Implement !if, analogous to $(if) in GNU make.

llvm-svn: 71815

1 files changed, 20 insertions, 0 deletions

diff --git a/llvm/test/TableGen/if.td b/llvm/test/TableGen/if.td
new file mode 100644
index 00000000000..3c45d95eb20
--- /dev/null
+++ b/llvm/test/TableGen/if.td
@@ -0,0 +1,20 @@
+// RUN: tblgen %s | grep {1, 2, 3} | count 4
+// RUN: tblgen %s | grep {4, 5, 6} | count 2
+
+class A<list<list<int>> vals> {
+  list<int> first = vals[0];
+  list<int> rest  = !if(!null(!cdr(vals)), vals[0], vals[1]);
+}
+
+def One : A<[[1,2,3]]>;
+def Two : A<[[1,2,3],[4,5,6]]>;
+
+class B<list<int> v> {
+  list<int> vals = v;
+}
+
+class BB<list<list<int>> vals> : B<!if(!null(!cdr(vals)), vals[0], vals[1])>;
+class BBB<list<list<int>> vals> : BB<vals>;
+
+def OneB : BBB<[[1,2,3]]>;
+def TwoB : BBB<[[1,2,3],[4,5,6]]>;