[lldb] Simplify string comparisons (NFC) (llvm#139394)

Author: kazutakahirata

lldb/source/Plugins/Disassembler/LLVMC/DisassemblerLLVMC.cpp

@@ -818,7 +818,7 @@ class InstructionLLVMC : public lldb_private::Instruction {
             return std::make_pair(ret, osi);
           }
         case 'x':
-          if (!str.compare("0")) {
+          if (str == "0") {
             is_hex = true;
             str.push_back(*osi);
           } else {

lldb/source/Plugins/ExpressionParser/Clang/ASTResultSynthesizer.cpp

@@ -83,14 +83,14 @@ void ASTResultSynthesizer::TransformTopLevelDecl(Decl *D) {
   } else if (!m_top_level) {
     if (ObjCMethodDecl *method_decl = dyn_cast<ObjCMethodDecl>(D)) {
       if (m_ast_context &&
-          !method_decl->getSelector().getAsString().compare("$__lldb_expr:")) {
+          method_decl->getSelector().getAsString() == "$__lldb_expr:") {
         RecordPersistentTypes(method_decl);
         SynthesizeObjCMethodResult(method_decl);
       }
     } else if (FunctionDecl *function_decl = dyn_cast<FunctionDecl>(D)) {
       // When completing user input the body of the function may be a nullptr.
       if (m_ast_context && function_decl->hasBody() &&
-          !function_decl->getNameInfo().getAsString().compare("$__lldb_expr")) {
+          function_decl->getNameInfo().getAsString() == "$__lldb_expr") {
         RecordPersistentTypes(function_decl);
         SynthesizeFunctionResult(function_decl);
       }

lldb/source/Plugins/Process/elf-core/ThreadElfCore.cpp

@@ -278,9 +278,9 @@ size_t ELFLinuxPrStatus::GetSize(const lldb_private::ArchSpec &arch) {
   if (arch.IsMIPS()) {
     std::string abi = arch.GetTargetABI();
     assert(!abi.empty() && "ABI is not set");
-    if (!abi.compare("n64"))
+    if (abi == "n64")
       return sizeof(ELFLinuxPrStatus);
-    else if (!abi.compare("o32"))
+    else if (abi == "o32")
       return mips_linux_pr_status_size_o32;
     // N32 ABI
     return mips_linux_pr_status_size_n32;