[turbofan] Unify referencing of stack slots

src/x64/lithium-codegen-x64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/cpu-profiler.h"
@@ skipping 574 matching lines @@
                        value,
                        environment->HasTaggedValueAt(env_offset + i),
                        environment->HasUint32ValueAt(env_offset + i),
                        object_index_pointer,
                        dematerialized_index_pointer);
     }
     return;
   }
 
   if (op->IsStackSlot()) {
+    int index = op->index();
+    if (index >= 0) {
+      index += StandardFrameConstants::kFixedFrameSize / kPointerSize;
+    }
     if (is_tagged) {
-      translation->StoreStackSlot(op->index());
+      translation->StoreStackSlot(index);
     } else if (is_uint32) {
-      translation->StoreUint32StackSlot(op->index());
+      translation->StoreUint32StackSlot(index);
     } else {
-      translation->StoreInt32StackSlot(op->index());
+      translation->StoreInt32StackSlot(index);
     }
   } else if (op->IsDoubleStackSlot()) {
-    translation->StoreDoubleStackSlot(op->index());
+    int index = op->index();
+    if (index >= 0) {
+      index += StandardFrameConstants::kFixedFrameSize / kPointerSize;
+    }
+    translation->StoreDoubleStackSlot(index);
   } else if (op->IsRegister()) {
     Register reg = ToRegister(op);
     if (is_tagged) {
       translation->StoreRegister(reg);
     } else if (is_uint32) {
       translation->StoreUint32Register(reg);
     } else {
       translation->StoreInt32Register(reg);
     }
   } else if (op->IsDoubleRegister()) {
@@ skipping 5433 matching lines @@
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64