, we must // Get the attached MDNodes. If either value lacks a tbaa MDNode, we must
@@ -175,9 +174,9 @@ TypeBasedAliasAnalysis::alias(const Value *A, unsigned ASize,
return MayAlias; return MayAlias;
} }
bool TypeBasedAliasAnalysis::pointsToConstantMemory(const Value *P) { bool TypeBasedAliasAnalysis::pointsToConstantMemory(const Location &Loc) {
// Currently, metadata can only be attached to Instructions. // Currently, metadata can only be attached to Instructions.
const Instruction *I = dyn_cast<Instruction>(P); const Instruction *I = dyn_cast<Instruction>(Loc.Ptr);
if (!I) return false; if (!I) return false;
MDNode *M = MDNode *M =

9
lib/VMCore/LLVMContext.cpp
View File

@@ -28,9 +28,16 @@ LLVMContext& llvm::getGlobalContext() {
} }
LLVMContext::LLVMContext() : pImpl(new LLVMContextImpl(*this)) { LLVMContext::LLVMContext() : pImpl(new LLVMContextImpl(*this)) {
// Create the first metadata kind, which is always 'dbg'. // Create the fixed metadata kinds. This is done in the same order as the
// MD_* enum values so that they correspond.
// Create the 'dbg' metadata kind.
unsigned DbgID = getMDKindID("dbg"); unsigned DbgID = getMDKindID("dbg");
assert(DbgID == MD_dbg && "dbg kind id drifted"); (void)DbgID; assert(DbgID == MD_dbg && "dbg kind id drifted"); (void)DbgID;
// Create the 'tbaa' metadata kind.
unsigned TBAAID = getMDKindID("tbaa");
assert(TBAAID == MD_tbaa && "tbaa kind id drifted"); (void)TBAAID;
} }
LLVMContext::~LLVMContext() { delete pImpl; } LLVMContext::~LLVMContext() { delete pImpl; }