Direct call api functions (arm implementation)

src/arm/macro-assembler-arm.cc

 // Copyright 2011 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 614 matching lines @@
   // r1: preserved
   // r2: preserved
 
   // Drop the execution stack down to the frame pointer and restore
   // the caller frame pointer and return address.
   mov(sp, fp);
   ldm(ia_w, sp, fp.bit() | lr.bit());
 }
 
 
-void MacroAssembler::EnterExitFrame(bool save_doubles) {
-  // Compute the argv pointer in a callee-saved register.
-  add(r6, sp, Operand(r0, LSL, kPointerSizeLog2));
-  sub(r6, r6, Operand(kPointerSize));
-
+void MacroAssembler::EnterExitFrame(bool save_doubles, int stack_space) {
   // Setup the frame structure on the stack.
   ASSERT_EQ(2 * kPointerSize, ExitFrameConstants::kCallerSPDisplacement);
   ASSERT_EQ(1 * kPointerSize, ExitFrameConstants::kCallerPCOffset);
   ASSERT_EQ(0 * kPointerSize, ExitFrameConstants::kCallerFPOffset);
   Push(lr, fp);
   mov(fp, Operand(sp));  // Setup new frame pointer.
   // Reserve room for saved entry sp and code object.
   sub(sp, sp, Operand(2 * kPointerSize));
   if (FLAG_debug_code) {
     mov(ip, Operand(0));
     str(ip, MemOperand(fp, ExitFrameConstants::kSPOffset));
   }
   mov(ip, Operand(CodeObject()));
   str(ip, MemOperand(fp, ExitFrameConstants::kCodeOffset));
 
   // Save the frame pointer and the context in top.
   mov(ip, Operand(ExternalReference(Top::k_c_entry_fp_address)));
   str(fp, MemOperand(ip));
   mov(ip, Operand(ExternalReference(Top::k_context_address)));
   str(cp, MemOperand(ip));
 
-  // Setup argc and the builtin function in callee-saved registers.
-  mov(r4, Operand(r0));
-  mov(r5, Operand(r1));
-
   // Optionally save all double registers.
   if (save_doubles) {
     sub(sp, sp, Operand(DwVfpRegister::kNumRegisters * kDoubleSize));
     const int offset = -2 * kPointerSize;
     for (int i = 0; i < DwVfpRegister::kNumRegisters; i++) {
       DwVfpRegister reg = DwVfpRegister::from_code(i);
       vstr(reg, fp, offset - ((i + 1) * kDoubleSize));
     }
     // Note that d0 will be accessible at
     //   fp - 2 * kPointerSize - DwVfpRegister::kNumRegisters * kDoubleSize,
     // since the sp slot and code slot were pushed after the fp.
   }
 
-  // Reserve place for the return address and align the frame preparing for
-  // calling the runtime function.
+  // Reserve place for the return address and stack space and align the frame
+  // preparing for calling the runtime function.
   const int frame_alignment = MacroAssembler::ActivationFrameAlignment();
-  sub(sp, sp, Operand(kPointerSize));
+  sub(sp, sp, Operand((stack_space + 1) * kPointerSize));
   if (frame_alignment > 0) {
     ASSERT(IsPowerOf2(frame_alignment));
     and_(sp, sp, Operand(-frame_alignment));
   }
 
   // Set the exit frame sp value to point just before the return address
   // location.
   add(ip, sp, Operand(kPointerSize));
   str(ip, MemOperand(fp, ExitFrameConstants::kSPOffset));
 }
@@ skipping 776 matching lines @@
   // in initial map.
   bind(&non_instance);
   ldr(result, FieldMemOperand(result, Map::kConstructorOffset));
 
   // All done.
   bind(&done);
 }
 
 
 void MacroAssembler::CallStub(CodeStub* stub, Condition cond) {
-  ASSERT(allow_stub_calls());  // stub calls are not allowed in some stubs
+  ASSERT(allow_stub_calls());  // Stub calls are not allowed in some stubs.
   Call(stub->GetCode(), RelocInfo::CODE_TARGET, cond);
 }
 
 
 void MacroAssembler::TailCallStub(CodeStub* stub, Condition cond) {
-  ASSERT(allow_stub_calls());  // stub calls are not allowed in some stubs
+  ASSERT(allow_stub_calls());  // Stub calls are not allowed in some stubs.
   Jump(stub->GetCode(), RelocInfo::CODE_TARGET, cond);
 }
 
 
+MaybeObject* MacroAssembler::TryTailCallStub(CodeStub* stub, Condition cond) {
+  ASSERT(allow_stub_calls());  // Stub calls are not allowed in some stubs.
+  Object* result;
+  { MaybeObject* maybe_result = stub->TryGetCode();
+    if (!maybe_result->ToObject(&result)) return maybe_result;
+  }
+  Jump(stub->GetCode(), RelocInfo::CODE_TARGET, cond);
+  return result;
+}
+
+
+static int AddressOffset(ExternalReference ref0, ExternalReference ref1) {
+  return ref0.address() - ref1.address();
+}
+
+
+MaybeObject* MacroAssembler::TryCallApiFunctionAndReturn(
+    ApiFunction* function, int stack_space) {
+  ExternalReference next_address =
+      ExternalReference::handle_scope_next_address();
+  const int kNextOffset = 0;
+  const int kLimitOffset = AddressOffset(
+      ExternalReference::handle_scope_limit_address(),
+      next_address);
+  const int kLevelOffset = AddressOffset(
+      ExternalReference::handle_scope_level_address(),
+      next_address);
+
+  // Allocate HandleScope in callee-save registers.
+  mov(r7, Operand(next_address));
+  ldr(r4, MemOperand(r7, kNextOffset));
+  ldr(r5, MemOperand(r7, kLimitOffset));
+  ldr(r6, MemOperand(r7, kLevelOffset));
+  add(r6, r6, Operand(1));
+  str(r6, MemOperand(r7, kLevelOffset));
+
+  // Native call returns to the DirectCEntry stub which redirects to the
+  // return address pushed on stack (could have moved after GC).
+  // DirectCEntry stub itself is generated early and never moves.
+  DirectCEntryStub stub;
+  stub.GenerateCall(this, function);
+
+  Label promote_scheduled_exception;
+  Label delete_allocated_handles;
+  Label leave_exit_frame;
+
+  // If result is non-zero, dereference to get the result value
+  // otherwise set it to undefined.
+  cmp(r0, Operand(0));
+  LoadRoot(r0, Heap::kUndefinedValueRootIndex, eq);
+  ldr(r0, MemOperand(r0), ne);
+
+  // No more valid handles (the result handle was the last one). Restore
+  // previous handle scope.
+  str(r4, MemOperand(r7, kNextOffset));
+  if (FLAG_debug_code) {
+    ldr(r1, MemOperand(r7, kLevelOffset));
+    cmp(r1, r6);
+    Check(eq, "Unexpected level after return from api call");
+  }
+  sub(r6, r6, Operand(1));
+  str(r6, MemOperand(r7, kLevelOffset));
+  ldr(ip, MemOperand(r7, kLimitOffset));
+  cmp(r5, ip);
+  b(ne, &delete_allocated_handles);
+
+  // Check if the function scheduled an exception.
+  bind(&leave_exit_frame);
+  LoadRoot(r4, Heap::kTheHoleValueRootIndex);
+  mov(ip, Operand(ExternalReference::scheduled_exception_address()));
+  ldr(r5, MemOperand(ip));
+  cmp(r4, r5);
+  b(ne, &promote_scheduled_exception);
+
+  // LeaveExitFrame expects unwind space to be in r4.
+  mov(r4, Operand(stack_space));
+  LeaveExitFrame(false);
+
+  bind(&promote_scheduled_exception);
+  MaybeObject* result = TryTailCallExternalReference(
+      ExternalReference(Runtime::kPromoteScheduledException), 0, 1);
+  if (result->IsFailure()) {
+    return result;
+  }
+
+  // HandleScope limit has changed. Delete allocated extensions.
+  bind(&delete_allocated_handles);
+  str(r5, MemOperand(r7, kLimitOffset));
+  mov(r4, r0);
+  PrepareCallCFunction(0, r5);
+  CallCFunction(ExternalReference::delete_handle_scope_extensions(), 0);
+  mov(r0, r4);
+  jmp(&leave_exit_frame);
+
+  return result;
+}
+
+
 void MacroAssembler::IllegalOperation(int num_arguments) {
   if (num_arguments > 0) {
     add(sp, sp, Operand(num_arguments * kPointerSize));
   }
   LoadRoot(r0, Heap::kUndefinedValueRootIndex);
 }
 
 
 void MacroAssembler::IndexFromHash(Register hash, Register index) {
   // If the hash field contains an array index pick it out. The assert checks
@@ skipping 232 matching lines @@
                                                int num_arguments,
                                                int result_size) {
   // TODO(1236192): Most runtime routines don't need the number of
   // arguments passed in because it is constant. At some point we
   // should remove this need and make the runtime routine entry code
   // smarter.
   mov(r0, Operand(num_arguments));
   JumpToExternalReference(ext);
 }
 
+MaybeObject* MacroAssembler::TryTailCallExternalReference(
+    const ExternalReference& ext, int num_arguments, int result_size) {
+  // TODO(1236192): Most runtime routines don't need the number of
+  // arguments passed in because it is constant. At some point we
+  // should remove this need and make the runtime routine entry code
+  // smarter.
+  mov(r0, Operand(num_arguments));
+  return TryJumpToExternalReference(ext);
+}
 
 void MacroAssembler::TailCallRuntime(Runtime::FunctionId fid,
                                      int num_arguments,
                                      int result_size) {
   TailCallExternalReference(ExternalReference(fid), num_arguments, result_size);
 }
 
 
 void MacroAssembler::JumpToExternalReference(const ExternalReference& builtin) {
 #if defined(__thumb__)
   // Thumb mode builtin.
   ASSERT((reinterpret_cast<intptr_t>(builtin.address()) & 1) == 1);
 #endif
   mov(r1, Operand(builtin));
   CEntryStub stub(1);
   Jump(stub.GetCode(), RelocInfo::CODE_TARGET);
 }
 
+MaybeObject* MacroAssembler::TryJumpToExternalReference(
+    const ExternalReference& builtin) {
+#if defined(__thumb__)
+  // Thumb mode builtin.
+  ASSERT((reinterpret_cast<intptr_t>(builtin.address()) & 1) == 1);
+#endif
+  mov(r1, Operand(builtin));
+  CEntryStub stub(1);
+  return TryTailCallStub(&stub);
+}
 
 void MacroAssembler::InvokeBuiltin(Builtins::JavaScript id,
                                    InvokeJSFlags flags,
                                    PostCallGenerator* post_call_generator) {
   GetBuiltinEntry(r2, id);
   if (flags == CALL_JS) {
     Call(r2);
     if (post_call_generator != NULL) post_call_generator->Generate();
   } else {
     ASSERT(flags == JUMP_JS);
@@ skipping 505 matching lines @@
 
 void CodePatcher::Emit(Address addr) {
   masm()->emit(reinterpret_cast<Instr>(addr));
 }
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM