[turbofan] Explicitly mark call sites as patchable.

src/compiler/linkage.h

 // Copyright 2014 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.
 
 #ifndef V8_COMPILER_LINKAGE_H_
 #define V8_COMPILER_LINKAGE_H_
 
-#include "src/v8.h"
-
+#include "src/base/flags.h"
 #include "src/code-stubs.h"
 #include "src/compiler/frame.h"
 #include "src/compiler/machine-operator.h"
 #include "src/compiler/node.h"
 #include "src/compiler/operator.h"
 #include "src/zone.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
@@ skipping 10 matching lines @@
   static const int16_t ANY_REGISTER = 32767;
 
  private:
   friend class CallDescriptor;
   friend class OperandGenerator;
   MachineType rep_;
   int16_t location_;  // >= 0 implies register, otherwise stack slot.
 };
 
 
-class CallDescriptor : public ZoneObject {
+class CallDescriptor V8_FINAL : public ZoneObject {
  public:
   // Describes whether the first parameter is a code object, a JSFunction,
   // or an address--all of which require different machine sequences to call.
   enum Kind { kCallCodeObject, kCallJSFunction, kCallAddress };
 
-  // TODO(jarin) kLazyDeoptimization and kNeedsFrameState should be unified.

[Michael Starzinger, 2014/08/27 12:50:11]

nit: I think the TODO for Jaro still applies, better double-check with him
before removing it.

[Benedikt Meurer, 2014/08/28 11:46:57]

Ups, didn't mean to remove that.

-  enum DeoptimizationSupport {
-    kNoDeoptimization = 0,
-    kLazyDeoptimization = 1,
-    kNeedsFrameState = 2
+  enum Flag {
+    kNoFlags = 0u,
+    kLazyDeoptimization = 1u << 0,
+    kNeedsFrameState = 1u << 1,
+    kPatchableCallSite = 1u << 2,
+    kNeedsNopAfterCall = 1u << 3,
+    kPatchableCallSiteWithNop = kPatchableCallSite | kNeedsNopAfterCall
   };
+  DEFINE_FLAGS(Flags, Flag);
 
   CallDescriptor(Kind kind, int8_t return_count, int16_t parameter_count,
                  int16_t input_count, LinkageLocation* locations,
                  Operator::Property properties, RegList callee_saved_registers,
-                 DeoptimizationSupport deoptimization_support,
-                 const char* debug_name = "")
+                 Flags flags, const char* debug_name = "")
       : kind_(kind),
         return_count_(return_count),
         parameter_count_(parameter_count),
         input_count_(input_count),
         locations_(locations),
         properties_(properties),
         callee_saved_registers_(callee_saved_registers),
-        deoptimization_support_(deoptimization_support),
+        flags_(flags),
         debug_name_(debug_name) {}
   // Returns the kind of this call.
   Kind kind() const { return kind_; }
 
   // Returns {true} if this descriptor is a call to a JSFunction.
   bool IsJSFunctionCall() const { return kind_ == kCallJSFunction; }
 
   // The number of return values from this call, usually 0 or 1.
   int ReturnCount() const { return return_count_; }
 
   // The number of JavaScript parameters to this call, including receiver,
   // but not the context.
   int ParameterCount() const { return parameter_count_; }
 
   int InputCount() const { return input_count_; }
 
   int FrameStateCount() const { return NeedsFrameState() ? 1 : 0; }
 
-  bool CanLazilyDeoptimize() const {
-    return (deoptimization_support() & kLazyDeoptimization) != 0;
-  }
+  Flags flags() const { return flags_; }
 
-  bool NeedsFrameState() const {
-    return (deoptimization_support() & kNeedsFrameState) != 0;
-  }
-
-  DeoptimizationSupport deoptimization_support() const {
-    return deoptimization_support_;
-  }
+  bool CanLazilyDeoptimize() const { return flags() & kLazyDeoptimization; }
+  bool NeedsFrameState() const { return flags() & kNeedsFrameState; }
 
   LinkageLocation GetReturnLocation(int index) {
     DCHECK(index < return_count_);
     return locations_[0 + index];  // return locations start at 0.
   }
 
   LinkageLocation GetInputLocation(int index) {
     DCHECK(index < input_count_ + 1);  // input_count + 1 is the context.
     return locations_[return_count_ + index];  // inputs start after returns.
   }
 
   // Operator properties describe how this call can be optimized, if at all.
   Operator::Property properties() const { return properties_; }
 
   // Get the callee-saved registers, if any, across this call.
   RegList CalleeSavedRegisters() { return callee_saved_registers_; }
 
   const char* debug_name() const { return debug_name_; }
 
  private:
   friend class Linkage;
 
   Kind kind_;
   int8_t return_count_;
   int16_t parameter_count_;
   int16_t input_count_;
   LinkageLocation* locations_;
   Operator::Property properties_;
   RegList callee_saved_registers_;
-  DeoptimizationSupport deoptimization_support_;
+  Flags flags_;
   const char* debug_name_;
 };
 
+DEFINE_OPERATORS_FOR_FLAGS(CallDescriptor::Flags)
+
 OStream& operator<<(OStream& os, const CallDescriptor& d);
 OStream& operator<<(OStream& os, const CallDescriptor::Kind& k);
 
 // Defines the linkage for a compilation, including the calling conventions
 // for incoming parameters and return value(s) as well as the outgoing calling
 // convention for any kind of call. Linkage is generally architecture-specific.
 //
 // Can be used to translate {arg_index} (i.e. index of the call node input) as
 // well as {param_index} (i.e. as stored in parameter nodes) into an operator
 // representing the architecture-specific location. The following call node
@@ skipping 10 matching lines @@
       : info_(info), incoming_(incoming) {}
 
   // The call descriptor for this compilation unit describes the locations
   // of incoming parameters and the outgoing return value(s).
   CallDescriptor* GetIncomingDescriptor() { return incoming_; }
   CallDescriptor* GetJSCallDescriptor(int parameter_count);
   static CallDescriptor* GetJSCallDescriptor(int parameter_count, Zone* zone);
   CallDescriptor* GetRuntimeCallDescriptor(
       Runtime::FunctionId function, int parameter_count,
       Operator::Property properties,
-      CallDescriptor::DeoptimizationSupport can_deoptimize =
-          CallDescriptor::kNoDeoptimization);
-  static CallDescriptor* GetRuntimeCallDescriptor(
-      Runtime::FunctionId function, int parameter_count,
-      Operator::Property properties,
-      CallDescriptor::DeoptimizationSupport can_deoptimize, Zone* zone);
+      CallDescriptor::Flags flags = CallDescriptor::kNoFlags);
+  static CallDescriptor* GetRuntimeCallDescriptor(Runtime::FunctionId function,
+                                                  int parameter_count,
+                                                  Operator::Property properties,
+                                                  CallDescriptor::Flags flags,
+                                                  Zone* zone);
 
   CallDescriptor* GetStubCallDescriptor(
       CodeStubInterfaceDescriptor* descriptor, int stack_parameter_count = 0,
-      CallDescriptor::DeoptimizationSupport can_deoptimize =
-          CallDescriptor::kNoDeoptimization);
+      CallDescriptor::Flags flags = CallDescriptor::kNoFlags);
   static CallDescriptor* GetStubCallDescriptor(
       CodeStubInterfaceDescriptor* descriptor, int stack_parameter_count,
-      CallDescriptor::DeoptimizationSupport can_deoptimize, Zone* zone);
+      CallDescriptor::Flags flags, Zone* zone);
 
   // Creates a call descriptor for simplified C calls that is appropriate
   // for the host platform. This simplified calling convention only supports
   // integers and pointers of one word size each, i.e. no floating point,
   // structs, pointers to members, etc.
   static CallDescriptor* GetSimplifiedCDescriptor(
       Zone* zone, int num_params, MachineType return_type,
       const MachineType* param_types);
 
   // Get the location of an (incoming) parameter to this function.
@@ skipping 12 matching lines @@
   // caller's frame. The {extra} parameter indicates an additional offset from
   // the frame offset, e.g. to index into part of a double slot.
   FrameOffset GetFrameOffset(int spill_slot, Frame* frame, int extra = 0);
 
   CompilationInfo* info() const { return info_; }
 
  private:
   CompilationInfo* info_;
   CallDescriptor* incoming_;
 };
-}
-}
-}  // namespace v8::internal::compiler
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_COMPILER_LINKAGE_H_