VM: Add smi fast path operations for precompiled code

runtime/vm/stack_frame.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/stack_frame.h"
 
 #include "platform/memory_sanitizer.h"
 #include "vm/assembler.h"
 #include "vm/deopt_instructions.h"
 #include "vm/isolate.h"
@@ skipping 94 matching lines @@
     map = code.GetStackmap(pc() - entry, &maps, &map);
     if (!map.IsNull()) {
       RawObject** first = reinterpret_cast<RawObject**>(sp());
       RawObject** last = reinterpret_cast<RawObject**>(
           fp() + (kFirstLocalSlotFromFp * kWordSize));
 
       // A stack map is present in the code object, use the stack map to
       // visit frame slots which are marked as having objects.
       //
       // The layout of the frame is (lower addresses to the right):
-      // | spill slots | outgoing arguments | saved registers |
-      // |XXXXXXXXXXXXX|--------------------|XXXXXXXXXXXXXXXXX|
+      // | spill slots | outgoing arguments | saved registers | slow-path args |
+      // |XXXXXXXXXXXXX|--------------------|XXXXXXXXXXXXXXXXX|XXXXXXXXXXXXXXXX|
       //
       // The spill slots and any saved registers are described in the stack
       // map.  The outgoing arguments are assumed to be tagged; the number
       // of outgoing arguments is not explicitly tracked.
-      //
-      // TODO(kmillikin): This does not handle slow path calls with
-      // arguments, where the arguments are pushed after the live registers.
-      // Enable such calls.
       intptr_t length = map.Length();
       // Spill slots are at the 'bottom' of the frame.
-      intptr_t spill_slot_count = length - map.RegisterBitCount();
+      intptr_t spill_slot_count = length - map.SlowPathBitCount();
       for (intptr_t bit = 0; bit < spill_slot_count; ++bit) {
         if (map.IsObject(bit)) {
           visitor->VisitPointer(last);
         }
         --last;
       }
 
       // The live registers at the 'top' of the frame comprise the rest of the
       // stack map.
       for (intptr_t bit = length - 1; bit >= spill_slot_count; --bit) {
@@ skipping 356 matching lines @@
     if (deopt_instr->kind() == DeoptInstr::kCallerFp) {
       return (index - num_materializations_);
     }
   }
   UNREACHABLE();
   return 0;
 }
 
 
 }  // namespace dart