Add support for using the `!if' operator when initializing variables:

  class A<bit a, bits<3> x, bits<3> y> {
    bits<3> z;
    let z = !if(a, x, y);
  }

The variable z will get the value of x when 'a' is 1 and 'y' when a is '0'.

llvm-svn: 121666

1 files changed, 27 insertions, 3 deletions

diff --git a/llvm/test/TableGen/if.td b/llvm/test/TableGen/if.td
index 0bac0bac3e9..bff927802bf 100644
--- a/llvm/test/TableGen/if.td
+++ b/llvm/test/TableGen/if.td
@@ -1,14 +1,38 @@
-// RUN: tblgen %s | grep {\\\[1, 2, 3\\\]} | count 4
-// RUN: tblgen %s | grep {\\\[4, 5, 6\\\]} | count 2
+// RUN: tblgen %s | FileCheck %s
 // XFAIL: vg_leak
 
+// Support for an `!if' operator as part of a `let' statement.
+// CHECK:      class C
+// CHECK-NEXT: bits<16> n = { ?, ?, ?, ?, ?, ?, ?, !if({ C:x{2} }, 0, 1), !if({ C:x{2} }, 1, 1), !if({ C:x{2} }, 0, 0), !if({ C:x{1} }, C:y{3}, 0), !if({ C:x{1} }, C:y{2}, 1), !if({ C:x{0} }, C:y{3}, C:z), !if({ C:x{0} }, C:y{2}, C:y{2}), !if({ C:x{0} }, C:y{1}, C:y{1}), !if({ C:x{0} }, C:y{0}, C:y{0}) };
+class C<bits<3> x, bits<4> y, bit z> {
+  bits<16> n;
+
+  let n{8-6} = !if(x{2}, 0b010, 0b110);
+  let n{5-4} = !if(x{1}, y{3-2}, {0, 1});
+  let n{3-0} = !if(x{0}, y{3-0}, {z, y{2}, y{1}, y{0}});
+}
+
+// CHECK:      def One
+// CHECK-NEXT: list<int> first = [1, 2, 3];
+// CHECK-NEXT: list<int> rest = [1, 2, 3];
+
+// CHECK:      def OneB
+// CHECK-NEXT: list<int> vals = [1, 2, 3];
+
+// CHECK:      def Two
+// CHECK-NEXT: list<int> first = [1, 2, 3];
+// CHECK-NEXT: list<int> rest = [4, 5, 6];
+
+// CHECK:      def TwoB
+// CHECK-NEXT: list<int> vals = [4, 5, 6];
+
 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]]>;
+def Two : A<[[1,2,3], [4,5,6]]>;
 
 class B<list<int> v> {
   list<int> vals = v;