[llvm] [AArch64] Optimize when storing symmetry constants (PR #93717)

[via llvm-commits]

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@@ -93,3 +93,134 @@ define i64 @testuu0xf555f555f555f555() {
 ; CHECK-NEXT:    ret
   ret i64 u0xf555f555f555f555
 }
+
+define void @test_store_0x1234567812345678(ptr %x) {
+; CHECK-LABEL: test_store_0x1234567812345678:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    mov x8, #22136 // =0x5678
+; CHECK-NEXT:    movk x8, #4660, lsl #16
+; CHECK-NEXT:    stp w8, w8, [x0, #32]
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ParkHanbum wrote:

ah! I found it!! how about use 32-bit register like `str` do it? using`STPXi` instead `STPWi` can fix easier. 

https://github.com/llvm/llvm-project/pull/93717