Introduce a lazy-compile stub for functions.

runtime/vm/stub_code_ia32.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_IA32)
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
@@ skipping 755 matching lines @@
   __ j(ZERO, &not_closure, Assembler::kNearJump);  // Not a closure, but a smi.
   // Verify that the class of the object is a closure class by checking that
   // class.signature_function() is not null.
   __ LoadClass(EAX, EDI, ECX);
   __ movl(EAX, FieldAddress(EAX, Class::signature_function_offset()));
   __ cmpl(EAX, raw_null);
   // Actual class is not a closure class.
   __ j(EQUAL, &not_closure, Assembler::kNearJump);
 
   // EAX is just the signature function. Load the actual closure function.
-  __ movl(ECX, FieldAddress(EDI, Closure::function_offset()));
+  __ movl(EAX, FieldAddress(EDI, Closure::function_offset()));
 
   // Load closure context in CTX; note that CTX has already been preserved.
   __ movl(CTX, FieldAddress(EDI, Closure::context_offset()));
 
-  // Load closure function code in EAX.
-  __ movl(EAX, FieldAddress(ECX, Function::code_offset()));
-  __ cmpl(EAX, raw_null);
-  Label function_compiled;
-  __ j(NOT_EQUAL, &function_compiled, Assembler::kNearJump);
+  // EBX: Code (compiled code or lazy compile stub).
+  __ movl(EBX, FieldAddress(EAX, Function::code_offset()));
 
-  // Create a stub frame as we are pushing some objects on the stack before
-  // calling into the runtime.
-  __ EnterStubFrame();
-
-  __ pushl(EDX);  // Preserve arguments descriptor array.
-  __ pushl(ECX);  // Preserve read-only function object argument.
-  __ CallRuntime(kCompileFunctionRuntimeEntry, 1);
-  __ popl(ECX);  // Restore read-only function object argument in ECX.
-  __ popl(EDX);  // Restore arguments descriptor array.
-  // Restore EAX.
-  __ movl(EAX, FieldAddress(ECX, Function::code_offset()));
-
-  // Remove the stub frame as we are about to jump to the closure function.
-  __ LeaveFrame();
-
-  __ Bind(&function_compiled);
-  // EAX: Code.
-  // ECX: Function.
+  // EAX: Function.
   // EDX: Arguments descriptor array.
-
-  __ movl(ECX, FieldAddress(EAX, Code::instructions_offset()));
+  __ movl(ECX, FieldAddress(EBX, Code::instructions_offset()));
   __ addl(ECX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
   __ jmp(ECX);
 
   __ Bind(&not_closure);
   // Call runtime to attempt to resolve and invoke a call method on a
   // non-closure object, passing the non-closure object and its arguments array,
   // returning here.
   // If no call method exists, throw a NoSuchMethodError.
   // EDI: non-closure object.
   // EDX: arguments descriptor array.
@@ skipping 683 matching lines @@
   const intptr_t target_offset = ICData::TargetIndexFor(num_args) * kWordSize;
   const intptr_t count_offset = ICData::CountIndexFor(num_args) * kWordSize;
   __ movl(EAX, Address(EBX, target_offset));
   __ addl(Address(EBX, count_offset), Immediate(Smi::RawValue(1)));
   __ j(NO_OVERFLOW, &call_target_function, Assembler::kNearJump);
   __ movl(Address(EBX, count_offset),
           Immediate(Smi::RawValue(Smi::kMaxValue)));
 
   __ Bind(&call_target_function);
   // EAX: Target function.
-  Label is_compiled;
   __ movl(EBX, FieldAddress(EAX, Function::code_offset()));
-  if (FLAG_collect_code) {
-    // If code might be GC'd, then EBX might be null. If it is, recompile.
-    __ cmpl(EBX, raw_null);
-    __ j(NOT_EQUAL, &is_compiled, Assembler::kNearJump);
-    __ EnterStubFrame();
-    __ pushl(EDX);  // Preserve arguments descriptor array.
-    __ pushl(ECX);  // Preserve IC data object.
-    __ pushl(EAX);  // Pass function.
-    __ CallRuntime(kCompileFunctionRuntimeEntry, 1);
-    __ popl(EAX);  // Restore function.
-    __ popl(ECX);  // Restore IC data array.
-    __ popl(EDX);  // Restore arguments descriptor array.
-    __ LeaveFrame();
-    __ movl(EBX, FieldAddress(EAX, Function::code_offset()));
-    __ Bind(&is_compiled);
-  }
-  __ movl(EAX, FieldAddress(EBX, Code::instructions_offset()));
-  __ addl(EAX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
-  __ jmp(EAX);
+  __ movl(EBX, FieldAddress(EBX, Code::instructions_offset()));
+  __ addl(EBX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ jmp(EBX);
 
   // Instance in EAX, return its class-id in EAX as Smi.
   __ Bind(&get_class_id_as_smi);
   Label not_smi;
   // Test if Smi -> load Smi class for comparison.
   __ testl(EAX, Immediate(kSmiTagMask));
   __ j(NOT_ZERO, &not_smi, Assembler::kNearJump);
   __ movl(EAX, Immediate(Smi::RawValue(kSmiCid)));
   __ ret();
 
@@ skipping 123 matching lines @@
   const intptr_t target_offset = ICData::TargetIndexFor(0) * kWordSize;
   const intptr_t count_offset = ICData::CountIndexFor(0) * kWordSize;
 
   // Increment count for this call.
   Label increment_done;
   __ addl(Address(EBX, count_offset), Immediate(Smi::RawValue(1)));
   __ j(NO_OVERFLOW, &increment_done, Assembler::kNearJump);
   __ movl(Address(EBX, count_offset), Immediate(Smi::RawValue(Smi::kMaxValue)));
   __ Bind(&increment_done);
 
-  const Immediate& raw_null =
-      Immediate(reinterpret_cast<intptr_t>(Object::null()));
-  Label target_is_compiled;
-  // Get function and call it, if possible.
-  __ movl(EDI, Address(EBX, target_offset));
-  __ movl(EAX, FieldAddress(EDI, Function::code_offset()));
-  __ cmpl(EAX, raw_null);
-  __ j(NOT_EQUAL, &target_is_compiled, Assembler::kNearJump);
-  __ EnterStubFrame();
-  __ pushl(EDI);  // Preserve target function.
-  __ pushl(ECX);  // Preserve IC data object.
-  __ pushl(EDI);  // Pass function.
-  __ CallRuntime(kCompileFunctionRuntimeEntry, 1);
-  __ popl(EAX);  // Discard argument.
-  __ popl(ECX);  // Restore IC data object.
-  __ popl(EDI);  // Restore target function.
-  __ LeaveFrame();
-  __ movl(EAX, FieldAddress(EDI, Function::code_offset()));
-
-  __ Bind(&target_is_compiled);
-  // EAX: Target code.
-  __ movl(EAX, FieldAddress(EAX, Code::instructions_offset()));
-  __ addl(EAX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
   // Load arguments descriptor into EDX.
   __ movl(EDX, FieldAddress(ECX, ICData::arguments_descriptor_offset()));
-  __ jmp(EAX);
+
+  // Get function and call it, if possible.
+  __ movl(EAX, Address(EBX, target_offset));
+  __ movl(EBX, FieldAddress(EAX, Function::code_offset()));
+
+  // EBX: Target code.
+  __ movl(EBX, FieldAddress(EBX, Code::instructions_offset()));
+  __ addl(EBX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ jmp(EBX);
 }
 
 
 void StubCode::GenerateTwoArgsUnoptimizedStaticCallStub(Assembler* assembler) {
   GenerateUsageCounterIncrement(assembler, EBX);
   GenerateNArgsCheckInlineCacheStub(
       assembler, 2, kStaticCallMissHandlerTwoArgsRuntimeEntry);
 }
 
 
-// Stub for calling the CompileFunction runtime call.
-// ECX: IC-Data.
+// Stub for compiling a function and jumping to the compiled code.
+// ECX: IC-Data (for methods).
 // EDX: Arguments descriptor.
 // EAX: Function.
-void StubCode::GenerateCompileFunctionRuntimeCallStub(Assembler* assembler) {
+void StubCode::GenerateLazyCompileStub(Assembler* assembler) {
   __ EnterStubFrame();
   __ pushl(EDX);  // Preserve arguments descriptor array.
   __ pushl(ECX);  // Preserve IC data object.
   __ pushl(EAX);  // Pass function.
   __ CallRuntime(kCompileFunctionRuntimeEntry, 1);
   __ popl(EAX);  // Restore function.
   __ popl(ECX);  // Restore IC data array.
   __ popl(EDX);  // Restore arguments descriptor array.
   __ LeaveFrame();
-  __ ret();
+
+  __ movl(EAX, FieldAddress(EAX, Function::code_offset()));
+  __ movl(EAX, FieldAddress(EAX, Code::instructions_offset()));
+  __ addl(EAX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ jmp(EAX);
 }
 
 
 // EDX, ECX: May contain arguments to runtime stub.
 void StubCode::GenerateBreakpointRuntimeStub(Assembler* assembler) {
   __ EnterStubFrame();
   // Save runtime args.
   __ pushl(ECX);
   __ pushl(EDX);
   // Room for result. Debugger stub returns address of the
@@ skipping 299 matching lines @@
   const Register temp = ECX;
   __ movl(left, Address(ESP, 2 * kWordSize));
   __ movl(right, Address(ESP, 1 * kWordSize));
   GenerateIdenticalWithNumberCheckStub(assembler, left, right, temp);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32