diff --git a/src/mips/simulator-mips.cc b/src/mips/simulator-mips.cc
index 17c1897..f31ce7e 100644
--- a/src/mips/simulator-mips.cc
+++ b/src/mips/simulator-mips.cc
@@ -72,7 +72,7 @@
 // code.
 class MipsDebugger {
  public:
-  explicit MipsDebugger(Simulator* sim);
+  explicit MipsDebugger(Simulator* sim) : sim_(sim) { }
   ~MipsDebugger();
 
   void Stop(Instruction* instr);
@@ -105,10 +105,6 @@
   void RedoBreakpoints();
 };
 
-MipsDebugger::MipsDebugger(Simulator* sim) {
-  sim_ = sim;
-}
-
 
 MipsDebugger::~MipsDebugger() {
 }
@@ -391,6 +387,13 @@
     if (line == NULL) {
       break;
     } else {
+      char* last_input = sim_->last_debugger_input();
+      if (strcmp(line, "\n") == 0 && last_input != NULL) {
+        line = last_input;
+      } else {
+        // Ownership is transferred to sim_;
+        sim_->set_last_debugger_input(line);
+      }
       // Use sscanf to parse the individual parts of the command line. At the
       // moment no command expects more than two parameters.
       int argc = SScanF(line,
@@ -757,7 +760,6 @@
         PrintF("Unknown command: %s\n", cmd);
       }
     }
-    DeleteArray(line);
   }
 
   // Add all the breakpoints back to stop execution and enter the debugger
@@ -791,6 +793,12 @@
 }
 
 
+void Simulator::set_last_debugger_input(char* input) {
+  DeleteArray(last_debugger_input_);
+  last_debugger_input_ = input;
+}
+
+
 void Simulator::FlushICache(v8::internal::HashMap* i_cache,
                             void* start_addr,
                             size_t size) {
@@ -880,7 +888,7 @@
     isolate_->set_simulator_i_cache(i_cache_);
   }
   Initialize(isolate);
-  // Setup simulator support first. Some of this information is needed to
+  // Set up simulator support first. Some of this information is needed to
   // setup the architecture state.
   stack_ = reinterpret_cast<char*>(malloc(stack_size_));
   pc_modified_ = false;
@@ -889,7 +897,7 @@
   break_pc_ = NULL;
   break_instr_ = 0;
 
-  // Setup architecture state.
+  // Set up architecture state.
   // All registers are initialized to zero to start with.
   for (int i = 0; i < kNumSimuRegisters; i++) {
     registers_[i] = 0;
@@ -911,6 +919,8 @@
   for (int i = 0; i < kNumExceptions; i++) {
     exceptions[i] = 0;
   }
+
+  last_debugger_input_ = NULL;
 }
 
 
@@ -1359,9 +1369,9 @@
 
 // Returns the limit of the stack area to enable checking for stack overflows.
 uintptr_t Simulator::StackLimit() const {
-  // Leave a safety margin of 256 bytes to prevent overrunning the stack when
+  // Leave a safety margin of 1024 bytes to prevent overrunning the stack when
   // pushing values.
-  return reinterpret_cast<uintptr_t>(stack_) + 256;
+  return reinterpret_cast<uintptr_t>(stack_) + 1024;
 }
 
 
@@ -1934,7 +1944,7 @@
   // Next pc
   int32_t next_pc = 0;
 
-  // Setup the variables if needed before executing the instruction.
+  // Set up the variables if needed before executing the instruction.
   ConfigureTypeRegister(instr,
                         alu_out,
                         i64hilo,
@@ -2281,7 +2291,7 @@
 }
 
 
-// Type 2: instructions using a 16 bytes immediate. (eg: addi, beq).
+// Type 2: instructions using a 16 bytes immediate. (e.g. addi, beq).
 void Simulator::DecodeTypeImmediate(Instruction* instr) {
   // Instruction fields.
   Opcode   op     = instr->OpcodeFieldRaw();
@@ -2604,7 +2614,7 @@
 }
 
 
-// Type 3: instructions using a 26 bytes immediate. (eg: j, jal).
+// Type 3: instructions using a 26 bytes immediate. (e.g. j, jal).
 void Simulator::DecodeTypeJump(Instruction* instr) {
   // Get current pc.
   int32_t current_pc = get_pc();
@@ -2701,7 +2711,7 @@
 int32_t Simulator::Call(byte* entry, int argument_count, ...) {
   va_list parameters;
   va_start(parameters, argument_count);
-  // Setup arguments.
+  // Set up arguments.
 
   // First four arguments passed in registers.
   ASSERT(argument_count >= 4);
@@ -2748,7 +2758,7 @@
   int32_t sp_val = get_register(sp);
   int32_t fp_val = get_register(fp);
 
-  // Setup the callee-saved registers with a known value. To be able to check
+  // Set up the callee-saved registers with a known value. To be able to check
   // that they are preserved properly across JS execution.
   int32_t callee_saved_value = icount_;
   set_register(s0, callee_saved_value);