[llvm] PreISelIntrinsicLowering: Lower llvm.exp to a loop if scalable vec arg (PR #117568)

[Matt Arsenault via llvm-commits]

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@@ -453,6 +454,11 @@ bool PreISelIntrinsicLowering::lowerIntrinsics(Module &M) const {
     case Intrinsic::objc_sync_exit:
       Changed |= lowerObjCCall(F, "objc_sync_exit");
       break;
+    case Intrinsic::exp:
+      Changed |= forEachCall(F, [&](CallInst *CI) {
+        return lowerUnaryMathIntrinsicWithScalableVecArgAsLoop(M, CI);
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arsenm wrote:

This probably shouldn't be unconditional? Depends on the target legality? 

https://github.com/llvm/llvm-project/pull/117568