[ExecutionEngine] Avoid repeated hash lookups (NFC) (#130239)

Author: kazutakahirata

llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFAArch64.h

@@ -121,13 +121,13 @@ class RuntimeDyldCOFFAArch64 : public RuntimeDyldCOFF {
     OriginalRelValueRef.Addend = Addend;
     OriginalRelValueRef.SymbolName = TargetName.data();
 
-    auto Stub = Stubs.find(OriginalRelValueRef);
-    if (Stub == Stubs.end()) {
+    auto [Stub, Inserted] = Stubs.try_emplace(OriginalRelValueRef);
+    if (Inserted) {
       LLVM_DEBUG(dbgs() << " Create a new stub function for "
                         << TargetName.data() << "\n");
 
       StubOffset = Section.getStubOffset();
-      Stubs[OriginalRelValueRef] = StubOffset;
+      Stub->second = StubOffset;
       createStubFunction(Section.getAddressWithOffset(StubOffset));
       Section.advanceStubOffset(getMaxStubSize());
     } else {

llvm/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h

@@ -160,13 +160,13 @@ class RuntimeDyldCOFFX86_64 : public RuntimeDyldCOFF {
     OriginalRelValueRef.Addend = Addend;
     OriginalRelValueRef.SymbolName = TargetName.data();
 
-    auto Stub = Stubs.find(OriginalRelValueRef);
-    if (Stub == Stubs.end()) {
+    auto [Stub, Inserted] = Stubs.try_emplace(OriginalRelValueRef);
+    if (Inserted) {
       LLVM_DEBUG(dbgs() << " Create a new stub function for "
                         << TargetName.data() << "\n");
 
       StubOffset = Section.getStubOffset();
-      Stubs[OriginalRelValueRef] = StubOffset;
+      Stub->second = StubOffset;
       createStubFunction(Section.getAddressWithOffset(StubOffset));
       Section.advanceStubOffset(getMaxStubSize());
     } else {