[llvm] [LoopVectorize] Vectorize select-cmp reduction pattern for increasing integer induction variable (PR #67812)

[David Sherwood via llvm-commits]

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@@ -1,10 +1,193 @@
-; RUN: opt -passes=loop-vectorize -force-vector-interleave=1 -force-vector-width=4 -S < %s | FileCheck %s --check-prefix=CHECK
-; RUN: opt -passes=loop-vectorize -force-vector-interleave=4 -force-vector-width=4 -S < %s | FileCheck %s --check-prefix=CHECK
-; RUN: opt -passes=loop-vectorize -force-vector-interleave=4 -force-vector-width=1 -S < %s | FileCheck %s --check-prefix=CHECK
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt -passes=loop-vectorize -force-vector-interleave=1 -force-vector-width=4 -S < %s | FileCheck %s --check-prefix=CHECK-VF4IC1 --check-prefix=CHECK
+; RUN: opt -passes=loop-vectorize -force-vector-interleave=4 -force-vector-width=4 -S < %s | FileCheck %s --check-prefix=CHECK-VF4IC4 --check-prefix=CHECK
+; RUN: opt -passes=loop-vectorize -force-vector-interleave=4 -force-vector-width=1 -S < %s | FileCheck %s --check-prefix=CHECK-VF1IC4 --check-prefix=CHECK
 
 define i64 @select_icmp_const_1(ptr %a, i64 %n) {
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david-arm wrote:

Both `@select_icmp_const_1` and `@select_icmp_const_2` look similar to test `select_icmp_nuw_nsw` in Transforms/LoopVectorize/iv-select-cmp-no-wrap.ll.

Also, I see the only difference between `@select_icmp_const_1` and `@select_icmp_const_2` is the operands to the select are swapped. I'm not sure having both versions really adds much value. Perhaps you can remove both of them and leave the one in iv-select-cmp-no-wrap.ll

https://github.com/llvm/llvm-project/pull/67812