reland 16744: add context save for GenerateFastApiCall

src/arm/macro-assembler-arm.cc

 // Copyright 2012 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 1002 matching lines @@
   // If we are using the simulator then we should always align to the expected
   // alignment. As the simulator is used to generate snapshots we do not know
   // if the target platform will need alignment, so this is controlled from a
   // flag.
   return FLAG_sim_stack_alignment;
 #endif  // V8_HOST_ARCH_ARM
 }
 
 
 void MacroAssembler::LeaveExitFrame(bool save_doubles,
-                                    Register argument_count) {
+                                    Register argument_count,
+                                    bool restore_context) {
   // Optionally restore all double registers.
   if (save_doubles) {
     // Calculate the stack location of the saved doubles and restore them.
     const int offset = 2 * kPointerSize;
     sub(r3, fp,
         Operand(offset + DwVfpRegister::kMaxNumRegisters * kDoubleSize));
     RestoreFPRegs(r3, ip);
   }
 
   // Clear top frame.
   mov(r3, Operand::Zero());
   mov(ip, Operand(ExternalReference(Isolate::kCEntryFPAddress, isolate())));
   str(r3, MemOperand(ip));
 
+
   // Restore current context from top and clear it in debug mode.
+  if (restore_context) {
+    mov(ip, Operand(ExternalReference(Isolate::kContextAddress, isolate())));
+    ldr(cp, MemOperand(ip));
+  }
+#ifdef DEBUG
   mov(ip, Operand(ExternalReference(Isolate::kContextAddress, isolate())));
-  ldr(cp, MemOperand(ip));
-#ifdef DEBUG
   str(r3, MemOperand(ip));
 #endif
 
   // Tear down the exit frame, pop the arguments, and return.
   mov(sp, Operand(fp));
   ldm(ia_w, sp, fp.bit() | lr.bit());
   if (argument_count.is_valid()) {
     add(sp, sp, Operand(argument_count, LSL, kPointerSizeLog2));
   }
 }
@@ skipping 1221 matching lines @@
          stub->CompilingCallsToThisStubIsGCSafe(isolate()));
   Jump(stub->GetCode(isolate()), RelocInfo::CODE_TARGET, cond);
 }
 
 
 static int AddressOffset(ExternalReference ref0, ExternalReference ref1) {
   return ref0.address() - ref1.address();
 }
 
 
-void MacroAssembler::CallApiFunctionAndReturn(ExternalReference function,
-                                              Address function_address,
-                                              ExternalReference thunk_ref,
-                                              Register thunk_last_arg,
-                                              int stack_space,
-                                              int return_value_offset) {
+void MacroAssembler::CallApiFunctionAndReturn(
+    ExternalReference function,
+    Address function_address,
+    ExternalReference thunk_ref,
+    Register thunk_last_arg,
+    int stack_space,
+    MemOperand return_value_operand,
+    MemOperand* context_restore_operand) {
   ExternalReference next_address =
       ExternalReference::handle_scope_next_address(isolate());
   const int kNextOffset = 0;
   const int kLimitOffset = AddressOffset(
       ExternalReference::handle_scope_limit_address(isolate()),
       next_address);
   const int kLevelOffset = AddressOffset(
       ExternalReference::handle_scope_level_address(isolate()),
       next_address);
 
@@ skipping 43 matching lines @@
   if (FLAG_log_timer_events) {
     FrameScope frame(this, StackFrame::MANUAL);
     PushSafepointRegisters();
     PrepareCallCFunction(1, r0);
     mov(r0, Operand(ExternalReference::isolate_address(isolate())));
     CallCFunction(ExternalReference::log_leave_external_function(isolate()), 1);
     PopSafepointRegisters();
   }
 
   Label promote_scheduled_exception;
+  Label exception_handled;
   Label delete_allocated_handles;
   Label leave_exit_frame;
   Label return_value_loaded;
 
   // load value from ReturnValue
-  ldr(r0, MemOperand(fp, return_value_offset*kPointerSize));
+  ldr(r0, return_value_operand);
   bind(&return_value_loaded);
   // No more valid handles (the result handle was the last one). Restore
   // previous handle scope.
   str(r4, MemOperand(r7, kNextOffset));
   if (emit_debug_code()) {
     ldr(r1, MemOperand(r7, kLevelOffset));
     cmp(r1, r6);
     Check(eq, kUnexpectedLevelAfterReturnFromApiCall);
   }
   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(isolate())));
   ldr(r5, MemOperand(ip));
   cmp(r4, r5);
   b(ne, &promote_scheduled_exception);
+  bind(&exception_handled);
 
+  bool restore_context = context_restore_operand != NULL;
+  if (restore_context) {
+    ldr(cp, *context_restore_operand);
+  }
   // LeaveExitFrame expects unwind space to be in a register.
   mov(r4, Operand(stack_space));
-  LeaveExitFrame(false, r4);
+  LeaveExitFrame(false, r4, !restore_context);
   mov(pc, lr);
 
   bind(&promote_scheduled_exception);
-  TailCallExternalReference(
-      ExternalReference(Runtime::kPromoteScheduledException, isolate()),
-      0,
-      1);
+  {
+    FrameScope frame(this, StackFrame::INTERNAL);
+    CallExternalReference(
+        ExternalReference(Runtime::kPromoteScheduledException, isolate()),
+        0);
+  }
+  jmp(&exception_handled);
 
   // HandleScope limit has changed. Delete allocated extensions.
   bind(&delete_allocated_handles);
   str(r5, MemOperand(r7, kLimitOffset));
   mov(r4, r0);
   PrepareCallCFunction(1, r5);
   mov(r0, Operand(ExternalReference::isolate_address(isolate())));
   CallCFunction(
       ExternalReference::delete_handle_scope_extensions(isolate()), 1);
   mov(r0, r4);
@@ skipping 1483 matching lines @@
 void CodePatcher::EmitCondition(Condition cond) {
   Instr instr = Assembler::instr_at(masm_.pc_);
   instr = (instr & ~kCondMask) | cond;
   masm_.emit(instr);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM