fix r2r relative indirection for arm.

Author: Sergey Andreenko

src/jit/lower.cpp

@@ -3173,13 +3173,48 @@ GenTree* Lowering::LowerDirectCall(GenTreeCall* call)
 
 #ifdef FEATURE_READYTORUN_COMPILER
 #if defined(_TARGET_ARMARCH_)
-            // For arm64, we dispatch code same as VSD using X11 for indirection cell address,
+            // For arm, we dispatch code same as VSD using X11 for indirection cell address,
             // which ZapIndirectHelperThunk expects.
             if (call->IsR2RRelativeIndir())
             {
                 cellAddr->gtRegNum = REG_R2R_INDIRECT_PARAM;
                 indir->gtRegNum    = REG_JUMP_THUNK_PARAM;
+
+                GenTreeIntCon* indirectCellAddress = nullptr;
+
+                for (GenTreeArgList* args = call->gtCallArgs; args; args = args->Rest())
+                {
+                    GenTree* arg = args->Current();
+                    if (arg->gtRegNum == REG_R2R_INDIRECT_PARAM)
+                    {
+                        GenTree* putArgValue = arg->AsOp()->gtOp.gtOp1;
+                        if (putArgValue->IsIconHandle(GTF_ICON_FTN_ADDR))
+                        {
+                            assert(indirectCellAddress == nullptr);
+                            indirectCellAddress = putArgValue->AsIntCon();
+                        }
+                    }
+                }
+
+                for (GenTreeArgList* args = call->gtCallLateArgs; args; args = args->Rest())
+                {
+                    GenTree* arg = args->Current();
+                    if (arg->gtRegNum == REG_R2R_INDIRECT_PARAM)
+                    {
+                        GenTree* putArgValue = arg->AsOp()->gtOp.gtOp1;
+                        if (putArgValue->IsIconHandle(GTF_ICON_FTN_ADDR))
+                        {
+                            assert(indirectCellAddress == nullptr);
+                            indirectCellAddress = putArgValue->AsIntCon();
+                        }
+                    }
+                }
+                assert(indirectCellAddress != nullptr);
+                indirectCellAddress->gtIconVal = (size_t)addr;
             }
+#else
+// x64/x86 uses an encoding trick - it assumes the call is dispatched like call[addr],
+// do not need to do anything for them.
 #endif
 #endif
             result = indir;

src/jit/morph.cpp

@@ -3134,6 +3134,24 @@ GenTreeCall* Compiler::fgMorphArgs(GenTreeCall* call)
             call->gtCallType    = CT_HELPER;
             call->gtCallMethHnd = eeFindHelper(CORINFO_HELP_PINVOKE_CALLI);
         }
+#ifdef FEATURE_READYTORUN_COMPILER
+#ifdef _TARGET_ARMARCH_
+        // For arm, we dispatch code same as VSD using virtualStubParamInfo->GetReg()
+        // for indirection cell address, which ZapIndirectHelperThunk expects.
+        if (call->IsR2RRelativeIndir())
+        {
+            // Create a placeholder for the real value, that will be added in lower.
+            GenTree* indirectCellAddress  = gtNewIconHandleNode(0, GTF_ICON_FTN_ADDR);
+            indirectCellAddress->gtRegNum = REG_R2R_INDIRECT_PARAM;
+            // And push the stub address onto the list of arguments
+            call->gtCallArgs = gtNewListNode(indirectCellAddress, call->gtCallArgs);
+
+            numArgs++;
+            nonStandardArgs.Add(indirectCellAddress, indirectCellAddress->gtRegNum);
+        }
+
+#endif // _TARGET_ARMARCH_
+#endif // FEATURE_READYTORUN_COMPILER
 #endif // !defined(LEGACY_BACKEND)
 
         // Allocate the fgArgInfo for the call node;
@@ -8099,6 +8117,10 @@ GenTree* Compiler::fgGetStubAddrArg(GenTreeCall* call)
     }
     assert(stubAddrArg != nullptr);
     stubAddrArg->gtRegNum = virtualStubParamInfo->GetReg();
+    if (verbose)
+    {
+        printf("fgGetStubAddrArg for call %d : %d\n", call->gtTreeID, stubAddrArg->gtTreeID);
+    }
     return stubAddrArg;
 }
 

src/jit/rationalize.cpp

@@ -160,14 +160,14 @@ void Rationalizer::RewriteNodeAsCall(GenTree**             use,
     assert(JITtype2varType(sig.retType) == tree->gtType);
 #endif // DEBUG
 
-    call = comp->fgMorphArgs(call);
-    // Determine if this call has changed any codegen requirements.
-    comp->fgCheckArgCnt();
-
 #ifdef FEATURE_READYTORUN_COMPILER
     call->gtCall.setEntryPoint(entryPoint);
 #endif
 
+    call = comp->fgMorphArgs(call);
+    // Determine if this call has changed any codegen requirements.
+    comp->fgCheckArgCnt();
+
     // Replace "tree" with "call"
     if (parents.Height() > 1)
     {