Direct call api functions (arm implementation)

src/arm/stub-cache-arm.cc

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 553 matching lines @@
 
   ExternalReference ref =
       ExternalReference(IC_Utility(IC::kLoadPropertyWithInterceptorOnly));
   __ mov(r0, Operand(5));
   __ mov(r1, Operand(ref));
 
   CEntryStub stub(1);
   __ CallStub(&stub);
 }
 
+#ifdef USE_SIMULATOR
+static const int kFastApiCallArguments = 4;
+#else
+static const int kFastApiCallArguments = 3;
+#endif
 
 // Reserves space for the extra arguments to FastHandleApiCall in the
 // caller's frame.
 //
 // These arguments are set by CheckPrototypes and GenerateFastApiCall.
 static void ReserveSpaceForFastApiCall(MacroAssembler* masm,
                                        Register scratch) {
   __ mov(scratch, Operand(Smi::FromInt(0)));
-  __ push(scratch);
-  __ push(scratch);
-  __ push(scratch);
-  __ push(scratch);
+  for (int i = 0; i < kFastApiCallArguments; i++) {
+    __ push(scratch);
+  }
 }
 
 
 // Undoes the effects of ReserveSpaceForFastApiCall.
 static void FreeSpaceForFastApiCall(MacroAssembler* masm) {
-  __ Drop(4);
+  __ Drop(kFastApiCallArguments);
 }
 
 
 // Generates call to FastHandleApiCall builtin.
 static void GenerateFastApiCall(MacroAssembler* masm,
                                 const CallOptimization& optimization,
                                 int argc) {
   // Get the function and setup the context.
   JSFunction* function = optimization.constant_function();
   __ mov(r5, Operand(Handle<JSFunction>(function)));
@@ skipping 27 matching lines @@
   __ mov(r0, Operand(argc + 4));
 
   // Jump to the fast api call builtin (tail call).
   Handle<Code> code = Handle<Code>(
       Builtins::builtin(Builtins::FastHandleApiCall));
   ParameterCount expected(0);
   __ InvokeCode(code, expected, expected,
                 RelocInfo::CODE_TARGET, JUMP_FUNCTION);
 }
 
+#ifndef USE_SIMULATOR
+static bool GenerateFastApiDirectCall(MacroAssembler* masm,
+                                const CallOptimization& optimization,

[antonm, 2011/01/11 14:11:33]

nit: indentation is slightly off

[Zaheer, 2011/01/11 15:44:35]

Done

+                                int argc,
+                                Failure** failure) {

[antonm, 2011/01/11 14:11:33]

may you add a stack map like in ia32 version?

[Zaheer, 2011/01/11 15:44:35]

Done

+  // Get the function and setup the context.
+  JSFunction* function = optimization.constant_function();
+  __ mov(r5, Operand(Handle<JSFunction>(function)));
+  __ ldr(cp, FieldMemOperand(r5, JSFunction::kContextOffset));
+
+  // Pass the additional arguments FastHandleApiCall expects.
+  Object* call_data = optimization.api_call_info()->data();
+  Handle<CallHandlerInfo> api_call_info_handle(optimization.api_call_info());
+  if (Heap::InNewSpace(call_data)) {
+    __ Move(r0, api_call_info_handle);
+    __ ldr(r6, FieldMemOperand(r0, CallHandlerInfo::kDataOffset));
+  } else {
+    __ Move(r6, Handle<Object>(call_data));
+  }
+  __ stm(ib, sp, r5.bit() | r6.bit());

[antonm, 2011/01/11 14:11:33]

please, add a comment what are you doing here.

+  __ add(r2, sp, Operand(2 * kPointerSize));  // r2 = data
+
+  Object* callback = optimization.api_call_info()->callback();
+  Address api_function_address = v8::ToCData<Address>(callback);
+  ApiFunction fun(api_function_address);
+
+  const int kApiStackSpace = 4;
+  __ PrepareCallApiFunction(kApiStackSpace,
+                            argc + kFastApiCallArguments + 1,
+                            r4);
+  // v8::Arguments::implicit_args = data
+  __ str(r2, MemOperand(sp));

[antonm, 2011/01/11 14:11:33]

I don't know if it'd be faster, but maybe you can use memoperand that post
increment pointer to arrange this sequence of stores, something like:

__ mov(r4, sp);
__ str(r2, MemOperand(r4, kPointerSize, PostIndex);
__ add(ip, r2, ...);
__ str(ip, MemOperand(r4, kPointerSize, PostIndex);
// etc.

[Zaheer, 2011/01/11 15:44:35]

will check

+  __ add(ip, r2, Operand(argc * kPointerSize));
+  // v8::Arguments::values = last argument
+  __ str(ip, MemOperand(sp, 1 * kPointerSize));
+  __ mov(ip, Operand(argc));
+  // v8::Arguments::length_ = argc

[antonm, 2011/01/11 14:11:33]

for me comments are one line below they should be: I'd prefer to have //
v8::Arguments::length_ = argc followed by mov(ip, Operand(argc)) and str(ip,
...)

[Zaheer, 2011/01/11 15:44:35]

Mistake! fixed

+  __ str(ip, MemOperand(sp, 2 * kPointerSize));
+  __ mov(ip, Operand(0));
+  // v8::Arguments::is_construct_call = 0
+  __ str(ip, MemOperand(sp, 3 * kPointerSize));
+  // r0 = v8::Arguments&
+  __ mov(r0, sp);
+
+  // Emitting a stub call may try to allocate (if the code is not
+  // already generated).  Do not allow the assembler to perform a
+  // garbage collection but instead return the allocation failure
+  // object.
+  MaybeObject* result =
+      masm->TryCallApiFunctionAndReturn(&fun);
+  if (result->IsFailure()) {
+    *failure = Failure::cast(result);
+    return false;
+  }
+  return true;
+}
+#endif
+
 
 class CallInterceptorCompiler BASE_EMBEDDED {
  public:
   CallInterceptorCompiler(StubCompiler* stub_compiler,
                           const ParameterCount& arguments,
                           Register name)
       : stub_compiler_(stub_compiler),
         arguments_(arguments),
         name_(name) {}
 
-  void Compile(MacroAssembler* masm,
+  bool Compile(MacroAssembler* masm,
                JSObject* object,
                JSObject* holder,
                String* name,
                LookupResult* lookup,
                Register receiver,
                Register scratch1,
                Register scratch2,
                Register scratch3,
-               Label* miss) {
+               Label* miss,
+               Failure **failure) {
     ASSERT(holder->HasNamedInterceptor());
     ASSERT(!holder->GetNamedInterceptor()->getter()->IsUndefined());
 
     // Check that the receiver isn't a smi.
     __ BranchOnSmi(receiver, miss);
 
     CallOptimization optimization(lookup);
 
     if (optimization.is_constant_call()) {
-      CompileCacheable(masm,
+      return CompileCacheable(masm,
                        object,
                        receiver,
                        scratch1,
                        scratch2,
                        scratch3,
                        holder,
                        lookup,
                        name,
                        optimization,
-                       miss);
+                       miss,
+                       failure);
     } else {
       CompileRegular(masm,
                      object,
                      receiver,
                      scratch1,
                      scratch2,
                      scratch3,
                      name,
                      holder,
                      miss);
+      return true;
     }
   }
 
  private:
-  void CompileCacheable(MacroAssembler* masm,
+  bool CompileCacheable(MacroAssembler* masm,
                        JSObject* object,
                        Register receiver,
                        Register scratch1,
                        Register scratch2,
                        Register scratch3,
                        JSObject* interceptor_holder,
                        LookupResult* lookup,
                        String* name,
                        const CallOptimization& optimization,
-                       Label* miss_label) {
+                       Label* miss_label,
+                       Failure **failure) {
     ASSERT(optimization.is_constant_call());
     ASSERT(!lookup->holder()->IsGlobalObject());
 
     int depth1 = kInvalidProtoDepth;
     int depth2 = kInvalidProtoDepth;
     bool can_do_fast_api_call = false;
     if (optimization.is_simple_api_call() &&
        !lookup->holder()->IsGlobalObject()) {
      depth1 =
          optimization.GetPrototypeDepthOfExpectedType(object,
@@ skipping 43 matching lines @@
     } else {
       // CheckPrototypes has a side effect of fetching a 'holder'
       // for API (object which is instanceof for the signature).  It's
       // safe to omit it here, as if present, it should be fetched
       // by the previous CheckPrototypes.
       ASSERT(depth2 == kInvalidProtoDepth);
     }
 
     // Invoke function.
     if (can_do_fast_api_call) {
+#ifdef USE_SIMULATOR
       GenerateFastApiCall(masm, optimization, arguments_.immediate());
+#else
+      bool success = GenerateFastApiDirectCall(masm,
+                                               optimization,
+                                               arguments_.immediate(),
+                                               failure);
+      if (!success) {
+        return false;
+      }
+#endif
     } else {
       __ InvokeFunction(optimization.constant_function(), arguments_,
                         JUMP_FUNCTION);
     }
 
     // Deferred code for fast API call case---clean preallocated space.
     if (can_do_fast_api_call) {
       __ bind(&miss_cleanup);
       FreeSpaceForFastApiCall(masm);
       __ b(miss_label);
     }
 
     // Invoke a regular function.
     __ bind(&regular_invoke);
     if (can_do_fast_api_call) {
       FreeSpaceForFastApiCall(masm);
     }
+
+    return true;
   }
 
   void CompileRegular(MacroAssembler* masm,
                       JSObject* object,
                       Register receiver,
                       Register scratch1,
                       Register scratch2,
                       Register scratch3,
                       String* name,
                       JSObject* interceptor_holder,
@@ skipping 1436 matching lines @@
                         r1, r4, name, &miss);
       }
       break;
     }
 
     default:
       UNREACHABLE();
   }
 
   if (depth != kInvalidProtoDepth) {
+#ifdef USE_SIMULATOR

[antonm, 2011/01/11 14:11:33]

do we need a special case for simulator?

[Zaheer, 2011/01/11 15:44:35]

currently the simulator interface to the native api expects a argc, argv and
direct call breaks that (it has a v8::Arguments&). I wasnt sure how to fix this
in the simulator, but it would be great if we can do it. 

[antonm, 2011/01/11 19:27:40]

I see, let's ask Erik, maybe he can suggest something.  I am concerned with the
testability of this change---I think most of the people use simulator to run
tests so we can miss errors.

     GenerateFastApiCall(masm(), optimization, argc);
+#else
+    Failure* failure;
+    bool success = GenerateFastApiDirectCall(masm(),
+                                             optimization,
+                                             argc,
+                                             &failure);
+    if (!success) {
+      return failure;
+    }
+#endif
   } else {
     __ InvokeFunction(function, arguments(), JUMP_FUNCTION);
   }
 
   // Handle call cache miss.
   __ bind(&miss);
   if (depth != kInvalidProtoDepth) {
     FreeSpaceForFastApiCall(masm());
   }
 
@@ skipping 23 matching lines @@
   // Get the number of arguments.
   const int argc = arguments().immediate();
 
   LookupResult lookup;
   LookupPostInterceptor(holder, name, &lookup);
 
   // Get the receiver from the stack.
   __ ldr(r1, MemOperand(sp, argc * kPointerSize));
 
   CallInterceptorCompiler compiler(this, arguments(), r2);
-  compiler.Compile(masm(),
+  Failure *failure;
+  bool success =  compiler.Compile(masm(),
                    object,
                    holder,
                    name,
                    &lookup,
                    r1,
                    r3,
                    r4,
                    r0,
-                   &miss);
+                   &miss,
+                   &failure);
+  if (!success) {
+      return false;
+  }
 
   // Move returned value, the function to call, to r1.
   __ mov(r1, r0);
   // Restore receiver.
   __ ldr(r0, MemOperand(sp, argc * kPointerSize));
 
   GenerateCallFunction(masm(), object, arguments(), &miss);
 
   // Handle call cache miss.
   __ bind(&miss);
@@ skipping 895 matching lines @@
   // Return the generated code.
   return GetCode();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM