Store the length of the strings to avoid call to strlen().

Author: redstar

llvm/include/llvm/Analysis/TargetLibraryInfo.h

@@ -174,7 +174,8 @@ class TargetLibraryInfoImpl {
   /// Forces a function to be marked as available and provide an alternate name
   /// that must be used.
   void setAvailableWithName(LibFunc F, StringRef Name) {
-    if (StandardNamesStrTable.getCString(StandardNamesOffsets[F]) != Name) {
+    if (StringRef(StandardNamesStrTable.getCString(StandardNamesOffsets[F]),
+                  StandardNamesSizeTable[F]) != Name) {
       setState(F, CustomName);
       CustomNames[F] = std::string(Name);
       assert(CustomNames.contains(F));
@@ -452,17 +453,18 @@ class TargetLibraryInfo {
   /// Return the canonical name for a LibFunc. This should not be used for
   /// semantic purposes, use getName instead.
   static StringRef getStandardName(LibFunc F) {
-    return TargetLibraryInfoImpl::StandardNamesStrTable.getCString(
-        TargetLibraryInfoImpl::StandardNamesOffsets[F]);
+    return StringRef(TargetLibraryInfoImpl::StandardNamesStrTable.getCString(
+                         TargetLibraryInfoImpl::StandardNamesOffsets[F]),
+                     TargetLibraryInfoImpl::StandardNamesSizeTable[F]);
   }
 
   StringRef getName(LibFunc F) const {
     auto State = getState(F);
     if (State == TargetLibraryInfoImpl::Unavailable)
       return StringRef();
     if (State == TargetLibraryInfoImpl::StandardName)
-      return Impl->StandardNamesStrTable.getCString(
-          Impl->StandardNamesOffsets[F]);
+      return StringRef(Impl->StandardNamesStrTable.getCString(
+          Impl->StandardNamesOffsets[F]), Impl->StandardNamesSizeTable[F]);
     assert(State == TargetLibraryInfoImpl::CustomName);
     return Impl->CustomNames.find(F)->second;
   }

llvm/test/TableGen/TargetLibraryInfo.td

@@ -52,12 +52,19 @@ def printf : TargetLibCall< "printf", [Int, Ptr, Ellip]>;
 // CHECK-NEXT:   11, // fmaxf
 // CHECK-NEXT:   17, // printf
 // CHECK-NEXT: };
+// CHECK-NEXT: const uint8_t TargetLibraryInfoImpl::StandardNamesSizeTable[] = {  0,
+// CHECK-NEXT:   4,
+// CHECK-NEXT:   4,
+// CHECK-NEXT:   5,
+// CHECK-NEXT:   6,
+// CHECK-NEXT: };
 // CHECK-NEXT: #endif
 
 // CHECK:      #ifdef GET_TARGET_LIBRARY_INFO_IMPL_DECL
 // CHECK-NEXT: #undef GET_TARGET_LIBRARY_INFO_IMPL_DECL
 // CHECK-NEXT: LLVM_ABI static const llvm::StringTable StandardNamesStrTable;
 // CHECK-NEXT: LLVM_ABI static const llvm::StringTable::Offset StandardNamesOffsets[5];
+// CHECK-NEXT: LLVM_ABI static const uint8_t StandardNamesSizeTable[5];
 // CHECK-NEXT: #endif
 
 // CHECK:      #ifdef GET_TARGET_LIBRARY_INFO_SIGNATURE_TABLE
@@ -91,7 +98,7 @@ def printf : TargetLibCall< "printf", [Int, Ptr, Ellip]>;
 // CHECK-NEXT:   /* 7 */ Floating, Same, Same, NoFuncArgType,
 // CHECK-NEXT:   /* 11 */ Void, NoFuncArgType,
 // CHECK-NEXT: };
-// CHECK-NEXT: static const unsigned short SignatureOffset[] = {
+// CHECK-NEXT: static const uint16_t SignatureOffset[] = {
 // CHECK-NEXT:   11, //
 // CHECK-NEXT:   4, // cosf
 // CHECK-NEXT:   4, // sinf

llvm/utils/TableGen/Basic/TargetLibraryInfoEmitter.cpp

@@ -97,12 +97,19 @@ void TargetLibraryInfoEmitter::emitTargetLibraryInfoStringTable(
     OS.indent(2) << Table.GetStringOffset(Str) << ", // " << Str << "\n";
   }
   OS << "};\n";
+  OS << "const uint8_t TargetLibraryInfoImpl::StandardNamesSizeTable[] = {";
+  OS << "  0,\n";
+  for (const auto *R : AllTargetLibcalls)
+    OS.indent(2) << R->getValueAsString("String").size() << ",\n";
+  OS << "};\n";
   OS << "#endif\n\n";
   OS << "#ifdef GET_TARGET_LIBRARY_INFO_IMPL_DECL\n";
   OS << "#undef GET_TARGET_LIBRARY_INFO_IMPL_DECL\n";
   OS << "LLVM_ABI static const llvm::StringTable StandardNamesStrTable;\n";
   OS << "LLVM_ABI static const llvm::StringTable::Offset StandardNamesOffsets["
      << NumEl << "];\n";
+  OS << "LLVM_ABI static const uint8_t StandardNamesSizeTable[" << NumEl
+     << "];\n";
   OS << "#endif\n\n";
 }
 
@@ -144,7 +151,7 @@ void TargetLibraryInfoEmitter::emitTargetLibraryInfoSignatureTable(
   OS << "static const FuncArgTypeID SignatureTable[] = {\n";
   SignatureTable.emit(OS, [](raw_ostream &OS, StringRef E) { OS << E; });
   OS << "};\n";
-  OS << "static const unsigned short SignatureOffset[] = {\n";
+  OS << "static const uint16_t SignatureOffset[] = {\n";
   OS.indent(2) << SignatureTable.get(NoFuncSig) << ", //\n";
   for (const auto *R : AllTargetLibcalls) {
     OS.indent(2) << SignatureTable.get(GetSignature(R)) << ", // "