[AArch64] Add test case for D53229. NFC

llvm-svn: 345566

llvm/test/CodeGen/AArch64/bitcast-promote-widen.ll

@@ -0,0 +1,31 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=aarch64-unknown-linux-gnu | FileCheck %s
+
+; Test cases of bitcasts where one type needs to be widened and one needs to be promoted.
+
+define <2 x i16> @bitcast_v2i16_v2f16(<2 x half> %x) {
+; CHECK-LABEL: bitcast_v2i16_v2f16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    sub sp, sp, #16 // =16
+; CHECK-NEXT:    .cfi_def_cfa_offset 16
+; CHECK-NEXT:    // kill: def $d0 killed $d0 def $q0
+; CHECK-NEXT:    str s0, [sp, #12]
+; CHECK-NEXT:    ldrh w8, [sp, #12]
+; CHECK-NEXT:    ldrh w9, [sp, #14]
+; CHECK-NEXT:    fmov s0, w8
+; CHECK-NEXT:    mov v0.s[1], w9
+; CHECK-NEXT:    // kill: def $d0 killed $d0 killed $q0
+; CHECK-NEXT:    add sp, sp, #16 // =16
+; CHECK-NEXT:    ret
+  %y = bitcast <2 x half> %x to <2 x i16>
+  ret <2 x i16> %y
+}
+
+define <2 x half> @bitcast_v2f16_v2i16(<2 x i16> %x) {
+; CHECK-LABEL: bitcast_v2f16_v2i16:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    uzp1 v0.4h, v0.4h, v0.4h
+; CHECK-NEXT:    ret
+  %y = bitcast <2 x i16> %x to <2 x half>
+  ret <2 x half> %y
+}