[llvm] [DWARF] Avoid repeated hash lookups (NFC) (PR #125633)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/125633

None

>From 1e2526f14a0d43bde57be502cd62ba9d3f454b7d Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Mon, 3 Feb 2025 16:38:05 -0800
Subject: [PATCH] [DWARF] Avoid repeated hash lookups (NFC)

---
 llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
index 8bf513538de7c7e..107e79cc5a05ae4 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFVerifier.cpp
@@ -967,21 +967,20 @@ void DWARFVerifier::verifyDebugLineStmtOffsets() {
       // here because we validate this in the .debug_info verifier.
       continue;
     }
-    auto Iter = StmtListToDie.find(LineTableOffset);
-    if (Iter != StmtListToDie.end()) {
+    auto [Iter, Inserted] = StmtListToDie.try_emplace(LineTableOffset, Die);
+    if (!Inserted) {
       ++NumDebugLineErrors;
+      const auto &OldDie = Iter->second;
       ErrorCategory.Report("Identical DW_AT_stmt_list section offset", [&]() {
         error() << "two compile unit DIEs, "
-                << format("0x%08" PRIx64, Iter->second.getOffset()) << " and "
+                << format("0x%08" PRIx64, OldDie.getOffset()) << " and "
                 << format("0x%08" PRIx64, Die.getOffset())
                 << ", have the same DW_AT_stmt_list section offset:\n";
-        dump(Iter->second);
+        dump(OldDie);
         dump(Die) << '\n';
       });
       // Already verified this line table before, no need to do it again.
-      continue;
     }
-    StmtListToDie[LineTableOffset] = Die;
   }
 }