Dump results of analysis phase as CSV

Adds the option -Zsave-analysis which will dump the results of syntax and type checking into CSV files. These can be interpreted by tools such as DXR to provide semantic information about Rust programs for code search, cross-reference, etc.

Authored by Nick Cameron and Peter Elmers (@pelmers; including enums, type parameters/generics).

src/librustc/driver/config.rs

@@ -172,7 +172,8 @@ debugging_opts!(
         LTO,
         AST_JSON,
         AST_JSON_NOEXPAND,
-        LS
+        LS,
+        SAVE_ANALYSIS
     ]
     0
 )
@@ -206,7 +207,9 @@ pub fn debugging_opts_map() -> Vec<(&'static str, &'static str, u64)> {
      ("lto", "Perform LLVM link-time optimizations", LTO),
      ("ast-json", "Print the AST as JSON and halt", AST_JSON),
      ("ast-json-noexpand", "Print the pre-expansion AST as JSON and halt", AST_JSON_NOEXPAND),
-     ("ls", "List the symbols defined by a library crate", LS))
+     ("ls", "List the symbols defined by a library crate", LS),
+     ("save-analysis", "Write syntax and type analysis information \
+                        in addition to normal output", SAVE_ANALYSIS))
 }
 
 /// Declare a macro that will define all CodegenOptions fields and parsers all

src/librustc/driver/driver.rs

@@ -87,6 +87,7 @@ pub fn compile_input(sess: Session,
         if stop_after_phase_2(&sess) { return; }
 
         let analysis = phase_3_run_analysis_passes(sess, &expanded_crate, ast_map);
+        phase_save_analysis(&analysis.ty_cx.sess, &expanded_crate, &analysis, outdir);
         if stop_after_phase_3(&analysis.ty_cx.sess) { return; }
         let (tcx, trans) = phase_4_translate_to_llvm(expanded_crate,
                                                      analysis, &outputs);
@@ -370,6 +371,17 @@ pub fn phase_3_run_analysis_passes(sess: Session,
     }
 }
 
+pub fn phase_save_analysis(sess: &Session,
+                           krate: &ast::Crate,
+                           analysis: &CrateAnalysis,
+                           odir: &Option<Path>) {
+    if (sess.opts.debugging_opts & config::SAVE_ANALYSIS) == 0 {
+        return;
+    }
+    time(sess.time_passes(), "save analysis", krate, |krate|
+         middle::save::process_crate(sess, krate, analysis, odir));
+}
+
 pub struct CrateTranslation {
     pub context: ContextRef,
     pub module: ModuleRef,

src/librustc/driver/session.rs

@@ -28,6 +28,7 @@ use syntax::{ast, codemap};
 use std::os;
 use std::cell::{Cell, RefCell};
 
+
 pub struct Session {
     pub targ_cfg: config::Config,
     pub opts: config::Options,

src/librustc/lib.rs

@@ -84,6 +84,7 @@ pub mod middle {
     pub mod expr_use_visitor;
     pub mod dependency_format;
     pub mod weak_lang_items;
+    pub mod save;
 }
 
 pub mod front {