Merge pull request #5895 from briansull/UnboxingStub-Fix

Fix for generic unboxing stub with x8 return buffer argument

Author: briansull

src/jit/importer.cpp

@@ -5989,7 +5989,14 @@ var_types  Compiler::impImportCall(OPCODE                  opcode,
         // assume the worst-case.
         mflags  = (calliSig.callConv & CORINFO_CALLCONV_HASTHIS) ? 0 : CORINFO_FLG_STATIC;
 
-
+#ifdef DEBUG
+        if (verbose)
+        {
+            unsigned structSize = (callRetTyp == TYP_STRUCT) ? info.compCompHnd->getClassSize(calliSig.retTypeSigClass) : 0;
+            printf("\nIn Compiler::impImportCall: opcode is %s, kind=%d, callRetType is %s, structSize is %d\n", 
+                   opcodeNames[opcode], callInfo->kind, varTypeName(callRetTyp), structSize);
+        }
+#endif
         //This should be checked in impImportBlockCode.
         assert(!compIsForInlining()
                || !(impInlineInfo->inlineCandidateInfo->dwRestrictions & INLINE_RESPECT_BOUNDARY));
@@ -6021,6 +6028,14 @@ var_types  Compiler::impImportCall(OPCODE                  opcode,
 
         mflags   = callInfo->methodFlags;
 
+#ifdef DEBUG
+        if (verbose)
+        {
+            unsigned structSize = (callRetTyp == TYP_STRUCT) ? info.compCompHnd->getClassSize(sig->retTypeSigClass) : 0;
+            printf("\nIn Compiler::impImportCall: opcode is %s, kind=%d, callRetType is %s, structSize is %d\n", 
+                   opcodeNames[opcode], callInfo->kind, varTypeName(callRetTyp), structSize);
+        }
+#endif
         if (compIsForInlining())
         {
             /* Does this call site have security boundary restrictions? */

src/jit/morph.cpp

@@ -3683,24 +3683,6 @@ GenTreeCall* Compiler::fgMorphArgs(GenTreeCall* callNode)
             assert(size == 1);
 #endif
 #endif
-            // If 'expectRetBuffArg' is true then the next argument is the RetBufArg
-            // and we may need to change nextRegNum to the theFixedRetBuffReg
-            //
-            if (expectRetBuffArg)
-            {
-                assert(passUsingFloatRegs == false);
-              
-                if (hasFixedRetBuffReg())
-                {
-                    // Change the register used to pass the next argument to the fixed return buffer register
-                    nextRegNum = theFixedRetBuffReg();
-                    // Note that later in this method we don't increment intArgRegNum when we 
-                    // have setup nextRegRun to be the fixed retrurn buffer register
-                }
-
-                // We no longer are expecting the RetBufArg
-                expectRetBuffArg = false;
-            }
 
 #ifndef LEGACY_BACKEND
             // If there are nonstandard args (outside the calling convention) they were inserted above
@@ -3735,6 +3717,25 @@ GenTreeCall* Compiler::fgMorphArgs(GenTreeCall* callNode)
                 continue;
 #endif // !LEGACY_BACKEND
 
+            // If 'expectRetBuffArg' is true then the next argument is the RetBufArg
+            // and we may need to change nextRegNum to the theFixedRetBuffReg
+            //
+            if (expectRetBuffArg)
+            {
+                assert(passUsingFloatRegs == false);
+
+                if (hasFixedRetBuffReg())
+                {
+                    // Change the register used to pass the next argument to the fixed return buffer register
+                    nextRegNum = theFixedRetBuffReg();
+                    // Note that later in this method we don't increment intArgRegNum when we 
+                    // have setup nextRegRun to be the fixed retrurn buffer register
+                }
+
+                // We no longer are expecting the RetBufArg
+                expectRetBuffArg = false;
+            }
+
             if (!lateArgsComputed)
             {
                 // This is a register argument - put it in the table