Back out copy-glue

This wasn't a good idea after all.

src/comp/back/abi.rs

@@ -52,7 +52,7 @@ const tydesc_field_align: int = 2;
 const tydesc_field_take_glue: int = 3;
 const tydesc_field_drop_glue: int = 4;
 const tydesc_field_free_glue: int = 5;
-const tydesc_field_copy_glue: int = 6;
+const tydesc_field_unused: int = 6;
 const tydesc_field_sever_glue: int = 7;
 const tydesc_field_mark_glue: int = 8;
 const tydesc_field_is_stateful: int = 9;

src/comp/middle/trans.rs

@@ -1122,7 +1122,6 @@ fn declare_tydesc(cx: &@local_ctxt, sp: &span, t: ty::t, ty_params: &[uint])
           mutable drop_glue: none::<ValueRef>,
           mutable free_glue: none::<ValueRef>,
           mutable cmp_glue: none::<ValueRef>,
-          mutable copy_glue: none::<ValueRef>,
           ty_params: ty_params};
     log "--- declare_tydesc " + ty_to_str(cx.ccx.tcx, t);
     ret info;
@@ -1216,7 +1215,6 @@ fn emit_tydescs(ccx: &@crate_ctxt) {
     for each pair: @{key: ty::t, val: @tydesc_info} in ccx.tydescs.items() {
         let glue_fn_ty = T_ptr(T_glue_fn(*ccx));
         let cmp_fn_ty = T_ptr(T_cmp_glue_fn(*ccx));
-        let copy_fn_ty = T_ptr(T_copy_glue_fn(*ccx));
         let ti = pair.val;
         let take_glue =
             alt { ti.take_glue } {
@@ -1238,11 +1236,6 @@ fn emit_tydescs(ccx: &@crate_ctxt) {
               none. { ccx.stats.n_null_glues += 1u; C_null(cmp_fn_ty) }
               some(v) { ccx.stats.n_real_glues += 1u; v }
             };
-        let copy_glue =
-            alt { ti.copy_glue } {
-              none. { ccx.stats.n_null_glues += 1u; C_null(copy_fn_ty) }
-              some(v) { ccx.stats.n_real_glues += 1u; v }
-            };
 
         let shape = shape::shape_of(ccx, pair.key);
         let shape_tables =
@@ -1257,7 +1250,7 @@ fn emit_tydescs(ccx: &@crate_ctxt) {
                             take_glue, // take_glue
                             drop_glue, // drop_glue
                             free_glue, // free_glue
-                            copy_glue, // copy_glue
+                            C_null(T_ptr(T_i8())), // unused
                             C_null(glue_fn_ty), // sever_glue
                             C_null(glue_fn_ty), // mark_glue
                             C_null(glue_fn_ty), // is_stateful
@@ -1274,14 +1267,6 @@ fn emit_tydescs(ccx: &@crate_ctxt) {
     }
 }
 
-// NOTE this is currently just a complicated way to do memmove. I'm working on
-// a representation of ivecs that will need pointers into itself, which must
-// be adjusted when copying. Will flesh this out when the time comes.
-fn make_copy_glue(cx: &@block_ctxt, src: ValueRef, dst: ValueRef, t: ty::t) {
-    let bcx = memmove_ty(cx, dst, src, t).bcx;
-    build_return(bcx);
-}
-
 fn make_take_glue(cx: &@block_ctxt, v: ValueRef, t: ty::t) {
     // NB: v is an *alias* of type t here, not a direct value.
 
@@ -2003,7 +1988,6 @@ fn lazily_emit_all_tydesc_glue(cx: &@block_ctxt,
     lazily_emit_tydesc_glue(cx, abi::tydesc_field_drop_glue, static_ti);
     lazily_emit_tydesc_glue(cx, abi::tydesc_field_free_glue, static_ti);
     lazily_emit_tydesc_glue(cx, abi::tydesc_field_cmp_glue, static_ti);
-    lazily_emit_tydesc_glue(cx, abi::tydesc_field_copy_glue, static_ti);
 }
 
 fn lazily_emit_all_generic_info_tydesc_glues(cx: &@block_ctxt,
@@ -2083,20 +2067,6 @@ fn lazily_emit_tydesc_glue(cx: &@block_ctxt, field: int,
                          ty_to_str(bcx_tcx(cx), ti.ty)];
               }
             }
-        } else if field == abi::tydesc_field_copy_glue {
-            alt { ti.copy_glue } {
-              some(_) {}
-              none. {
-                let lcx = cx.fcx.lcx;
-                let glue_fn =
-                    declare_generic_glue(lcx, ti.ty, T_copy_glue_fn(*lcx.ccx),
-                                         "copy");
-                ti.copy_glue = some(glue_fn);
-                make_generic_glue(lcx, cx.sp, ti.ty, glue_fn,
-                                  copy_helper(make_copy_glue),
-                                  ti.ty_params, "copy");
-              }
-            }
         }
       }
     }
@@ -2186,45 +2156,6 @@ fn call_cmp_glue(cx: &@block_ctxt, lhs: ValueRef, rhs: ValueRef, t: ty::t,
     ret rslt(r.bcx, bld::Load(r.bcx, llcmpresultptr));
 }
 
-fn call_copy_glue(cx: &@block_ctxt, dst: ValueRef, src: ValueRef, t: ty::t,
-                  take: bool) -> @block_ctxt {
-    // You can't call this on immediate types. Those are simply copied with
-    // Load/Store.
-    assert !type_is_immediate(bcx_ccx(cx), t);
-    let srcptr = bld::BitCast(cx, src, T_ptr(T_i8()));
-    let dstptr = bld::BitCast(cx, dst, T_ptr(T_i8()));
-    let ti = none;
-    let {bcx, val: lltydesc} = get_tydesc(cx, t, false, ti).result;
-    lazily_emit_tydesc_glue(cx, abi::tydesc_field_copy_glue, ti);
-    let lltydescs = bld::GEP
-        (bcx, lltydesc, [C_int(0), C_int(abi::tydesc_field_first_param)]);
-    lltydescs = bld::Load(bcx, lltydescs);
-
-    let llfn = alt ti {
-      none. {
-        bld::Load(bcx, bld::GEP
-            (bcx, lltydesc, [C_int(0), C_int(abi::tydesc_field_copy_glue)]))
-      }
-      some(sti) { option::get(sti.copy_glue) }
-    };
-    bld::Call(bcx, llfn, [C_null(T_ptr(T_nil())), bcx.fcx.lltaskptr,
-                          C_null(T_ptr(T_nil())), lltydescs, srcptr, dstptr]);
-    if take {
-        lazily_emit_tydesc_glue(cx, abi::tydesc_field_take_glue, ti);
-        llfn = alt ti {
-          none. {
-            bld::Load(bcx, bld::GEP(bcx, lltydesc,
-                                    [C_int(0),
-                                     C_int(abi::tydesc_field_take_glue)]))
-          }
-          some(sti) { option::get(sti.take_glue) }
-        };
-        bld::Call(bcx, llfn, [C_null(T_ptr(T_nil())), bcx.fcx.lltaskptr,
-                              C_null(T_ptr(T_nil())), lltydescs, dstptr]);
-    }
-    ret bcx;
-}
-
 
 // Compares two values. Performs the simple scalar comparison if the types are
 // scalar and calls to comparison glue otherwise.
@@ -2379,12 +2310,8 @@ fn copy_val_no_check(cx: &@block_ctxt, action: copy_action, dst: ValueRef,
         let bcx = if action == DROP_EXISTING {
             drop_ty(cx, dst, t).bcx
         } else { cx };
-        if ty::type_needs_copy_glue(ccx.tcx, t) {
-            ret call_copy_glue(bcx, dst, src, t, true);
-        } else {
-            bcx = memmove_ty(bcx, dst, src, t).bcx;
-            ret take_ty(bcx, dst, t).bcx;
-        }
+        bcx = memmove_ty(bcx, dst, src, t).bcx;
+        ret take_ty(bcx, dst, t).bcx;
     }
     ccx.sess.bug("unexpected type in trans::copy_val_no_check: " +
                      ty_to_str(ccx.tcx, t));
@@ -2421,11 +2348,7 @@ fn move_val(cx: @block_ctxt, action: copy_action, dst: ValueRef,
         ret cx;
     } else if type_is_structural_or_param(tcx, t) {
         if action == DROP_EXISTING { cx = drop_ty(cx, dst, t).bcx; }
-        if ty::type_needs_copy_glue(tcx, t) {
-            cx = call_copy_glue(cx, dst, src_val, t, false);
-        } else {
-            cx = memmove_ty(cx, dst, src_val, t).bcx;
-        }
+        cx = memmove_ty(cx, dst, src_val, t).bcx;
         if src.is_mem {
             ret zero_alloca(cx, src_val, t).bcx;
         } else { // Temporary value

src/comp/middle/trans_common.rs

@@ -85,7 +85,6 @@ type tydesc_info =
      mutable drop_glue: option::t<ValueRef>,
      mutable free_glue: option::t<ValueRef>,
      mutable cmp_glue: option::t<ValueRef>,
-     mutable copy_glue: option::t<ValueRef>,
      ty_params: [uint]};
 
 /*
@@ -615,14 +614,6 @@ fn T_cmp_glue_fn(cx: &crate_ctxt) -> TypeRef {
     ret t;
 }
 
-fn T_copy_glue_fn(cx: &crate_ctxt) -> TypeRef {
-    let s = "copy_glue_fn";
-    if cx.tn.name_has_type(s) { ret cx.tn.get_type(s); }
-    let t = T_tydesc_field(cx, abi::tydesc_field_copy_glue);
-    cx.tn.associate(s, t);
-    ret t;
-}
-
 fn T_tydesc(taskptr_type: TypeRef) -> TypeRef {
     let tydesc = T_named_struct("tydesc");
     let tydescpp = T_ptr(T_ptr(tydesc));
@@ -633,13 +624,10 @@ fn T_tydesc(taskptr_type: TypeRef) -> TypeRef {
     let cmp_glue_fn_ty =
         T_ptr(T_fn([T_ptr(T_i1()), taskptr_type, T_ptr(tydesc), tydescpp,
                     pvoid, pvoid, T_i8()], T_void()));
-    let copy_glue_fn_ty =
-        T_ptr(T_fn([T_ptr(T_nil()), taskptr_type, T_ptr(T_nil()), tydescpp,
-                    pvoid, pvoid], T_void()));
 
     let elems =
         [tydescpp, T_int(), T_int(), glue_fn_ty, glue_fn_ty, glue_fn_ty,
-         copy_glue_fn_ty, glue_fn_ty, glue_fn_ty, glue_fn_ty, cmp_glue_fn_ty,
+         T_ptr(T_i8()), glue_fn_ty, glue_fn_ty, glue_fn_ty, cmp_glue_fn_ty,
          T_ptr(T_i8()), T_ptr(T_i8()), T_int()];
     set_struct_body(tydesc, elems);
     ret tydesc;

src/comp/middle/trans_ivec.rs

@@ -367,7 +367,6 @@ fn trans_append(cx: &@block_ctxt, t: ty::t, lhs: ValueRef,
     lazily_emit_tydesc_glue(bcx, abi::tydesc_field_take_glue, none);
     lazily_emit_tydesc_glue(bcx, abi::tydesc_field_drop_glue, none);
     lazily_emit_tydesc_glue(bcx, abi::tydesc_field_free_glue, none);
-    lazily_emit_tydesc_glue(bcx, abi::tydesc_field_copy_glue, none);
     let rhs_len_and_data = get_len_and_data(bcx, rhs, unit_ty);
     let rhs_len = rhs_len_and_data.len;
     let rhs_data = rhs_len_and_data.data;

src/comp/middle/ty.rs

@@ -156,7 +156,6 @@ export type_kind;
 export type_err;
 export type_err_to_str;
 export type_has_dynamic_size;
-export type_needs_copy_glue;
 export type_has_pointers;
 export type_needs_drop;
 export type_is_bool;
@@ -1178,17 +1177,6 @@ fn type_has_dynamic_size(cx: &ctxt, ty: t) -> bool {
     });
 }
 
-fn type_needs_copy_glue(cx: &ctxt, ty: t) -> bool {
-    ret type_structurally_contains(cx, ty, fn(sty: &sty) -> bool {
-        ret alt sty {
-          ty_param(_, _) { true }
-          ty_vec(_) { true }
-          ty_istr. { true }
-          _ { false }
-        };
-    });
-}
-
 fn type_is_integral(cx: &ctxt, ty: t) -> bool {
     alt struct(cx, ty) {
       ty_int. { ret true; }

src/rt/rust_internal.h

@@ -257,8 +257,6 @@ struct rust_timer {
 
 typedef void CDECL (glue_fn)(void *, rust_task *, void *,
                              const type_desc **, void *);
-typedef void CDECL (copy_glue_fn)(void *, rust_task *, void *,
-                                  const type_desc **, void *, void *);
 typedef void CDECL (cmp_glue_fn)(void *, rust_task *, void *,
                                  const type_desc **,
                                  void *, void *, int8_t);
@@ -277,7 +275,7 @@ struct type_desc {
     glue_fn *take_glue;
     glue_fn *drop_glue;
     glue_fn *free_glue;
-    copy_glue_fn *copy_glue;
+    void *unused;
     glue_fn *sever_glue;    // For GC.
     glue_fn *mark_glue;     // For GC.
     uintptr_t is_stateful;