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-rw-r--r--contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp95
1 files changed, 38 insertions, 57 deletions
diff --git a/contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp
index 4bb93ee..ae6da1a 100644
--- a/contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp
@@ -13,28 +13,28 @@
//
//===----------------------------------------------------------------------===//
-#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/Passes.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Function.h"
-#include "llvm/GlobalAlias.h"
-#include "llvm/GlobalVariable.h"
-#include "llvm/Instructions.h"
-#include "llvm/IntrinsicInst.h"
-#include "llvm/LLVMContext.h"
-#include "llvm/Operator.h"
-#include "llvm/Pass.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Analysis/CaptureTracking.h"
-#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/InstructionSimplify.h"
+#include "llvm/Analysis/MemoryBuiltins.h"
#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/DataLayout.h"
-#include "llvm/Target/TargetLibraryInfo.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/SmallVector.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GlobalAlias.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Operator.h"
+#include "llvm/Pass.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
+#include "llvm/Target/TargetLibraryInfo.h"
#include <algorithm>
using namespace llvm;
@@ -88,7 +88,7 @@ static uint64_t getObjectSize(const Value *V, const DataLayout &TD,
const TargetLibraryInfo &TLI,
bool RoundToAlign = false) {
uint64_t Size;
- if (getObjectSize(V, Size, &TD, &TLI, RoundToAlign))
+ if (getUnderlyingObjectSize(V, Size, &TD, &TLI, RoundToAlign))
return Size;
return AliasAnalysis::UnknownSize;
}
@@ -631,7 +631,7 @@ BasicAliasAnalysis::getModRefBehavior(const Function *F) {
// For intrinsics, we can check the table.
if (unsigned iid = F->getIntrinsicID()) {
#define GET_INTRINSIC_MODREF_BEHAVIOR
-#include "llvm/Intrinsics.gen"
+#include "llvm/IR/Intrinsics.gen"
#undef GET_INTRINSIC_MODREF_BEHAVIOR
}
@@ -851,9 +851,13 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
// pointers, figure out if the indexes to the GEP tell us anything about the
// derived pointer.
if (const GEPOperator *GEP2 = dyn_cast<GEPOperator>(V2)) {
+ // Do the base pointers alias?
+ AliasResult BaseAlias = aliasCheck(UnderlyingV1, UnknownSize, 0,
+ UnderlyingV2, UnknownSize, 0);
+
// Check for geps of non-aliasing underlying pointers where the offsets are
// identical.
- if (V1Size == V2Size) {
+ if ((BaseAlias == MayAlias) && V1Size == V2Size) {
// Do the base pointers alias assuming type and size.
AliasResult PreciseBaseAlias = aliasCheck(UnderlyingV1, V1Size,
V1TBAAInfo, UnderlyingV2,
@@ -881,10 +885,6 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
GEP1VariableIndices.clear();
}
}
-
- // Do the base pointers alias?
- AliasResult BaseAlias = aliasCheck(UnderlyingV1, UnknownSize, 0,
- UnderlyingV2, UnknownSize, 0);
// If we get a No or May, then return it immediately, no amount of analysis
// will improve this situation.
@@ -1064,39 +1064,20 @@ BasicAliasAnalysis::aliasPHI(const PHINode *PN, uint64_t PNSize,
Location(V2, V2Size, V2TBAAInfo));
if (PN > V2)
std::swap(Locs.first, Locs.second);
-
- AliasResult Alias =
- aliasCheck(PN->getIncomingValue(0), PNSize, PNTBAAInfo,
- PN2->getIncomingValueForBlock(PN->getIncomingBlock(0)),
- V2Size, V2TBAAInfo);
- if (Alias == MayAlias)
- return MayAlias;
-
- // If the first source of the PHI nodes NoAlias and the other inputs are
- // the PHI node itself through some amount of recursion this does not add
- // any new information so just return NoAlias.
- // bb:
- // ptr = ptr2 + 1
- // loop:
- // ptr_phi = phi [bb, ptr], [loop, ptr_plus_one]
- // ptr2_phi = phi [bb, ptr2], [loop, ptr2_plus_one]
- // ...
- // ptr_plus_one = gep ptr_phi, 1
- // ptr2_plus_one = gep ptr2_phi, 1
- // We assume for the recursion that the the phis (ptr_phi, ptr2_phi) do
- // not alias each other.
- bool ArePhisAssumedNoAlias = false;
- AliasResult OrigAliasResult = NoAlias;
- if (Alias == NoAlias) {
- // Pretend the phis do not alias.
- assert(AliasCache.count(Locs) &&
- "There must exist an entry for the phi node");
- OrigAliasResult = AliasCache[Locs];
- AliasCache[Locs] = NoAlias;
- ArePhisAssumedNoAlias = true;
- }
-
- for (unsigned i = 1, e = PN->getNumIncomingValues(); i != e; ++i) {
+ // Analyse the PHIs' inputs under the assumption that the PHIs are
+ // NoAlias.
+ // If the PHIs are May/MustAlias there must be (recursively) an input
+ // operand from outside the PHIs' cycle that is MayAlias/MustAlias or
+ // there must be an operation on the PHIs within the PHIs' value cycle
+ // that causes a MayAlias.
+ // Pretend the phis do not alias.
+ AliasResult Alias = NoAlias;
+ assert(AliasCache.count(Locs) &&
+ "There must exist an entry for the phi node");
+ AliasResult OrigAliasResult = AliasCache[Locs];
+ AliasCache[Locs] = NoAlias;
+
+ for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
AliasResult ThisAlias =
aliasCheck(PN->getIncomingValue(i), PNSize, PNTBAAInfo,
PN2->getIncomingValueForBlock(PN->getIncomingBlock(i)),
@@ -1107,7 +1088,7 @@ BasicAliasAnalysis::aliasPHI(const PHINode *PN, uint64_t PNSize,
}
// Reset if speculation failed.
- if (ArePhisAssumedNoAlias && Alias != NoAlias)
+ if (Alias != NoAlias)
AliasCache[Locs] = OrigAliasResult;
return Alias;
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