Silencing an MSVC warning: '<<' : result of 32-bit shift implicitly converted to...

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

diff --git a/lib/Analysis/Loads.cpp b/lib/Analysis/Loads.cpp
index 65a30f2816fbfcbb711dd366cdd374f494d73668..aed3b04ebcace8ecaa8c419b28fd7ffb036b15c6 100644 (file)
--- a/lib/Analysis/Loads.cpp
+++ b/lib/Analysis/Loads.cpp
@@ -19,6 +19,7 @@
 #include "llvm/IR/GlobalVariable.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
 #include "llvm/IR/Operator.h"
 using namespace llvm;
 
@@ -62,7 +63,8 @@ static bool AreEquivalentAddressValues(const Value *A, const Value *B) {
 /// This uses the pointee type to determine how many bytes need to be safe to
 /// load from the pointer.
 bool llvm::isSafeToLoadUnconditionally(Value *V, Instruction *ScanFrom,
-                                       unsigned Align, const DataLayout *DL) {
+                                       unsigned Align) {
+  const DataLayout &DL = ScanFrom->getModule()->getDataLayout();
   int64_t ByteOffset = 0;
   Value *Base = V;
   Base = GetPointerBaseWithConstantOffset(V, ByteOffset, DL);
@@ -87,19 +89,19 @@ bool llvm::isSafeToLoadUnconditionally(Value *V, Instruction *ScanFrom,
   }
 
   PointerType *AddrTy = cast<PointerType>(V->getType());
-  uint64_t LoadSize = DL ? DL->getTypeStoreSize(AddrTy->getElementType()) : 0;
+  uint64_t LoadSize = DL.getTypeStoreSize(AddrTy->getElementType());
 
   // If we found a base allocated type from either an alloca or global variable,
   // try to see if we are definitively within the allocated region. We need to
   // know the size of the base type and the loaded type to do anything in this
-  // case, so only try this when we have the DataLayout available.
-  if (BaseType && BaseType->isSized() && DL) {
+  // case.
+  if (BaseType && BaseType->isSized()) {
     if (BaseAlign == 0)
-      BaseAlign = DL->getPrefTypeAlignment(BaseType);
+      BaseAlign = DL.getPrefTypeAlignment(BaseType);
 
     if (Align <= BaseAlign) {
       // Check if the load is within the bounds of the underlying object.
-      if (ByteOffset + LoadSize <= DL->getTypeAllocSize(BaseType) &&
+      if (ByteOffset + LoadSize <= DL.getTypeAllocSize(BaseType) &&
           (Align == 0 || (ByteOffset % Align) == 0))
         return true;
     }
@@ -133,16 +135,13 @@ bool llvm::isSafeToLoadUnconditionally(Value *V, Instruction *ScanFrom,
     else
       continue;
 
-    // Handle trivial cases even w/o DataLayout or other work.
+    // Handle trivial cases.
     if (AccessedPtr == V)
       return true;
 
-    if (!DL)
-      continue;
-
     auto *AccessedTy = cast<PointerType>(AccessedPtr->getType());
     if (AreEquivalentAddressValues(AccessedPtr->stripPointerCasts(), V) &&
-        LoadSize <= DL->getTypeStoreSize(AccessedTy->getElementType()))
+        LoadSize <= DL.getTypeStoreSize(AccessedTy->getElementType()))
       return true;
   }
   return false;
@@ -176,8 +175,10 @@ Value *llvm::FindAvailableLoadedValue(Value *Ptr, BasicBlock *ScanBB,
 
   Type *AccessTy = cast<PointerType>(Ptr->getType())->getElementType();
 
-  // If we're using alias analysis to disambiguate get the size of *Ptr.
-  uint64_t AccessSize = AA ? AA->getTypeStoreSize(AccessTy) : 0;
+  const DataLayout &DL = ScanBB->getModule()->getDataLayout();
+
+  // Try to get the store size for the type.
+  uint64_t AccessSize = DL.getTypeStoreSize(AccessTy);
 
   Value *StrippedPtr = Ptr->stripPointerCasts();
 
@@ -202,7 +203,7 @@ Value *llvm::FindAvailableLoadedValue(Value *Ptr, BasicBlock *ScanBB,
     if (LoadInst *LI = dyn_cast<LoadInst>(Inst))
       if (AreEquivalentAddressValues(
               LI->getPointerOperand()->stripPointerCasts(), StrippedPtr) &&
-          CastInst::isBitCastable(LI->getType(), AccessTy)) {
+          CastInst::isBitOrNoopPointerCastable(LI->getType(), AccessTy, DL)) {
         if (AATags)
           LI->getAAMetadata(*AATags);
         return LI;
@@ -214,17 +215,19 @@ Value *llvm::FindAvailableLoadedValue(Value *Ptr, BasicBlock *ScanBB,
       // (This is true even if the store is volatile or atomic, although
       // those cases are unlikely.)
       if (AreEquivalentAddressValues(StorePtr, StrippedPtr) &&
-          CastInst::isBitCastable(SI->getValueOperand()->getType(), AccessTy)) {
+          CastInst::isBitOrNoopPointerCastable(SI->getValueOperand()->getType(),
+                                               AccessTy, DL)) {
         if (AATags)
           SI->getAAMetadata(*AATags);
         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
-      // for reg2mem'd code.
+      // If both StrippedPtr and StorePtr reach all the way to an alloca or
+      // global and they are different, ignore the store. This is a trivial form
+      // of alias analysis that is important for reg2mem'd code.
       if ((isa<AllocaInst>(StrippedPtr) || isa<GlobalVariable>(StrippedPtr)) &&
-          (isa<AllocaInst>(StorePtr) || isa<GlobalVariable>(StorePtr)))
+          (isa<AllocaInst>(StorePtr) || isa<GlobalVariable>(StorePtr)) &&
+          StrippedPtr != StorePtr)
         continue;
 
       // If we have alias analysis and it says the store won't modify the loaded