[llvm] [NVPTX] Avoid repeated map lookups (NFC) (PR #127169)

[Kazu Hirata via llvm-commits]

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@@ -128,13 +128,16 @@ static std::optional<unsigned> findOneNVVMAnnotation(const GlobalValue *gv,
   auto &AC = getAnnotationCache();
   std::lock_guard<sys::Mutex> Guard(AC.Lock);
   const Module *m = gv->getParent();
-  if (AC.Cache.find(m) == AC.Cache.end())
+  auto ACIt = AC.Cache.find(m);
+  if (ACIt == AC.Cache.end())
     cacheAnnotationFromMD(m, gv);
-  else if (AC.Cache[m].find(gv) == AC.Cache[m].end())
+  else if (ACIt->second.find(gv) == ACIt->second.end())
     cacheAnnotationFromMD(m, gv);
-  if (AC.Cache[m][gv].find(prop) == AC.Cache[m][gv].end())
+  auto &KVP = AC.Cache[m][gv];
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kazutakahirata wrote:

Revised.  Thanks!

https://github.com/llvm/llvm-project/pull/127169