Reapply "Inlining of static calls with trivial function bodies."

runtime/vm/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/compiler.h"
 
 #include "vm/assembler.h"
 #include "vm/ast_printer.h"
 #include "vm/code_generator.h"
 #include "vm/code_patcher.h"
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
 #include "vm/disassembler.h"
 #include "vm/exceptions.h"
 #include "vm/flags.h"
 #include "vm/flow_graph.h"
 #include "vm/flow_graph_allocator.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
+#include "vm/flow_graph_inliner.h"
 #include "vm/flow_graph_optimizer.h"
 #include "vm/il_printer.h"
 #include "vm/longjump.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/os.h"
 #include "vm/parser.h"
 #include "vm/scanner.h"
 #include "vm/symbols.h"
 #include "vm/timer.h"
 
 namespace dart {
 
 DEFINE_FLAG(bool, disassemble, false, "Disassemble dart code.");
 DEFINE_FLAG(bool, disassemble_optimized, false, "Disassemble optimized code.");
 DEFINE_FLAG(bool, trace_bailout, false, "Print bailout from ssa compiler.");
 DEFINE_FLAG(bool, trace_compiler, false, "Trace compiler operations.");
 DEFINE_FLAG(bool, cse, true, "Do common subexpression elimination.");
 DEFINE_FLAG(int, deoptimization_counter_threshold, 5,
     "How many times we allow deoptimization before we disallow"
     " certain optimizations");
+DEFINE_FLAG(bool, use_inlining, true, "Enable call-site inlining");
 DECLARE_FLAG(bool, print_flow_graph);
 
 
 // Compile a function. Should call only if the function has not been compiled.
 //   Arg0: function object.
 DEFINE_RUNTIME_ENTRY(CompileFunction, 1) {
   ASSERT(arguments.Count() == kCompileFunctionRuntimeEntry.argument_count());
   const Function& function = Function::CheckedHandle(arguments.At(0));
   ASSERT(!function.HasCode());
   const Error& error = Error::Handle(Compiler::CompileFunction(function));
@@ skipping 131 matching lines @@
         // stage.
         // Compute the use lists.
         flow_graph->ComputeUseLists();
 
         FlowGraphOptimizer optimizer(flow_graph);
         optimizer.ApplyICData();
 
         // Compute the use lists.
         flow_graph->ComputeUseLists();
 
+        // Inlining (mutates the flow graph)
+        if (FLAG_use_inlining) {
+          FlowGraphInliner inliner(flow_graph);
+          inliner.Inline();
+          // Verify that the use lists are still valid.
+          DEBUG_ASSERT(flow_graph->ValidateUseLists());
+        }
+
         // Propagate types and eliminate more type tests.
         FlowGraphTypePropagator propagator(*flow_graph);
         propagator.PropagateTypes();
 
         // Verify that the use lists are still valid.
         DEBUG_ASSERT(flow_graph->ValidateUseLists());
 
         // Do optimizations that depend on the propagated type information.
         optimizer.OptimizeComputations();
 
@@ skipping 358 matching lines @@
     result = isolate->object_store()->sticky_error();
     isolate->object_store()->clear_sticky_error();
     isolate->set_long_jump_base(base);
     return result.raw();
   }
   UNREACHABLE();
   return Object::null();
 }
 
 }  // namespace dart