From ae6f1fa36b020c89b0f44c4b4222d0f5fd9b6326 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Fri, 16 Feb 2007 22:25:34 +0000
Subject: [PATCH] simplify some code, ensure that packed structures get abi
 alignment of 1.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34352 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/TargetData.cpp | 29 +++++++++++------------------
 1 file changed, 11 insertions(+), 18 deletions(-)

diff --git a/lib/Target/TargetData.cpp b/lib/Target/TargetData.cpp
index 3f9da2bc090..3be2f11e196 100644
--- a/lib/Target/TargetData.cpp
+++ b/lib/Target/TargetData.cpp
@@ -442,8 +442,7 @@ uint64_t TargetData::getTypeSizeInBits(const Type *Ty) const {
   Get the ABI (\a abi_or_pref == true) or preferred alignment (\a abi_or_pref
   == false) for the requested type \a Ty.
  */
-unsigned char TargetData::getAlignment(const Type *Ty, bool abi_or_pref) const
-{
+unsigned char TargetData::getAlignment(const Type *Ty, bool abi_or_pref) const {
   int AlignType = -1;
 
   assert(Ty->isSized() && "Cannot getTypeInfo() on a type that is unsized!");
@@ -454,27 +453,21 @@ unsigned char TargetData::getAlignment(const Type *Ty, bool abi_or_pref) const
     return (abi_or_pref
             ? getPointerABIAlignment()
             : getPointerPrefAlignment());
-  case Type::ArrayTyID: {
-    const ArrayType *ATy = cast<ArrayType>(Ty);
-    return (abi_or_pref
-            ? getABITypeAlignment(ATy->getElementType())
-            : getPrefTypeAlignment(ATy->getElementType()));
-  }
+  case Type::ArrayTyID:
+    return getAlignment(cast<ArrayType>(Ty)->getElementType(), abi_or_pref);
+    
   case Type::StructTyID: {
-      // Get the layout annotation... which is lazily created on demand.
+    // Packed structure types always have an ABI alignment of one.
+    if (cast<StructType>(Ty)->isPacked() && abi_or_pref)
+      return 1;
+    
+    // Get the layout annotation... which is lazily created on demand.
     const StructLayout *Layout = getStructLayout(cast<StructType>(Ty));
     const TargetAlignElem &elem = getAlignment(AGGREGATE_ALIGN, 0);
     assert(validAlignment(elem)
            && "Aggregate alignment return invalid in getAlignment");
-    if (abi_or_pref) {
-      return (elem.ABIAlign < Layout->getAlignment()
-              ? Layout->StructAlignment
-              : elem.ABIAlign);
-    } else {
-      return (elem.PrefAlign < Layout->getAlignment()
-              ? Layout->StructAlignment
-              : elem.PrefAlign);
-    }
+    unsigned Align = abi_or_pref ? elem.ABIAlign : elem.PrefAlign;
+    return Align < Layout->getAlignment() ? Layout->StructAlignment : Align;
   }
   case Type::IntegerTyID:
   case Type::VoidTyID: