Constant expression evaluation: support for constexpr member functions. This
reinstates r144273; a combination of r144333's fix for NoOp rvalue-to-lvalue
casts and some corresponding changes here resolve the regression which that
caused.
This patch also adds support for some additional forms of member function call,
along with additional testing.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@144369 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/SemaCXX/constexpr-nqueens.cpp b/test/SemaCXX/constexpr-nqueens.cpp
new file mode 100644
index 0000000..fbf2045
--- /dev/null
+++ b/test/SemaCXX/constexpr-nqueens.cpp
@@ -0,0 +1,76 @@
+// RUN: %clang_cc1 -std=c++11 -fsyntax-only %s
+
+typedef unsigned long uint64_t;
+
+struct Board {
+ uint64_t State;
+ bool Failed;
+
+ constexpr Board() : State(0), Failed(false) {}
+ constexpr Board(const Board &O) : State(O.State), Failed(O.Failed) {}
+ constexpr Board(uint64_t State, bool Failed = false) :
+ State(State), Failed(Failed) {}
+ constexpr Board addQueen(int Row, int Col) {
+ return Board(State | ((uint64_t)Row << (Col * 4)));
+ }
+ constexpr int getQueenRow(int Col) {
+ return (State >> (Col * 4)) & 0xf;
+ }
+ constexpr bool ok(int Row, int Col) {
+ return okRecurse(Row, Col, 0);
+ }
+ constexpr bool okRecurse(int Row, int Col, int CheckCol) {
+ return Col == CheckCol ? true :
+ getQueenRow(CheckCol) == Row ? false :
+ getQueenRow(CheckCol) == Row + (Col - CheckCol) ? false :
+ getQueenRow(CheckCol) == Row + (CheckCol - Col) ? false :
+ okRecurse(Row, Col, CheckCol + 1);
+ }
+ constexpr bool at(int Row, int Col) {
+ return getQueenRow(Col) == Row;
+ }
+ constexpr bool check(const char *, int=0, int=0);
+};
+
+constexpr Board buildBoardRecurse(int N, int Col, const Board &B);
+constexpr Board buildBoardScan(int N, int Col, int Row, const Board &B);
+constexpr Board tryBoard(const Board &Try,
+ int N, int Col, int Row, const Board &B) {
+ return Try.Failed ? buildBoardScan(N, Col, Row, B) : Try;
+}
+constexpr Board buildBoardScan(int N, int Col, int Row, const Board &B) {
+ return Row == N ? Board(0, true) :
+ B.ok(Row, Col) ?
+ tryBoard(buildBoardRecurse(N, Col + 1, B.addQueen(Row, Col)),
+ N, Col, Row+1, B) :
+ buildBoardScan(N, Col, Row + 1, B);
+}
+constexpr Board buildBoardRecurse(int N, int Col, const Board &B) {
+ return Col == N ? B : buildBoardScan(N, Col, 0, B);
+}
+constexpr Board buildBoard(int N) {
+ return buildBoardRecurse(N, 0, Board());
+}
+
+constexpr Board q8 = buildBoard(8);
+
+constexpr bool Board::check(const char *p, int Row, int Col) {
+ return
+ *p == '\n' ? check(p+1, Row+1, 0) :
+ *p == 'o' ? at(Row, Col) && check(p+1, Row, Col+1) :
+ *p == '-' ? !at(Row, Col) && check(p+1, Row, Col+1) :
+ *p == 0 ? true :
+ false;
+}
+constexpr bool check = q8.check(
+ "o-------\n"
+ "------o-\n"
+ "----o---\n"
+ "-------o\n"
+ "-o------\n"
+ "---o----\n"
+ "-----o--\n"
+ "--o-----\n");
+
+typedef int check_it[1];
+typedef int check_it[check];