[LV] Add regression test for r297610

[gilr]

Summary

The new test asserts that scalarized memory operations get memcheck metadata added even if the loop is only unrolled.

[hfinkel]

LGTM

test/Transforms/LoopVectorize/unroll-novec-memcheck-metadata.ll

10

Not required currently, but this would be a good place to use FileCheck's new local/global variable feature (r297396). You'd do this by using:

FileCheck --enable-var-scope %s

and then using $MD1 as the regex name, instead of just MD1, because it is intended to be a global variable (one that lives across CHECK-LABEL regions).

test/Transforms/LoopVectorize/unroll-novec-memcheck-metadata.ll

+; RUN: opt < %s -loop-vectorize -force-vector-interleave=2 -force-vector-width=1 -S | FileCheck %s
+
+; Make sure we attach memcheck metadata to scalarized memory operations even if
+; we're only unrolling.
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+; CHECK-LABEL: vector.memcheck:
+; CHECK-LABEL: vector.body:
+; CHECK: load i32, {{.*}} !alias.scope ![[MD1:[0-9]+]]
+; CHECK-LABEL: middle.block:
+; CHECK-DAG: ![[MD1]] = !{![[MD2:[0-9]+]]}
+; CHECK-DAG: ![[MD2]] = distinct !{![[MD2]], ![[MD3:[0-9]+]]}
+; CHECK-DAG: ![[MD3]] = distinct !{![[MD3]], !"LVerDomain"}
+
+; Function Attrs: norecurse nounwind uwtable
+define void @test(i32* nocapture readonly %a, i32* nocapture %b) local_unnamed_addr #0 {
+entry:
+  br label %for.body
+
+for.body:                                         ; preds = %for.body, %entry
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
+  %0 = load i32, i32* %arrayidx, align 4
+  %add = add nsw i32 %0, 77
+  %arrayidx2 = getelementptr inbounds i32, i32* %b, i64 %indvars.iv
+  store i32 %add, i32* %arrayidx2, align 4
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp eq i64 %indvars.iv.next, 10000
+  br i1 %exitcond, label %for.end, label %for.body
+
+for.end:                                          ; preds = %for.body
+  ret void
+}
+
+attributes #0 = { norecurse nounwind uwtable }