[fullcodegen] Remove deprecated generator implementation.

src/builtins/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 771 matching lines @@
   // Push holes for arguments to generator function. Since the parser forced
   // context allocation for any variables in generators, the actual argument
   // values have already been copied into the context and these dummy values
   // will never be used.
   __ Ldr(x10, FieldMemOperand(x4, JSFunction::kSharedFunctionInfoOffset));
   __ Ldr(w10,
          FieldMemOperand(x10, SharedFunctionInfo::kFormalParameterCountOffset));
   __ LoadRoot(x11, Heap::kTheHoleValueRootIndex);
   __ PushMultipleTimes(x11, w10);
 
-  // Dispatch on the kind of generator object.
-  Label old_generator;
-  __ Ldr(x3, FieldMemOperand(x4, JSFunction::kSharedFunctionInfoOffset));
-  __ Ldr(x3, FieldMemOperand(x3, SharedFunctionInfo::kFunctionDataOffset));
-  __ CompareObjectType(x3, x3, x3, BYTECODE_ARRAY_TYPE);
-  __ B(ne, &old_generator);
+  // Underlying function needs to have bytecode available.
+  if (FLAG_debug_code) {
+    __ Ldr(x3, FieldMemOperand(x4, JSFunction::kSharedFunctionInfoOffset));
+    __ Ldr(x3, FieldMemOperand(x3, SharedFunctionInfo::kFunctionDataOffset));
+    __ CompareObjectType(x3, x3, x3, BYTECODE_ARRAY_TYPE);
+    __ Assert(eq, kMissingBytecodeArray);
+  }
 
-  // New-style (ignition/turbofan) generator object
+  // Resume (Ignition/TurboFan) generator object.
   {
     __ Ldr(x0, FieldMemOperand(x4, JSFunction::kSharedFunctionInfoOffset));
     __ Ldr(w0, FieldMemOperand(
                    x0, SharedFunctionInfo::kFormalParameterCountOffset));
     // We abuse new.target both to indicate that this is a resume call and to
     // pass in the generator object.  In ordinary calls, new.target is always
     // undefined because generator functions are non-constructable.
     __ Move(x3, x1);
     __ Move(x1, x4);
     __ Ldr(x5, FieldMemOperand(x1, JSFunction::kCodeEntryOffset));
     __ Jump(x5);
   }
 
-  // Old-style (full-codegen) generator object
-  __ bind(&old_generator);
-  {
-    // Enter a new JavaScript frame, and initialize its slots as they were when
-    // the generator was suspended.
-    FrameScope scope(masm, StackFrame::MANUAL);
-    __ Push(lr, fp);
-    __ Move(fp, jssp);
-    __ Push(cp, x4);
-
-    // Restore the operand stack.
-    __ Ldr(x0, FieldMemOperand(x1, JSGeneratorObject::kOperandStackOffset));
-    __ Ldr(w3, UntagSmiFieldMemOperand(x0, FixedArray::kLengthOffset));
-    __ Add(x0, x0, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-    __ Add(x3, x0, Operand(x3, LSL, kPointerSizeLog2));
-    {
-      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);
-    }
-
-    // Reset operand stack so we don't leak.
-    __ LoadRoot(x10, Heap::kEmptyFixedArrayRootIndex);
-    __ Str(x10, FieldMemOperand(x1, JSGeneratorObject::kOperandStackOffset));
-
-    // 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);
-  }
-
   __ Bind(&prepare_step_in_if_stepping);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
     __ Push(x1, x2, x4);
     __ CallRuntime(Runtime::kDebugPrepareStepInIfStepping);
     __ Pop(x2, x1);
     __ Ldr(x4, FieldMemOperand(x1, JSGeneratorObject::kFunctionOffset));
   }
   __ B(&stepping_prepared);
 
@@ skipping 2143 matching lines @@
     __ Unreachable();
   }
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM