ARM: Implement DoInstanceOfKnownGlobal stub

BUG=none
TEST=none

Patch by Martyn Capewell from ARM Ltd.

Review URL: http://codereview.chromium.org/6248004


git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6403 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/code-stubs-arm.cc

@@ -2890,18 +2890,33 @@ void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
 }
 
 
-// Uses registers r0 to r4. Expected input is
-// object in r0 (or at sp+1*kPointerSize) and function in
-// r1 (or at sp), depending on whether or not
-// args_in_registers() is true.
+// Uses registers r0 to r4.
+// Expected input (depending on whether args are in registers or on the stack):
+// * object: r0 or at sp + 1 * kPointerSize.
+// * function: r1 or at sp.
+//
+// An inlined call site may have been generated before calling this stub.
+// In this case the offset to the inline site to patch is passed on the stack,
+// in the safepoint slot for register r4.
+// (See LCodeGen::DoInstanceOfKnownGlobal)
 void InstanceofStub::Generate(MacroAssembler* masm) {
+  // Call site inlining and patching implies arguments in registers.
+  ASSERT(HasArgsInRegisters() || !HasCallSiteInlineCheck());
+  // ReturnTrueFalse is only implemented for inlined call sites.
+  ASSERT(!ReturnTrueFalseObject() || HasCallSiteInlineCheck());
+
   // Fixed register usage throughout the stub:
   const Register object = r0;  // Object (lhs).
-  const Register map = r3;  // Map of the object.
+  Register map = r3;  // Map of the object.
   const Register function = r1;  // Function (rhs).
   const Register prototype = r4;  // Prototype of the function.
+  const Register inline_site = r9;
   const Register scratch = r2;
+
+  const int32_t kDeltaToLoadBoolResult = 3 * kPointerSize;
+
   Label slow, loop, is_instance, is_not_instance, not_js_object;
+
   if (!HasArgsInRegisters()) {
     __ ldr(object, MemOperand(sp, 1 * kPointerSize));
     __ ldr(function, MemOperand(sp, 0));
@@ -2911,50 +2926,100 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
   __ BranchOnSmi(object, &not_js_object);
   __ IsObjectJSObjectType(object, map, scratch, &not_js_object);
 
-  // Look up the function and the map in the instanceof cache.
-  Label miss;
-  __ LoadRoot(ip, Heap::kInstanceofCacheFunctionRootIndex);
-  __ cmp(function, ip);
-  __ b(ne, &miss);
-  __ LoadRoot(ip, Heap::kInstanceofCacheMapRootIndex);
-  __ cmp(map, ip);
-  __ b(ne, &miss);
-  __ LoadRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
-  __ Ret(HasArgsInRegisters() ? 0 : 2);
+  // If there is a call site cache don't look in the global cache, but do the
+  // real lookup and update the call site cache.
+  if (!HasCallSiteInlineCheck()) {
+    Label miss;
+    __ LoadRoot(ip, Heap::kInstanceofCacheFunctionRootIndex);
+    __ cmp(function, ip);
+    __ b(ne, &miss);
+    __ LoadRoot(ip, Heap::kInstanceofCacheMapRootIndex);
+    __ cmp(map, ip);
+    __ b(ne, &miss);
+    __ LoadRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
+    __ Ret(HasArgsInRegisters() ? 0 : 2);
+
+    __ bind(&miss);
+  }
 
-  __ bind(&miss);
+  // Get the prototype of the function.
   __ TryGetFunctionPrototype(function, prototype, scratch, &slow);
 
   // Check that the function prototype is a JS object.
   __ BranchOnSmi(prototype, &slow);
   __ IsObjectJSObjectType(prototype, scratch, scratch, &slow);
 
-  __ StoreRoot(function, Heap::kInstanceofCacheFunctionRootIndex);
-  __ StoreRoot(map, Heap::kInstanceofCacheMapRootIndex);
+  // Update the global instanceof or call site inlined cache with the current
+  // map and function. The cached answer will be set when it is known below.
+  if (!HasCallSiteInlineCheck()) {
+    __ StoreRoot(function, Heap::kInstanceofCacheFunctionRootIndex);
+    __ StoreRoot(map, Heap::kInstanceofCacheMapRootIndex);
+  } else {
+    ASSERT(HasArgsInRegisters());
+    // Patch the (relocated) inlined map check.
+
+    // The offset was stored in r4 safepoint slot.
+    // (See LCodeGen::DoDeferredLInstanceOfKnownGlobal)
+    __ ldr(scratch, MacroAssembler::SafepointRegisterSlot(r4));
+    __ sub(inline_site, lr, scratch);
+    // Get the map location in scratch and patch it.
+    __ GetRelocatedValueLocation(inline_site, scratch);
+    __ str(map, MemOperand(scratch));
+  }
 
   // Register mapping: r3 is object map and r4 is function prototype.
   // Get prototype of object into r2.
   __ ldr(scratch, FieldMemOperand(map, Map::kPrototypeOffset));
 
+  // We don't need map any more. Use it as a scratch register.
+  Register scratch2 = map;
+  map = no_reg;
+
   // Loop through the prototype chain looking for the function prototype.
+  __ LoadRoot(scratch2, Heap::kNullValueRootIndex);
   __ bind(&loop);
   __ cmp(scratch, Operand(prototype));
   __ b(eq, &is_instance);
-  __ LoadRoot(ip, Heap::kNullValueRootIndex);
-  __ cmp(scratch, ip);
+  __ cmp(scratch, scratch2);
   __ b(eq, &is_not_instance);
   __ ldr(scratch, FieldMemOperand(scratch, HeapObject::kMapOffset));
   __ ldr(scratch, FieldMemOperand(scratch, Map::kPrototypeOffset));
   __ jmp(&loop);
 
   __ bind(&is_instance);
-  __ mov(r0, Operand(Smi::FromInt(0)));
-  __ StoreRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
+  if (!HasCallSiteInlineCheck()) {
+    __ mov(r0, Operand(Smi::FromInt(0)));
+    __ StoreRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
+  } else {
+    // Patch the call site to return true.
+    __ LoadRoot(r0, Heap::kTrueValueRootIndex);
+    __ add(inline_site, inline_site, Operand(kDeltaToLoadBoolResult));
+    // Get the boolean result location in scratch and patch it.
+    __ GetRelocatedValueLocation(inline_site, scratch);
+    __ str(r0, MemOperand(scratch));
+
+    if (!ReturnTrueFalseObject()) {
+      __ mov(r0, Operand(Smi::FromInt(0)));
+    }
+  }
   __ Ret(HasArgsInRegisters() ? 0 : 2);
 
   __ bind(&is_not_instance);
-  __ mov(r0, Operand(Smi::FromInt(1)));
-  __ StoreRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
+  if (!HasCallSiteInlineCheck()) {
+    __ mov(r0, Operand(Smi::FromInt(1)));
+    __ StoreRoot(r0, Heap::kInstanceofCacheAnswerRootIndex);
+  } else {
+    // Patch the call site to return false.
+    __ LoadRoot(r0, Heap::kFalseValueRootIndex);
+    __ add(inline_site, inline_site, Operand(kDeltaToLoadBoolResult));
+    // Get the boolean result location in scratch and patch it.
+    __ GetRelocatedValueLocation(inline_site, scratch);
+    __ str(r0, MemOperand(scratch));
+
+    if (!ReturnTrueFalseObject()) {
+      __ mov(r0, Operand(Smi::FromInt(1)));
+    }
+  }
   __ Ret(HasArgsInRegisters() ? 0 : 2);
 
   Label object_not_null, object_not_null_or_smi;
@@ -2962,7 +3027,7 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
   // Before null, smi and string value checks, check that the rhs is a function
   // as for a non-function rhs an exception needs to be thrown.
   __ BranchOnSmi(function, &slow);
-  __ CompareObjectType(function, map, scratch, JS_FUNCTION_TYPE);
+  __ CompareObjectType(function, scratch2, scratch, JS_FUNCTION_TYPE);
   __ b(ne, &slow);
 
   // Null is not instance of anything.
@@ -2985,13 +3050,30 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
 
   // Slow-case.  Tail call builtin.
   __ bind(&slow);
-  if (HasArgsInRegisters()) {
+  if (!ReturnTrueFalseObject()) {
+    if (HasArgsInRegisters()) {
+      __ Push(r0, r1);
+    }
+  __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_JS);
+  } else {
+    __ EnterInternalFrame();
     __ Push(r0, r1);
+    __ InvokeBuiltin(Builtins::INSTANCE_OF, CALL_JS);
+    __ LeaveInternalFrame();
+    __ cmp(r0, Operand(0));
+    __ LoadRoot(r0, Heap::kTrueValueRootIndex, eq);
+    __ LoadRoot(r0, Heap::kFalseValueRootIndex, ne);
+    __ Ret(HasArgsInRegisters() ? 0 : 2);
   }
-  __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_JS);
 }
 
 
+Register InstanceofStub::left() { return r0; }
+
+
+Register InstanceofStub::right() { return r1; }
+
+
 void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* masm) {
   // The displacement is the offset of the last parameter (if any)
   // relative to the frame pointer.

src/arm/lithium-arm.cc

@@ -674,6 +674,12 @@ LInstruction* LChunkBuilder::MarkAsCall(LInstruction* instr,
 }
 
 
+LInstruction* LChunkBuilder::MarkAsSaveDoubles(LInstruction* instr) {
+  allocator_->MarkAsSaveDoubles();
+  return instr;
+}
+
+
 LInstruction* LChunkBuilder::AssignPointerMap(LInstruction* instr) {
   ASSERT(!instr->HasPointerMap());
   instr->set_pointer_map(new LPointerMap(position_));
@@ -1083,8 +1089,9 @@ LInstruction* LChunkBuilder::DoInstanceOf(HInstanceOf* instr) {
 LInstruction* LChunkBuilder::DoInstanceOfKnownGlobal(
     HInstanceOfKnownGlobal* instr) {
   LInstruction* result =
-      new LInstanceOfKnownGlobal(UseFixed(instr->value(), r0));
-  return MarkAsCall(DefineFixed(result, r0), instr);
+      new LInstanceOfKnownGlobal(UseFixed(instr->value(), r0), FixedTemp(r4));
+  MarkAsSaveDoubles(result);
+  return AssignEnvironment(AssignPointerMap(DefineFixed(result, r0)));
 }
 
 

src/arm/lithium-arm.h

@@ -945,14 +945,18 @@ class LInstanceOfAndBranch: public LInstanceOf {
 
 class LInstanceOfKnownGlobal: public LUnaryOperation {
  public:
-  explicit LInstanceOfKnownGlobal(LOperand* left)
-      : LUnaryOperation(left) { }
+  explicit LInstanceOfKnownGlobal(LOperand* left, LOperand* temp)
+      : LUnaryOperation(left), temp_(temp) { }
 
   DECLARE_CONCRETE_INSTRUCTION(InstanceOfKnownGlobal,
                                "instance-of-known-global")
   DECLARE_HYDROGEN_ACCESSOR(InstanceOfKnownGlobal)
 
   Handle<JSFunction> function() const { return hydrogen()->function(); }
+  LOperand* temp() const { return temp_; }
+
+ private:
+  LOperand* temp_;
 };
 
 
@@ -1927,6 +1931,7 @@ class LChunkBuilder BASE_EMBEDDED {
       LInstruction* instr,
       HInstruction* hinstr,
       CanDeoptimize can_deoptimize = CANNOT_DEOPTIMIZE_EAGERLY);
+  LInstruction* MarkAsSaveDoubles(LInstruction* instr);
 
   LInstruction* SetInstructionPendingDeoptimizationEnvironment(
       LInstruction* instr, int ast_id);

src/arm/lithium-codegen-arm.cc

@@ -1949,7 +1949,119 @@ void LCodeGen::DoInstanceOfAndBranch(LInstanceOfAndBranch* instr) {
 
 
 void LCodeGen::DoInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr) {
-  Abort("DoInstanceOfKnownGlobal unimplemented.");
+  class DeferredInstanceOfKnownGlobal: public LDeferredCode {
+   public:
+    DeferredInstanceOfKnownGlobal(LCodeGen* codegen,
+                                  LInstanceOfKnownGlobal* instr)
+        : LDeferredCode(codegen), instr_(instr) { }
+    virtual void Generate() {
+      codegen()->DoDeferredLInstanceOfKnownGlobal(instr_, &map_check_);
+    }
+
+    Label* map_check() { return &map_check_; }
+
+   private:
+    LInstanceOfKnownGlobal* instr_;
+    Label map_check_;
+  };
+
+  DeferredInstanceOfKnownGlobal* deferred;
+  deferred = new DeferredInstanceOfKnownGlobal(this, instr);
+
+  Label done, false_result;
+  Register object = ToRegister(instr->input());
+  Register temp = ToRegister(instr->temp());
+  Register result = ToRegister(instr->result());
+
+  ASSERT(object.is(r0));
+  ASSERT(result.is(r0));
+
+  // A Smi is not instance of anything.
+  __ BranchOnSmi(object, &false_result);
+
+  // This is the inlined call site instanceof cache. The two occurences of the
+  // hole value will be patched to the last map/result pair generated by the
+  // instanceof stub.
+  Label cache_miss;
+  Register map = temp;
+  __ ldr(map, FieldMemOperand(object, HeapObject::kMapOffset));
+  __ bind(deferred->map_check());  // Label for calculating code patching.
+  // We use Factory::the_hole_value() on purpose instead of loading from the
+  // root array to force relocation to be able to later patch with
+  // the cached map.
+  __ mov(ip, Operand(Factory::the_hole_value()));
+  __ cmp(map, Operand(ip));
+  __ b(ne, &cache_miss);
+  // We use Factory::the_hole_value() on purpose instead of loading from the
+  // root array to force relocation to be able to later patch
+  // with true or false.
+  __ mov(result, Operand(Factory::the_hole_value()));
+  __ b(&done);
+
+  // The inlined call site cache did not match. Check null and string before
+  // calling the deferred code.
+  __ bind(&cache_miss);
+  // Null is not instance of anything.
+  __ LoadRoot(ip, Heap::kNullValueRootIndex);
+  __ cmp(object, Operand(ip));
+  __ b(eq, &false_result);
+
+  // String values is not instance of anything.
+  Condition is_string = masm_->IsObjectStringType(object, temp);
+  __ b(is_string, &false_result);
+
+  // Go to the deferred code.
+  __ b(deferred->entry());
+
+  __ bind(&false_result);
+  __ LoadRoot(result, Heap::kFalseValueRootIndex);
+
+  // Here result has either true or false. Deferred code also produces true or
+  // false object.
+  __ bind(deferred->exit());
+  __ bind(&done);
+}
+
+
+void LCodeGen::DoDeferredLInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
+                                                Label* map_check) {
+  Register result = ToRegister(instr->result());
+  ASSERT(result.is(r0));
+
+  InstanceofStub::Flags flags = InstanceofStub::kNoFlags;
+  flags = static_cast<InstanceofStub::Flags>(
+      flags | InstanceofStub::kArgsInRegisters);
+  flags = static_cast<InstanceofStub::Flags>(
+      flags | InstanceofStub::kCallSiteInlineCheck);
+  flags = static_cast<InstanceofStub::Flags>(
+      flags | InstanceofStub::kReturnTrueFalseObject);
+  InstanceofStub stub(flags);
+
+  __ PushSafepointRegisters();
+
+  // Get the temp register reserved by the instruction. This needs to be r4 as
+  // its slot of the pushing of safepoint registers is used to communicate the
+  // offset to the location of the map check.
+  Register temp = ToRegister(instr->temp());
+  ASSERT(temp.is(r4));
+  __ mov(InstanceofStub::right(), Operand(instr->function()));
+  static const int kAdditionalDelta = 4;
+  int delta = masm_->InstructionsGeneratedSince(map_check) + kAdditionalDelta;
+  Label before_push_delta;
+  __ bind(&before_push_delta);
+  __ BlockConstPoolFor(kAdditionalDelta);
+  __ mov(temp, Operand(delta * kPointerSize));
+  __ StoreToSafepointRegisterSlot(temp);
+  __ Call(stub.GetCode(), RelocInfo::CODE_TARGET);
+  ASSERT_EQ(kAdditionalDelta,
+            masm_->InstructionsGeneratedSince(&before_push_delta));
+  RecordSafepointWithRegisters(
+      instr->pointer_map(), 0, Safepoint::kNoDeoptimizationIndex);
+  // Put the result value into the result register slot and
+  // restore all registers.
+  __ StoreToSafepointRegisterSlot(result);
+
+  __ PopSafepointRegisters();
 }
 
 

src/arm/lithium-codegen-arm.h

@@ -99,6 +99,8 @@ class LCodeGen BASE_EMBEDDED {
   void DoDeferredTaggedToI(LTaggedToI* instr);
   void DoDeferredMathAbsTaggedHeapNumber(LUnaryMathOperation* instr);
   void DoDeferredStackCheck(LGoto* instr);
+  void DoDeferredLInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
+                                        Label* map_check);
 
   // Parallel move support.
   void DoParallelMove(LParallelMove* move);

src/arm/macro-assembler-arm.cc

@@ -485,6 +485,11 @@ void MacroAssembler::PopSafepointRegistersAndDoubles() {
   PopSafepointRegisters();
 }
 
+void MacroAssembler::StoreToSafepointRegisterSlot(Register reg) {
+  str(reg, SafepointRegisterSlot(reg));
+}
+
+
 int MacroAssembler::SafepointRegisterStackIndex(int reg_code) {
   // The registers are pushed starting with the highest encoding,
   // which means that lowest encodings are closest to the stack pointer.
@@ -493,6 +498,11 @@ int MacroAssembler::SafepointRegisterStackIndex(int reg_code) {
 }
 
 
+MemOperand MacroAssembler::SafepointRegisterSlot(Register reg) {
+  return MemOperand(sp, SafepointRegisterStackIndex(reg.code()) * kInstrSize);
+}
+
+
 void MacroAssembler::Ldrd(Register dst1, Register dst2,
                           const MemOperand& src, Condition cond) {
   ASSERT(src.rm().is(no_reg));
@@ -2185,6 +2195,26 @@ void MacroAssembler::CallCFunction(Register function, int num_arguments) {
 }
 
 
+void MacroAssembler::GetRelocatedValueLocation(Register ldr_location,
+                               Register result) {
+  const uint32_t kLdrOffsetMask = (1 << 12) - 1;
+  const int32_t kPCRegOffset = 2 * kPointerSize;
+  ldr(result, MemOperand(ldr_location));
+  if (FLAG_debug_code) {
+    // Check that the instruction is a ldr reg, [pc + offset] .
+    and_(result, result, Operand(kLdrPCPattern));
+    cmp(result, Operand(kLdrPCPattern));
+    Check(eq, "The instruction to patch should be a load from pc.");
+    // 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));
+}
+
+
 #ifdef ENABLE_DEBUGGER_SUPPORT
 CodePatcher::CodePatcher(byte* address, int instructions)
     : address_(address),

src/arm/macro-assembler-arm.h

@@ -234,8 +234,9 @@ class MacroAssembler: public Assembler {
   void PopSafepointRegisters();
   void PushSafepointRegistersAndDoubles();
   void PopSafepointRegistersAndDoubles();
-
+  void StoreToSafepointRegisterSlot(Register reg);
   static int SafepointRegisterStackIndex(int reg_code);
+  static MemOperand SafepointRegisterSlot(Register reg);
 
   // Load two consecutive registers with two consecutive memory locations.
   void Ldrd(Register dst1,
@@ -776,6 +777,15 @@ class MacroAssembler: public Assembler {
                                               Label* failure);
 
 
+  // ---------------------------------------------------------------------------
+  // Patching helpers.
+
+  // Get the location of a relocated constant (its address in the constant pool)
+  // from its load site.
+  void GetRelocatedValueLocation(Register ldr_location,
+                                 Register result);
+
+
  private:
   void Jump(intptr_t target, RelocInfo::Mode rmode, Condition cond = al);
   void Call(intptr_t target, RelocInfo::Mode rmode, Condition cond = al);

src/arm/simulator-arm.cc

@@ -153,7 +153,12 @@ void Debugger::Stop(Instr* instr) {
   if (sim_->isWatchedStop(code) && !sim_->watched_stops[code].desc) {
     sim_->watched_stops[code].desc = msg;
   }
-  PrintF("Simulator hit %s\n", msg);
+  // Print the stop message and code if it is not the default code.
+  if (code != kMaxStopCode) {
+    PrintF("Simulator hit stop %u: %s\n", code, msg);
+  } else {
+    PrintF("Simulator hit %s\n", msg);
+  }
   sim_->set_pc(sim_->get_pc() + 2 * Instr::kInstrSize);
   Debug();
 }