Remove flag enable_debugger as current debugging code has a very minor influence on unoptimzied cod…

runtime/vm/stub_code_mips.cc

Index: runtime/vm/stub_code_mips.cc
===================================================================
--- runtime/vm/stub_code_mips.cc	(revision 38736)
+++ runtime/vm/stub_code_mips.cc	(working copy)
@@ -26,8 +26,6 @@
     "Set to true for debugging & verifying the slow paths.");
 DECLARE_FLAG(bool, trace_optimized_ic_calls);
 
-DECLARE_FLAG(bool, enable_debugger);
-
 // Input parameters:
 //   RA : return address.
 //   SP : address of last argument in argument array.
@@ -1405,13 +1403,11 @@
 
 
   Label stepping, done_stepping;
-  if (FLAG_enable_debugger) {
-    // Check single stepping.
-    __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
-    __ lbu(T0, Address(T0, Isolate::single_step_offset()));
-    __ BranchNotEqual(T0, 0, &stepping);
-    __ Bind(&done_stepping);
-  }
+  // Check single stepping.
+  __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
+  __ lbu(T0, Address(T0, Isolate::single_step_offset()));
+  __ BranchNotEqual(T0, 0, &stepping);
+  __ Bind(&done_stepping);
 
   // Load argument descriptor into S4.
   __ lw(S4, FieldAddress(S5, ICData::arguments_descriptor_offset()));
@@ -1546,20 +1542,18 @@
   __ AddImmediate(T4, Instructions::HeaderSize() - kHeapObjectTag);
   __ jr(T4);
 
-  if (FLAG_enable_debugger) {
-    // Call single step callback in debugger.
-    __ Bind(&stepping);
-    __ EnterStubFrame();
-    __ addiu(SP, SP, Immediate(-2 * kWordSize));
-    __ sw(S5, Address(SP, 1 * kWordSize));  // Preserve IC data.
-    __ sw(RA, Address(SP, 0 * kWordSize));  // Return address.
-    __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
-    __ lw(RA, Address(SP, 0 * kWordSize));
-    __ lw(S5, Address(SP, 1 * kWordSize));
-    __ addiu(SP, SP, Immediate(2 * kWordSize));
-    __ LeaveStubFrame();
-    __ b(&done_stepping);
-  }
+  // Call single step callback in debugger.
+  __ Bind(&stepping);
+  __ EnterStubFrame();
+  __ addiu(SP, SP, Immediate(-2 * kWordSize));
+  __ sw(S5, Address(SP, 1 * kWordSize));  // Preserve IC data.
+  __ sw(RA, Address(SP, 0 * kWordSize));  // Return address.
+  __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
+  __ lw(RA, Address(SP, 0 * kWordSize));
+  __ lw(S5, Address(SP, 1 * kWordSize));
+  __ addiu(SP, SP, Immediate(2 * kWordSize));
+  __ LeaveStubFrame();
+  __ b(&done_stepping);
 }
 
 
@@ -1643,24 +1637,22 @@
   }
 #endif  // DEBUG
 
-  if (FLAG_enable_debugger) {
-    // Check single stepping.
-    Label not_stepping;
-    __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
-    __ lbu(T0, Address(T0, Isolate::single_step_offset()));
-    __ BranchEqual(T0, 0, &not_stepping);
-    // Call single step callback in debugger.
-    __ EnterStubFrame();
-    __ addiu(SP, SP, Immediate(-2 * kWordSize));
-    __ sw(S5, Address(SP, 1 * kWordSize));  // Preserve IC data.
-    __ sw(RA, Address(SP, 0 * kWordSize));  // Return address.
-    __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
-    __ lw(RA, Address(SP, 0 * kWordSize));
-    __ lw(S5, Address(SP, 1 * kWordSize));
-    __ addiu(SP, SP, Immediate(2 * kWordSize));
-    __ LeaveStubFrame();
-    __ Bind(&not_stepping);
-  }
+  // Check single stepping.
+  Label not_stepping;
+  __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
+  __ lbu(T0, Address(T0, Isolate::single_step_offset()));
+  __ BranchEqual(T0, 0, &not_stepping);
+  // Call single step callback in debugger.
+  __ EnterStubFrame();
+  __ addiu(SP, SP, Immediate(-2 * kWordSize));
+  __ sw(S5, Address(SP, 1 * kWordSize));  // Preserve IC data.
+  __ sw(RA, Address(SP, 0 * kWordSize));  // Return address.
+  __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
+  __ lw(RA, Address(SP, 0 * kWordSize));
+  __ lw(S5, Address(SP, 1 * kWordSize));
+  __ addiu(SP, SP, Immediate(2 * kWordSize));
+  __ LeaveStubFrame();
+  __ Bind(&not_stepping);
 
   // S5: IC data object (preserved).
   __ lw(T0, FieldAddress(S5, ICData::ic_data_offset()));
@@ -1786,22 +1778,21 @@
 // Called only from unoptimized code. All relevant registers have been saved.
 // RA: return address.
 void StubCode::GenerateDebugStepCheckStub(Assembler* assembler) {
-  if (FLAG_enable_debugger) {
-    // Check single stepping.
-    Label not_stepping;
-    __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
-    __ lbu(T0, Address(T0, Isolate::single_step_offset()));
-    __ BranchEqual(T0, 0, &not_stepping);
-    // Call single step callback in debugger.
-    __ EnterStubFrame();
-    __ addiu(SP, SP, Immediate(-1 * kWordSize));
-    __ sw(RA, Address(SP, 0 * kWordSize));  // Return address.
-    __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
-    __ lw(RA, Address(SP, 0 * kWordSize));
-    __ addiu(SP, SP, Immediate(1 * kWordSize));
-    __ LeaveStubFrame();
-    __ Bind(&not_stepping);
-  }
+  // Check single stepping.
+  Label not_stepping;
+  __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
+  __ lbu(T0, Address(T0, Isolate::single_step_offset()));
+  __ BranchEqual(T0, 0, &not_stepping);
+  // Call single step callback in debugger.
+  __ EnterStubFrame();
+  __ addiu(SP, SP, Immediate(-1 * kWordSize));
+  __ sw(RA, Address(SP, 0 * kWordSize));  // Return address.
+  __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
+  __ lw(RA, Address(SP, 0 * kWordSize));
+  __ addiu(SP, SP, Immediate(1 * kWordSize));
+  __ LeaveStubFrame();
+  __ Bind(&not_stepping);
+
   __ Ret();
 }
 
@@ -2072,22 +2063,20 @@
 // Returns: CMPRES1 is zero if equal, non-zero otherwise.
 void StubCode::GenerateUnoptimizedIdenticalWithNumberCheckStub(
     Assembler* assembler) {
-  if (FLAG_enable_debugger) {
-    // Check single stepping.
-    Label not_stepping;
-    __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
-    __ lbu(T0, Address(T0, Isolate::single_step_offset()));
-    __ BranchEqual(T0, 0, &not_stepping);
-    // Call single step callback in debugger.
-    __ EnterStubFrame();
-    __ addiu(SP, SP, Immediate(-1 * kWordSize));
-    __ sw(RA, Address(SP, 0 * kWordSize));  // Return address.
-    __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
-    __ lw(RA, Address(SP, 0 * kWordSize));
-    __ addiu(SP, SP, Immediate(1 * kWordSize));
-    __ LeaveStubFrame();
-    __ Bind(&not_stepping);
-  }
+  // Check single stepping.
+  Label not_stepping;
+  __ lw(T0, FieldAddress(CTX, Context::isolate_offset()));
+  __ lbu(T0, Address(T0, Isolate::single_step_offset()));
+  __ BranchEqual(T0, 0, &not_stepping);
+  // Call single step callback in debugger.
+  __ EnterStubFrame();
+  __ addiu(SP, SP, Immediate(-1 * kWordSize));
+  __ sw(RA, Address(SP, 0 * kWordSize));  // Return address.
+  __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
+  __ lw(RA, Address(SP, 0 * kWordSize));
+  __ addiu(SP, SP, Immediate(1 * kWordSize));
+  __ LeaveStubFrame();
+  __ Bind(&not_stepping);
 
   const Register temp1 = T2;
   const Register temp2 = T3;