Refactor SimplifyFunctionName to flatten nested function calls.

src/proto.cc

@@ -189,8 +189,8 @@ uint64_t ProfileProtoBuilder::LocationID(const string &class_name,
     frame_name += signature;
   }
 
-  const string simplified_name =
-      ::google::javaprofiler::SimplifyFunctionName(frame_name);
+  string simplified_name = frame_name;
+  ::google::javaprofiler::SimplifyFunctionName(&simplified_name);
 
   uint64_t function_id = builder_.FunctionId(
       simplified_name.c_str(), frame_name.c_str(), file_name.c_str(), 0);

third_party/javaprofiler/profile_proto_builder.cc

@@ -316,7 +316,8 @@ perftools::profiles::Location *LocationBuilder::LocationFor(
 
   auto line = location->add_line();
 
-  auto simplified_name = SimplifyFunctionName(function_name);
+  string simplified_name = function_name;
+  SimplifyFunctionName(&simplified_name);
   auto function_id = builder_->FunctionId(
       simplified_name.c_str(), function_name.c_str(), file_name.c_str(), 0);
 

third_party/javaprofiler/stacktrace_fixer.cc

@@ -27,94 +27,101 @@ namespace {
 // followed by specified suffix chars and removing those. For example,
 // calling the function with ("foo123bar", "foo", "321") returns "foobar".
 template <size_t M, size_t N>
-string SimplifySuffixedName(string name, const char (&trigger)[M],
-                            const char (&suffix_chars)[N]) {
+void SimplifySuffixedName(string *name, const char (&trigger)[M],
+                          const char (&suffix_chars)[N]) {
   size_t first = 0;
-  while ((first = name.find(trigger, first)) != std::string::npos) {
+  while ((first = name->find(trigger, first)) != std::string::npos) {
     first += M - 1;  // Exclude last zero char.
-    size_t last = name.find_first_not_of(suffix_chars, first, N);
+    size_t last = name->find_first_not_of(suffix_chars, first, N);
     if (last == std::string::npos) {
-      name.erase(first);
+      name->erase(first);
       break;
     }
-    name.erase(first, last - first);
+    name->erase(first, last - first);
   }
-  return name;
 }
 
 // Simplifies the name of a method in a dynamic class (with '$$FastClassBy*$$'
 // or '$$EnhancedBy*$$' in its name) to make it more human readable, and group
 // related functions under a single name. This could be done with a regexp
 // replacement, but including RE2 increases the size of the agent.
-string SimplifyDynamicClassName(string name) {
+void SimplifyDynamicClassName(string *name) {
   // Replace $$[0-9a-f]+ by $$ to remove unique values, for example in
   // $FastClassByCGLIB$$fd6bdf6d.invoke.
-  return SimplifySuffixedName(std::move(name), "$$", "0123456789abcdef");
+  SimplifySuffixedName(name, "$$", "0123456789abcdef");
 }
 
 // Simplifies the name of a lambda method to replace $$Lambda$[0-9]+\.[0-9]+ by
 // $$Lambda$ to remove unique values, for example in
 // com.google.something.Something$$Lambda$197.1849072452.run.
-string SimplifyLambdaName(string name) {
+void SimplifyLambdaName(string *name) {
   constexpr char trigger[] = "$$Lambda$";
   constexpr char digits[] = "0123456789";
   const size_t trigger_length = strlen(trigger);
 
   // Assume and handle just one instance of a $$Lambda$ pattern.
-  size_t first = name.find(trigger);
+  size_t first = name->find(trigger);
   if (first == std::string::npos) {
-    return name;
+    return;
   }
   first += trigger_length;
-  if (first >= name.size() || !isdigit(name[first])) {
-    return name;
+  if (first >= name->size() || !isdigit((*name)[first])) {
+    return;
   }
-  size_t last = name.find_first_not_of(digits, first);
-  if (last == std::string::npos || name[last] != '.') {
-    return name;
+  size_t last = name->find_first_not_of(digits, first);
+  if (last == std::string::npos || (*name)[last] != '.') {
+    return;
   }
   last++;  // skip the dot
-  if (last >= name.size() || !isdigit(name[last])) {
-    return name;
+  if (last >= name->size() || !isdigit((*name)[last])) {
+    return;
   }
-  last = name.find_first_not_of(digits, last);
+  last = name->find_first_not_of(digits, last);
   if (last == std::string::npos) {
-    name.erase(first);
-    return name;
+    name->erase(first);
+    return;
   }
-  name.erase(first, last - first);
-  return name;
+  name->erase(first, last - first);
 }
 
 constexpr char digits[] = "0123456789";
 
 // Simplifies the name of a method generated by the runtime as a reflection
 // stub. See the test file for examples, or generateName() in
 // jdk/internal/reflect/MethodAccessorGenerator.java.
-string SimplifyInternalReflectionMethodName(string name) {
-  return SimplifySuffixedName(
-      SimplifySuffixedName(
-          SimplifySuffixedName(
-              std::move(name),
-              "jdk.internal.reflect.GeneratedConstructorAccessor",
-              digits),
-          "jdk.internal.reflect.GeneratedMethodAccessor",
-          digits),
+void SimplifyInternalReflectionMethodName(string *name) {
+  SimplifySuffixedName(
+      name,
+      "jdk.internal.reflect.GeneratedConstructorAccessor",
+      digits);
+
+  SimplifySuffixedName(
+      name,
+      "jdk.internal.reflect.GeneratedMethodAccessor",
+      digits);
+
+  SimplifySuffixedName(
+      name,
       "jdk.internal.reflect.GeneratedSerializationConstructorAccessor",
       digits);
 }
 
 // Simplifies the name of a method generated by the runtime as a reflection
 // stub. See the test file for examples, or generateName() in
 // sun/reflect/MethodAccessorGenerator.java.
-string SimplifyReflectionMethodName(string name) {
-  return SimplifySuffixedName(
-      SimplifySuffixedName(
-          SimplifySuffixedName(std::move(name),
-                               "sun.reflect.GeneratedConstructorAccessor",
-                               digits),
-          "sun.reflect.GeneratedMethodAccessor",
-          digits),
+void SimplifyReflectionMethodName(string *name) {
+  SimplifySuffixedName(
+      name,
+      "sun.reflect.GeneratedConstructorAccessor",
+      digits);
+
+  SimplifySuffixedName(
+      name,
+      "sun.reflect.GeneratedMethodAccessor",
+      digits);
+
+  SimplifySuffixedName(
+      name,
       "sun.reflect.GeneratedSerializationConstructorAccessor",
       digits);
 }
@@ -247,12 +254,11 @@ string ParseMethodTypeSignatureWithReturn(const char *buffer, int buffer_size,
 
 }  // namespace
 
-string SimplifyFunctionName(const string& name) {
-  // The calls should be kept nested, without explicit string declarations, so
-  // that move semantics can be applied to minimize copies.
-  return SimplifyInternalReflectionMethodName(
-      SimplifyReflectionMethodName(
-          SimplifyLambdaName(SimplifyDynamicClassName(name))));
+void SimplifyFunctionName(string* name) {
+  SimplifyDynamicClassName(name);
+  SimplifyLambdaName(name);
+  SimplifyReflectionMethodName(name);
+  SimplifyInternalReflectionMethodName(name);
 }
 
 void FixPath(string *s) {

third_party/javaprofiler/stacktrace_fixer.h

@@ -26,7 +26,7 @@ namespace google {
 namespace javaprofiler {
   // Simplifies the name of a function to make it more human readable, and group
   // related functions under a single name.
-  string SimplifyFunctionName(const string& name);
+  void SimplifyFunctionName(string *name);
 
   // Fix the parameter signature from a JVM type signature to a pretty-print
   // one.