[llvm] [AArch64] Preserve SDNode flags when lowering fixed vectors to scalable operations (PR #204616)

[David Sherwood via llvm-commits]

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@@ -0,0 +1,28 @@
+; REQUIRES: asserts
+; RUN: llc -debug-only=isel < %s 2>&1 | FileCheck %s
+
+target triple = "aarch64-unknown-linux-gnu"
+
+define void @usra_disjoint_or32xi8(ptr %a, ptr %b) vscale_range(2,0) #0 {
+; CHECK-LABEL: usra_disjoint_or32xi8:
+; CHECK:    nxv16i8 = USRA_ZZI_B disjoint {{.*}}, {{.*}}, TargetConstant:i32<4>
+  %va = load <32 x i8>, ptr %a
+  %vb = load <32 x i8>, ptr %b
+  %shift = lshr <32 x i8> %vb, splat(i8 4)
+  %res = or disjoint <32 x i8> %va, %shift
+  store <32 x i8> %res, ptr %a
+  ret void
+}
+
+define void @ssra_disjoint_or32xi8(ptr %a, ptr %b) vscale_range(2,0) #0 {
+; CHECK-LABEL: ssra_disjoint_or32xi8:
+    ; CHECK:    nxv16i8 = SSRA_ZZI_B disjoint {{.*}}, {{.*}}, TargetConstant:i32<4>
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david-arm wrote:

nit: whitespace at the start of the line

https://github.com/llvm/llvm-project/pull/204616