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

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,31 @@
+; RUN: opt -passes=pre-isel-intrinsic-lowering -S < %s | FileCheck %s
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arsenm wrote:

use update_test_checks 

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