[Lldb-commits] [lldb] [lldb] Delete unreachable code and unncesary string conversions (PR #74119)

[via lldb-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-lldb

Author: Felipe de Azevedo Piovezan (felipepiovezan)

<details>
<summary>Changes</summary>

This PR cleans up OptionArgParser in a couple of ways:

1. We remove unnecessary std::string temporaries
2. Through else-after-return elimination, we prove the existence of unreachable code

---
Full diff: https://github.com/llvm/llvm-project/pull/74119.diff


1 Files Affected:

- (modified) lldb/source/Interpreter/OptionArgParser.cpp (+29-42) 


``````````diff
diff --git a/lldb/source/Interpreter/OptionArgParser.cpp b/lldb/source/Interpreter/OptionArgParser.cpp
index ba2d3416e1838a9..2f2c510462dc79a 100644
--- a/lldb/source/Interpreter/OptionArgParser.cpp
+++ b/lldb/source/Interpreter/OptionArgParser.cpp
@@ -168,7 +168,6 @@ lldb::addr_t OptionArgParser::ToAddress(const ExecutionContext *exe_ctx,
 std::optional<lldb::addr_t>
 OptionArgParser::DoToAddress(const ExecutionContext *exe_ctx, llvm::StringRef s,
                              Status *error_ptr) {
-  bool error_set = false;
   if (s.empty()) {
     if (error_ptr)
       error_ptr->SetErrorStringWithFormat("invalid address expression \"%s\"",
@@ -223,52 +222,40 @@ OptionArgParser::DoToAddress(const ExecutionContext *exe_ctx, llvm::StringRef s,
       if (error_ptr)
         error_ptr->Clear();
       return addr;
-    } else {
-      if (error_ptr) {
-        error_set = true;
-        error_ptr->SetErrorStringWithFormat(
-            "address expression \"%s\" resulted in a value whose type "
-            "can't be converted to an address: %s",
-            s.str().c_str(), valobj_sp->GetTypeName().GetCString());
-      }
     }
+    if (error_ptr)
+      error_ptr->SetErrorStringWithFormat(
+          "address expression \"%s\" resulted in a value whose type "
+          "can't be converted to an address: %s",
+          s.str().c_str(), valobj_sp->GetTypeName().GetCString());
+    return {};
+  }
 
-  } else {
-    // Since the compiler can't handle things like "main + 12" we should try to
-    // do this for now. The compiler doesn't like adding offsets to function
-    // pointer types.
-    static RegularExpression g_symbol_plus_offset_regex(
-        "^(.*)([-\\+])[[:space:]]*(0x[0-9A-Fa-f]+|[0-9]+)[[:space:]]*$");
-
-    llvm::SmallVector<llvm::StringRef, 4> matches;
-    if (g_symbol_plus_offset_regex.Execute(sref, &matches)) {
-      uint64_t offset = 0;
-      std::string name = matches[1].str();
-      std::string sign = matches[2].str();
-      std::string str_offset = matches[3].str();
-      if (!llvm::StringRef(str_offset).getAsInteger(0, offset)) {
-        Status error;
-        addr = ToAddress(exe_ctx, name.c_str(), LLDB_INVALID_ADDRESS, &error);
-        if (addr != LLDB_INVALID_ADDRESS) {
-          if (sign[0] == '+')
-            return addr + offset;
-          else
-            return addr - offset;
-        }
+  // Since the compiler can't handle things like "main + 12" we should try to
+  // do this for now. The compiler doesn't like adding offsets to function
+  // pointer types.
+  static RegularExpression g_symbol_plus_offset_regex(
+      "^(.*)([-\\+])[[:space:]]*(0x[0-9A-Fa-f]+|[0-9]+)[[:space:]]*$");
+
+  llvm::SmallVector<llvm::StringRef, 4> matches;
+  if (g_symbol_plus_offset_regex.Execute(sref, &matches)) {
+    uint64_t offset = 0;
+    llvm::StringRef name = matches[1];
+    llvm::StringRef sign = matches[2];
+    llvm::StringRef str_offset = matches[3];
+    if (!llvm::StringRef(str_offset).getAsInteger(0, offset)) {
+      Status error;
+      addr = ToAddress(exe_ctx, name.c_str(), LLDB_INVALID_ADDRESS, &error);
+      if (addr != LLDB_INVALID_ADDRESS) {
+        if (sign[0] == '+')
+          return addr + offset;
+        return addr - offset;
       }
     }
-
-    if (error_ptr) {
-      error_set = true;
-      error_ptr->SetErrorStringWithFormat(
-          "address expression \"%s\" evaluation failed", s.str().c_str());
-    }
   }
 
-  if (error_ptr) {
-    if (!error_set)
-      error_ptr->SetErrorStringWithFormat("invalid address expression \"%s\"",
-                                          s.str().c_str());
-  }
+  if (error_ptr)
+    error_ptr->SetErrorStringWithFormat(
+        "address expression \"%s\" evaluation failed", s.str().c_str());
   return {};
 }

``````````

</details>


https://github.com/llvm/llvm-project/pull/74119