[llvm] [AArch64][GlobalISel] Adopt dup(load) -> LD1R patterns from SelectionDAG (PR #66914)

[Amara Emerson via llvm-commits]

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@@ -13794,8 +13794,9 @@ define <16 x i8> @test_v16i8_post_imm_ld1r(ptr %bar, ptr %ptr) {
 ;
 ; CHECK-GISEL-LABEL: test_v16i8_post_imm_ld1r:
 ; CHECK-GISEL:       ; %bb.0:
-; CHECK-GISEL-NEXT:    ld1r.16b { v0 }, [x0], #1
-; CHECK-GISEL-NEXT:    str x0, [x1]
+; CHECK-GISEL-NEXT:    ld1r.16b { v0 }, [x0]
+; CHECK-GISEL-NEXT:    add x8, x0, #1
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aemerson wrote:

This size increase is due to not falling back right? If so we should add the function to the fallback NOT checks at the top of the test.

https://github.com/llvm/llvm-project/pull/66914