[generators] Store the resume mode in the generator object.

src/arm64/builtins-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/arm64/frames-arm64.h"
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
@@ skipping 708 matching lines @@
   //  -- x2 : the resume mode (tagged)
   //  -- lr : return address
   // -----------------------------------
   __ AssertGeneratorObject(x1);
 
   // Store input value into generator object.
   __ Str(x0, FieldMemOperand(x1, JSGeneratorObject::kInputOffset));
   __ RecordWriteField(x1, JSGeneratorObject::kInputOffset, x0, x3,
                       kLRHasNotBeenSaved, kDontSaveFPRegs);
 
+  // Store resume mode into generator object.
+  __ Str(x2, FieldMemOperand(x1, JSGeneratorObject::kResumeModeOffset));
+
   // Load suspended function and context.
   __ Ldr(cp, FieldMemOperand(x1, JSGeneratorObject::kContextOffset));
   __ Ldr(x4, FieldMemOperand(x1, JSGeneratorObject::kFunctionOffset));
 
   // Flood function if we are stepping.
   Label skip_flooding;
   ExternalReference step_in_enabled =
       ExternalReference::debug_step_in_enabled_address(masm->isolate());
   __ Mov(x10, Operand(step_in_enabled));
   __ Ldrb(x10, MemOperand(x10));
@@ skipping 51 matching lines @@
     Label done_loop, loop;
     __ Bind(&loop);
     __ Cmp(x0, x3);
     __ B(eq, &done_loop);
     __ Ldr(x10, MemOperand(x0, kPointerSize, PostIndex));
     __ Push(x10);
     __ B(&loop);
     __ Bind(&done_loop);
   }
 
-  // Push resume mode (consumed in continuation).
-  __ Push(x2);
-
   // Reset operand stack so we don't leak.
   __ LoadRoot(x10, Heap::kEmptyFixedArrayRootIndex);
   __ Str(x10, FieldMemOperand(x1, JSGeneratorObject::kOperandStackOffset));
 
-  // Restore value.
-  __ Ldr(x0, FieldMemOperand(x1, JSGeneratorObject::kInputOffset));
-
   // Resume the generator function at the continuation.
   __ Ldr(x10, FieldMemOperand(x4, JSFunction::kSharedFunctionInfoOffset));
   __ Ldr(x10, FieldMemOperand(x10, SharedFunctionInfo::kCodeOffset));
   __ Add(x10, x10, Code::kHeaderSize - kHeapObjectTag);
   __ Ldrsw(x11,
            UntagSmiFieldMemOperand(x1, JSGeneratorObject::kContinuationOffset));
   __ Add(x10, x10, x11);
   __ Mov(x12, Smi::FromInt(JSGeneratorObject::kGeneratorExecuting));
   __ Str(x12, FieldMemOperand(x1, JSGeneratorObject::kContinuationOffset));
+  __ Move(x0, x1);  // Continuation expects generator object in x0.
   __ Br(x10);
 }
 
 enum IsTagged { kArgcIsSmiTagged, kArgcIsUntaggedInt };
 
 
 // Clobbers x10, x15; preserves all other registers.
 static void Generate_CheckStackOverflow(MacroAssembler* masm, Register argc,
                                         IsTagged argc_is_tagged) {
   // Check the stack for overflow.
@@ skipping 1931 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM