Make getTypeSizeInBits work correctly for array types; it should return

the number of value bits, not the number of bits of allocation for in-memory
storage.

Make getTypeStoreSize and getTypeAllocSize work consistently for arrays and
vectors.

Fix several places in CodeGen which compute offsets into in-memory vectors
to use TargetData information.

This fixes PR1784.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97064 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/TargetData.cpp

@@ -455,7 +455,7 @@ uint64_t TargetData::getTypeSizeInBits(const Type *Ty) const {
     return getPointerSizeInBits();
   case Type::ArrayTyID: {
     const ArrayType *ATy = cast<ArrayType>(Ty);
-    return getTypeAllocSizeInBits(ATy->getElementType())*ATy->getNumElements();
+    return getTypeSizeInBits(ATy->getElementType())*ATy->getNumElements();
   }
   case Type::StructTyID:
     // Get the layout annotation... which is lazily created on demand.
@@ -484,6 +484,47 @@ uint64_t TargetData::getTypeSizeInBits(const Type *Ty) const {
   return 0;
 }
 
+/// getTypeStoreSize - Return the maximum number of bytes that may be
+/// overwritten by storing the specified type.  For example, returns 5
+/// for i36 and 10 for x86_fp80.
+uint64_t TargetData::getTypeStoreSize(const Type *Ty) const {
+  // Arrays and vectors are allocated as sequences of elements.
+  if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty)) {
+    if (ATy->getNumElements() == 0)
+      return 0;
+    const Type *ElementType = ATy->getElementType();
+    return getTypeAllocSize(ElementType) * (ATy->getNumElements() - 1) +
+           getTypeStoreSize(ElementType);
+  }
+  if (const VectorType *VTy = dyn_cast<VectorType>(Ty)) {
+    const Type *ElementType = VTy->getElementType();
+    return getTypeAllocSize(ElementType) * (VTy->getNumElements() - 1) +
+           getTypeStoreSize(ElementType);
+  }
+
+  return (getTypeSizeInBits(Ty)+7)/8;
+}
+
+/// getTypeAllocSize - Return the offset in bytes between successive objects
+/// of the specified type, including alignment padding.  This is the amount
+/// that alloca reserves for this type.  For example, returns 12 or 16 for
+/// x86_fp80, depending on alignment.
+uint64_t TargetData::getTypeAllocSize(const Type* Ty) const {
+  // Arrays and vectors are allocated as sequences of elements.
+  // Note that this means that things like vectors-of-i1 are not bit-packed
+  // in memory (except on a hypothetical bit-addressable machine). If
+  // someone builds hardware with native vector-of-i1 stores and the idiom
+  // of bitcasting vectors to integers in order to bitpack them for storage
+  // isn't sufficient, TargetData may need new "size" concept.
+  if (const ArrayType *ATy = dyn_cast<ArrayType>(Ty))
+    return getTypeAllocSize(ATy->getElementType()) * ATy->getNumElements();
+  if (const VectorType *VTy = dyn_cast<VectorType>(Ty))
+    return getTypeAllocSize(VTy->getElementType()) * VTy->getNumElements();
+
+  // Round up to the next alignment boundary.
+  return RoundUpAlignment(getTypeStoreSize(Ty), getABITypeAlignment(Ty));
+}
+
 /*!
   \param abi_or_pref Flag that determines which alignment is returned. true
   returns the ABI alignment, false returns the preferred alignment.