[llvm] [IPO] Avoid repeated hash lookups (NFC) (PR #131720)

[Shilei Tian via llvm-commits]

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@@ -266,7 +266,7 @@ doPromotion(Function *F, FunctionAnalysisManager &FAM,
           ArgAttrVec.push_back(AttributeSet());
         }
       } else {
-        assert(ArgsToPromote.count(&*I) && I->use_empty());
+        assert(ArgIt != ArgsToPromote.end() && I->use_empty());
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shiltian wrote:

The first half of the assertion is actually not needed because if it can reach here, it means the first two conditions must fail.

https://github.com/llvm/llvm-project/pull/131720