Add option to just print out function signatures (#1185)

README.md

@@ -43,6 +43,7 @@ string which can contain any of the following flags:
 - `--single_func <name>`: the name of a specific function you want to analyze.
 - `--body_analysis_timeout <seconds>`: the maximum number of seconds to spend analyzing a function body.
 - `--call_graph_config <path_to_config>`: path to configuration file for call graph generator (see [Call Graph Generator documentation](documentation/CallGraph.md)). No call graph will be generated if this is not specified.
+- `--print_function_names`: just print the source location and fully qualified function signature of every function.
 - `--`: any arguments after this marker are passed on to rustc.
 
 You can get some insight into the inner workings of MIRAI by setting the verbosity level of log output to one of 

checker/Cargo.toml

@@ -29,7 +29,7 @@ doctest = false # and no doc tests
 [dependencies]
 bincode = { version = "*", features = ["i128"] }
 cargo_metadata = "*"
-clap = "*"
+clap = "3.2"
 env_logger = "*"
 fs2 = "*"
 itertools = "*"

checker/src/callbacks.rs

@@ -12,6 +12,7 @@ use crate::options::Options;
 use crate::summaries::PersistentSummaryCache;
 
 use crate::type_visitor::TypeCache;
+use crate::utils;
 use log::info;
 use log_derive::*;
 use rustc_driver::Compilation;
@@ -128,6 +129,16 @@ impl MiraiCallbacks {
     /// Analyze the crate currently being compiled, using the information given in compiler and tcx.
     #[logfn(TRACE)]
     fn analyze_with_mirai<'tcx>(&mut self, compiler: &interface::Compiler, tcx: TyCtxt<'tcx>) {
+        if self.options.print_function_names {
+            for local_def_id in tcx.hir().body_owners() {
+                let def_id = local_def_id.to_def_id();
+                let span = tcx.def_span(def_id);
+                eprint!("{:?}: ", span);
+                let name = utils::def_id_as_qualified_name_str(tcx, def_id);
+                eprintln!("{}", name);
+            }
+            return;
+        }
         let output_dir = String::from(self.output_directory.to_str().expect("valid string"));
         let summary_store_path = if std::env::var("MIRAI_SHARE_PERSISTENT_STORE").is_ok() {
             output_dir

checker/src/options.rs

@@ -54,7 +54,11 @@ fn make_options_parser<'help>(running_test_harness: bool) -> Command<'help> {
             .long("call_graph_config")
             .takes_value(true)
             .help("Path call graph config.")
-            .long_help(r#"Path to a JSON file that configures call graph output. Please see the documentation for details (https://github.com/facebookexperimental/MIRAI/blob/main/documentation/CallGraph.md)."#));
+            .long_help(r#"Path to a JSON file that configures call graph output. Please see the documentation for details (https://github.com/facebookexperimental/MIRAI/blob/main/documentation/CallGraph.md)."#))
+        .arg(Arg::new("print_function_names")
+            .long("print_function_names")
+            .takes_value(false)
+            .help("Just print out the signatures of functions in the crate"));
     if running_test_harness {
         parser = parser.arg(Arg::new("test_only")
             .long("test_only")
@@ -76,6 +80,7 @@ pub struct Options {
     pub max_analysis_time_for_crate: u64,
     pub statistics: bool,
     pub call_graph_config: Option<String>,
+    pub print_function_names: bool,
 }
 
 /// Represents diag level.
@@ -213,6 +218,9 @@ impl Options {
         if matches.is_present("call_graph_config") {
             self.call_graph_config = matches.value_of("call_graph_config").map(|s| s.to_string());
         }
+        if matches.is_present("print_function_names") {
+            self.print_function_names = true;
+        }
         args[rustc_args_start..].to_vec()
     }
 }

checker/src/utils.rs

@@ -433,6 +433,32 @@ fn push_component_name(component_data: DefPathData, target: &mut String) {
     };
 }
 
+/// Returns a human readable string representation of the item defined by def_id.
+/// This is different from summary_key_str, in that it does not mangle type argument
+/// values into the item name and furthermore includes parameter types and the
+/// return types of functions. This is intended for use in call graphs.
+pub fn def_id_as_qualified_name_str(tcx: TyCtxt<'_>, def_id: DefId) -> Rc<str> {
+    let mut name = format!("/{}/", crate_name(tcx, def_id));
+    name.push_str(&tcx.def_path_str(def_id));
+    let fn_ty = tcx.type_of(def_id);
+    if fn_ty.is_fn() {
+        name.push('(');
+        let fn_sig = fn_ty.fn_sig(tcx).skip_binder();
+        let mut first = true;
+        for param_ty in fn_sig.inputs() {
+            if first {
+                first = false;
+            } else {
+                name.push(',')
+            }
+            name.push_str(&format!("{:?}", param_ty));
+        }
+        name.push_str(")->");
+        name.push_str(&format!("{:?}", fn_sig.output()));
+    }
+    Rc::from(name.as_str())
+}
+
 /// Returns a readable display name for a DefId. This name may not be unique.
 pub fn def_id_display_name(tcx: TyCtxt<'_>, def_id: DefId) -> String {
     struct PrettyDefId<'tcx>(DefId, TyCtxt<'tcx>);