moved crates in lib/ to src/, renamed crates, modified some files' text (#660)

moved crates in lib/ to src/, renamed crates, modified some files' text (#660)

cranelift/filetests/filetests/verifier/defs_dominates_uses.clif

@@ -0,0 +1,16 @@
+test verifier
+
+; Test verification that uses properly dominate defs.
+
+function %non_dominating(i32) -> i32 system_v {
+ebb0(v0: i32):
+    v1 = iadd.i32 v2, v0   ; error: uses value v2 from non-dominating
+    v2 = iadd.i32 v1, v0
+    return v2
+}
+
+function %inst_uses_its_own_values(i32) -> i32 system_v {
+ebb0(v0: i32):
+    v1 = iadd.i32 v1, v0   ; error: uses value v1 from itself
+    return v1
+}