AIX: Changing how CallFrequency object being passed from 'by value' to 'by...

AIX: Changing how CallFrequency object being passed from 'by value' to 'by constant reference' to avoid copy error.

GCC compile issue in AIX: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61976

There is a gcc compile issue in AIX: Being passed by values may occur a
copy error, which can be avoided by being passed by reference. This is
why the old way of CallFrequency object 'being passed by values’ has
been changed to the new way of CallFrequency object 'being passed by
references' to avoid this issue.

Bug: v8:8193
Change-Id: I3f2e662a9ef5b641b6e978c3e91167bacc0d13d2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1689027Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#62788}

src/compiler/js-operator.cc

@@ -17,7 +17,7 @@ namespace v8 {
 namespace internal {
 namespace compiler {
 
-std::ostream& operator<<(std::ostream& os, CallFrequency f) {
+std::ostream& operator<<(std::ostream& os, CallFrequency const& f) {
   if (f.IsUnknown()) return os << "unknown";
   return os << f.value();
 }
@@ -28,7 +28,6 @@ CallFrequency CallFrequencyOf(Operator const* op) {
   return OpParameter<CallFrequency>(op);
 }
 
-
 std::ostream& operator<<(std::ostream& os,
                          ConstructForwardVarargsParameters const& p) {
   return os << p.arity() << ", " << p.start_index();
@@ -843,7 +842,8 @@ const Operator* JSOperatorBuilder::Call(size_t arity,
       parameters);                                 // parameter
 }
 
-const Operator* JSOperatorBuilder::CallWithArrayLike(CallFrequency frequency) {
+const Operator* JSOperatorBuilder::CallWithArrayLike(
+    CallFrequency const& frequency) {
   return new (zone()) Operator1<CallFrequency>(                 // --
       IrOpcode::kJSCallWithArrayLike, Operator::kNoProperties,  // opcode
       "JSCallWithArrayLike",                                    // name
@@ -913,7 +913,7 @@ const Operator* JSOperatorBuilder::Construct(uint32_t arity,
 }
 
 const Operator* JSOperatorBuilder::ConstructWithArrayLike(
-    CallFrequency frequency) {
+    CallFrequency const& frequency) {
   return new (zone()) Operator1<CallFrequency>(  // --
       IrOpcode::kJSConstructWithArrayLike,       // opcode
       Operator::kNoProperties,                   // properties

src/compiler/js-operator.h

@@ -48,7 +48,7 @@ class CallFrequency final {
   }
   bool operator!=(CallFrequency const& that) const { return !(*this == that); }
 
-  friend size_t hash_value(CallFrequency f) {
+  friend size_t hash_value(CallFrequency const& f) {
     return bit_cast<uint32_t>(f.value_);
   }
 
@@ -58,7 +58,7 @@ class CallFrequency final {
   float value_;
 };
 
-std::ostream& operator<<(std::ostream&, CallFrequency);
+std::ostream& operator<<(std::ostream&, CallFrequency const&);
 
 CallFrequency CallFrequencyOf(Operator const* op) V8_WARN_UNUSED_RESULT;
 
@@ -101,7 +101,7 @@ ConstructForwardVarargsParameters const& ConstructForwardVarargsParametersOf(
 // used as a parameter by JSConstruct and JSConstructWithSpread operators.
 class ConstructParameters final {
  public:
-  ConstructParameters(uint32_t arity, CallFrequency frequency,
+  ConstructParameters(uint32_t arity, CallFrequency const& frequency,
                       VectorSlotPair const& feedback)
       : arity_(arity), frequency_(frequency), feedback_(feedback) {}
 
@@ -757,7 +757,7 @@ class V8_EXPORT_PRIVATE JSOperatorBuilder final
       VectorSlotPair const& feedback = VectorSlotPair(),
       ConvertReceiverMode convert_mode = ConvertReceiverMode::kAny,
       SpeculationMode speculation_mode = SpeculationMode::kDisallowSpeculation);
-  const Operator* CallWithArrayLike(CallFrequency frequency);
+  const Operator* CallWithArrayLike(CallFrequency const& frequency);
   const Operator* CallWithSpread(
       uint32_t arity, CallFrequency const& frequency = CallFrequency(),
       VectorSlotPair const& feedback = VectorSlotPair(),
@@ -770,7 +770,7 @@ class V8_EXPORT_PRIVATE JSOperatorBuilder final
   const Operator* Construct(uint32_t arity,
                             CallFrequency const& frequency = CallFrequency(),
                             VectorSlotPair const& feedback = VectorSlotPair());
-  const Operator* ConstructWithArrayLike(CallFrequency frequency);
+  const Operator* ConstructWithArrayLike(CallFrequency const& frequency);
   const Operator* ConstructWithSpread(
       uint32_t arity, CallFrequency const& frequency = CallFrequency(),
       VectorSlotPair const& feedback = VectorSlotPair());