1 files changed, 19 insertions, 0 deletions
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index 037b1351c0f..5b4017cad37 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -13,6 +13,7 @@
 
 #include "CodeGenFunction.h"
 #include "CGBlocks.h"
+#include "CGCXXABI.h"
 #include "CGCleanup.h"
 #include "CGDebugInfo.h"
 #include "CGOpenCLRuntime.h"
@@ -1769,6 +1770,24 @@ void CodeGenFunction::EmitParmDecl(const VarDecl &D, ParamValue Arg,
       setBlockContextParameter(IPD, ArgNo, Arg.getDirectValue());
       return;
     }
+
+    // Apply any prologue 'this' adjustments required by the ABI. Be careful to
+    // handle the case where 'this' is passed indirectly as part of an inalloca
+    // struct.
+    if (const CXXMethodDecl *MD =
+            dyn_cast_or_null<CXXMethodDecl>(CurCodeDecl)) {
+      if (MD->isVirtual() && IPD == CXXABIThisDecl) {
+        llvm::Value *This = Arg.isIndirect()
+                                ? Builder.CreateLoad(Arg.getIndirectAddress())
+                                : Arg.getDirectValue();
+        This = CGM.getCXXABI().adjustThisParameterInVirtualFunctionPrologue(
+            *this, CurGD, This);
+        if (Arg.isIndirect())
+          Builder.CreateStore(This, Arg.getIndirectAddress());
+        else
+          Arg = ParamValue::forDirect(This);
+      }
+    }
   }
 
   Address DeclPtr = Address::invalid();