[llvm] [IA]: Construct (de)interleave4 out of (de)interleave2 (PR #89276)

[Paul Walker via llvm-commits]

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@@ -0,0 +1,78 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=aarch64--linux-gnu -mattr=+sve < %s | FileCheck %s
+
+%struct.xyzt = type { i32, i32, i32, i32 }
+
+define dso_local void @loop_xyzt(ptr noalias nocapture noundef writeonly %dst, ptr nocapture noundef readonly %a, ptr nocapture noundef readonly %b) {
+; CHECK-LABEL: loop_xyzt:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    ptrue p0.s
+; CHECK-NEXT:    cntw x10
+; CHECK-NEXT:    mov x8, xzr
+; CHECK-NEXT:    mov w9, #1024 // =0x400
+; CHECK-NEXT:    neg x10, x10
+; CHECK-NEXT:    rdvl x11, #4
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paulwalker-arm wrote:

Please can you simplify the tests to the minimum required to test the new code.  In this instance there should be no need for any loop, just straight line code for a single load with interleave.

https://github.com/llvm/llvm-project/pull/89276