Introduce intrinsic to expose debug state to generated code.

src/arm/full-codegen-arm.cc

 // Copyright 2012 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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM
 
 #include "src/code-stubs.h"
 #include "src/codegen.h"
@@ skipping 4010 matching lines @@
   ASSERT(result.is(r0));
   __ b(&done);
 
   __ bind(&bailout);
   __ LoadRoot(r0, Heap::kUndefinedValueRootIndex);
   __ bind(&done);
   context()->Plug(r0);
 }
 
 
+void FullCodeGenerator::EmitDebugIsActive(CallRuntime* expr) {
+  ASSERT(expr->arguments()->length() == 0);
+  ExternalReference debug_is_active =
+      ExternalReference::debug_is_active_address(isolate());
+  __ mov(ip, Operand(debug_is_active));
+  __ ldrb(r0, MemOperand(ip));
+  __ SmiTag(r0);
+  context()->Plug(r0);
+}
+
+
 void FullCodeGenerator::VisitCallRuntime(CallRuntime* expr) {
   if (expr->function() != NULL &&
       expr->function()->intrinsic_type == Runtime::INLINE) {
     Comment cmnt(masm_, "[ InlineRuntimeCall");
     EmitInlineRuntimeCall(expr);
     return;
   }
 
   Comment cmnt(masm_, "[ CallRuntime");
   ZoneList<Expression*>* args = expr->arguments();
@@ skipping 790 matching lines @@
 
   ASSERT(interrupt_address ==
          isolate->builtins()->OsrAfterStackCheck()->entry());
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM