[llvm] SimplifyLibCalls: Prefer to emit intrinsic in pow(2, x) -> ldexp(1, x) (PR #92363)

[Matt Arsenault via llvm-commits]

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@@ -2092,11 +2092,19 @@ Value *LibCallSimplifier::replacePowWithExp(CallInst *Pow, IRBuilderBase &B) {
   if (!Ty->isVectorTy() && match(Base, m_SpecificFP(2.0)) &&
       (isa<SIToFPInst>(Expo) || isa<UIToFPInst>(Expo)) &&
       hasFloatFn(M, TLI, Ty, LibFunc_ldexp, LibFunc_ldexpf, LibFunc_ldexpl)) {
-    if (Value *ExpoI = getIntToFPVal(Expo, B, TLI->getIntSize()))
-      return copyFlags(*Pow,
-                       emitBinaryFloatFnCall(ConstantFP::get(Ty, 1.0), ExpoI,
-                                             TLI, LibFunc_ldexp, LibFunc_ldexpf,
-                                             LibFunc_ldexpl, B, NoAttrs));
+    if (Value *ExpoI = getIntToFPVal(Expo, B, TLI->getIntSize())) {
+      Constant *One = ConstantFP::get(Ty, 1.0);
+
+      if (Pow->doesNotAccessMemory()) {
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arsenm wrote:

It's multiple lines 

https://github.com/llvm/llvm-project/pull/92363