[llvm] [VPlan] Account for dead FOR splice simplification in cost model (PR #131486)

[Mel Chen via llvm-commits]

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@@ -0,0 +1,111 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -p loop-vectorize -S %s | FileCheck %s
+
+; If a FOR isn't used the VPInstruction::FirstOrderRecurrenceSplice will be dead
+; and won't be costed in the VPlan cost model. Make sure we account for this
+; simplifcation in comparison to the legacy cost model.
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
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Mel-Chen wrote:

nit: Could we remove target datalayout?

https://github.com/llvm/llvm-project/pull/131486