Pass closure object as first implicit argument to closure functions.

runtime/vm/stub_code_ia32.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"
 #if defined(TARGET_ARCH_IA32)
 
 #include "vm/assembler.h"
 #include "vm/assembler_macros.h"
 #include "vm/compiler.h"
@@ skipping 18 matching lines @@
 // Input parameters:
 //   ESP : points to return address.
 //   ESP + 4 : address of last argument in argument array.
 //   ESP + 4*EDX : address of first argument in argument array.
 //   ESP + 4*EDX + 4 : address of return value.
 //   ECX : address of the runtime function to call.
 //   EDX : number of arguments to the call.
 // Must preserve callee saved registers EDI and EBX.
 void StubCode::GenerateCallToRuntimeStub(Assembler* assembler) {
   const intptr_t isolate_offset = NativeArguments::isolate_offset();
-  const intptr_t argc_offset = NativeArguments::argc_offset();
+  const intptr_t argc_tag_offset = NativeArguments::argc_tag_offset();
   const intptr_t argv_offset = NativeArguments::argv_offset();
   const intptr_t retval_offset = NativeArguments::retval_offset();
 
   __ EnterFrame(0);
 
   // Load current Isolate pointer from Context structure into EAX.
   __ movl(EAX, FieldAddress(CTX, Context::isolate_offset()));
 
   // Save exit frame information to enable stack walking as we are about
   // to transition to Dart VM C++ code.
   __ movl(Address(EAX, Isolate::top_exit_frame_info_offset()), ESP);
 
   // Save current Context pointer into Isolate structure.
   __ movl(Address(EAX, Isolate::top_context_offset()), CTX);
 
   // Cache Isolate pointer into CTX while executing runtime code.
   __ movl(CTX, EAX);
 
   // Reserve space for arguments and align frame before entering C++ world.
   __ AddImmediate(ESP, Immediate(-sizeof(NativeArguments)));
   if (OS::ActivationFrameAlignment() > 0) {
     __ andl(ESP, Immediate(~(OS::ActivationFrameAlignment() - 1)));
   }
 
   // Pass NativeArguments structure by value and call runtime.
   __ movl(Address(ESP, isolate_offset), CTX);  // Set isolate in NativeArgs.
-  __ movl(Address(ESP, argc_offset), EDX);  // Set argc in NativeArguments.
+  // There are no runtime calls to closures, so we do not need to set the tag
+  // bits kClosureFunctionBit and kInstanceFunctionBit in argc_tag_.
+  __ movl(Address(ESP, argc_tag_offset), EDX);  // Set argc in NativeArguments.
   __ leal(EAX, Address(EBP, EDX, TIMES_4, 1 * kWordSize));  // Compute argv.
   __ movl(Address(ESP, argv_offset), EAX);  // Set argv in NativeArguments.
   __ addl(EAX, Immediate(1 * kWordSize));  // Retval is next to 1st argument.
   __ movl(Address(ESP, retval_offset), EAX);  // Set retval in NativeArguments.
   __ call(ECX);
 
   // Reset exit frame information in Isolate structure.
   __ movl(Address(CTX, Isolate::top_exit_frame_info_offset()), Immediate(0));
 
   // Load Context pointer from Isolate structure into ECX.
@@ skipping 29 matching lines @@
   __ CallRuntime(kPrintStopMessageRuntimeEntry);
   __ LeaveCallRuntimeFrame();
   __ ret();
 }
 
 
 // Input parameters:
 //   ESP : points to return address.
 //   ESP + 4 : address of return value.
 //   EAX : address of first argument in argument array.
-//   EAX - 4*EDX + 4 : address of last argument in argument array.
 //   ECX : address of the native function to call.
-//   EDX : number of arguments to the call.
+//   EDX : argc_tag including number of arguments and function kind.
 // Uses EDI.
 void StubCode::GenerateCallNativeCFunctionStub(Assembler* assembler) {
   const intptr_t native_args_struct_offset = kWordSize;
   const intptr_t isolate_offset =
       NativeArguments::isolate_offset() + native_args_struct_offset;
-  const intptr_t argc_offset =
-      NativeArguments::argc_offset() + native_args_struct_offset;
+  const intptr_t argc_tag_offset =
+      NativeArguments::argc_tag_offset() + native_args_struct_offset;
   const intptr_t argv_offset =
       NativeArguments::argv_offset() + native_args_struct_offset;
   const intptr_t retval_offset =
       NativeArguments::retval_offset() + native_args_struct_offset;
 
   __ EnterFrame(0);
 
   // Load current Isolate pointer from Context structure into EDI.
   __ movl(EDI, FieldAddress(CTX, Context::isolate_offset()));
 
@@ skipping 10 matching lines @@
   // Reserve space for the native arguments structure, the outgoing parameter
   // (pointer to the native arguments structure) and align frame before
   // entering the C++ world.
   __ AddImmediate(ESP, Immediate(-sizeof(NativeArguments) - kWordSize));
   if (OS::ActivationFrameAlignment() > 0) {
     __ andl(ESP, Immediate(~(OS::ActivationFrameAlignment() - 1)));
   }
 
   // Pass NativeArguments structure by value and call native function.
   __ movl(Address(ESP, isolate_offset), CTX);  // Set isolate in NativeArgs.
-  __ movl(Address(ESP, argc_offset), EDX);  // Set argc in NativeArguments.
+  __ movl(Address(ESP, argc_tag_offset), EDX);  // Set argc in NativeArguments.
   __ movl(Address(ESP, argv_offset), EAX);  // Set argv in NativeArguments.
   __ leal(EAX, Address(EBP, 2 * kWordSize));  // Compute return value addr.
   __ movl(Address(ESP, retval_offset), EAX);  // Set retval in NativeArguments.
   __ leal(EAX, Address(ESP, kWordSize));  // Pointer to the NativeArguments.
   __ movl(Address(ESP, 0), EAX);  // Pass the pointer to the NativeArguments.
   __ call(ECX);
 
   // Reset exit frame information in Isolate structure.
   __ movl(Address(CTX, Isolate::top_exit_frame_info_offset()), Immediate(0));
 
@@ skipping 560 matching lines @@
   __ popl(EAX);  // Pop element type argument.
   __ popl(EDX);  // Pop array length argument.
   __ popl(EAX);  // Pop return value from return slot.
   __ LeaveFrame();
   __ ret();
 }
 
 
 // Input parameters:
 //   EDX: Arguments descriptor array (num_args is first Smi element, closure
-//        object is not included in num_args).
-// Note: The closure object is pushed before the first argument to the function
-//       being called, the stub accesses the closure from this location directly
-//       when setting up the context and resolving the entry point.
+//        object is included in num_args and is first argument).
+// Note: The closure object is the first argument to the function being
+//       called, the stub accesses the closure from this location directly
+//       when trying to resolve the call.
 // Uses EDI.
 void StubCode::GenerateCallClosureFunctionStub(Assembler* assembler) {
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
 
   // Total number of args is the first Smi in args descriptor array (EDX).
   __ movl(EAX, FieldAddress(EDX, Array::data_offset()));  // Load num_args.
   // Load closure object in EDI.
-  __ movl(EDI, Address(ESP, EAX, TIMES_2, kWordSize));  // EAX is a Smi.
+  __ movl(EDI, Address(ESP, EAX, TIMES_2, 0));  // EAX is a Smi.
 
   // Verify that EDI is a closure by checking its class.
   Label not_closure;
   __ cmpl(EDI, raw_null);
   // Not a closure, but null object.
   __ j(EQUAL, &not_closure, Assembler::kNearJump);
   __ testl(EDI, Immediate(kSmiTagMask));
   __ 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.
@@ skipping 13 matching lines @@
   __ movl(EAX, FieldAddress(ECX, Function::code_offset()));
   __ cmpl(EAX, raw_null);
   Label function_compiled;
   __ j(NOT_EQUAL, &function_compiled, Assembler::kNearJump);
 
   // Create a stub frame as we are pushing some objects on the stack before
   // calling into the runtime.
   AssemblerMacros::EnterStubFrame(assembler);
 
   __ pushl(EDX);  // Preserve arguments descriptor array.
-  __ pushl(ECX);
+  __ pushl(ECX);  // Preserve read-only function object argument.
   __ CallRuntime(kCompileFunctionRuntimeEntry);
   __ 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.
   // EDX: Arguments descriptor array (num_args is first Smi element).
 
   __ movl(ECX, FieldAddress(EAX, Code::instructions_offset()));
   __ addl(ECX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
   __ jmp(ECX);
 
   __ Bind(&not_closure);
   // Call runtime to report that a closure call was attempted on a non-closure
   // object, passing the non-closure object and its arguments array.
   // EDI: non-closure object.
   // EDX: arguments descriptor array (num_args is first Smi element, closure
-  //      object is not included in num_args).
+  //      object is included in num_args).
 
   // Create a stub frame as we are pushing some objects on the stack before
   // calling into the runtime.
   AssemblerMacros::EnterStubFrame(assembler);
 
   __ pushl(raw_null);  // Setup space on stack for result from error reporting.
   __ pushl(EDI);  // Non-closure object.
     // Total number of args is the first Smi in args descriptor array (EDX).
   __ movl(EDI, FieldAddress(EDX, Array::data_offset()));  // Load num_args.
   __ SmiUntag(EDI);
+  __ subl(EDI, Immediate(1));  // Arguments array length, minus the closure.
   // See stack layout below explaining "wordSize * 5" offset.
   PushArgumentsArray(assembler, (kWordSize * 5));
 
   // Stack:
   // TOS + 0: Argument array.
   // TOS + 1: Non-closure object.
   // TOS + 2: Place for result from reporting the error.
   // TOS + 3: PC marker => RawInstruction object.
   // TOS + 4: Saved EBP of previous frame. <== EBP
   // TOS + 5: Dart code return address
@@ skipping 1236 matching lines @@
   __ Drop(4);
   __ LeaveFrame();
 
   __ jmp(&compute_result, Assembler::kNearJump);
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32