Auto merge of #264 - fitzgen:emit-ir, r=emilio

Add an option to emit our ir for debugging

Similar to our ability to emit the clang AST, this adds an option to
emit our IR for debugging purposes.

This can wait to land until after #204 is merged.

r? @emilio

Author: bors-servo

libbindgen/src/codegen/mod.rs

@@ -1892,6 +1892,13 @@ pub fn codegen(context: &mut BindgenContext) -> Vec<P<ast::Item>> {
 
         let whitelisted_items: ItemSet = context.whitelisted_items().collect();
 
+        if context.options().emit_ir {
+            for &id in whitelisted_items.iter() {
+                let item = context.resolve_item(id);
+                println!("ir: {:?} = {:#?}", id, item);
+            }
+        }
+
         for &id in whitelisted_items.iter() {
             let item = context.resolve_item(id);
 

libbindgen/src/lib.rs

@@ -225,6 +225,12 @@ impl Builder {
         self
     }
 
+    /// Emit IR.
+    pub fn emit_ir(mut self) -> Builder {
+        self.options.emit_ir = true;
+        self
+    }
+
     /// Enable C++ namespaces.
     pub fn enable_cxx_namespaces(mut self) -> Builder {
         self.options.enable_cxx_namespaces = true;
@@ -314,6 +320,9 @@ pub struct BindgenOptions {
     /// True if we should dump the Clang AST for debugging purposes.
     pub emit_ast: bool,
 
+    /// True if we should dump our internal IR for debugging purposes.
+    pub emit_ir: bool,
+
     /// True if we should ignore functions and only generate bindings for
     /// structures, types, and methods.
     pub ignore_functions: bool,
@@ -380,6 +389,7 @@ impl Default for BindgenOptions {
             builtins: false,
             links: vec![],
             emit_ast: false,
+            emit_ir: false,
             ignore_functions: false,
             ignore_methods: false,
             derive_debug: true,

src/options.rs

@@ -52,6 +52,9 @@ pub fn builder_from_flags<I>(args: I)
             Arg::with_name("emit-clang-ast")
                 .long("emit-clang-ast")
                 .help("Output the Clang AST for debugging purposes."),
+            Arg::with_name("emit-ir")
+                .long("emit-ir")
+                .help("Output our internal IR for debugging purposes."),
             Arg::with_name("enable-cxx-namespaces")
                 .long("enable-cxx-namespaces")
                 .help("Enable support for C++ namespaces."),
@@ -183,6 +186,10 @@ pub fn builder_from_flags<I>(args: I)
         builder = builder.emit_clang_ast();
     }
 
+    if matches.is_present("emit-ir") {
+        builder = builder.emit_ir();
+    }
+
     if matches.is_present("enable-cxx-namespaces") {
         builder = builder.enable_cxx_namespaces();
     }