VM: Fix more places with isolate embedded into unoptimized code.

runtime/vm/intermediate_language_arm.cc

 // Copyright (c) 2013, 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/globals.h"  // Needed here to get TARGET_ARCH_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/cpu.h"
@@ skipping 2901 matching lines @@
  private:
   CheckStackOverflowInstr* instruction_;
   Label osr_entry_label_;
 };
 
 
 void CheckStackOverflowInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   CheckStackOverflowSlowPath* slow_path = new CheckStackOverflowSlowPath(this);
   compiler->AddSlowPathCode(slow_path);
 
-  __ LoadImmediate(IP, Isolate::Current()->stack_limit_address());
-  __ ldr(IP, Address(IP));
+  if (compiler->is_optimizing()) {
+    __ LoadImmediate(IP, Isolate::Current()->stack_limit_address());

[Cutch, 2015/07/22 17:05:34]

We should introduce a new function:

uword AssemblerEmbeddedPointer(void* p) {
  return reinterpret_cast<uword>(p);
}

So this would become:

__ LoadImmediate(IP,
AssemblerEmbeddedPointer(Isolate::Current()->stack_limit_address()));

Later on we can put some checks inside AssemblerEmbeddedPointer to make sure
that we aren't violating any assumptions. WDYT?

+    __ ldr(IP, Address(IP));
+  } else {
+    __ LoadIsolate(IP);
+    __ ldr(IP, Address(IP, Isolate::stack_limit_offset()));
+  }
   __ cmp(SP, Operand(IP));
   __ b(slow_path->entry_label(), LS);
   if (compiler->CanOSRFunction() && in_loop()) {
     const Register temp = locs()->temp(0).reg();
     // In unoptimized code check the usage counter to trigger OSR at loop
     // stack checks.  Use progressively higher thresholds for more deeply
     // nested loops to attempt to hit outer loops with OSR when possible.
     __ LoadObject(temp, compiler->parsed_function().function());
     intptr_t threshold =
         FLAG_optimization_counter_threshold * (loop_depth() + 1);
@@ skipping 3916 matching lines @@
                                 1,
                                 locs());
   __ Drop(1);
   __ Pop(result);
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM