Minor cleanups: use GrowableArray::is_empty instead of ::length() == 0

runtime/vm/flow_graph_compiler.cc

 // Copyright (c) 2012, 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"  // Needed here to get TARGET_ARCH_XXX.
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
@@ skipping 493 matching lines @@
     if (!blocked_registers[regno] && (registers_[regno] == NULL)) {
       blocked_registers[regno] = true;
       return static_cast<Register>(regno);
     }
   }
   return SpillFirst();
 }
 
 
 Register FrameRegisterAllocator::SpillFirst() {
-  ASSERT(stack_.length() > 0);
+  ASSERT(!stack_.is_empty());
   Register reg = stack_[0];
   stack_.RemoveFirst();
   compiler()->assembler()->PushRegister(reg);
   registers_[reg] = NULL;
   return reg;
 }
 
 
 void FrameRegisterAllocator::SpillRegister(Register reg) {
   while (registers_[reg] != NULL) SpillFirst();
@@ skipping 57 matching lines @@
   }
 
   // Allocate all unallocated input locations.
   for (intptr_t i = locs->input_count() - 1; i >= 0; i--) {
     Location loc = locs->in(i);
     Register reg = kNoRegister;
     if (loc.IsRegister()) {
       reg = loc.reg();
     } else if (loc.IsUnallocated()) {
       ASSERT(loc.policy() == Location::kRequiresRegister);
-      if ((stack_.length() > 0) && !blocked_temp_registers[stack_.Last()]) {
+      if (!stack_.is_empty() && !blocked_temp_registers[stack_.Last()]) {
         reg = stack_.Last();
         blocked_registers[reg] = true;
       } else {
         reg = AllocateFreeRegister(blocked_registers);
       }
       locs->set_in(i, Location::RegisterLocation(reg));
     }
 
     Pop(reg, instr->InputAt(i));
   }
@@ skipping 32 matching lines @@
 
   if (result_location.IsRegister()) {
     SpillRegister(result_location.reg());
   }
 }
 
 
 void FrameRegisterAllocator::Pop(Register dst, Value* val) {
   if (is_ssa_) return;
 
-  if (stack_.length() > 0) {
+  if (!stack_.is_empty()) {
     ASSERT(keep_values_in_registers_);
     Register src = stack_.Last();
     ASSERT(val->AsUse()->definition() == registers_[src]);
     stack_.RemoveLast();
     registers_[src] = NULL;
     compiler()->assembler()->MoveRegister(dst, src);
   } else {
     compiler()->assembler()->PopRegister(dst);
   }
 }
@@ skipping 135 matching lines @@
       return;
     }
   }
 
   // This move is not blocked.
   EmitMove(index);
 }
 
 
 }  // namespace dart