From: Reid Kleckner <rnk@google.com>
Date: Fri, 1 Jul 2016 02:41:25 +0000 (+0000)
Subject: [DebugInfo] Set DISubprogram ThisAdjustment in the MS ABI
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=dc7857b421d9a39eac38e824911fa63587cb3172;p=clang

[DebugInfo] Set DISubprogram ThisAdjustment in the MS ABI

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@274326 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CGCXXABI.h b/lib/CodeGen/CGCXXABI.h
index 8c0f6c2efd..9e10ec068e 100644
--- a/lib/CodeGen/CGCXXABI.h
+++ b/lib/CodeGen/CGCXXABI.h
@@ -336,6 +336,12 @@ public:
   virtual void addImplicitStructorParams(CodeGenFunction &CGF, QualType &ResTy,
                                          FunctionArgList &Params) = 0;
 
+  /// Get the ABI-specific "this" parameter adjustment to apply in the prologue
+  /// of a virtual function.
+  virtual CharUnits getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD) {
+    return CharUnits::Zero();
+  }
+
   /// Perform ABI-specific "this" parameter adjustment in a virtual function
   /// prologue.
   virtual llvm::Value *adjustThisParameterInVirtualFunctionPrologue(
diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index ab0ee6cdbe..13461980a4 100644
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -1206,6 +1206,7 @@ llvm::DISubprogram *CGDebugInfo::CreateCXXMemberFunction(
   unsigned Virtuality = 0;
   unsigned VIndex = 0;
   unsigned Flags = 0;
+  int ThisAdjustment = 0;
 
   if (Method->isVirtual()) {
     if (Method->isPure())
@@ -1235,9 +1236,12 @@ llvm::DISubprogram *CGDebugInfo::CreateCXXMemberFunction(
       if (Method->begin_overridden_methods() == Method->end_overridden_methods())
         Flags |= llvm::DINode::FlagIntroducedVirtual;
 
-      // FIXME: Pass down ML.VFPtrOffset and ML.VBTableIndex. The debugger needs
-      // these to synthesize a call to a virtual method in a complex inheritance
-      // hierarchy.
+      // The 'this' adjustment accounts for both the virtual and non-virtual
+      // portions of the adjustment. Presumably the debugger only uses it when
+      // it knows the dynamic type of an object.
+      ThisAdjustment = CGM.getCXXABI()
+                           .getVirtualFunctionPrologueThisAdjustment(GD)
+                           .getQuantity();
     }
     ContainingType = RecordTy;
   }
@@ -1263,9 +1267,9 @@ llvm::DISubprogram *CGDebugInfo::CreateCXXMemberFunction(
   llvm::DINodeArray TParamsArray = CollectFunctionTemplateParams(Method, Unit);
   llvm::DISubprogram *SP = DBuilder.createMethod(
       RecordTy, MethodName, MethodLinkageName, MethodDefUnit, MethodLine,
-      MethodTy, /*isLocalToUnit=*/false,
-      /* isDefinition=*/false, Virtuality, VIndex, ContainingType, Flags,
-      CGM.getLangOpts().Optimize, TParamsArray.get());
+      MethodTy, /*isLocalToUnit=*/false, /*isDefinition=*/false, Virtuality,
+      VIndex, ThisAdjustment, ContainingType, Flags, CGM.getLangOpts().Optimize,
+      TParamsArray.get());
 
   SPCache[Method->getCanonicalDecl()].reset(SP);
 
diff --git a/lib/CodeGen/MicrosoftCXXABI.cpp b/lib/CodeGen/MicrosoftCXXABI.cpp
index 31bfbf0cdf..e86d7eb773 100644
--- a/lib/CodeGen/MicrosoftCXXABI.cpp
+++ b/lib/CodeGen/MicrosoftCXXABI.cpp
@@ -551,7 +551,7 @@ private:
     return  llvm::Constant::getAllOnesValue(CGM.IntTy);
   }
 
-  CharUnits getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD);
+  CharUnits getVirtualFunctionPrologueThisAdjustment(GlobalDecl GD) override;
 
   void
   GetNullMemberPointerFields(const MemberPointerType *MPT,