---

yaml
---
r: 191797
b: refs/heads/snap-stage3
c: c109189
h: refs/heads/master
i:
  191795: 2223f41
v: v3

Author: bors

[refs]

@@ -1,7 +1,7 @@
 ---
 refs/heads/master: 809a554fca2d0ebc2ba50077016fe282a4064752
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
-refs/heads/snap-stage3: 0947f4076ddbf5c0db63d60c19f28b6b79023638
+refs/heads/snap-stage3: c10918905fda1344e78bc16e6e73294d096ee97d
 refs/heads/try: ce76bff75603a754d092456285ff455eb871633d
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d

branches/snap-stage3/src/libarena/lib.rs

@@ -42,8 +42,9 @@ extern crate alloc;
 
 use std::cell::{Cell, RefCell};
 use std::cmp;
-use std::intrinsics::{TyDesc, get_tydesc};
 use std::intrinsics;
+#[cfg(stage0)] // SNAP 270a677
+use std::intrinsics::{get_tydesc, TyDesc};
 use std::marker;
 use std::mem;
 #[cfg(stage0)]
@@ -186,6 +187,27 @@ fn un_bitpack_tydesc_ptr(p: usize) -> (*const TyDesc, bool) {
     ((p & !1) as *const TyDesc, p & 1 == 1)
 }
 
+// HACK(eddyb) TyDesc replacement using a trait object vtable.
+// This could be replaced in the future with a custom DST layout,
+// or `&'static (drop_glue, size, align)` created by a `const fn`.
+#[cfg(not(stage0))] // SNAP 270a677
+struct TyDesc {
+    drop_glue: fn(*const i8),
+    size: usize,
+    align: usize
+}
+
+#[cfg(not(stage0))] // SNAP 270a677
+unsafe fn get_tydesc<T>() -> *const TyDesc {
+    use std::raw::TraitObject;
+
+    let ptr = &*(1 as *const T);
+
+    // Can use any trait that is implemented for all types.
+    let obj = mem::transmute::<&marker::MarkerTrait, TraitObject>(ptr);
+    obj.vtable as *const TyDesc
+}
+
 impl<'longer_than_self> Arena<'longer_than_self> {
     fn chunk_size(&self) -> usize {
         self.copy_head.borrow().capacity()

branches/snap-stage3/src/libcore/intrinsics.rs

@@ -44,10 +44,12 @@
 
 use marker::Sized;
 
+#[cfg(stage0)] // SNAP 270a677
 pub type GlueFn = extern "Rust" fn(*const i8);
 
 #[lang="ty_desc"]
 #[derive(Copy)]
+#[cfg(stage0)] // SNAP 270a677
 pub struct TyDesc {
     // sizeof(T)
     pub size: usize,
@@ -197,8 +199,13 @@ extern "rust-intrinsic" {
     pub fn pref_align_of<T>() -> usize;
 
     /// Get a static pointer to a type descriptor.
+    #[cfg(stage0)] // SNAP 270a677
     pub fn get_tydesc<T: ?Sized>() -> *const TyDesc;
 
+    /// Gets a static string slice containing the name of a type.
+    #[cfg(not(stage0))] // SNAP 270a677
+    pub fn type_name<T: ?Sized>() -> &'static str;
+
     /// Gets an identifier which is globally unique to the specified type. This
     /// function will return the same value for a type regardless of whichever
     /// crate it is invoked in.

branches/snap-stage3/src/librustc/middle/lang_items.rs

@@ -316,9 +316,6 @@ lets_do_this! {
 
     StartFnLangItem,                 "start",                   start_fn;
 
-    TyDescStructLangItem,            "ty_desc",                 ty_desc;
-    OpaqueStructLangItem,            "opaque",                  opaque;
-
     EhPersonalityLangItem,           "eh_personality",          eh_personality;
 
     ExchangeHeapLangItem,            "exchange_heap",           exchange_heap;

branches/snap-stage3/src/librustc/middle/ty.rs

@@ -47,8 +47,7 @@ use middle::check_const;
 use middle::const_eval;
 use middle::def::{self, DefMap, ExportMap};
 use middle::dependency_format;
-use middle::lang_items::{FnTraitLangItem, FnMutTraitLangItem};
-use middle::lang_items::{FnOnceTraitLangItem, TyDescStructLangItem};
+use middle::lang_items::{FnTraitLangItem, FnMutTraitLangItem, FnOnceTraitLangItem};
 use middle::mem_categorization as mc;
 use middle::region;
 use middle::resolve_lifetime;
@@ -724,7 +723,6 @@ pub struct ctxt<'tcx> {
     pub object_cast_map: ObjectCastMap<'tcx>,
 
     pub map: ast_map::Map<'tcx>,
-    pub intrinsic_defs: RefCell<DefIdMap<Ty<'tcx>>>,
     pub freevars: RefCell<FreevarMap>,
     pub tcache: RefCell<DefIdMap<TypeScheme<'tcx>>>,
     pub rcache: RefCell<FnvHashMap<creader_cache_key, Ty<'tcx>>>,
@@ -2576,7 +2574,6 @@ pub fn mk_ctxt<'tcx>(s: Session,
         super_predicates: RefCell::new(DefIdMap()),
         object_cast_map: RefCell::new(NodeMap()),
         map: map,
-        intrinsic_defs: RefCell::new(DefIdMap()),
         freevars: freevars,
         tcache: RefCell::new(DefIdMap()),
         rcache: RefCell::new(FnvHashMap()),
@@ -5975,13 +5972,6 @@ pub fn required_region_bounds<'tcx>(tcx: &ctxt<'tcx>,
         .collect()
 }
 
-pub fn get_tydesc_ty<'tcx>(tcx: &ctxt<'tcx>) -> Result<Ty<'tcx>, String> {
-    tcx.lang_items.require(TyDescStructLangItem).map(|tydesc_lang_item| {
-        tcx.intrinsic_defs.borrow().get(&tydesc_lang_item).cloned()
-            .expect("Failed to resolve TyDesc")
-    })
-}
-
 pub fn item_variances(tcx: &ctxt, item_id: ast::DefId) -> Rc<ItemVariances> {
     lookup_locally_or_in_crate_store(
         "item_variance_map", item_id, &mut *tcx.item_variance_map.borrow_mut(),

branches/snap-stage3/src/librustc/util/ppaux.rs

@@ -1053,10 +1053,11 @@ impl<'tcx> Repr<'tcx> for ty::Variance {
 
 impl<'tcx> Repr<'tcx> for ty::Method<'tcx> {
     fn repr(&self, tcx: &ctxt<'tcx>) -> String {
-        format!("method(name: {}, generics: {}, fty: {}, \
+        format!("method(name: {}, generics: {}, predicates: {}, fty: {}, \
                  explicit_self: {}, vis: {}, def_id: {})",
                 self.name.repr(tcx),
                 self.generics.repr(tcx),
+                self.predicates.repr(tcx),
                 self.fty.repr(tcx),
                 self.explicit_self.repr(tcx),
                 self.vis.repr(tcx),

branches/snap-stage3/src/librustc_trans/trans/_match.rs

@@ -660,7 +660,7 @@ fn bind_subslice_pat(bcx: Block,
                      offset_right: uint) -> ValueRef {
     let _icx = push_ctxt("match::bind_subslice_pat");
     let vec_ty = node_id_type(bcx, pat_id);
-    let vt = tvec::vec_types(bcx, ty::sequence_element_type(bcx.tcx(), ty::type_content(vec_ty)));
+    let unit_ty = ty::sequence_element_type(bcx.tcx(), ty::type_content(vec_ty));
     let vec_datum = match_datum(val, vec_ty);
     let (base, len) = vec_datum.get_vec_base_and_len(bcx);
 
@@ -669,7 +669,7 @@ fn bind_subslice_pat(bcx: Block,
     let slice_len = Sub(bcx, len, slice_len_offset, DebugLoc::None);
     let slice_ty = ty::mk_slice(bcx.tcx(),
                                 bcx.tcx().mk_region(ty::ReStatic),
-                                ty::mt {ty: vt.unit_ty, mutbl: ast::MutImmutable});
+                                ty::mt {ty: unit_ty, mutbl: ast::MutImmutable});
     let scratch = rvalue_scratch_datum(bcx, slice_ty, "");
     Store(bcx, slice_begin,
           GEPi(bcx, scratch.val, &[0, abi::FAT_PTR_ADDR]));

branches/snap-stage3/src/librustc_trans/trans/base.rs

@@ -57,8 +57,7 @@ use trans::common::{C_null, C_struct_in_context, C_u64, C_u8, C_undef};
 use trans::common::{CrateContext, ExternMap, FunctionContext};
 use trans::common::{Result, NodeIdAndSpan};
 use trans::common::{node_id_type, return_type_is_void};
-use trans::common::{tydesc_info, type_is_immediate};
-use trans::common::{type_is_zero_size, val_ty};
+use trans::common::{type_is_immediate, type_is_zero_size, val_ty};
 use trans::common;
 use trans::consts;
 use trans::context::SharedCrateContext;
@@ -90,7 +89,6 @@ use std::ffi::{CStr, CString};
 use std::cell::{Cell, RefCell};
 use std::collections::HashSet;
 use std::mem;
-use std::rc::Rc;
 use std::str;
 use std::{i8, i16, i32, i64};
 use syntax::abi::{Rust, RustCall, RustIntrinsic, Abi};
@@ -392,22 +390,6 @@ pub fn malloc_raw_dyn<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
     Result::new(r.bcx, PointerCast(r.bcx, r.val, llty_ptr))
 }
 
-// Type descriptor and type glue stuff
-
-pub fn get_tydesc<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
-                            t: Ty<'tcx>) -> Rc<tydesc_info<'tcx>> {
-    match ccx.tydescs().borrow().get(&t) {
-        Some(inf) => return inf.clone(),
-        _ => { }
-    }
-
-    ccx.stats().n_static_tydescs.set(ccx.stats().n_static_tydescs.get() + 1);
-    let inf = Rc::new(glue::declare_tydesc(ccx, t));
-
-    ccx.tydescs().borrow_mut().insert(t, inf.clone());
-    inf
-}
-
 #[allow(dead_code)] // useful
 pub fn set_optimize_for_size(f: ValueRef) {
     llvm::SetFunctionAttribute(f, llvm::OptimizeForSizeAttribute)
@@ -702,6 +684,10 @@ pub fn iter_structural_ty<'blk, 'tcx, F>(cx: Block<'blk, 'tcx>,
         let unit_ty = ty::sequence_element_type(cx.tcx(), t);
         cx = tvec::iter_vec_raw(cx, base, unit_ty, len, f);
       }
+      ty::ty_vec(_, None) | ty::ty_str => {
+        let unit_ty = ty::sequence_element_type(cx.tcx(), t);
+        cx = tvec::iter_vec_raw(cx, data_ptr, unit_ty, info.unwrap(), f);
+      }
       ty::ty_tup(ref args) => {
           let repr = adt::represent_type(cx.ccx(), t);
           for (i, arg) in args.iter().enumerate() {
@@ -3133,7 +3119,6 @@ pub fn trans_crate<'tcx>(analysis: ty::CrateAnalysis<'tcx>)
     }
 
     for ccx in shared_ccx.iter() {
-        glue::emit_tydescs(&ccx);
         if ccx.sess().opts.debuginfo != NoDebugInfo {
             debuginfo::finalize(&ccx);
         }
@@ -3145,7 +3130,6 @@ pub fn trans_crate<'tcx>(analysis: ty::CrateAnalysis<'tcx>)
     if shared_ccx.sess().trans_stats() {
         let stats = shared_ccx.stats();
         println!("--- trans stats ---");
-        println!("n_static_tydescs: {}", stats.n_static_tydescs.get());
         println!("n_glues_created: {}", stats.n_glues_created.get());
         println!("n_null_glues: {}", stats.n_null_glues.get());
         println!("n_real_glues: {}", stats.n_real_glues.get());

branches/snap-stage3/src/librustc_trans/trans/common.rs

@@ -46,6 +46,7 @@ use arena::TypedArena;
 use libc::{c_uint, c_char};
 use std::ffi::CString;
 use std::cell::{Cell, RefCell};
+use std::result::Result as StdResult;
 use std::vec::Vec;
 use syntax::ast::Ident;
 use syntax::ast;
@@ -316,15 +317,6 @@ pub fn gensym_name(name: &str) -> PathElem {
     PathName(token::gensym(&format!("{}:{}", name, num)))
 }
 
-#[derive(Copy)]
-pub struct tydesc_info<'tcx> {
-    pub ty: Ty<'tcx>,
-    pub tydesc: ValueRef,
-    pub size: ValueRef,
-    pub align: ValueRef,
-    pub name: ValueRef,
-}
-
 /*
 * A note on nomenclature of linking: "extern", "foreign", and "upcall".
 *
@@ -1006,9 +998,9 @@ pub fn expr_ty_adjusted<'blk, 'tcx>(bcx: &BlockS<'blk, 'tcx>, ex: &ast::Expr) ->
 /// do not (necessarily) resolve all nested obligations on the impl. Note that type check should
 /// guarantee to us that all nested obligations *could be* resolved if we wanted to.
 pub fn fulfill_obligation<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
-                                span: Span,
-                                trait_ref: ty::PolyTraitRef<'tcx>)
-                                -> traits::Vtable<'tcx, ()>
+                                    span: Span,
+                                    trait_ref: ty::PolyTraitRef<'tcx>)
+                                    -> traits::Vtable<'tcx, ()>
 {
     let tcx = ccx.tcx();
 
@@ -1067,7 +1059,7 @@ pub fn fulfill_obligation<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
     let vtable = selection.map_move_nested(|predicate| {
         fulfill_cx.register_predicate_obligation(&infcx, predicate);
     });
-    let vtable = drain_fulfillment_cx(span, &infcx, &mut fulfill_cx, &vtable);
+    let vtable = drain_fulfillment_cx_or_panic(span, &infcx, &mut fulfill_cx, &vtable);
 
     info!("Cache miss: {}", trait_ref.repr(ccx.tcx()));
     ccx.trait_cache().borrow_mut().insert(trait_ref,
@@ -1076,6 +1068,22 @@ pub fn fulfill_obligation<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
     vtable
 }
 
+pub fn predicates_hold<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
+                                 predicates: Vec<ty::Predicate<'tcx>>)
+                                 -> bool
+{
+    debug!("predicates_hold(predicates={})",
+           predicates.repr(ccx.tcx()));
+
+    let infcx = infer::new_infer_ctxt(ccx.tcx());
+    let mut fulfill_cx = traits::FulfillmentContext::new();
+    for predicate in predicates {
+        let obligation = traits::Obligation::new(traits::ObligationCause::dummy(), predicate);
+        fulfill_cx.register_predicate_obligation(&infcx, obligation);
+    }
+    drain_fulfillment_cx(DUMMY_SP, &infcx, &mut fulfill_cx, &()).is_ok()
+}
+
 pub struct NormalizingClosureTyper<'a,'tcx:'a> {
     param_env: ty::ParameterEnvironment<'a, 'tcx>
 }
@@ -1123,11 +1131,36 @@ impl<'a,'tcx> ty::ClosureTyper<'tcx> for NormalizingClosureTyper<'a,'tcx> {
     }
 }
 
+pub fn drain_fulfillment_cx_or_panic<'a,'tcx,T>(span: Span,
+                                                infcx: &infer::InferCtxt<'a,'tcx>,
+                                                fulfill_cx: &mut traits::FulfillmentContext<'tcx>,
+                                                result: &T)
+                                                -> T
+    where T : TypeFoldable<'tcx> + Repr<'tcx>
+{
+    match drain_fulfillment_cx(span, infcx, fulfill_cx, result) {
+        Ok(v) => v,
+        Err(errors) => {
+            infcx.tcx.sess.span_bug(
+                span,
+                &format!("Encountered errors `{}` fulfilling during trans",
+                         errors.repr(infcx.tcx)));
+        }
+    }
+}
+
+/// Finishes processes any obligations that remain in the fulfillment
+/// context, and then "freshens" and returns `result`. This is
+/// primarily used during normalization and other cases where
+/// processing the obligations in `fulfill_cx` may cause type
+/// inference variables that appear in `result` to be unified, and
+/// hence we need to process those obligations to get the complete
+/// picture of the type.
 pub fn drain_fulfillment_cx<'a,'tcx,T>(span: Span,
-                                   infcx: &infer::InferCtxt<'a,'tcx>,
-                                   fulfill_cx: &mut traits::FulfillmentContext<'tcx>,
-                                   result: &T)
-                                   -> T
+                                       infcx: &infer::InferCtxt<'a,'tcx>,
+                                       fulfill_cx: &mut traits::FulfillmentContext<'tcx>,
+                                       result: &T)
+                                       -> StdResult<T,Vec<traits::FulfillmentError<'tcx>>>
     where T : TypeFoldable<'tcx> + Repr<'tcx>
 {
     debug!("drain_fulfillment_cx(result={})",
@@ -1140,16 +1173,13 @@ pub fn drain_fulfillment_cx<'a,'tcx,T>(span: Span,
     match fulfill_cx.select_all_or_error(infcx, &typer) {
         Ok(()) => { }
         Err(errors) => {
+            // We always want to surface any overflow errors, no matter what.
             if errors.iter().all(|e| e.is_overflow()) {
-                // See Ok(None) case above.
                 infcx.tcx.sess.span_fatal(
                     span,
                     "reached the recursion limit during monomorphization");
             } else {
-                infcx.tcx.sess.span_bug(
-                    span,
-                    &format!("Encountered errors `{}` fulfilling during trans",
-                            errors.repr(infcx.tcx)));
+                return Err(errors);
             }
         }
     }
@@ -1159,7 +1189,7 @@ pub fn drain_fulfillment_cx<'a,'tcx,T>(span: Span,
     // sort of overkill because we do not expect there to be any
     // unbound type variables, hence no `TyFresh` types should ever be
     // inserted.
-    result.fold_with(&mut infcx.freshener())
+    Ok(result.fold_with(&mut infcx.freshener()))
 }
 
 // Key used to lookup values supplied for type parameters in an expr.

branches/snap-stage3/src/librustc_trans/trans/consts.rs

@@ -317,7 +317,6 @@ pub fn const_expr<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
                     let info =
                         expr::unsized_info(
                             cx, k, e.id, ty, param_substs,
-                            |t| ty::mk_imm_rptr(cx.tcx(), cx.tcx().mk_region(ty::ReStatic), t),
                             || const_get_elt(cx, llconst, &[abi::FAT_PTR_EXTRA as u32]));
 
                     let unsized_ty = ty::unsize_ty(cx.tcx(), ty, k, e.span);