Add asserts to ensure that we:

src/arm/debug-arm.cc

Index: src/arm/debug-arm.cc
===================================================================
--- src/arm/debug-arm.cc	(revision 9277)
+++ src/arm/debug-arm.cc	(working copy)
@@ -132,56 +132,58 @@
 static void Generate_DebugBreakCallHelper(MacroAssembler* masm,
                                           RegList object_regs,
                                           RegList non_object_regs) {
-  __ EnterInternalFrame();
+  {
+    FrameScope scope(masm, StackFrame::INTERNAL);
 
-  // Store the registers containing live values on the expression stack to
-  // make sure that these are correctly updated during GC. Non object values
-  // are stored as a smi causing it to be untouched by GC.
-  ASSERT((object_regs & ~kJSCallerSaved) == 0);
-  ASSERT((non_object_regs & ~kJSCallerSaved) == 0);
-  ASSERT((object_regs & non_object_regs) == 0);
-  if ((object_regs | non_object_regs) != 0) {
-    for (int i = 0; i < kNumJSCallerSaved; i++) {
-      int r = JSCallerSavedCode(i);
-      Register reg = { r };
-      if ((non_object_regs & (1 << r)) != 0) {
-        if (FLAG_debug_code) {
-          __ tst(reg, Operand(0xc0000000));
-          __ Assert(eq, "Unable to encode value as smi");
+    // Store the registers containing live values on the expression stack to
+    // make sure that these are correctly updated during GC. Non object values
+    // are stored as a smi causing it to be untouched by GC.
+    ASSERT((object_regs & ~kJSCallerSaved) == 0);
+    ASSERT((non_object_regs & ~kJSCallerSaved) == 0);
+    ASSERT((object_regs & non_object_regs) == 0);
+    if ((object_regs | non_object_regs) != 0) {
+      for (int i = 0; i < kNumJSCallerSaved; i++) {
+        int r = JSCallerSavedCode(i);
+        Register reg = { r };
+        if ((non_object_regs & (1 << r)) != 0) {
+          if (FLAG_debug_code) {
+            __ tst(reg, Operand(0xc0000000));
+            __ Assert(eq, "Unable to encode value as smi");
+          }
+          __ mov(reg, Operand(reg, LSL, kSmiTagSize));
         }
-        __ mov(reg, Operand(reg, LSL, kSmiTagSize));
       }
+      __ stm(db_w, sp, object_regs | non_object_regs);
     }
-    __ stm(db_w, sp, object_regs | non_object_regs);
-  }
 
 #ifdef DEBUG
-  __ RecordComment("// Calling from debug break to runtime - come in - over");
+    __ RecordComment("// Calling from debug break to runtime - come in - over");
 #endif
-  __ mov(r0, Operand(0, RelocInfo::NONE));  // no arguments
-  __ mov(r1, Operand(ExternalReference::debug_break(masm->isolate())));
+    __ mov(r0, Operand(0, RelocInfo::NONE));  // no arguments
+    __ mov(r1, Operand(ExternalReference::debug_break(masm->isolate())));
 
-  CEntryStub ceb(1);
-  __ CallStub(&ceb);
+    CEntryStub ceb(1);
+    __ CallStub(&ceb);
 
-  // Restore the register values from the expression stack.
-  if ((object_regs | non_object_regs) != 0) {
-    __ ldm(ia_w, sp, object_regs | non_object_regs);
-    for (int i = 0; i < kNumJSCallerSaved; i++) {
-      int r = JSCallerSavedCode(i);
-      Register reg = { r };
-      if ((non_object_regs & (1 << r)) != 0) {
-        __ mov(reg, Operand(reg, LSR, kSmiTagSize));
+    // Restore the register values from the expression stack.
+    if ((object_regs | non_object_regs) != 0) {
+      __ ldm(ia_w, sp, object_regs | non_object_regs);
+      for (int i = 0; i < kNumJSCallerSaved; i++) {
+        int r = JSCallerSavedCode(i);
+        Register reg = { r };
+        if ((non_object_regs & (1 << r)) != 0) {
+          __ mov(reg, Operand(reg, LSR, kSmiTagSize));
+        }
+        if (FLAG_debug_code &&
+            (((object_regs |non_object_regs) & (1 << r)) == 0)) {
+          __ mov(reg, Operand(kDebugZapValue));
+        }
       }
-      if (FLAG_debug_code &&
-          (((object_regs |non_object_regs) & (1 << r)) == 0)) {
-        __ mov(reg, Operand(kDebugZapValue));
-      }
     }
+
+    // Leave the internal frame.
   }
 
-  __ LeaveInternalFrame();
-
   // Now that the break point has been handled, resume normal execution by
   // jumping to the target address intended by the caller and that was
   // overwritten by the address of DebugBreakXXX.