Version 3.6.5

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 24 matching lines @@
 #include "codegen.h"
 #include "debug.h"
 #include "runtime.h"
 
 namespace v8 {
 namespace internal {
 
 MacroAssembler::MacroAssembler(Isolate* arg_isolate, void* buffer, int size)
     : Assembler(arg_isolate, buffer, size),
       generating_stub_(false),
-      allow_stub_calls_(true) {
+      allow_stub_calls_(true),
+      has_frame_(false) {
   if (isolate() != NULL) {
     code_object_ = Handle<Object>(isolate()->heap()->undefined_value(),
                                   isolate());
   }
 }
 
 
 // We always generate arm code, never thumb code, even if V8 is compiled to
 // thumb, so we require inter-working support
 #if defined(__thumb__) && !defined(USE_THUMB_INTERWORK)
@@ skipping 343 matching lines @@
 }
 
 
 void MacroAssembler::StoreRoot(Register source,
                                Heap::RootListIndex index,
                                Condition cond) {
   str(source, MemOperand(roots, index << kPointerSizeLog2), cond);
 }
 
 
-void MacroAssembler::RecordWriteHelper(Register object,
-                                       Register address,
-                                       Register scratch) {
-  if (emit_debug_code()) {
-    // Check that the object is not in new space.
-    Label not_in_new_space;
-    InNewSpace(object, scratch, ne, &not_in_new_space);
-    Abort("new-space object passed to RecordWriteHelper");
-    bind(&not_in_new_space);
-  }
-
-  // Calculate page address.
-  Bfc(object, 0, kPageSizeBits);
-
-  // Calculate region number.
-  Ubfx(address, address, Page::kRegionSizeLog2,
-       kPageSizeBits - Page::kRegionSizeLog2);
-
-  // Mark region dirty.
-  ldr(scratch, MemOperand(object, Page::kDirtyFlagOffset));
-  mov(ip, Operand(1));
-  orr(scratch, scratch, Operand(ip, LSL, address));
-  str(scratch, MemOperand(object, Page::kDirtyFlagOffset));
-}
-
-
 void MacroAssembler::InNewSpace(Register object,
                                 Register scratch,
                                 Condition cond,
                                 Label* branch) {
   ASSERT(cond == eq || cond == ne);
   and_(scratch, object, Operand(ExternalReference::new_space_mask(isolate())));
   cmp(scratch, Operand(ExternalReference::new_space_start(isolate())));
   b(cond, branch);
 }
 
 
-// Will clobber 4 registers: object, offset, scratch, ip.  The
-// register 'object' contains a heap object pointer.  The heap object
-// tag is shifted away.
-void MacroAssembler::RecordWrite(Register object,
-                                 Operand offset,
-                                 Register scratch0,
-                                 Register scratch1) {
-  // The compiled code assumes that record write doesn't change the
-  // context register, so we check that none of the clobbered
-  // registers are cp.
-  ASSERT(!object.is(cp) && !scratch0.is(cp) && !scratch1.is(cp));
-
+void MacroAssembler::RecordWriteField(
+    Register object,
+    int offset,
+    Register value,
+    Register dst,
+    LinkRegisterStatus lr_status,
+    SaveFPRegsMode save_fp,
+    RememberedSetAction remembered_set_action,
+    SmiCheck smi_check) {
+  // First, check if a write barrier is even needed. The tests below
+  // catch stores of Smis.
   Label done;
 
-  // First, test that the object is not in the new space.  We cannot set
-  // region marks for new space pages.
-  InNewSpace(object, scratch0, eq, &done);
+  // Skip barrier if writing a smi.
+  if (smi_check == INLINE_SMI_CHECK) {
+    JumpIfSmi(value, &done);
+  }
 
-  // Add offset into the object.
-  add(scratch0, object, offset);
+  // Although the object register is tagged, the offset is relative to the start
+  // of the object, so so offset must be a multiple of kPointerSize.
+  ASSERT(IsAligned(offset, kPointerSize));
 
-  // Record the actual write.
-  RecordWriteHelper(object, scratch0, scratch1);
+  add(dst, object, Operand(offset - kHeapObjectTag));
+  if (emit_debug_code()) {
+    Label ok;
+    tst(dst, Operand((1 << kPointerSizeLog2) - 1));
+    b(eq, &ok);
+    stop("Unaligned cell in write barrier");
+    bind(&ok);
+  }
+
+  RecordWrite(object,
+              dst,
+              value,
+              lr_status,
+              save_fp,
+              remembered_set_action,
+              OMIT_SMI_CHECK);
 
   bind(&done);
 
-  // Clobber all input registers when running with the debug-code flag
+  // Clobber clobbered input registers when running with the debug-code flag
   // turned on to provoke errors.
   if (emit_debug_code()) {
-    mov(object, Operand(BitCast<int32_t>(kZapValue)));
-    mov(scratch0, Operand(BitCast<int32_t>(kZapValue)));
-    mov(scratch1, Operand(BitCast<int32_t>(kZapValue)));
+    mov(value, Operand(BitCast<int32_t>(kZapValue + 4)));
+    mov(dst, Operand(BitCast<int32_t>(kZapValue + 8)));
   }
 }
 
 
 // Will clobber 4 registers: object, address, scratch, ip.  The
 // register 'object' contains a heap object pointer.  The heap object
 // tag is shifted away.
 void MacroAssembler::RecordWrite(Register object,
                                  Register address,
-                                 Register scratch) {
+                                 Register value,
+                                 LinkRegisterStatus lr_status,
+                                 SaveFPRegsMode fp_mode,
+                                 RememberedSetAction remembered_set_action,
+                                 SmiCheck smi_check) {
   // The compiled code assumes that record write doesn't change the
   // context register, so we check that none of the clobbered
   // registers are cp.
-  ASSERT(!object.is(cp) && !address.is(cp) && !scratch.is(cp));
+  ASSERT(!address.is(cp) && !value.is(cp));
 
   Label done;
 
-  // First, test that the object is not in the new space.  We cannot set
-  // region marks for new space pages.
-  InNewSpace(object, scratch, eq, &done);
+  if (smi_check == INLINE_SMI_CHECK) {
+    ASSERT_EQ(0, kSmiTag);
+    tst(value, Operand(kSmiTagMask));
+    b(eq, &done);
+  }
+
+  CheckPageFlag(value,
+                value,  // Used as scratch.
+                MemoryChunk::kPointersToHereAreInterestingMask,
+                eq,
+                &done);
+  CheckPageFlag(object,
+                value,  // Used as scratch.
+                MemoryChunk::kPointersFromHereAreInterestingMask,
+                eq,
+                &done);
 
   // Record the actual write.
-  RecordWriteHelper(object, address, scratch);
+  if (lr_status == kLRHasNotBeenSaved) {
+    push(lr);
+  }
+  RecordWriteStub stub(object, value, address, remembered_set_action, fp_mode);
+  CallStub(&stub);
+  if (lr_status == kLRHasNotBeenSaved) {
+    pop(lr);
+  }
 
   bind(&done);
 
-  // Clobber all input registers when running with the debug-code flag
+  // Clobber clobbered registers when running with the debug-code flag
   // turned on to provoke errors.
   if (emit_debug_code()) {
-    mov(object, Operand(BitCast<int32_t>(kZapValue)));
-    mov(address, Operand(BitCast<int32_t>(kZapValue)));
-    mov(scratch, Operand(BitCast<int32_t>(kZapValue)));
+    mov(address, Operand(BitCast<int32_t>(kZapValue + 12)));
+    mov(value, Operand(BitCast<int32_t>(kZapValue + 16)));
+  }
+}
+
+
+void MacroAssembler::RememberedSetHelper(Register object,  // For debug tests.
+                                         Register address,
+                                         Register scratch,
+                                         SaveFPRegsMode fp_mode,
+                                         RememberedSetFinalAction and_then) {
+  Label done;
+  if (FLAG_debug_code) {
+    Label ok;
+    JumpIfNotInNewSpace(object, scratch, &ok);
+    stop("Remembered set pointer is in new space");
+    bind(&ok);
+  }
+  // Load store buffer top.
+  ExternalReference store_buffer =
+      ExternalReference::store_buffer_top(isolate());
+  mov(ip, Operand(store_buffer));
+  ldr(scratch, MemOperand(ip));
+  // Store pointer to buffer and increment buffer top.
+  str(address, MemOperand(scratch, kPointerSize, PostIndex));
+  // Write back new top of buffer.
+  str(scratch, MemOperand(ip));
+  // Call stub on end of buffer.
+  // Check for end of buffer.
+  tst(scratch, Operand(StoreBuffer::kStoreBufferOverflowBit));
+  if (and_then == kFallThroughAtEnd) {
+    b(eq, &done);
+  } else {
+    ASSERT(and_then == kReturnAtEnd);
+    Ret(ne);
+  }
+  push(lr);
+  StoreBufferOverflowStub store_buffer_overflow =
+      StoreBufferOverflowStub(fp_mode);
+  CallStub(&store_buffer_overflow);
+  pop(lr);
+  bind(&done);
+  if (and_then == kReturnAtEnd) {
+    Ret();
   }
 }
 
 
 // Push and pop all registers that can hold pointers.
 void MacroAssembler::PushSafepointRegisters() {
   // Safepoints expect a block of contiguous register values starting with r0:
   ASSERT(((1 << kNumSafepointSavedRegisters) - 1) == kSafepointSavedRegisters);
   // Safepoints expect a block of kNumSafepointRegisters values on the
   // stack, so adjust the stack for unsaved registers.
@@ skipping 434 matching lines @@
   }
 }
 
 
 void MacroAssembler::InvokeCode(Register code,
                                 const ParameterCount& expected,
                                 const ParameterCount& actual,
                                 InvokeFlag flag,
                                 const CallWrapper& call_wrapper,
                                 CallKind call_kind) {
+  // You can't call a function without a valid frame.
+  ASSERT(flag == JUMP_FUNCTION || has_frame());
+
   Label done;
 
   InvokePrologue(expected, actual, Handle<Code>::null(), code, &done, flag,
                  call_wrapper, call_kind);
   if (flag == CALL_FUNCTION) {
     call_wrapper.BeforeCall(CallSize(code));
     SetCallKind(r5, call_kind);
     Call(code);
     call_wrapper.AfterCall();
   } else {
     ASSERT(flag == JUMP_FUNCTION);
     SetCallKind(r5, call_kind);
     Jump(code);
   }
 
   // Continue here if InvokePrologue does handle the invocation due to
   // mismatched parameter counts.
   bind(&done);
 }
 
 
 void MacroAssembler::InvokeCode(Handle<Code> code,
                                 const ParameterCount& expected,
                                 const ParameterCount& actual,
                                 RelocInfo::Mode rmode,
                                 InvokeFlag flag,
                                 CallKind call_kind) {
+  // You can't call a function without a valid frame.
+  ASSERT(flag == JUMP_FUNCTION || has_frame());
+
   Label done;
 
   InvokePrologue(expected, actual, code, no_reg, &done, flag,
                  NullCallWrapper(), call_kind);
   if (flag == CALL_FUNCTION) {
     SetCallKind(r5, call_kind);
     Call(code, rmode);
   } else {
     SetCallKind(r5, call_kind);
     Jump(code, rmode);
   }
 
   // Continue here if InvokePrologue does handle the invocation due to
   // mismatched parameter counts.
   bind(&done);
 }
 
 
 void MacroAssembler::InvokeFunction(Register fun,
                                     const ParameterCount& actual,
                                     InvokeFlag flag,
                                     const CallWrapper& call_wrapper,
                                     CallKind call_kind) {
+  // You can't call a function without a valid frame.
+  ASSERT(flag == JUMP_FUNCTION || has_frame());
+
   // Contract with called JS functions requires that function is passed in r1.
   ASSERT(fun.is(r1));
 
   Register expected_reg = r2;
   Register code_reg = r3;
 
   ldr(code_reg, FieldMemOperand(r1, JSFunction::kSharedFunctionInfoOffset));
   ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset));
   ldr(expected_reg,
       FieldMemOperand(code_reg,
                       SharedFunctionInfo::kFormalParameterCountOffset));
   mov(expected_reg, Operand(expected_reg, ASR, kSmiTagSize));
   ldr(code_reg,
       FieldMemOperand(r1, JSFunction::kCodeEntryOffset));
 
   ParameterCount expected(expected_reg);
   InvokeCode(code_reg, expected, actual, flag, call_wrapper, call_kind);
 }
 
 
 void MacroAssembler::InvokeFunction(JSFunction* function,
                                     const ParameterCount& actual,
                                     InvokeFlag flag,
                                     CallKind call_kind) {
+  // You can't call a function without a valid frame.
+  ASSERT(flag == JUMP_FUNCTION || has_frame());
+
   ASSERT(function->is_compiled());
 
   // Get the function and setup the context.
   mov(r1, Operand(Handle<JSFunction>(function)));
   ldr(cp, FieldMemOperand(r1, JSFunction::kContextOffset));
 
   // Invoke the cached code.
   Handle<Code> code(function->code());
   ParameterCount expected(function->shared()->formal_parameter_count());
   if (V8::UseCrankshaft()) {
@@ skipping 35 matching lines @@
 
   ldr(scratch, FieldMemOperand(object, HeapObject::kMapOffset));
   ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
   tst(scratch, Operand(kIsNotStringMask));
   b(ne, fail);
 }
 
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
 void MacroAssembler::DebugBreak() {
-  ASSERT(allow_stub_calls());
   mov(r0, Operand(0, RelocInfo::NONE));
   mov(r1, Operand(ExternalReference(Runtime::kDebugBreak, isolate())));
   CEntryStub ces(1);
+  ASSERT(AllowThisStubCall(&ces));
   Call(ces.GetCode(), RelocInfo::DEBUG_BREAK);
 }
 #endif
 
 
 void MacroAssembler::PushTryHandler(CodeLocation try_location,
                                     HandlerType type) {
   // Adjust this code if not the case.
   STATIC_ASSERT(StackHandlerConstants::kSize == 5 * kPointerSize);
   STATIC_ASSERT(StackHandlerConstants::kNextOffset == 0 * kPointerSize);
@@ skipping 679 matching lines @@
                                  Heap::RootListIndex index) {
   ASSERT(!obj.is(ip));
   LoadRoot(ip, index);
   cmp(obj, ip);
 }
 
 
 void MacroAssembler::CheckFastElements(Register map,
                                        Register scratch,
                                        Label* fail) {
-  STATIC_ASSERT(FAST_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_ELEMENTS == 1);
   ldrb(scratch, FieldMemOperand(map, Map::kBitField2Offset));
   cmp(scratch, Operand(Map::kMaximumBitField2FastElementValue));
   b(hi, fail);
 }
 
 
+void MacroAssembler::CheckFastObjectElements(Register map,
+                                             Register scratch,
+                                             Label* fail) {
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
+  STATIC_ASSERT(FAST_ELEMENTS == 1);
+  ldrb(scratch, FieldMemOperand(map, Map::kBitField2Offset));
+  cmp(scratch, Operand(Map::kMaximumBitField2FastSmiOnlyElementValue));
+  b(ls, fail);
+  cmp(scratch, Operand(Map::kMaximumBitField2FastElementValue));
+  b(hi, fail);
+}
+
+
+void MacroAssembler::CheckFastSmiOnlyElements(Register map,
+                                              Register scratch,
+                                              Label* fail) {
+  STATIC_ASSERT(FAST_SMI_ONLY_ELEMENTS == 0);
+  ldrb(scratch, FieldMemOperand(map, Map::kBitField2Offset));
+  cmp(scratch, Operand(Map::kMaximumBitField2FastSmiOnlyElementValue));
+  b(hi, fail);
+}
+
+
 void MacroAssembler::CheckMap(Register obj,
                               Register scratch,
                               Handle<Map> map,
                               Label* fail,
                               SmiCheckType smi_check_type) {
   if (smi_check_type == DO_SMI_CHECK) {
     JumpIfSmi(obj, fail);
   }
   ldr(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
   mov(ip, Operand(map));
@@ skipping 75 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(AllowThisStubCall(stub));  // Stub calls are not allowed in some stubs.
   Call(stub->GetCode(), RelocInfo::CODE_TARGET, kNoASTId, cond);
 }
 
 
 MaybeObject* MacroAssembler::TryCallStub(CodeStub* stub, Condition cond) {
-  ASSERT(allow_stub_calls());  // Stub calls are not allowed in some stubs.
+  ASSERT(AllowThisStubCall(stub));  // Stub calls are not allowed in some stubs.
   Object* result;
   { MaybeObject* maybe_result = stub->TryGetCode();
     if (!maybe_result->ToObject(&result)) return maybe_result;
   }
   Handle<Code> code(Code::cast(result));
   Call(code, RelocInfo::CODE_TARGET, kNoASTId, cond);
   return result;
 }
 
 
 void MacroAssembler::TailCallStub(CodeStub* stub, Condition cond) {
-  ASSERT(allow_stub_calls());  // Stub calls are not allowed in some stubs.
+  ASSERT(allow_stub_calls_ || stub->CompilingCallsToThisStubIsGCSafe());
   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(Handle<Code>(Code::cast(result)), RelocInfo::CODE_TARGET, cond);
   return result;
 }
 
 
 static int AddressOffset(ExternalReference ref0, ExternalReference ref1) {
@@ skipping 82 matching lines @@
   mov(r0, Operand(ExternalReference::isolate_address()));
   CallCFunction(
       ExternalReference::delete_handle_scope_extensions(isolate()), 1);
   mov(r0, r4);
   jmp(&leave_exit_frame);
 
   return result;
 }
 
 
+bool MacroAssembler::AllowThisStubCall(CodeStub* stub) {
+  if (!has_frame_ && stub->SometimesSetsUpAFrame()) return false;
+  return allow_stub_calls_ || stub->CompilingCallsToThisStubIsGCSafe();
+}
+
+
 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 375 matching lines @@
 
 void MacroAssembler::CallRuntime(Runtime::FunctionId fid, int num_arguments) {
   CallRuntime(Runtime::FunctionForId(fid), num_arguments);
 }
 
 
 void MacroAssembler::CallRuntimeSaveDoubles(Runtime::FunctionId id) {
   const Runtime::Function* function = Runtime::FunctionForId(id);
   mov(r0, Operand(function->nargs));
   mov(r1, Operand(ExternalReference(function, isolate())));
-  CEntryStub stub(1);
-  stub.SaveDoubles();
+  CEntryStub stub(1, kSaveFPRegs);
   CallStub(&stub);
 }
 
 
 void MacroAssembler::CallExternalReference(const ExternalReference& ext,
                                            int num_arguments) {
   mov(r0, Operand(num_arguments));
   mov(r1, Operand(ext));
 
   CEntryStub stub(1);
@@ skipping 52 matching lines @@
 #endif
   mov(r1, Operand(builtin));
   CEntryStub stub(1);
   return TryTailCallStub(&stub);
 }
 
 
 void MacroAssembler::InvokeBuiltin(Builtins::JavaScript id,
                                    InvokeFlag flag,
                                    const CallWrapper& call_wrapper) {
+  // You can't call a builtin without a valid frame.
+  ASSERT(flag == JUMP_FUNCTION || has_frame());
+
   GetBuiltinEntry(r2, id);
   if (flag == CALL_FUNCTION) {
     call_wrapper.BeforeCall(CallSize(r2));
     SetCallKind(r5, CALL_AS_METHOD);
     Call(r2);
     call_wrapper.AfterCall();
   } else {
     ASSERT(flag == JUMP_FUNCTION);
     SetCallKind(r5, CALL_AS_METHOD);
     Jump(r2);
@@ skipping 111 matching lines @@
   // from the real pointer as a smi.
   intptr_t p1 = reinterpret_cast<intptr_t>(msg);
   intptr_t p0 = (p1 & ~kSmiTagMask) + kSmiTag;
   ASSERT(reinterpret_cast<Object*>(p0)->IsSmi());
 #ifdef DEBUG
   if (msg != NULL) {
     RecordComment("Abort message: ");
     RecordComment(msg);
   }
 #endif
-  // Disable stub call restrictions to always allow calls to abort.
-  AllowStubCallsScope allow_scope(this, true);
 
   mov(r0, Operand(p0));
   push(r0);
   mov(r0, Operand(Smi::FromInt(p1 - p0)));
   push(r0);
-  CallRuntime(Runtime::kAbort, 2);
+  // Disable stub call restrictions to always allow calls to abort.
+  if (!has_frame_) {
+    // We don't actually want to generate a pile of code for this, so just
+    // claim there is a stack frame, without generating one.
+    FrameScope scope(this, StackFrame::NONE);
+    CallRuntime(Runtime::kAbort, 2);
+  } else {
+    CallRuntime(Runtime::kAbort, 2);
+  }
   // will not return here
   if (is_const_pool_blocked()) {
     // If the calling code cares about the exact number of
     // instructions generated, we insert padding here to keep the size
     // of the Abort macro constant.
     static const int kExpectedAbortInstructions = 10;
     int abort_instructions = InstructionsGeneratedSince(&abort_start);
     ASSERT(abort_instructions <= kExpectedAbortInstructions);
     while (abort_instructions++ < kExpectedAbortInstructions) {
       nop();
@@ skipping 280 matching lines @@
   b(eq, &done);
   bind(&byte_loop_1);
   ldrb(scratch, MemOperand(src, 1, PostIndex));
   strb(scratch, MemOperand(dst, 1, PostIndex));
   sub(length, length, Operand(1), SetCC);
   b(ne, &byte_loop_1);
   bind(&done);
 }
 
 
+void MacroAssembler::InitializeFieldsWithFiller(Register start_offset,
+                                                Register end_offset,
+                                                Register filler) {
+  Label loop, entry;
+  b(&entry);
+  bind(&loop);
+  str(filler, MemOperand(start_offset, kPointerSize, PostIndex));
+  bind(&entry);
+  cmp(start_offset, end_offset);
+  b(lt, &loop);
+}
+
+
 void MacroAssembler::CountLeadingZeros(Register zeros,   // Answer.
                                        Register source,  // Input.
                                        Register scratch) {
   ASSERT(!zeros.is(source) || !source.is(scratch));
   ASSERT(!zeros.is(scratch));
   ASSERT(!scratch.is(ip));
   ASSERT(!source.is(ip));
   ASSERT(!zeros.is(ip));
 #ifdef CAN_USE_ARMV5_INSTRUCTIONS
   clz(zeros, source);  // This instruction is only supported after ARM5.
@@ skipping 139 matching lines @@
   } else {
     Move(r2, reg);
     vmov(r0, r1, dreg);
   }
 }
 
 
 void MacroAssembler::CallCFunction(ExternalReference function,
                                    int num_reg_arguments,
                                    int num_double_arguments) {
-  CallCFunctionHelper(no_reg,
-                      function,
-                      ip,
-                      num_reg_arguments,
-                      num_double_arguments);
+  mov(ip, Operand(function));
+  CallCFunctionHelper(ip, num_reg_arguments, num_double_arguments);
 }
 
 
 void MacroAssembler::CallCFunction(Register function,
-                                     Register scratch,
-                                     int num_reg_arguments,
-                                     int num_double_arguments) {
-  CallCFunctionHelper(function,
-                      ExternalReference::the_hole_value_location(isolate()),
-                      scratch,
-                      num_reg_arguments,
-                      num_double_arguments);
+                                   int num_reg_arguments,
+                                   int num_double_arguments) {
+  CallCFunctionHelper(function, num_reg_arguments, num_double_arguments);
 }
 
 
 void MacroAssembler::CallCFunction(ExternalReference function,
                                    int num_arguments) {
   CallCFunction(function, num_arguments, 0);
 }
 
 
 void MacroAssembler::CallCFunction(Register function,
-                                   Register scratch,
                                    int num_arguments) {
-  CallCFunction(function, scratch, num_arguments, 0);
+  CallCFunction(function, num_arguments, 0);
 }
 
 
 void MacroAssembler::CallCFunctionHelper(Register function,
-                                         ExternalReference function_reference,
-                                         Register scratch,
                                          int num_reg_arguments,
                                          int num_double_arguments) {
+  ASSERT(has_frame());
   // Make sure that the stack is aligned before calling a C function unless
   // running in the simulator. The simulator has its own alignment check which
   // provides more information.
 #if defined(V8_HOST_ARCH_ARM)
   if (emit_debug_code()) {
     int frame_alignment = OS::ActivationFrameAlignment();
     int frame_alignment_mask = frame_alignment - 1;
     if (frame_alignment > kPointerSize) {
       ASSERT(IsPowerOf2(frame_alignment));
       Label alignment_as_expected;
       tst(sp, Operand(frame_alignment_mask));
       b(eq, &alignment_as_expected);
       // Don't use Check here, as it will call Runtime_Abort possibly
       // re-entering here.
       stop("Unexpected alignment");
       bind(&alignment_as_expected);
     }
   }
 #endif
 
   // Just call directly. The function called cannot cause a GC, or
   // allow preemption, so the return address in the link register
   // stays correct.
-  if (function.is(no_reg)) {
-    mov(scratch, Operand(function_reference));
-    function = scratch;
-  }
   Call(function);
   int stack_passed_arguments = CalculateStackPassedWords(
       num_reg_arguments, num_double_arguments);
   if (ActivationFrameAlignment() > kPointerSize) {
     ldr(sp, MemOperand(sp, stack_passed_arguments * kPointerSize));
   } else {
     add(sp, sp, Operand(stack_passed_arguments * sizeof(kPointerSize)));
   }
 }
 
@@ skipping 11 matching lines @@
     // Result was clobbered. Restore it.
     ldr(result, MemOperand(ldr_location));
   }
   // Get the address of the constant.
   and_(result, result, Operand(kLdrOffsetMask));
   add(result, ldr_location, Operand(result));
   add(result, result, Operand(kPCRegOffset));
 }
 
 
+void MacroAssembler::CheckPageFlag(
+    Register object,
+    Register scratch,
+    int mask,
+    Condition cc,
+    Label* condition_met) {
+  and_(scratch, object, Operand(~Page::kPageAlignmentMask));
+  ldr(scratch, MemOperand(scratch, MemoryChunk::kFlagsOffset));
+  tst(scratch, Operand(mask));
+  b(cc, condition_met);
+}
+
+
+void MacroAssembler::JumpIfBlack(Register object,
+                                 Register scratch0,
+                                 Register scratch1,
+                                 Label* on_black) {
+  HasColor(object, scratch0, scratch1, on_black, 1, 0);  // kBlackBitPattern.
+  ASSERT(strcmp(Marking::kBlackBitPattern, "10") == 0);
+}
+
+
+void MacroAssembler::HasColor(Register object,
+                              Register bitmap_scratch,
+                              Register mask_scratch,
+                              Label* has_color,
+                              int first_bit,
+                              int second_bit) {
+  ASSERT(!AreAliased(object, bitmap_scratch, mask_scratch, no_reg));
+
+  GetMarkBits(object, bitmap_scratch, mask_scratch);
+
+  Label other_color, word_boundary;
+  ldr(ip, MemOperand(bitmap_scratch, MemoryChunk::kHeaderSize));
+  tst(ip, Operand(mask_scratch));
+  b(first_bit == 1 ? eq : ne, &other_color);
+  // Shift left 1 by adding.
+  add(mask_scratch, mask_scratch, Operand(mask_scratch), SetCC);
+  b(eq, &word_boundary);
+  tst(ip, Operand(mask_scratch));
+  b(second_bit == 1 ? ne : eq, has_color);
+  jmp(&other_color);
+
+  bind(&word_boundary);
+  ldr(ip, MemOperand(bitmap_scratch, MemoryChunk::kHeaderSize + kPointerSize));
+  tst(ip, Operand(1));
+  b(second_bit == 1 ? ne : eq, has_color);
+  bind(&other_color);
+}
+
+
+// Detect some, but not all, common pointer-free objects.  This is used by the
+// incremental write barrier which doesn't care about oddballs (they are always
+// marked black immediately so this code is not hit).
+void MacroAssembler::JumpIfDataObject(Register value,
+                                      Register scratch,
+                                      Label* not_data_object) {
+  Label is_data_object;
+  ldr(scratch, FieldMemOperand(value, HeapObject::kMapOffset));
+  CompareRoot(scratch, Heap::kHeapNumberMapRootIndex);
+  b(eq, &is_data_object);
+  ASSERT(kIsIndirectStringTag == 1 && kIsIndirectStringMask == 1);
+  ASSERT(kNotStringTag == 0x80 && kIsNotStringMask == 0x80);
+  // If it's a string and it's not a cons string then it's an object containing
+  // no GC pointers.
+  ldrb(scratch, FieldMemOperand(scratch, Map::kInstanceTypeOffset));
+  tst(scratch, Operand(kIsIndirectStringMask | kIsNotStringMask));
+  b(ne, not_data_object);
+  bind(&is_data_object);
+}
+
+
+void MacroAssembler::GetMarkBits(Register addr_reg,
+                                 Register bitmap_reg,
+                                 Register mask_reg) {
+  ASSERT(!AreAliased(addr_reg, bitmap_reg, mask_reg, no_reg));
+  and_(bitmap_reg, addr_reg, Operand(~Page::kPageAlignmentMask));
+  Ubfx(mask_reg, addr_reg, kPointerSizeLog2, Bitmap::kBitsPerCellLog2);
+  const int kLowBits = kPointerSizeLog2 + Bitmap::kBitsPerCellLog2;
+  Ubfx(ip, addr_reg, kLowBits, kPageSizeBits - kLowBits);
+  add(bitmap_reg, bitmap_reg, Operand(ip, LSL, kPointerSizeLog2));
+  mov(ip, Operand(1));
+  mov(mask_reg, Operand(ip, LSL, mask_reg));
+}
+
+
+void MacroAssembler::EnsureNotWhite(
+    Register value,
+    Register bitmap_scratch,
+    Register mask_scratch,
+    Register load_scratch,
+    Label* value_is_white_and_not_data) {
+  ASSERT(!AreAliased(value, bitmap_scratch, mask_scratch, ip));
+  GetMarkBits(value, bitmap_scratch, mask_scratch);
+
+  // If the value is black or grey we don't need to do anything.
+  ASSERT(strcmp(Marking::kWhiteBitPattern, "00") == 0);
+  ASSERT(strcmp(Marking::kBlackBitPattern, "10") == 0);
+  ASSERT(strcmp(Marking::kGreyBitPattern, "11") == 0);
+  ASSERT(strcmp(Marking::kImpossibleBitPattern, "01") == 0);
+
+  Label done;
+
+  // Since both black and grey have a 1 in the first position and white does
+  // not have a 1 there we only need to check one bit.
+  ldr(load_scratch, MemOperand(bitmap_scratch, MemoryChunk::kHeaderSize));
+  tst(mask_scratch, load_scratch);
+  b(ne, &done);
+
+  if (FLAG_debug_code) {
+    // Check for impossible bit pattern.
+    Label ok;
+    // LSL may overflow, making the check conservative.
+    tst(load_scratch, Operand(mask_scratch, LSL, 1));
+    b(eq, &ok);
+    stop("Impossible marking bit pattern");
+    bind(&ok);
+  }
+
+  // Value is white.  We check whether it is data that doesn't need scanning.
+  // Currently only checks for HeapNumber and non-cons strings.
+  Register map = load_scratch;  // Holds map while checking type.
+  Register length = load_scratch;  // Holds length of object after testing type.
+  Label is_data_object;
+
+  // Check for heap-number
+  ldr(map, FieldMemOperand(value, HeapObject::kMapOffset));
+  CompareRoot(map, Heap::kHeapNumberMapRootIndex);
+  mov(length, Operand(HeapNumber::kSize), LeaveCC, eq);
+  b(eq, &is_data_object);
+
+  // Check for strings.
+  ASSERT(kIsIndirectStringTag == 1 && kIsIndirectStringMask == 1);
+  ASSERT(kNotStringTag == 0x80 && kIsNotStringMask == 0x80);
+  // If it's a string and it's not a cons string then it's an object containing
+  // no GC pointers.
+  Register instance_type = load_scratch;
+  ldrb(instance_type, FieldMemOperand(map, Map::kInstanceTypeOffset));
+  tst(instance_type, Operand(kIsIndirectStringMask | kIsNotStringMask));
+  b(ne, value_is_white_and_not_data);
+  // It's a non-indirect (non-cons and non-slice) string.
+  // If it's external, the length is just ExternalString::kSize.
+  // Otherwise it's String::kHeaderSize + string->length() * (1 or 2).
+  // External strings are the only ones with the kExternalStringTag bit
+  // set.
+  ASSERT_EQ(0, kSeqStringTag & kExternalStringTag);
+  ASSERT_EQ(0, kConsStringTag & kExternalStringTag);
+  tst(instance_type, Operand(kExternalStringTag));
+  mov(length, Operand(ExternalString::kSize), LeaveCC, ne);
+  b(ne, &is_data_object);
+
+  // Sequential string, either ASCII or UC16.
+  // For ASCII (char-size of 1) we shift the smi tag away to get the length.
+  // For UC16 (char-size of 2) we just leave the smi tag in place, thereby
+  // getting the length multiplied by 2.
+  ASSERT(kAsciiStringTag == 4 && kStringEncodingMask == 4);
+  ASSERT(kSmiTag == 0 && kSmiTagSize == 1);
+  ldr(ip, FieldMemOperand(value, String::kLengthOffset));
+  tst(instance_type, Operand(kStringEncodingMask));
+  mov(ip, Operand(ip, LSR, 1), LeaveCC, ne);
+  add(length, ip, Operand(SeqString::kHeaderSize + kObjectAlignmentMask));
+  and_(length, length, Operand(~kObjectAlignmentMask));
+
+  bind(&is_data_object);
+  // Value is a data object, and it is white.  Mark it black.  Since we know
+  // that the object is white we can make it black by flipping one bit.
+  ldr(ip, MemOperand(bitmap_scratch, MemoryChunk::kHeaderSize));
+  orr(ip, ip, Operand(mask_scratch));
+  str(ip, MemOperand(bitmap_scratch, MemoryChunk::kHeaderSize));
+
+  and_(bitmap_scratch, bitmap_scratch, Operand(~Page::kPageAlignmentMask));
+  ldr(ip, MemOperand(bitmap_scratch, MemoryChunk::kLiveBytesOffset));
+  add(ip, ip, Operand(length));
+  str(ip, MemOperand(bitmap_scratch, MemoryChunk::kLiveBytesOffset));
+
+  bind(&done);
+}
+
+
 void MacroAssembler::ClampUint8(Register output_reg, Register input_reg) {
   Usat(output_reg, 8, Operand(input_reg));
 }
 
 
 void MacroAssembler::ClampDoubleToUint8(Register result_reg,
                                         DoubleRegister input_reg,
                                         DoubleRegister temp_double_reg) {
   Label above_zero;
   Label done;
@@ skipping 29 matching lines @@
                                              Register descriptors) {
   ldr(descriptors,
       FieldMemOperand(map, Map::kInstanceDescriptorsOrBitField3Offset));
   Label not_smi;
   JumpIfNotSmi(descriptors, &not_smi);
   mov(descriptors, Operand(FACTORY->empty_descriptor_array()));
   bind(&not_smi);
 }
 
 
+bool AreAliased(Register r1, Register r2, Register r3, Register r4) {
+  if (r1.is(r2)) return true;
+  if (r1.is(r3)) return true;
+  if (r1.is(r4)) return true;
+  if (r2.is(r3)) return true;
+  if (r2.is(r4)) return true;
+  if (r3.is(r4)) return true;
+  return false;
+}
+
+
 CodePatcher::CodePatcher(byte* address, int instructions)
     : address_(address),
       instructions_(instructions),
       size_(instructions * Assembler::kInstrSize),
       masm_(Isolate::Current(), address, size_ + Assembler::kGap) {
   // Create a new macro assembler pointing to the address of the code to patch.
   // The size is adjusted with kGap on order for the assembler to generate size
   // bytes of instructions without failing with buffer size constraints.
   ASSERT(masm_.reloc_info_writer.pos() == address_ + size_ + Assembler::kGap);
 }
@@ skipping 22 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