1 files changed, 34 insertions, 0 deletions
diff --git a/testsuite/tests/perf/compiler/genManyAlternatives b/testsuite/tests/perf/compiler/genManyAlternatives
new file mode 100755
index 0000000000..1035425bd4
--- /dev/null
+++ b/testsuite/tests/perf/compiler/genManyAlternatives
@@ -0,0 +1,34 @@
+SIZE=1000
+MODULE=ManyAlternatives
+
+# Generates a module with a large number of alternatives that looks
+# like this:
+#
+#   module ManyAlternatives where
+#
+#   data A1000 = A0
+#     | A0001
+#     | A0002
+#     ...
+#     | A1000
+#
+#   f :: A -> Int
+#   f A0001 = 1990001
+#   f A0002 = 1990002
+#   ...
+#   f A1000 = 1991000
+#
+# The point of this test is to check if we don't regress on #14667 reintroducing
+# some code that's quadratic in the number of alternatives.
+
+echo "module $MODULE where" > $MODULE.hs
+echo >> $MODULE.hs
+echo "data A$SIZE = A0" >> $MODULE.hs
+for i in $(seq -w 1 $SIZE); do
+  echo "  | A$i" >> $MODULE.hs
+done
+echo >> $MODULE.hs
+echo "f :: A$SIZE -> Int" >> $MODULE.hs
+for i in $(seq -w 1 $SIZE); do
+  echo "f A$i = 199$i" >> $MODULE.hs
+done