Move integration tests into src/tools/tests.

The integration tests use both libcretonne and libreader, so moving them avoids
the circular dev-dependency.

Also go back to building everything under src/tools/target to avoid rebuilding
the libraries when cargo is invoked in different subdirectories. This speeds up
test-all.sh quite a bit.

Finally, skip the pure debug build. We build "cargo test" and "cargo build
--release" which should cover everything we need.

src/tools/tests/dominator_tree.rs

@@ -0,0 +1,60 @@
+extern crate cretonne;
+extern crate cton_reader;
+
+use self::cton_reader::parser::Parser;
+use self::cretonne::ir::entities::Ebb;
+use self::cretonne::cfg::ControlFlowGraph;
+use self::cretonne::dominator_tree::DominatorTree;
+
+fn test_dominator_tree(function_source: &str, idoms: Vec<u32>) {
+    let func = &Parser::parse(function_source).unwrap()[0];
+    let cfg = ControlFlowGraph::new(&func);
+    let dtree = DominatorTree::new(&cfg);
+    assert_eq!(dtree.ebbs().collect::<Vec<_>>().len(), idoms.len());
+    for (i, j) in idoms.iter().enumerate() {
+        let ebb = Ebb::with_number(i.clone() as u32);
+        let idom = Ebb::with_number(*j);
+        assert_eq!(dtree.idom(ebb.unwrap()), idom);
+    }
+}
+
+#[test]
+fn basic() {
+    test_dominator_tree("
+        function test(i32) {
+            ebb0(v0: i32):
+                jump ebb1
+            ebb1:
+                brz v0, ebb3
+                jump ebb2
+            ebb2:
+                jump ebb3
+            ebb3:
+                return
+        }
+    ", vec![0, 0, 1, 1]);
+}
+
+#[test]
+fn loops() {
+    test_dominator_tree("
+        function test(i32) {
+            ebb0(v0: i32):
+                brz v0, ebb1
+                jump ebb2
+            ebb1:
+                jump ebb3
+            ebb2:
+                brz v0, ebb4
+                jump ebb5
+            ebb3:
+                jump ebb4
+            ebb4:
+                brz v0, ebb3
+                jump ebb5
+            ebb5:
+                brz v0, ebb4
+                return
+        }
+    ", vec![0, 0, 0, 0, 0, 0]);
+}