Fix hot reload test mode in simdbc by supporting forced slow paths on simdbc

runtime/vm/constants_dbc.h

 // Copyright (c) 2016, 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.
 
 #ifndef RUNTIME_VM_CONSTANTS_DBC_H_
 #define RUNTIME_VM_CONSTANTS_DBC_H_
 
 #include "platform/globals.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 803 matching lines @@
   V(AssertAssignable,              A_D, num, lit, ___) \
   V(AssertBoolean,                   A, num, ___, ___) \
   V(TestSmi,                       A_D, reg, reg, ___) \
   V(TestCids,                      A_D, reg, num, ___) \
   V(CheckSmi,                        A, reg, ___, ___) \
   V(CheckEitherNonSmi,             A_D, reg, reg, ___) \
   V(CheckClassId,                  A_D, reg, num, ___) \
   V(CheckDenseSwitch,              A_D, reg, num, ___) \
   V(CheckCids,                   A_B_C, reg, num, num) \
   V(CheckStack,                      0, ___, ___, ___) \
+  V(CheckStackAlwaysExit,            0, ___, ___, ___) \

[zra, 2016/12/12 22:07:37]

Maybe CheckStackAlwaysCall?

Please add docs in the comment above.

   V(DebugStep,                       0, ___, ___, ___) \
   V(DebugBreak,                      A, num, ___, ___) \
   V(Deopt,                         A_D, num, num, ___)
 
 // clang-format on
 
 typedef uint32_t Instr;
 
 class Bytecode {
  public:
@@ skipping 127 matching lines @@
 
 // After a comparison, the condition NEXT_IS_TRUE means the following
 // instruction is executed if the comparision is true and skipped over overwise.
 // Conidition NEXT_IS_FALSE means the following instruction is executed if the
 // comparison is false and skipped over otherwise.
 enum Condition { NEXT_IS_TRUE, NEXT_IS_FALSE };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_CONSTANTS_DBC_H_