From 8477f60525ea1382590ddc308b2858c7ad653b62 Mon Sep 17 00:00:00 2001
From: Warren Hunt <whunt@google.com>
Date: Tue, 14 Jan 2014 00:31:30 +0000
Subject: [PATCH] [ms-abi] Report VBPtrOffset correctly

Although VBPtrs were being placed correctly by the ms-abi layout engine,
their offsets were being improperly reported to the ASTRecordLayout
builder due to a bug.  This patch fixes that and fixes the test cases to
use the correct values.
y


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@199168 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/AST/RecordLayoutBuilder.cpp                       | 11 +++++------
 test/CodeGenCXX/microsoft-abi-member-pointers.cpp     |  4 ++--
 ...soft-abi-vtables-virtual-inheritance-vtordisps.cpp |  2 +-
 test/CodeGenCXX/virtual-base-cast.cpp                 |  4 ++--
 4 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/lib/AST/RecordLayoutBuilder.cpp b/lib/AST/RecordLayoutBuilder.cpp
index fd0a463012..6b3a431da2 100644
--- a/lib/AST/RecordLayoutBuilder.cpp
+++ b/lib/AST/RecordLayoutBuilder.cpp
@@ -2341,6 +2341,10 @@ MicrosoftRecordLayoutBuilder::layoutNonVirtualBases(const CXXRecordDecl *RD) {
   // Set our VBPtroffset if we know it at this point.
   if (!HasVBPtr)
     VBPtrOffset = CharUnits::fromQuantity(-1);
+  else if (SharedVBPtrBase) {
+    const ASTRecordLayout &Layout = Context.getASTRecordLayout(SharedVBPtrBase);
+    VBPtrOffset = Bases[SharedVBPtrBase] + Layout.getVBPtrOffset();
+  }
 }
 
 void MicrosoftRecordLayoutBuilder::layoutNonVirtualBase(
@@ -2444,13 +2448,8 @@ MicrosoftRecordLayoutBuilder::layoutZeroWidthBitField(const FieldDecl *FD) {
 }
 
 void MicrosoftRecordLayoutBuilder::injectVBPtr(const CXXRecordDecl *RD) {
-  if (!HasVBPtr)
+  if (!HasVBPtr || SharedVBPtrBase)
     return;
-  if (SharedVBPtrBase) {
-    const ASTRecordLayout &Layout = Context.getASTRecordLayout(SharedVBPtrBase);
-    VBPtrOffset = Bases[SharedVBPtrBase] + Layout.getVBPtrOffset();
-    return;
-  }
   // Inject the VBPointer at the injection site.
   CharUnits InjectionSite = VBPtrOffset;
   // But before we do, make sure it's properly aligned.
diff --git a/test/CodeGenCXX/microsoft-abi-member-pointers.cpp b/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
index ba7bc899f5..dca9f170a9 100644
--- a/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
+++ b/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
@@ -95,7 +95,7 @@ void (UnspecSingle::*us_f_mp)() = &UnspecSingle::foo;
 // CHECK: @"\01?v_f_mp@Const@@3P8Virtual@@AEXXZQ2@" =
 // CHECK:   global { i8*, i32, i32 } { i8* bitcast ({{.*}} @"\01?foo@Virtual@@QAEXXZ" to i8*), i32 0, i32 0 }, align 4
 // CHECK: @"\01?u_f_mp@Const@@3P8Unspecified@@AEXXZQ2@" =
-// CHECK:   global { i8*, i32, i32, i32 } { i8* bitcast ({{.*}} @"\01?foo@Unspecified@@QAEXXZ" to i8*), i32 0, i32 20, i32 0 }, align 4
+// CHECK:   global { i8*, i32, i32, i32 } { i8* bitcast ({{.*}} @"\01?foo@Unspecified@@QAEXXZ" to i8*), i32 0, i32 12, i32 0 }, align 4
 // CHECK: @"\01?us_f_mp@Const@@3P8UnspecSingle@@AEXXZQ2@" =
 // CHECK:   global { i8*, i32, i32, i32 } { i8* bitcast ({{.*}} @"\01?foo@UnspecSingle@@QAEXXZ" to i8*), i32 0, i32 0, i32 0 }, align 4
 }
@@ -167,7 +167,7 @@ void EmitNonVirtualMemberPointers() {
 // CHECK:     { i8* bitcast (void (%{{.*}}*)* @"\01?foo@Virtual@@QAEXXZ" to i8*), i32 0, i32 0 },
 // CHECK:     { i8*, i32, i32 }* %{{.*}}, align 4
 // CHECK:   store { i8*, i32, i32, i32 }
-// CHECK:     { i8* bitcast (void (%{{.*}}*)* @"\01?foo@Unspecified@@QAEXXZ" to i8*), i32 0, i32 20, i32 0 },
+// CHECK:     { i8* bitcast (void (%{{.*}}*)* @"\01?foo@Unspecified@@QAEXXZ" to i8*), i32 0, i32 12, i32 0 },
 // CHECK:     { i8*, i32, i32, i32 }* %{{.*}}, align 4
 // CHECK:   store { i8*, i32, i32, i32 }
 // CHECK:     { i8* bitcast (void (%{{.*}}*)* @"\01?foo@UnspecWithVBPtr@@QAEXXZ" to i8*),
diff --git a/test/CodeGenCXX/microsoft-abi-vtables-virtual-inheritance-vtordisps.cpp b/test/CodeGenCXX/microsoft-abi-vtables-virtual-inheritance-vtordisps.cpp
index 2976d1967c..3fef0e4093 100644
--- a/test/CodeGenCXX/microsoft-abi-vtables-virtual-inheritance-vtordisps.cpp
+++ b/test/CodeGenCXX/microsoft-abi-vtables-virtual-inheritance-vtordisps.cpp
@@ -264,7 +264,7 @@ struct H : Z, A {
 
   // VTABLE-EXTENDED-H: VFTable for 'V1' in 'simple::A' in 'extended::A' in 'extended::H' (2 entries).
   // VTABLE-EXTENDED-H-NEXT: 0 | void simple::A::f()
-  // VTABLE-EXTENDED-H-NEXT:     [this adjustment: vtordisp at -4, vbptr at 4 to the left,
+  // VTABLE-EXTENDED-H-NEXT:     [this adjustment: vtordisp at -4, vbptr at 8 to the left,
   // VTABLE-EXTENDED-H-NEXT:      vboffset at 8 in the vbtable, 8 non-virtual]
 
   // MANGLING-DAG: @"\01?f@A@simple@@$R477PPPPPPPM@7AEXXZ"
diff --git a/test/CodeGenCXX/virtual-base-cast.cpp b/test/CodeGenCXX/virtual-base-cast.cpp
index e35f41e1ca..40e68f6722 100644
--- a/test/CodeGenCXX/virtual-base-cast.cpp
+++ b/test/CodeGenCXX/virtual-base-cast.cpp
@@ -77,13 +77,13 @@ BB* d() { return y; }
 // Same as 'c' except the vbptr offset is 4, changing the initial GEP and the
 // final add.
 // MSVC: @"\01?d@@YAPAUBB@@XZ"() [[NUW:#[0-9]+]] {
-// MSVC:   %[[vbptr_off:.*]] = getelementptr inbounds i8* {{.*}}, i32 12
+// MSVC:   %[[vbptr_off:.*]] = getelementptr inbounds i8* {{.*}}, i32 4
 // MSVC:   %[[vbptr:.*]] = bitcast i8* %[[vbptr_off]] to i8**
 // MSVC:   %[[vbtable:.*]] = load i8** %[[vbptr]]
 // MSVC:   %[[entry:.*]] = getelementptr inbounds i8* {{.*}}, i32 16
 // MSVC:   %[[entry_i32:.*]] = bitcast i8* %[[entry]] to i32*
 // MSVC:   %[[offset:.*]] = load i32* %[[entry_i32]]
-// MSVC:   add nsw i32 12, %[[offset]]
+// MSVC:   add nsw i32 4, %[[offset]]
 // MSVC: }
 
 // CHECK: attributes [[NUW]] = { nounwind{{.*}} }
-- 
2.40.0