Disconnects code objects from infrequently used unoptimized functions.

runtime/vm/stub_code_mips.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"
 #if defined(TARGET_ARCH_MIPS)
 
 #include "vm/assembler.h"
 #include "vm/code_generator.h"
 #include "vm/compiler.h"
@@ skipping 1794 matching lines @@
   __ AddImmediateDetectOverflow(T4, T4, Smi::RawValue(1), T5, T6);
 
   __ bgez(T5, &call_target_function);  // No overflow.
   __ delay_slot()->sw(T4, Address(T0, count_offset));
 
   __ LoadImmediate(T1, Smi::RawValue(Smi::kMaxValue));
   __ sw(T1, Address(T0, count_offset));
 
   __ Bind(&call_target_function);
   // T3: Target function.
-  __ lw(T3, FieldAddress(T3, Function::code_offset()));
-  __ lw(T3, FieldAddress(T3, Code::instructions_offset()));
+  Label is_compiled;
+  __ lw(T4, FieldAddress(T3, Function::code_offset()));
+  if (FLAG_collect_code) {
+    __ BranchNotEqual(T4, reinterpret_cast<int32_t>(Object::null()),
+                      &is_compiled);
+    __ EnterStubFrame();
+    __ addiu(SP, SP, Immediate(-3 * kWordSize));
+    __ sw(S5, Address(SP, 2 * kWordSize));  // Preserve IC data.
+    __ sw(S4, Address(SP, 1 * kWordSize));  // Preserve arg desc.
+    __ sw(T3, Address(SP, 0 * kWordSize));  // Function argument.
+    __ CallRuntime(kCompileFunctionRuntimeEntry, 1);
+    __ lw(T3, Address(SP, 0 * kWordSize));  // Restore Function.
+    __ lw(S4, Address(SP, 1 * kWordSize));  // Restore arg desc.
+    __ lw(S5, Address(SP, 2 * kWordSize));  // Restore IC data.
+    __ addiu(SP, SP, Immediate(3 * kWordSize));
+    __ LeaveStubFrame();
+    __ lw(T4, FieldAddress(T3, Function::code_offset()));
+    __ Bind(&is_compiled);
+  }
+  __ lw(T3, FieldAddress(T4, Code::instructions_offset()));
   __ AddImmediate(T3, Instructions::HeaderSize() - kHeapObjectTag);
   __ jr(T3);
 
   // Instance in T3, return its class-id in T3 as Smi.
   __ Bind(&get_class_id_as_smi);
   Label not_smi;
   // Test if Smi -> load Smi class for comparison.
   __ andi(CMPRES1, T3, Immediate(kSmiTagMask));
   __ bne(CMPRES1, ZR, &not_smi);
   __ jr(RA);
@@ skipping 569 matching lines @@
   __ lw(left, Address(SP, 1 * kWordSize));
   __ lw(temp2, Address(SP, 2 * kWordSize));
   __ lw(temp1, Address(SP, 3 * kWordSize));
   __ Ret();
   __ delay_slot()->addiu(SP, SP, Immediate(4 * kWordSize));
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS