From c3a7ed0dcc7a58eaaaee2fa5d5900bb0efb4694a Mon Sep 17 00:00:00 2001
From: Mike McLaughlin <mikem@microsoft.com>
Date: Tue, 13 Sep 2016 05:48:27 -0700
Subject: [PATCH] Fix funceval for enregistered value types arguments. (#7149)

Issue #7115.

MethodDescCallSide.CallTargetWorker used by funceval needed to deal with
enregistered 16 byte value types arguments not just return values.
---
 src/vm/callhelpers.cpp | 88 ++++++++++++++++++++++++++++----------------------
 1 file changed, 50 insertions(+), 38 deletions(-)

diff --git a/src/vm/callhelpers.cpp b/src/vm/callhelpers.cpp
index 9152f71..addd519 100644
--- a/src/vm/callhelpers.cpp
+++ b/src/vm/callhelpers.cpp
@@ -16,6 +16,8 @@
 // To include declaration of "SignatureNative"
 #include "runtimehandles.h"
 
+#include "invokeutil.h"
+#include "argdestination.h"
 
 #if defined(FEATURE_MULTICOREJIT) && defined(_DEBUG)
 
@@ -536,7 +538,7 @@ void MethodDescCallSite::CallTargetWorker(const ARG_SLOT *pArguments, ARG_SLOT *
         }
 #endif
 
-        int    ofs;
+        int ofs;
         for (; TransitionBlock::InvalidOffset != (ofs = m_argIt.GetNextOffset()); arg++)
         {
 #ifdef CALLDESCR_REGTYPEMAP
@@ -567,46 +569,56 @@ void MethodDescCallSite::CallTargetWorker(const ARG_SLOT *pArguments, ARG_SLOT *
             }
 #endif // CHECK_APP_DOMAIN_LEAKS
 
-#if defined(UNIX_AMD64_ABI) && defined(FEATURE_UNIX_AMD64_STRUCT_PASSING)
-            _ASSERTE(ofs != TransitionBlock::StructInRegsOffset);
-#endif
-            PVOID pDest = pTransitionBlock + ofs;
+            ArgDestination argDest(pTransitionBlock, ofs, m_argIt.GetArgLocDescForStructInRegs());
 
             UINT32 stackSize = m_argIt.GetArgSize();
-            switch (stackSize)
+            // We need to pass in a pointer, but be careful of the ARG_SLOT calling convention. We might already have a pointer in the ARG_SLOT.
+            PVOID pSrc = stackSize > sizeof(ARG_SLOT) ? (LPVOID)ArgSlotToPtr(pArguments[arg]) : (LPVOID)ArgSlotEndianessFixup((ARG_SLOT*)&pArguments[arg], stackSize);
+
+#if defined(UNIX_AMD64_ABI) && defined(FEATURE_UNIX_AMD64_STRUCT_PASSING)
+            if (argDest.IsStructPassedInRegs())
+            {
+                TypeHandle th;
+                m_argIt.GetArgType(&th);
+
+                argDest.CopyStructToRegisters(pSrc, th.AsMethodTable()->GetNumInstanceFieldBytes(), 0);
+            }
+            else
+#endif // UNIX_AMD64_ABI && FEATURE_UNIX_AMD64_STRUCT_PASSING
             {
-                case 1:
-                case 2:
-                case 4:
-                    *((INT32*)pDest) = (INT32)pArguments[arg];
-                    break;
-
-                case 8:
-                    *((INT64*)pDest) = pArguments[arg];
-                    break;
-
-                default:
-                    // The ARG_SLOT contains a pointer to the value-type
-#ifdef ENREGISTERED_PARAMTYPE_MAXSIZE
-                    if (m_argIt.IsArgPassedByRef())
-                    {
-                        // We need to pass in a pointer, but be careful of the ARG_SLOT calling convention.
-                        // We might already have a pointer in the ARG_SLOT
-                       *(PVOID*)pDest = stackSize>sizeof(ARG_SLOT) ?
-                                (LPVOID)ArgSlotToPtr(pArguments[arg]) :
-                                (LPVOID)ArgSlotEndianessFixup((ARG_SLOT*)&pArguments[arg], stackSize);
-                    }
-                    else
-#endif // ENREGISTERED_PARAMTYPE_MAXSIZE
-                    if (stackSize>sizeof(ARG_SLOT))
-                    {
-                        CopyMemory(pDest, ArgSlotToPtr(pArguments[arg]), stackSize);
-                    }
-                    else
-                    {
-                        CopyMemory(pDest, (LPVOID) (&pArguments[arg]), stackSize);
-                    }
-                    break;
+                PVOID pDest = argDest.GetDestinationAddress();
+
+                switch (stackSize)
+                {
+                    case 1:
+                    case 2:
+                    case 4:
+                        *((INT32*)pDest) = (INT32)pArguments[arg];
+                        break;
+
+                    case 8:
+                        *((INT64*)pDest) = pArguments[arg];
+                        break;
+
+                    default:
+                        // The ARG_SLOT contains a pointer to the value-type
+    #ifdef ENREGISTERED_PARAMTYPE_MAXSIZE
+                        if (m_argIt.IsArgPassedByRef())
+                        {
+                            *(PVOID*)pDest = pSrc;
+                        }
+                        else
+    #endif // ENREGISTERED_PARAMTYPE_MAXSIZE
+                        if (stackSize > sizeof(ARG_SLOT))
+                        {
+                            CopyMemory(pDest, ArgSlotToPtr(pArguments[arg]), stackSize);
+                        }
+                        else
+                        {
+                            CopyMemory(pDest, (LPVOID) (&pArguments[arg]), stackSize);
+                        }
+                        break;
+                }
             }
         }
 
-- 
2.7.4