Various cleanups and efficiency improvements

[oota-llvm.git] / lib / Transforms / TransformInternals.cpp

diff --git a/lib/Transforms/TransformInternals.cpp b/lib/Transforms/TransformInternals.cpp
index d3641e6f0dfce884e88a33f18ec34ff806270382..3a1d51c3a02c9518386bfec31fdb74ce1eaac494 100644 (file)
--- a/lib/Transforms/TransformInternals.cpp
+++ b/lib/Transforms/TransformInternals.cpp
@@ -1,4 +1,11 @@
-//===-- TransformInternals.cpp - Implement shared functions for transforms --=//
+//===- TransformInternals.cpp - Implement shared functions for transforms -===//
+// 
+//                     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 defines shared functions used by the different components of the
 //  Transforms library.
@@ -53,17 +60,23 @@ const Type *getStructOffsetType(const Type *Ty, unsigned &Offset,
   uint64_t ThisOffset;
   const Type *NextType;
   if (const StructType *STy = dyn_cast<StructType>(Ty)) {
+    if (STy->getElementTypes().empty()) {
+      Offset = 0;
+      return STy;
+    }
+
     ThisOffset = Offset;
     NextType = getStructOffsetStep(STy, ThisOffset, Indices, TD);
   } else if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
-    assert(Offset < TD.getTypeSize(ATy) && "Offset not in composite!");
+    assert(Offset == 0 || Offset < TD.getTypeSize(ATy) &&
+           "Offset not in composite!");
 
     NextType = ATy->getElementType();
     unsigned ChildSize = TD.getTypeSize(NextType);
     Indices.push_back(ConstantSInt::get(Type::LongTy, Offset/ChildSize));
     ThisOffset = (Offset/ChildSize)*ChildSize;
   } else {
-    Offset = 0;   // Return the offset that we were able to acheive
+    Offset = 0;   // Return the offset that we were able to achieve
     return Ty;    // Return the leaf type
   }
 
@@ -74,12 +87,12 @@ const Type *getStructOffsetType(const Type *Ty, unsigned &Offset,
   return LeafTy;
 }
 
-// ConvertableToGEP - This function returns true if the specified value V is
+// ConvertibleToGEP - This function returns true if the specified value V is
 // a valid index into a pointer of type Ty.  If it is valid, Idx is filled in
 // with the values that would be appropriate to make this a getelementptr
 // instruction.  The type returned is the root type that the GEP would point to
 //
-const Type *ConvertableToGEP(const Type *Ty, Value *OffsetVal,
+const Type *ConvertibleToGEP(const Type *Ty, Value *OffsetVal,
                              std::vector<Value*> &Indices,
                              const TargetData &TD,
                              BasicBlock::iterator *BI) {
@@ -118,6 +131,7 @@ const Type *ConvertableToGEP(const Type *Ty, Value *OffsetVal,
       if (!ElTy->isSized() || (isa<PointerType>(CompTy) && !Indices.empty()))
         return 0; // Type is unreasonable... escape!
       unsigned ElSize = TD.getTypeSize(ElTy);
+      if (ElSize == 0) return 0;   // Avoid division by zero...
       int64_t ElSizeS = ElSize;
 
       // See if the user is indexing into a different cell of this array...