[turbofan] Introduce dedicated CallFrequency class.

src/compiler/bytecode-graph-builder.h

Index: src/compiler/bytecode-graph-builder.h
diff --git a/src/compiler/bytecode-graph-builder.h b/src/compiler/bytecode-graph-builder.h
index d09932701103ba255dab466b3021fe81620bc135..6b583355081bbe4030a1c538e097052ef439841a 100644
--- a/src/compiler/bytecode-graph-builder.h
+++ b/src/compiler/bytecode-graph-builder.h
@@ -29,7 +29,7 @@ class BytecodeGraphBuilder {
   BytecodeGraphBuilder(
       Zone* local_zone, Handle<SharedFunctionInfo> shared,
       Handle<FeedbackVector> feedback_vector, BailoutId osr_ast_id,
-      JSGraph* jsgraph, float invocation_frequency,
+      JSGraph* jsgraph, CallFrequency invocation_frequency,
       SourcePositionTable* source_positions,
       int inlining_id = SourcePosition::kNotInlined,
       JSTypeHintLowering::Flags flags = JSTypeHintLowering::kNoFlags);
@@ -206,7 +206,7 @@ class BytecodeGraphBuilder {
 
   // Helper function to compute call frequency from the recorded type
   // feedback.
-  float ComputeCallFrequency(int slot_id) const;
+  CallFrequency ComputeCallFrequency(int slot_id) const;
 
   // Control flow plumbing.
   void BuildJump();
@@ -315,7 +315,7 @@ class BytecodeGraphBuilder {
 
   Zone* local_zone_;
   JSGraph* jsgraph_;
-  float const invocation_frequency_;
+  CallFrequency const invocation_frequency_;
   Handle<BytecodeArray> bytecode_array_;
   Handle<HandlerTable> exception_handler_table_;
   Handle<FeedbackVector> feedback_vector_;