Index: llvm/trunk/lib/Transforms/IPO/WholeProgramDevirt.cpp
===================================================================
--- llvm/trunk/lib/Transforms/IPO/WholeProgramDevirt.cpp
+++ llvm/trunk/lib/Transforms/IPO/WholeProgramDevirt.cpp
@@ -1302,10 +1302,12 @@
   if (B.Before.Bytes.empty() && B.After.Bytes.empty())
     return;
 
-  // Align each byte array to pointer width.
-  unsigned PointerSize = M.getDataLayout().getPointerSize();
-  B.Before.Bytes.resize(alignTo(B.Before.Bytes.size(), PointerSize));
-  B.After.Bytes.resize(alignTo(B.After.Bytes.size(), PointerSize));
+  // Align the before byte array to the global's minimum alignment so that we
+  // don't break any alignment requirements on the global.
+  unsigned Align = B.GV->getAlignment();
+  if (Align == 0)
+    Align = M.getDataLayout().getABITypeAlignment(B.GV->getValueType());
+  B.Before.Bytes.resize(alignTo(B.Before.Bytes.size(), Align));
 
   // Before was stored in reverse order; flip it now.
   for (size_t I = 0, Size = B.Before.Bytes.size(); I != Size / 2; ++I)
@@ -1322,6 +1324,7 @@
                          GlobalVariable::PrivateLinkage, NewInit, "", B.GV);
   NewGV->setSection(B.GV->getSection());
   NewGV->setComdat(B.GV->getComdat());
+  NewGV->setAlignment(B.GV->getAlignment());
 
   // Copy the original vtable's metadata to the anonymous global, adjusting
   // offsets as required.
Index: llvm/trunk/test/Transforms/WholeProgramDevirt/virtual-const-prop-begin.ll
===================================================================
--- llvm/trunk/test/Transforms/WholeProgramDevirt/virtual-const-prop-begin.ll
+++ llvm/trunk/test/Transforms/WholeProgramDevirt/virtual-const-prop-begin.ll
@@ -17,19 +17,19 @@
 i8* bitcast (i32 (i8*)* @vf2i32 to i8*)
 ], !type !0
 
-; CHECK: [[VT3DATA:@[^ ]*]] = private constant { [8 x i8], [3 x i8*], [0 x i8] } { [8 x i8] c"\00\00\00\01\03\00\00\00", [3 x i8*] [i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i32 (i8*)* @vf3i32 to i8*)], [0 x i8] zeroinitializer }, !type [[T8]]
+; CHECK: [[VT3DATA:@[^ ]*]] = private constant { [5 x i8], [3 x i8*], [0 x i8] } { [5 x i8] c"\01\03\00\00\00", [3 x i8*] [i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i32 (i8*)* @vf3i32 to i8*)], [0 x i8] zeroinitializer }, align 1, !type [[T5:![0-9]+]]
 @vt3 = constant [3 x i8*] [
 i8* bitcast (i1 (i8*)* @vf0i1 to i8*),
 i8* bitcast (i1 (i8*)* @vf1i1 to i8*),
 i8* bitcast (i32 (i8*)* @vf3i32 to i8*)
-], !type !0
+], align 1, !type !0
 
-; CHECK: [[VT4DATA:@[^ ]*]] = private constant { [8 x i8], [3 x i8*], [0 x i8] } { [8 x i8] c"\00\00\00\02\04\00\00\00", [3 x i8*] [i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i32 (i8*)* @vf4i32 to i8*)], [0 x i8] zeroinitializer }, !type [[T8]]
+; CHECK: [[VT4DATA:@[^ ]*]] = private constant { [16 x i8], [3 x i8*], [0 x i8] } { [16 x i8] c"\00\00\00\00\00\00\00\00\00\00\00\02\04\00\00\00", [3 x i8*] [i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i32 (i8*)* @vf4i32 to i8*)], [0 x i8] zeroinitializer },  align 16, !type [[T16:![0-9]+]]
 @vt4 = constant [3 x i8*] [
 i8* bitcast (i1 (i8*)* @vf1i1 to i8*),
 i8* bitcast (i1 (i8*)* @vf0i1 to i8*),
 i8* bitcast (i32 (i8*)* @vf4i32 to i8*)
-], !type !0
+], align 16, !type !0
 
 ; CHECK: @vt5 = {{.*}}, !type [[T0:![0-9]+]]
 @vt5 = constant [3 x i8*] [
@@ -40,8 +40,8 @@
 
 ; CHECK: @vt1 = alias [3 x i8*], getelementptr inbounds ({ [8 x i8], [3 x i8*], [0 x i8] }, { [8 x i8], [3 x i8*], [0 x i8] }* [[VT1DATA]], i32 0, i32 1)
 ; CHECK: @vt2 = alias [3 x i8*], getelementptr inbounds ({ [8 x i8], [3 x i8*], [0 x i8] }, { [8 x i8], [3 x i8*], [0 x i8] }* [[VT2DATA]], i32 0, i32 1)
-; CHECK: @vt3 = alias [3 x i8*], getelementptr inbounds ({ [8 x i8], [3 x i8*], [0 x i8] }, { [8 x i8], [3 x i8*], [0 x i8] }* [[VT3DATA]], i32 0, i32 1)
-; CHECK: @vt4 = alias [3 x i8*], getelementptr inbounds ({ [8 x i8], [3 x i8*], [0 x i8] }, { [8 x i8], [3 x i8*], [0 x i8] }* [[VT4DATA]], i32 0, i32 1)
+; CHECK: @vt3 = alias [3 x i8*], getelementptr inbounds ({ [5 x i8], [3 x i8*], [0 x i8] }, { [5 x i8], [3 x i8*], [0 x i8] }* [[VT3DATA]], i32 0, i32 1)
+; CHECK: @vt4 = alias [3 x i8*], getelementptr inbounds ({ [16 x i8], [3 x i8*], [0 x i8] }, { [16 x i8], [3 x i8*], [0 x i8] }* [[VT4DATA]], i32 0, i32 1)
 
 define i1 @vf0i1(i8* %this) readnone {
   ret i1 0
@@ -134,6 +134,8 @@
 declare void @__cxa_pure_virtual()
 
 ; CHECK: [[T8]] = !{i32 8, !"typeid"}
+; CHECK: [[T5]] = !{i32 5, !"typeid"}
+; CHECK: [[T16]] = !{i32 16, !"typeid"}
 ; CHECK: [[T0]] = !{i32 0, !"typeid"}
 
 !0 = !{i32 0, !"typeid"}
Index: llvm/trunk/test/Transforms/WholeProgramDevirt/virtual-const-prop-end.ll
===================================================================
--- llvm/trunk/test/Transforms/WholeProgramDevirt/virtual-const-prop-end.ll
+++ llvm/trunk/test/Transforms/WholeProgramDevirt/virtual-const-prop-end.ll
@@ -3,7 +3,7 @@
 target datalayout = "e-p:64:64"
 target triple = "x86_64-unknown-linux-gnu"
 
-; CHECK: [[VT1DATA:@[^ ]*]] = private constant { [0 x i8], [4 x i8*], [8 x i8] } { [0 x i8] zeroinitializer, [4 x i8*] [i8* null, i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i32 (i8*)* @vf1i32 to i8*)], [8 x i8] c"\01\00\00\00\01\00\00\00" }, !type [[T8:![0-9]+]]
+; CHECK: [[VT1DATA:@[^ ]*]] = private constant { [0 x i8], [4 x i8*], [5 x i8] } { [0 x i8] zeroinitializer, [4 x i8*] [i8* null, i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i32 (i8*)* @vf1i32 to i8*)], [5 x i8] c"\01\00\00\00\01" }, !type [[T8:![0-9]+]]
 @vt1 = constant [4 x i8*] [
 i8* null,
 i8* bitcast (i1 (i8*)* @vf0i1 to i8*),
@@ -11,14 +11,14 @@
 i8* bitcast (i32 (i8*)* @vf1i32 to i8*)
 ], !type !1
 
-; CHECK: [[VT2DATA:@[^ ]*]] = private constant { [0 x i8], [3 x i8*], [8 x i8] } { [0 x i8] zeroinitializer, [3 x i8*] [i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i32 (i8*)* @vf2i32 to i8*)], [8 x i8] c"\02\00\00\00\02\00\00\00" }, !type [[T0:![0-9]+]]
+; CHECK: [[VT2DATA:@[^ ]*]] = private constant { [0 x i8], [3 x i8*], [5 x i8] } { [0 x i8] zeroinitializer, [3 x i8*] [i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i32 (i8*)* @vf2i32 to i8*)], [5 x i8] c"\02\00\00\00\02" }, !type [[T0:![0-9]+]]
 @vt2 = constant [3 x i8*] [
 i8* bitcast (i1 (i8*)* @vf1i1 to i8*),
 i8* bitcast (i1 (i8*)* @vf0i1 to i8*),
 i8* bitcast (i32 (i8*)* @vf2i32 to i8*)
 ], !type !0
 
-; CHECK: [[VT3DATA:@[^ ]*]] = private constant { [0 x i8], [4 x i8*], [8 x i8] } { [0 x i8] zeroinitializer, [4 x i8*] [i8* null, i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i32 (i8*)* @vf3i32 to i8*)], [8 x i8] c"\03\00\00\00\01\00\00\00" }, !type [[T8]]
+; CHECK: [[VT3DATA:@[^ ]*]] = private constant { [0 x i8], [4 x i8*], [5 x i8] } { [0 x i8] zeroinitializer, [4 x i8*] [i8* null, i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i32 (i8*)* @vf3i32 to i8*)], [5 x i8] c"\03\00\00\00\01" }, !type [[T8]]
 @vt3 = constant [4 x i8*] [
 i8* null,
 i8* bitcast (i1 (i8*)* @vf0i1 to i8*),
@@ -26,17 +26,17 @@
 i8* bitcast (i32 (i8*)* @vf3i32 to i8*)
 ], !type !1
 
-; CHECK: [[VT4DATA:@[^ ]*]] = private constant { [0 x i8], [3 x i8*], [8 x i8] } { [0 x i8] zeroinitializer, [3 x i8*] [i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i32 (i8*)* @vf4i32 to i8*)], [8 x i8] c"\04\00\00\00\02\00\00\00" }, !type [[T0]]
+; CHECK: [[VT4DATA:@[^ ]*]] = private constant { [0 x i8], [3 x i8*], [5 x i8] } { [0 x i8] zeroinitializer, [3 x i8*] [i8* bitcast (i1 (i8*)* @vf1i1 to i8*), i8* bitcast (i1 (i8*)* @vf0i1 to i8*), i8* bitcast (i32 (i8*)* @vf4i32 to i8*)], [5 x i8] c"\04\00\00\00\02" }, !type [[T0]]
 @vt4 = constant [3 x i8*] [
 i8* bitcast (i1 (i8*)* @vf1i1 to i8*),
 i8* bitcast (i1 (i8*)* @vf0i1 to i8*),
 i8* bitcast (i32 (i8*)* @vf4i32 to i8*)
 ], !type !0
 
-; CHECK: @vt1 = alias [4 x i8*], getelementptr inbounds ({ [0 x i8], [4 x i8*], [8 x i8] }, { [0 x i8], [4 x i8*], [8 x i8] }* [[VT1DATA]], i32 0, i32 1)
-; CHECK: @vt2 = alias [3 x i8*], getelementptr inbounds ({ [0 x i8], [3 x i8*], [8 x i8] }, { [0 x i8], [3 x i8*], [8 x i8] }* [[VT2DATA]], i32 0, i32 1)
-; CHECK: @vt3 = alias [4 x i8*], getelementptr inbounds ({ [0 x i8], [4 x i8*], [8 x i8] }, { [0 x i8], [4 x i8*], [8 x i8] }* [[VT3DATA]], i32 0, i32 1)
-; CHECK: @vt4 = alias [3 x i8*], getelementptr inbounds ({ [0 x i8], [3 x i8*], [8 x i8] }, { [0 x i8], [3 x i8*], [8 x i8] }* [[VT4DATA]], i32 0, i32 1)
+; CHECK: @vt1 = alias [4 x i8*], getelementptr inbounds ({ [0 x i8], [4 x i8*], [5 x i8] }, { [0 x i8], [4 x i8*], [5 x i8] }* [[VT1DATA]], i32 0, i32 1)
+; CHECK: @vt2 = alias [3 x i8*], getelementptr inbounds ({ [0 x i8], [3 x i8*], [5 x i8] }, { [0 x i8], [3 x i8*], [5 x i8] }* [[VT2DATA]], i32 0, i32 1)
+; CHECK: @vt3 = alias [4 x i8*], getelementptr inbounds ({ [0 x i8], [4 x i8*], [5 x i8] }, { [0 x i8], [4 x i8*], [5 x i8] }* [[VT3DATA]], i32 0, i32 1)
+; CHECK: @vt4 = alias [3 x i8*], getelementptr inbounds ({ [0 x i8], [3 x i8*], [5 x i8] }, { [0 x i8], [3 x i8*], [5 x i8] }* [[VT4DATA]], i32 0, i32 1)
 
 define i1 @vf0i1(i8* %this) readnone {
   ret i1 0