[memprof] Avoid repeated hash lookups (NFC) (#136268)
Note that we don't have to worry about CallstackProfileData[Id]
default-constructing the value side of a new map entry. If that
happens, AccessHistogramSize > 0 wouldn't be true, and the new map
entry gets deleted right away.
diff --git a/llvm/lib/ProfileData/MemProfReader.cpp b/llvm/lib/ProfileData/MemProfReader.cpp
index c57f9b2..e0f280b 100644
--- a/llvm/lib/ProfileData/MemProfReader.cpp
+++ b/llvm/lib/ProfileData/MemProfReader.cpp
@@ -600,9 +600,12 @@
// Drop the entries where the callstack is empty.
for (const uint64_t Id : EntriesToErase) {
StackMap.erase(Id);
- if (CallstackProfileData[Id].AccessHistogramSize > 0)
- free((void *)CallstackProfileData[Id].AccessHistogram);
- CallstackProfileData.erase(Id);
+ if (auto It = CallstackProfileData.find(Id);
+ It != CallstackProfileData.end()) {
+ if (It->second.AccessHistogramSize > 0)
+ free((void *)It->second.AccessHistogram);
+ CallstackProfileData.erase(It);
+ }
}
if (StackMap.empty())
