1 files changed, 61 insertions, 0 deletions
diff --git a/test/Analysis/IVUsers/quadradic-exit-value.ll b/test/Analysis/IVUsers/quadradic-exit-value.ll
new file mode 100644
index 0000000000000..214afcb2ffa76
--- /dev/null
+++ b/test/Analysis/IVUsers/quadradic-exit-value.ll
@@ -0,0 +1,61 @@
+; This test ensures that IVUsers works correctly in the legacy pass manager
+; without LCSSA and in the specific ways that some of its users (LSR) require.
+;
+; FIXME: We need some way to match the precision here in the new PM where loop
+; passes *always* work on LCSSA. This should stop using a different set of
+; checks at that point.
+
+; RUN: opt < %s -analyze -iv-users | FileCheck %s --check-prefixes=CHECK,CHECK-NO-LCSSA
+; RUN: opt < %s -disable-output -passes='print<ivusers>' 2>&1 | FileCheck %s
+
+; Provide legal integer types.
+target datalayout = "n8:16:32:64"
+
+; The value of %r is dependent on a polynomial iteration expression.
+;
+; CHECK-LABEL: IV Users for loop %foo.loop
+; CHECK-NO-LCSSA: {1,+,3,+,2}<%foo.loop>
+define i64 @foo(i64 %n) {
+entry:
+  br label %foo.loop
+
+foo.loop:
+  %indvar = phi i64 [ 0, %entry ], [ %indvar.next, %foo.loop ]
+  %indvar.next = add i64 %indvar, 1
+  %c = icmp eq i64 %indvar.next, %n
+  br i1 %c, label %exit, label %foo.loop
+
+exit:
+  %r = mul i64 %indvar.next, %indvar.next
+  ret i64 %r
+}
+
+; PR15470: LSR miscompile. The test2 function should return '1'.
+;
+; SCEV does not know how to denormalize chained recurrences, so make
+; sure they aren't marked as post-inc users.
+;
+; CHECK-LABEL: IV Users for loop %test2.loop
+; CHECK-NO-LCSSA: %sext.us = {0,+,(16777216 + (-16777216 * %sub.us))<nuw><nsw>,+,33554432}<%test2.loop> in %f = ashr i32 %sext.us, 24
+define i32 @test2() {
+entry:
+  br label %test2.loop
+
+test2.loop:
+  %inc1115.us = phi i32 [ 0, %entry ], [ %inc11.us, %test2.loop ]
+  %inc11.us = add nsw i32 %inc1115.us, 1
+  %cmp.us = icmp slt i32 %inc11.us, 2
+  br i1 %cmp.us, label %test2.loop, label %for.end
+
+for.end:
+  %tobool.us = icmp eq i32 %inc1115.us, 0
+  %sub.us = select i1 %tobool.us, i32 0, i32 0
+  %mul.us = shl i32 %inc1115.us, 24
+  %sub.cond.us = sub nsw i32 %inc1115.us, %sub.us
+  %sext.us = mul i32 %mul.us, %sub.cond.us
+  %f = ashr i32 %sext.us, 24
+  br label %exit
+
+exit:
+  ret i32 %f
+}