[llvm] [LV] Vectorize histogram operations (PR #99851)

[Florian Hahn via llvm-commits]

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@@ -0,0 +1,44 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt < %s -passes=loop-vectorize,instcombine -enable-histogram-loop-vectorization -force-vector-width=2 -S | FileCheck %s
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+
+define void @simple_histogram(ptr noalias %buckets, ptr readonly %indices, i64 %N) #0 {
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fhahn wrote:

might be worth adding a comment here saying what we expect here, i.e. no vectorization as (generic) target doesn't support histogram intrinsics?

https://github.com/llvm/llvm-project/pull/99851