[llvm] [AArch64][CodeGen] Fold tbx(splat(0), table, idxs) to tbl(table, idxs) (PR #214268)

[Harry Ramsey via llvm-commits]

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@@ -0,0 +1,48 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=aarch64 -mattr=+neon < %s | FileCheck %s
+
+define <16 x i8> @test_tbx1_zero_splat(<16 x i8> %tbl, <16 x i8> %idx) {
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Harry-Ramsey wrote:

There are also <8 x i8> variants of `TBL` and `TBX` so it would be ideal to have some tests for those as well alongside your <16 x i8> tests.

https://github.com/llvm/llvm-project/pull/214268