[AArch64] Set default schedule of load-acquire RCpc instructions. (#172881)

This patch sets the default schedule of RCpc load-acquires to WriteLD,
same as it's done for rcpc-immo load-acquires.

llvm/lib/Target/AArch64/AArch64InstrFormats.td

diff --git a/llvm/lib/Target/AArch64/AArch64InstrFormats.td b/llvm/lib/Target/AArch64/AArch64InstrFormats.td
index 4d3a622..97bfa9e 100644
--- a/llvm/lib/Target/AArch64/AArch64InstrFormats.td
+++ b/llvm/lib/Target/AArch64/AArch64InstrFormats.td
@@ -2091,7 +2091,7 @@
 let mayLoad = 1 in
 class RCPCLoad<bits<2> sz, string asm, RegisterClass RC>
   : I<(outs RC:$Rt), (ins GPR64sp0:$Rn), asm, "\t$Rt, [$Rn]", "", []>,
-  Sched<[]> {
+  Sched<[WriteLD]> {
   bits<5> Rn;
   bits<5> Rt;
   let Inst{31-30} = sz;

llvm/test/CodeGen/AArch64/rcpc3-sve.ll

diff --git a/llvm/test/CodeGen/AArch64/rcpc3-sve.ll b/llvm/test/CodeGen/AArch64/rcpc3-sve.ll
index 6b03e5d..d4c80d8 100644
--- a/llvm/test/CodeGen/AArch64/rcpc3-sve.ll
+++ b/llvm/test/CodeGen/AArch64/rcpc3-sve.ll
@@ -8,8 +8,8 @@
 define hidden <vscale x 2 x i64> @test_load_sve_lane0(ptr nocapture noundef readonly %a, <vscale x 2 x i64> noundef %b) local_unnamed_addr {
 ; CHECK-LABEL: test_load_sve_lane0:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    ldapr x8, [x0]
 ; CHECK-NEXT:    ptrue p0.d, vl1
+; CHECK-NEXT:    ldapr x8, [x0]
 ; CHECK-NEXT:    mov z0.d, p0/m, x8
 ; CHECK-NEXT:    ret
   %1 = load atomic i64, ptr %a acquire, align 8