[llvm] [llvm-profgen] Avoid repeated hash lookups (NFC) (PR #126467)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-pgo

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/126467.diff


1 Files Affected:

- (modified) llvm/tools/llvm-profgen/MissingFrameInferrer.cpp (+3-2) 


``````````diff
diff --git a/llvm/tools/llvm-profgen/MissingFrameInferrer.cpp b/llvm/tools/llvm-profgen/MissingFrameInferrer.cpp
index ee49950f39ca4e2..eefe38cd3fa0025 100644
--- a/llvm/tools/llvm-profgen/MissingFrameInferrer.cpp
+++ b/llvm/tools/llvm-profgen/MissingFrameInferrer.cpp
@@ -206,11 +206,12 @@ uint64_t MissingFrameInferrer::computeUniqueTailCallPath(
 
 uint64_t MissingFrameInferrer::computeUniqueTailCallPath(
     uint64_t From, BinaryFunction *To, SmallVectorImpl<uint64_t> &Path) {
-  if (!TailCallEdgesF.count(From))
+  auto It = TailCallEdgesF.find(From);
+  if (It == TailCallEdgesF.end())
     return 0;
   Path.push_back(From);
   uint64_t NumPaths = 0;
-  for (auto Target : TailCallEdgesF[From]) {
+  for (auto Target : It->second) {
     NumPaths += computeUniqueTailCallPath(Target, To, Path);
     // Stop analyzing the remaining if we are already seeing more than one
     // reachable paths.

``````````

</details>


https://github.com/llvm/llvm-project/pull/126467