Add a verifier

The current implementation only performs a few basic checks.

cranelift/src/tools/Cargo.lock

@@ -21,6 +21,9 @@ dependencies = [
 [[package]]
 name = "cretonne"
 version = "0.0.0"
+dependencies = [
+ "regex 0.1.71 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "cretonne-reader"

cranelift/src/tools/tests/verifier.rs

@@ -0,0 +1,66 @@
+extern crate cretonne;
+extern crate cton_reader;
+extern crate glob;
+extern crate regex;
+
+use std::env;
+use glob::glob;
+use regex::Regex;
+use std::fs::File;
+use std::io::Read;
+use self::cton_reader::parser::Parser;
+use self::cretonne::verifier::Verifier;
+
+/// Compile a function and run verifier tests based on specially formatted
+/// comments in the [function's] source.
+fn verifier_tests_from_source(function_source: &str) {
+    let func_re = Regex::new("^[ \t]*function.*").unwrap();
+    let err_re = Regex::new(";[ \t]*Err\\((.*)+\\)").unwrap();
+
+    // Each entry corresponds to an optional regular expression, where
+    // the index corresponds to the function offset in our source code.
+    // If no error is expected for a given function its entry will be
+    // set to None.
+    let mut verifier_results = Vec::new();
+    for line in function_source.lines() {
+        if func_re.is_match(line) {
+            match err_re.captures(line) {
+                Some(caps) => {
+                    verifier_results.push(Some(Regex::new(caps.at(1).unwrap()).unwrap()));
+                },
+                None => {
+                    verifier_results.push(None);
+                },
+            };
+        }
+    }
+
+    // Run the verifier against each function and compare the output
+    // with the expected result (as determined above).
+    for (i, func) in Parser::parse(function_source).unwrap().into_iter().enumerate() {
+        let result = Verifier::new(&func).run();
+        match verifier_results[i] {
+            Some(ref re) => {
+                assert_eq!(re.is_match(&result.err().unwrap()), true);
+            },
+            None => {
+                assert_eq!(result, Ok(()));
+            }
+        }
+    }
+}
+
+#[test]
+fn test_all() {
+    let testdir = format!("{}/tests/verifier_testdata/*.cton",
+                          env::current_dir().unwrap().display());
+
+    for entry in glob(&testdir).unwrap() {
+        let path = entry.unwrap();
+        println!("Testing {:?}", path);
+        let mut file = File::open(&path).unwrap();
+        let mut buffer = String::new();
+        file.read_to_string(&mut buffer).unwrap();
+        verifier_tests_from_source(&buffer);
+    }
+}

cranelift/src/tools/tests/verifier_testdata/bad_layout.cton

@@ -0,0 +1,17 @@
+function test(i32) {    ; Err(terminating)
+    ebb0(v0: i32):
+        jump ebb1
+        return
+    ebb1:
+        jump ebb2
+        brz v0, ebb3
+    ebb2:
+        jump ebb3
+    ebb3:
+        return
+}
+
+function test(i32) {    ; Ok
+    ebb0(v0: i32):
+        return
+}