[llvm] [InstCombine] Handle more even/odd math functions (PR #81324)

[Artem Tyurin via llvm-commits]

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@@ -2797,6 +2797,21 @@ static bool insertSinCosCall(IRBuilderBase &B, Function *OrigCallee, Value *Arg,
   return true;
 }
 
+Value *LibCallSimplifier::optimizeSymmetric(CallInst *CI, bool IsEven,
+                                            IRBuilderBase &B) {
+  Value *X;
+  if (match(CI->getArgOperand(0), m_OneUse(m_FNeg(m_Value(X))))) {
+    auto *CallInst = copyFlags(*CI, B.CreateCall(CI->getCalledFunction(), {X}));
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agentcooper wrote:

Done. I've added FMF flags (`reassoc`) and general flags (`tail`) to the call site in the original test.

https://github.com/llvm/llvm-project/pull/81324