[LV] Pre-commit test for narrow-store-user-mask-op

Author: artagnon

llvm/test/Transforms/LoopVectorize/X86/narrow-to-single-scalar.ll

@@ -0,0 +1,32 @@
+; REQUIRES: asserts
+; RUN: not --crash opt -p loop-vectorize -mcpu=skylake -S %s
+
+target triple = "x86_64-unknown-linux-gnu"
+
+@p = external global [3952 x i8], align 8
+@q = external global [3952 x i8], align 8
+
+define void @narrow_store_user_mask_operand(i32 %x) {
+entry:
+  br label %loop.ph
+
+loop.ph:
+  %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop.tail ]
+  %x.pos = icmp sgt i32 %x, 0
+  br i1 %x.pos, label %loop.body, label %loop.tail
+
+loop.body:
+  %ld.p = load double, ptr @p
+  %gep.q.iv = getelementptr double, ptr @q, i64 %iv
+  %gep.q.iv.8 = getelementptr i8, ptr %gep.q.iv, i64 -8
+  store double %ld.p, ptr %gep.q.iv.8
+  br label %loop.tail
+
+loop.tail:
+  %iv.next = add i64 %iv, 1
+  %ec = icmp eq i64 %iv, 1
+  br i1 %ec, label %exit, label %loop.ph
+
+exit:
+  ret void
+}