First version of the new generators implementation.

src/arm/builtins-arm.cc

Index: src/arm/builtins-arm.cc
diff --git a/src/arm/builtins-arm.cc b/src/arm/builtins-arm.cc
index 1799090aa108559ec43a6a44350387aa61b79acc..c6e9f445049ba7384b2db8deca0d14b0e3e35f1e 100644
--- a/src/arm/builtins-arm.cc
+++ b/src/arm/builtins-arm.cc
@@ -773,44 +773,70 @@ void Builtins::Generate_ResumeGeneratorTrampoline(MacroAssembler* masm) {
     __ bind(&done_loop);
   }
 
-  // Enter a new JavaScript frame, and initialize its slots as they were when
-  // the generator was suspended.
-  DCHECK(!FLAG_enable_embedded_constant_pool);
-  FrameScope scope(masm, StackFrame::MANUAL);
-  __ Push(lr, fp);
-  __ Move(fp, sp);
-  __ Push(cp, r4);
-
-  // Restore the operand stack.
-  __ ldr(r0, FieldMemOperand(r1, JSGeneratorObject::kOperandStackOffset));
-  __ ldr(r3, FieldMemOperand(r0, FixedArray::kLengthOffset));
-  __ add(r0, r0, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
-  __ add(r3, r0, Operand(r3, LSL, kPointerSizeLog2 - 1));
+  // Dispatch on the kind of generator object.
+  Label old_generator;
+  __ ldr(r3, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
+  __ ldr(r3, FieldMemOperand(r3, SharedFunctionInfo::kFunctionDataOffset));
+  __ CompareObjectType(r3, r3, r3, BYTECODE_ARRAY_TYPE);
+  __ b(ne, &old_generator);
+
+  // New-style (ignition/turbofan) generator object
   {
-    Label done_loop, loop;
-    __ bind(&loop);
-    __ cmp(r0, r3);
-    __ b(eq, &done_loop);
-    __ ldr(ip, MemOperand(r0, kPointerSize, PostIndex));
-    __ Push(ip);
-    __ b(&loop);
-    __ bind(&done_loop);
+    __ ldr(r0, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
+    __ ldr(r0,
+         FieldMemOperand(r0, SharedFunctionInfo::kFormalParameterCountOffset));
+    __ SmiUntag(r0);
+    // 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(r3, r1);
+    __ Move(r1, r4);
+    __ ldr(r5, FieldMemOperand(r1, JSFunction::kCodeEntryOffset));
+    __ Jump(r5);
   }
 
-  // Reset operand stack so we don't leak.
-  __ LoadRoot(ip, Heap::kEmptyFixedArrayRootIndex);
-  __ str(ip, FieldMemOperand(r1, JSGeneratorObject::kOperandStackOffset));
+  // 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.
+    DCHECK(!FLAG_enable_embedded_constant_pool);
+    FrameScope scope(masm, StackFrame::MANUAL);
+    __ Push(lr, fp);
+    __ Move(fp, sp);
+    __ Push(cp, r4);
+
+    // Restore the operand stack.
+    __ ldr(r0, FieldMemOperand(r1, JSGeneratorObject::kOperandStackOffset));
+    __ ldr(r3, FieldMemOperand(r0, FixedArray::kLengthOffset));
+    __ add(r0, r0, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
+    __ add(r3, r0, Operand(r3, LSL, kPointerSizeLog2 - 1));
+    {
+      Label done_loop, loop;
+      __ bind(&loop);
+      __ cmp(r0, r3);
+      __ b(eq, &done_loop);
+      __ ldr(ip, MemOperand(r0, kPointerSize, PostIndex));
+      __ Push(ip);
+      __ b(&loop);
+      __ bind(&done_loop);
+    }
 
-  // Resume the generator function at the continuation.
-  __ ldr(r3, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
-  __ ldr(r3, FieldMemOperand(r3, SharedFunctionInfo::kCodeOffset));
-  __ add(r3, r3, Operand(Code::kHeaderSize - kHeapObjectTag));
-  __ ldr(r2, FieldMemOperand(r1, JSGeneratorObject::kContinuationOffset));
-  __ add(r3, r3, Operand(r2, ASR, 1));
-  __ mov(r2, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorExecuting)));
-  __ str(r2, FieldMemOperand(r1, JSGeneratorObject::kContinuationOffset));
-  __ Move(r0, r1);  // Continuation expects generator object in r0.
-  __ Jump(r3);
+    // Reset operand stack so we don't leak.
+    __ LoadRoot(ip, Heap::kEmptyFixedArrayRootIndex);
+    __ str(ip, FieldMemOperand(r1, JSGeneratorObject::kOperandStackOffset));
+
+    // Resume the generator function at the continuation.
+    __ ldr(r3, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
+    __ ldr(r3, FieldMemOperand(r3, SharedFunctionInfo::kCodeOffset));
+    __ add(r3, r3, Operand(Code::kHeaderSize - kHeapObjectTag));
+    __ ldr(r2, FieldMemOperand(r1, JSGeneratorObject::kContinuationOffset));
+    __ add(r3, r3, Operand(r2, ASR, 1));
+    __ mov(r2, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorExecuting)));
+    __ str(r2, FieldMemOperand(r1, JSGeneratorObject::kContinuationOffset));
+    __ Move(r0, r1);  // Continuation expects generator object in r0.
+    __ Jump(r3);
+  }
 }
 
 void Builtins::Generate_ConstructedNonConstructable(MacroAssembler* masm) {