add support for PHI nodes to ObjectSizeOffsetVisitor

[oota-llvm.git] / lib / Analysis / Loads.cpp

diff --git a/lib/Analysis/Loads.cpp b/lib/Analysis/Loads.cpp
index 0e6bcbfae4f6546ddf2f5d383df17bb70783c894..73aa8b49cda584dd9ef4c36618cd959239c29407 100644 (file)
--- a/lib/Analysis/Loads.cpp
+++ b/lib/Analysis/Loads.cpp
@@ -13,10 +13,11 @@
 
 #include "llvm/Analysis/Loads.h"
 #include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Target/TargetData.h"
+#include "llvm/DataLayout.h"
 #include "llvm/GlobalAlias.h"
 #include "llvm/GlobalVariable.h"
 #include "llvm/IntrinsicInst.h"
+#include "llvm/LLVMContext.h"
 #include "llvm/Operator.h"
 using namespace llvm;
 
@@ -51,8 +52,8 @@ static bool AreEquivalentAddressValues(const Value *A, const Value *B) {
 /// bitcasts to get back to the underlying object being addressed, keeping
 /// track of the offset in bytes from the GEPs relative to the result.
 /// This is closely related to GetUnderlyingObject but is located
-/// here to avoid making VMCore depend on TargetData.
-static Value *getUnderlyingObjectWithOffset(Value *V, const TargetData *TD,
+/// here to avoid making VMCore depend on DataLayout.
+static Value *getUnderlyingObjectWithOffset(Value *V, const DataLayout *TD,
                                             uint64_t &ByteOffset,
                                             unsigned MaxLookup = 6) {
   if (!V->getType()->isPointerTy())
@@ -84,7 +85,7 @@ static Value *getUnderlyingObjectWithOffset(Value *V, const TargetData *TD,
 /// specified pointer, we do a quick local scan of the basic block containing
 /// ScanFrom, to determine if the address is already accessed.
 bool llvm::isSafeToLoadUnconditionally(Value *V, Instruction *ScanFrom,
-                                       unsigned Align, const TargetData *TD) {
+                                       unsigned Align, const DataLayout *TD) {
   uint64_t ByteOffset = 0;
   Value *Base = V;
   if (TD)
@@ -160,10 +161,15 @@ bool llvm::isSafeToLoadUnconditionally(Value *V, Instruction *ScanFrom,
 /// MaxInstsToScan specifies the maximum instructions to scan in the block.  If
 /// it is set to 0, it will scan the whole block. You can also optionally
 /// specify an alias analysis implementation, which makes this more precise.
+///
+/// If TBAATag is non-null and a load or store is found, the TBAA tag from the
+/// load or store is recorded there.  If there is no TBAA tag or if no access
+/// is found, it is left unmodified.
 Value *llvm::FindAvailableLoadedValue(Value *Ptr, BasicBlock *ScanBB,
                                       BasicBlock::iterator &ScanFrom,
                                       unsigned MaxInstsToScan,
-                                      AliasAnalysis *AA) {
+                                      AliasAnalysis *AA,
+                                      MDNode **TBAATag) {
   if (MaxInstsToScan == 0) MaxInstsToScan = ~0U;
 
   // If we're using alias analysis to disambiguate get the size of *Ptr.
@@ -191,15 +197,19 @@ Value *llvm::FindAvailableLoadedValue(Value *Ptr, BasicBlock *ScanBB,
     // (This is true even if the load is volatile or atomic, although
     // those cases are unlikely.)
     if (LoadInst *LI = dyn_cast<LoadInst>(Inst))
-      if (AreEquivalentAddressValues(LI->getOperand(0), Ptr))
+      if (AreEquivalentAddressValues(LI->getOperand(0), Ptr)) {
+        if (TBAATag) *TBAATag = LI->getMetadata(LLVMContext::MD_tbaa);
         return LI;
+      }
     
     if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
       // If this is a store through Ptr, the value is available!
       // (This is true even if the store is volatile or atomic, although
       // those cases are unlikely.)
-      if (AreEquivalentAddressValues(SI->getOperand(1), Ptr))
+      if (AreEquivalentAddressValues(SI->getOperand(1), Ptr)) {
+        if (TBAATag) *TBAATag = SI->getMetadata(LLVMContext::MD_tbaa);
         return SI->getOperand(0);
+      }
       
       // If Ptr is an alloca and this is a store to a different alloca, ignore
       // the store.  This is a trivial form of alias analysis that is important