Add test case for merging of chained stores of mismatched type.

llvm-svn: 298293

llvm/test/CodeGen/AArch64/pr27816.ll

@@ -0,0 +1,48 @@
+; RUN: llc %s -mtriple=aarch64 -o - | FileCheck %s
+
+%struct.A = type { i8, i8, i8, i8, i8, i8, i8, i8, i32 }
+
+; The existence of the final i32 value should not prevent the i8s from
+; being merged.
+
+; CHECK-LABEL: @merge_const_store
+; CHECK-NOT: strb
+; CHECK: str x8,  [x1]
+; CHECK-NOT: strb
+; CHECK: str wzr, [x1, #8]
+; CHECK-NOT: strb
+define void @merge_const_store(i32 %count, %struct.A* nocapture %p)  {
+  %1 = icmp sgt i32 %count, 0
+  br i1 %1, label %.lr.ph, label %._crit_edge
+.lr.ph:
+  %i.02 = phi i32 [ %add, %.lr.ph ], [ 0, %0 ]
+  %.01 = phi %struct.A* [ %addr, %.lr.ph ], [ %p, %0 ]
+  %a2 = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 0
+  store i8 1, i8* %a2, align 1
+  %a3 = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 1
+  store i8 2, i8* %a3, align 1
+  %a4 = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 2
+  store i8 3, i8* %a4, align 1
+  %a5 = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 3
+  store i8 4, i8* %a5, align 1
+  %a6 = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 4
+  store i8 5, i8* %a6, align 1
+  %a7 = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 5
+  store i8 6, i8* %a7, align 1
+  %a8 = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 6
+  store i8 7, i8* %a8, align 1
+  %a9 = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 7
+  store i8 8, i8* %a9, align 1
+
+  ;
+  %addr_last = getelementptr inbounds %struct.A, %struct.A* %.01, i64 0, i32 8
+  store i32 0, i32* %addr_last, align 4
+
+
+  %add = add nsw i32 %i.02, 1
+  %addr = getelementptr inbounds %struct.A, %struct.A* %.01, i64 1
+  %exitcond = icmp eq i32 %add, %count
+  br i1 %exitcond, label %._crit_edge, label %.lr.ph
+._crit_edge:
+  ret void
+}