Revert "remove alias analysis and replace with borrowck"
18s perf regression compiling rustc with opts
This reverts commit 7f6ee0ce0d.
This commit is contained in:
Brian Anderson
parent
c058f1d992
commit
7ef825bb60
51 changed files with 1134 additions and 31 deletions
847
src/rustc/middle/alias.rs
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847
src/rustc/middle/alias.rs
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@ -0,0 +1,847 @@
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import syntax::{ast, ast_util, ast_map};
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import ast_util::path_to_ident;
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import ast::{ident, fn_ident, node_id};
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import syntax::codemap::span;
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import syntax::visit;
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import visit::vt;
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import std::list;
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import std::map::hashmap;
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import core::unreachable;
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import option::is_none;
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import list::list;
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import driver::session::session;
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import pat_util::*;
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import util::ppaux::ty_to_str;
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// This is not an alias-analyser (though it would merit from becoming one, or
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// getting input from one, to be more precise). It is a pass that checks
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// whether aliases are used in a safe way.
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enum copied { not_allowed, copied, not_copied, }
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enum invalid_reason { overwritten, val_taken, }
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type invalid = {reason: invalid_reason,
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node_id: node_id,
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sp: span, path: @ast::path};
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enum unsafe_ty { contains(ty::t), mutbl_contains(ty::t), }
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type binding = @{node_id: node_id,
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span: span,
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root_var: option<node_id>,
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local_id: uint,
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unsafe_tys: [unsafe_ty],
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mut copied: copied};
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// FIXME it may be worthwhile to use a linked list of bindings instead
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type scope = {bs: [binding],
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invalid: @mut @list<@invalid>};
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fn mk_binding(cx: ctx, id: node_id, span: span, root_var: option<node_id>,
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unsafe_tys: [unsafe_ty]) -> binding {
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alt root_var {
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some(r_id) { cx.ref_map.insert(id, r_id); }
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_ {}
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}
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ret @{node_id: id, span: span, root_var: root_var,
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local_id: local_id_of_node(cx, id),
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unsafe_tys: unsafe_tys,
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mut copied: not_copied};
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}
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enum local_info { local(uint), }
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type copy_map = std::map::hashmap<node_id, ()>;
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type ref_map = std::map::hashmap<node_id, node_id>;
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type ctx = {tcx: ty::ctxt,
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copy_map: copy_map,
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ref_map: ref_map,
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mut silent: bool};
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fn check_crate(tcx: ty::ctxt, crate: @ast::crate) -> (copy_map, ref_map) {
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// Stores information about function arguments that's otherwise not easily
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// available.
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let cx = @{tcx: tcx,
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copy_map: std::map::int_hash(),
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ref_map: std::map::int_hash(),
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mut silent: false};
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let v = @{visit_fn: bind visit_fn(cx, _, _, _, _, _, _, _),
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visit_expr: bind visit_expr(cx, _, _, _),
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visit_block: bind visit_block(cx, _, _, _)
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with *visit::default_visitor::<scope>()};
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let sc = {bs: [], invalid: @mut @list::nil};
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visit::visit_crate(*crate, sc, visit::mk_vt(v));
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tcx.sess.abort_if_errors();
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ret (cx.copy_map, cx.ref_map);
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}
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fn visit_fn(cx: @ctx, _fk: visit::fn_kind, decl: ast::fn_decl,
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body: ast::blk, _sp: span,
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id: ast::node_id, sc: scope, v: vt<scope>) {
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visit::visit_fn_decl(decl, sc, v);
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let fty = ty::node_id_to_type(cx.tcx, id);
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// Blocks need to obey any restrictions from the enclosing scope, and may
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// be called multiple times.
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let proto = ty::ty_fn_proto(fty);
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alt proto {
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ast::proto_block | ast::proto_any {
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check_loop(*cx, sc) {|| v.visit_block(body, sc, v);}
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}
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ast::proto_box | ast::proto_uniq | ast::proto_bare {
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let sc = {bs: [], invalid: @mut @list::nil};
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v.visit_block(body, sc, v);
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}
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}
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}
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fn visit_expr(cx: @ctx, ex: @ast::expr, sc: scope, v: vt<scope>) {
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let mut handled = true;
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alt ex.node {
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ast::expr_call(f, args, _) {
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check_call(cx, sc, f, args, v);
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visit_expr(cx, f, sc, v);
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}
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ast::expr_alt(input, arms, _) { check_alt(*cx, input, arms, sc, v); }
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ast::expr_path(pt) {
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check_var(*cx, ex, pt, ex.id, false, sc);
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handled = false;
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}
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ast::expr_swap(lhs, rhs) {
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check_lval(cx, lhs, sc, v);
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check_lval(cx, rhs, sc, v);
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handled = false;
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}
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ast::expr_move(dest, src) {
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visit_expr(cx, src, sc, v);
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check_lval(cx, dest, sc, v);
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check_lval(cx, src, sc, v);
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}
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ast::expr_assign(dest, src) | ast::expr_assign_op(_, dest, src) {
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visit_expr(cx, src, sc, v);
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check_lval(cx, dest, sc, v);
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}
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ast::expr_if(c, then, els) { check_if(c, then, els, sc, v); }
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ast::expr_while(_, _) {
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check_loop(*cx, sc) {|| visit::visit_expr(ex, sc, v); }
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}
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_ { handled = false; }
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}
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if !handled { visit::visit_expr(ex, sc, v); }
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}
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fn visit_block(cx: @ctx, b: ast::blk, sc: scope, v: vt<scope>) {
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let sc = sc;
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for b.node.stmts.each {|stmt|
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alt stmt.node {
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ast::stmt_decl(@{node: ast::decl_item(it), _}, _) {
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v.visit_item(it, sc, v);
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}
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ast::stmt_decl(@{node: ast::decl_local(locs), _}, _) {
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for locs.each {|loc|
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alt loc.node.init {
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some(init) {
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if init.op == ast::init_move {
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check_lval(cx, init.expr, sc, v);
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} else {
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visit_expr(cx, init.expr, sc, v);
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}
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}
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none { }
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}
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}
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}
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ast::stmt_expr(ex, _) | ast::stmt_semi(ex, _) {
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v.visit_expr(ex, sc, v);
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}
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}
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}
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visit::visit_expr_opt(b.node.expr, sc, v);
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}
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fn cant_copy(cx: ctx, b: binding) -> bool {
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if cx.tcx.sess.opts.borrowck == 2u {
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// borrowck is enabled. disable alias analysis.
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ret false;
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}
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alt b.copied {
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not_allowed { ret true; }
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copied { ret false; }
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not_copied {}
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}
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let ty = ty::node_id_to_type(cx.tcx, b.node_id);
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if ty::type_allows_implicit_copy(cx.tcx, ty) {
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b.copied = copied;
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cx.copy_map.insert(b.node_id, ());
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if copy_is_expensive(cx.tcx, ty) {
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cx.tcx.sess.span_warn(b.span,
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"inserting an implicit copy for type " +
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util::ppaux::ty_to_str(cx.tcx, ty));
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}
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ret false;
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} else { ret true; }
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}
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// FIXME this is a really awful hack
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fn local_id_for_args(cx: ctx, args: [@ast::expr]) -> uint {
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for vec::each(args) {|arg|
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alt arg.node {
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ast::expr_fn_block(decl, _, _) | ast::expr_fn(_, decl, _, _) |
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ast::expr_loop_body(@{node: ast::expr_fn_block(decl, _, _), _}) {
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if decl.inputs.len() > 0u {
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ret local_id_of_node(cx, decl.inputs[0].id);
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}
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}
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_ {}
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}
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}
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0xFFFFFFFFu
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}
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fn check_call(cx: @ctx, sc: scope, f: @ast::expr, args: [@ast::expr],
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v: vt<scope>) {
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let fty = ty::expr_ty(cx.tcx, f);
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let arg_ts = ty::ty_fn_args(fty);
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let mut mut_roots: [{arg: @ast::expr, node: node_id}] = [];
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let mut bindings = [];
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let mut blocks = [], loc_id = local_id_for_args(*cx, args);
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vec::iter2(args, arg_ts) {|arg, arg_t|
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let root = expr_root(*cx, arg, false);
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alt ty::resolved_mode(cx.tcx, arg_t.mode) {
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ast::by_mutbl_ref {
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alt path_def(*cx, arg) {
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some(def) {
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let dnum = ast_util::def_id_of_def(def).node;
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mut_roots += [{arg: arg, node: dnum}];
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}
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_ { }
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}
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}
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ast::by_ref | ast::by_val | ast::by_move | ast::by_copy {}
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}
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alt arg.node {
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ast::expr_fn_block(*) { blocks += [arg]; }
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ast::expr_loop_body(b) { blocks += [b]; }
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_ {
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let root_var = path_def_id(*cx, root.ex);
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let arg_copied = alt ty::resolved_mode(cx.tcx, arg_t.mode) {
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ast::by_move | ast::by_copy { copied }
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ast::by_mutbl_ref { not_allowed }
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ast::by_ref | ast::by_val { not_copied }
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};
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visit_expr(cx, arg, sc, v);
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bindings += [@{node_id: arg.id,
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span: arg.span,
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root_var: root_var,
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local_id: loc_id,
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unsafe_tys: unsafe_set(root.mutbl),
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mut copied: arg_copied}];
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}
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}
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}
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let f_may_close = alt f.node {
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ast::expr_path(_) { def_is_local_or_self(cx.tcx.def_map.get(f.id)) }
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_ { true }
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};
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if f_may_close {
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let mut i = 0u;
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for bindings.each {|b|
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let mut unsfe = vec::len(b.unsafe_tys) > 0u;
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alt b.root_var {
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some(rid) {
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for sc.bs.each {|o|
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if o.node_id == rid && vec::len(o.unsafe_tys) > 0u {
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unsfe = true; break;
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}
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}
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}
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_ {}
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}
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if unsfe && cant_copy(*cx, b) {
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err(*cx, f.span, #fmt["function may alias with argument \
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%u, which is not immutably rooted", i]);
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}
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i += 1u;
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}
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}
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let mut j = 0u;
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for bindings.each {|b|
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for b.unsafe_tys.each {|unsafe_ty|
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vec::iteri(arg_ts) {|i, arg_t|
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let mut_alias =
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(ast::by_mutbl_ref == ty::arg_mode(cx.tcx, arg_t));
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alt args[i].node {
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ast::expr_fn_block(*) | ast::expr_loop_body(_) {}
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_ {
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if i != j && ty_can_unsafely_include(
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*cx, unsafe_ty, arg_t.ty, mut_alias) &&
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cant_copy(*cx, b) {
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err(*cx, args[i].span,
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#fmt["argument %u may alias with argument %u, \
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which is not immutably rooted", i, j]);
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}
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}
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}
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}
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}
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j += 1u;
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}
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// Ensure we're not passing a root by mut alias.
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for mut_roots.each {|mroot|
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for bindings.each {|b|
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if b.node_id != mroot.arg.id {
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alt b.root_var {
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some(root) {
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if mroot.node == root && cant_copy(*cx, b) {
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err(*cx, mroot.arg.span,
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"passing a mut reference to a \
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variable that roots another reference");
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break;
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}
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}
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none { }
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}
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}
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}
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}
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// Check the bodies of block arguments against the current scope
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if blocks.len() > 0u {
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let inner_sc = {bs: bindings + sc.bs, invalid: sc.invalid};
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for blocks.each {|blk|
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alt check blk.node {
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ast::expr_fn_block(_, body, _) {
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v.visit_block(body, inner_sc, v);
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}
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}
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}
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for bindings.each {|binding|
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test_scope(*cx, sc, binding, none);
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}
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}
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}
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#[warn(no_non_implicitly_copyable_typarams)]
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fn check_alt(cx: ctx, input: @ast::expr, arms: [ast::arm], sc: scope,
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v: vt<scope>) {
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v.visit_expr(input, sc, v);
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let orig_invalid = *sc.invalid;
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let mut all_invalid = orig_invalid;
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let root = expr_root(cx, input, true);
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for arms.each {|a|
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let mut new_bs = sc.bs;
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let root_var = path_def_id(cx, root.ex);
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let pat_id_map = pat_util::pat_id_map(cx.tcx.def_map, a.pats[0]);
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type info = {
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id: node_id,
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mut unsafe_tys: [unsafe_ty],
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span: span};
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let mut binding_info: [info] = [];
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for a.pats.each {|pat|
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for pattern_roots(cx.tcx, root.mutbl, pat).each {|proot|
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let canon_id = pat_id_map.get(proot.name);
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alt vec::find(binding_info, {|x| x.id == canon_id}) {
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some(s) { s.unsafe_tys += unsafe_set(proot.mutbl); }
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none {
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binding_info += [
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{id: canon_id,
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mut unsafe_tys: unsafe_set(proot.mutbl),
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span: proot.span}];
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}
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}
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}
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}
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for binding_info.each {|info|
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new_bs += [mk_binding(cx, info.id, info.span, root_var,
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copy info.unsafe_tys)];
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};
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*sc.invalid = orig_invalid;
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visit::visit_arm(a, {bs: new_bs with sc}, v);
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all_invalid = join_invalid(all_invalid, *sc.invalid);
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};
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*sc.invalid = all_invalid;
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}
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fn check_for(cx: ctx, local: @ast::local, seq: @ast::expr, blk: ast::blk,
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sc: scope, v: vt<scope>) {
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let root = expr_root(cx, seq, false);
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// If this is a mut vector, don't allow it to be touched.
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let seq_t = ty::expr_ty(cx.tcx, seq);
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let mut cur_mutbl = root.mutbl;
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alt ty::get(seq_t).struct {
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ty::ty_vec(mt) {
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if mt.mutbl != ast::m_imm {
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cur_mutbl = some(contains(seq_t));
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}
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}
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_ {}
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}
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let root_var = path_def_id(cx, root.ex);
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let mut new_bs = sc.bs;
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for pattern_roots(cx.tcx, cur_mutbl, local.node.pat).each {|proot|
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new_bs += [mk_binding(cx, proot.id, proot.span, root_var,
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unsafe_set(proot.mutbl))];
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}
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visit::visit_block(blk, {bs: new_bs with sc}, v);
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}
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fn check_var(cx: ctx, ex: @ast::expr, p: @ast::path, id: ast::node_id,
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assign: bool, sc: scope) {
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let def = cx.tcx.def_map.get(id);
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if !def_is_local_or_self(def) { ret; }
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let my_defnum = ast_util::def_id_of_def(def).node;
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let my_local_id = local_id_of_node(cx, my_defnum);
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let var_t = ty::expr_ty(cx.tcx, ex);
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for sc.bs.each {|b|
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// excludes variables introduced since the alias was made
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if my_local_id < b.local_id {
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for b.unsafe_tys.each {|unsafe_ty|
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if ty_can_unsafely_include(cx, unsafe_ty, var_t, assign) {
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let inv = @{reason: val_taken, node_id: b.node_id,
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sp: ex.span, path: p};
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*sc.invalid = @list::cons(inv, *sc.invalid);
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}
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}
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} else if b.node_id == my_defnum {
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test_scope(cx, sc, b, some(p));
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}
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}
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}
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fn check_lval(cx: @ctx, dest: @ast::expr, sc: scope, v: vt<scope>) {
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alt dest.node {
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ast::expr_path(p) {
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let def = cx.tcx.def_map.get(dest.id);
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let dnum = ast_util::def_id_of_def(def).node;
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for sc.bs.each {|b|
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if b.root_var == some(dnum) {
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let inv = @{reason: overwritten, node_id: b.node_id,
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sp: dest.span, path: p};
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*sc.invalid = @list::cons(inv, *sc.invalid);
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}
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}
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}
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_ { visit_expr(cx, dest, sc, v); }
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}
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}
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fn check_if(c: @ast::expr, then: ast::blk, els: option<@ast::expr>,
|
||||
sc: scope, v: vt<scope>) {
|
||||
v.visit_expr(c, sc, v);
|
||||
let orig_invalid = *sc.invalid;
|
||||
v.visit_block(then, sc, v);
|
||||
let then_invalid = *sc.invalid;
|
||||
*sc.invalid = orig_invalid;
|
||||
visit::visit_expr_opt(els, sc, v);
|
||||
*sc.invalid = join_invalid(*sc.invalid, then_invalid);
|
||||
}
|
||||
|
||||
fn check_loop(cx: ctx, sc: scope, checker: fn()) {
|
||||
let orig_invalid = filter_invalid(*sc.invalid, sc.bs);
|
||||
checker();
|
||||
let new_invalid = filter_invalid(*sc.invalid, sc.bs);
|
||||
// Have to check contents of loop again if it invalidated an alias
|
||||
if list::len(orig_invalid) < list::len(new_invalid) {
|
||||
let old_silent = cx.silent;
|
||||
cx.silent = true;
|
||||
checker();
|
||||
cx.silent = old_silent;
|
||||
}
|
||||
*sc.invalid = new_invalid;
|
||||
}
|
||||
|
||||
fn test_scope(cx: ctx, sc: scope, b: binding, p: option<@ast::path>) {
|
||||
let mut prob = find_invalid(b.node_id, *sc.invalid);
|
||||
alt b.root_var {
|
||||
some(dn) {
|
||||
for sc.bs.each {|other|
|
||||
if !is_none(prob) { break; }
|
||||
if other.node_id == dn {
|
||||
prob = find_invalid(other.node_id, *sc.invalid);
|
||||
}
|
||||
}
|
||||
}
|
||||
_ {}
|
||||
}
|
||||
if !is_none(prob) && cant_copy(cx, b) {
|
||||
let i = option::get(prob);
|
||||
let msg = alt i.reason {
|
||||
overwritten { "overwriting " + ast_util::path_name(i.path) }
|
||||
val_taken { "taking the value of " + ast_util::path_name(i.path) }
|
||||
};
|
||||
let refname = alt p {
|
||||
some(pt) { "reference " + ast_util::path_name(pt) +
|
||||
", which is still used" }
|
||||
none { "an argument" }
|
||||
};
|
||||
err(cx, i.sp, msg + " will invalidate " + refname);
|
||||
}
|
||||
}
|
||||
|
||||
fn path_def(cx: ctx, ex: @ast::expr) -> option<ast::def> {
|
||||
ret alt ex.node {
|
||||
ast::expr_path(_) { some(cx.tcx.def_map.get(ex.id)) }
|
||||
_ { none }
|
||||
}
|
||||
}
|
||||
|
||||
fn path_def_id(cx: ctx, ex: @ast::expr) -> option<ast::node_id> {
|
||||
alt ex.node {
|
||||
ast::expr_path(_) {
|
||||
ret some(ast_util::def_id_of_def(cx.tcx.def_map.get(ex.id)).node);
|
||||
}
|
||||
_ { ret none; }
|
||||
}
|
||||
}
|
||||
|
||||
fn ty_can_unsafely_include(cx: ctx, needle: unsafe_ty, haystack: ty::t,
|
||||
mutbl: bool) -> bool {
|
||||
fn get_mutbl(cur: bool, mt: ty::mt) -> bool {
|
||||
ret cur || mt.mutbl != ast::m_imm;
|
||||
}
|
||||
fn helper(tcx: ty::ctxt, needle: unsafe_ty, haystack: ty::t, mutbl: bool)
|
||||
-> bool {
|
||||
if alt needle {
|
||||
contains(ty) { ty == haystack }
|
||||
mutbl_contains(ty) { mutbl && ty == haystack }
|
||||
} { ret true; }
|
||||
alt ty::get(haystack).struct {
|
||||
ty::ty_enum(_, ts) {
|
||||
for ts.tps.each {|t|
|
||||
if helper(tcx, needle, t, mutbl) { ret true; }
|
||||
}
|
||||
ret false;
|
||||
}
|
||||
ty::ty_box(mt) | ty::ty_ptr(mt) | ty::ty_uniq(mt) {
|
||||
ret helper(tcx, needle, mt.ty, get_mutbl(mutbl, mt));
|
||||
}
|
||||
ty::ty_rec(fields) {
|
||||
for fields.each {|f|
|
||||
if helper(tcx, needle, f.mt.ty, get_mutbl(mutbl, f.mt)) {
|
||||
ret true;
|
||||
}
|
||||
}
|
||||
ret false;
|
||||
}
|
||||
ty::ty_tup(ts) {
|
||||
for ts.each {|t| if helper(tcx, needle, t, mutbl) { ret true; } }
|
||||
ret false;
|
||||
}
|
||||
ty::ty_fn({proto: ast::proto_bare, _}) { ret false; }
|
||||
// These may contain anything.
|
||||
ty::ty_fn(_) | ty::ty_iface(_, _) { ret true; }
|
||||
// A type param may include everything, but can only be
|
||||
// treated as opaque downstream, and is thus safe unless we
|
||||
// saw mut fields, in which case the whole thing can be
|
||||
// overwritten.
|
||||
ty::ty_param(_, _) { ret mutbl; }
|
||||
_ { ret false; }
|
||||
}
|
||||
}
|
||||
ret helper(cx.tcx, needle, haystack, mutbl);
|
||||
}
|
||||
|
||||
fn def_is_local_or_self(d: ast::def) -> bool {
|
||||
alt d {
|
||||
ast::def_local(_, _) | ast::def_arg(_, _) | ast::def_binding(_) |
|
||||
ast::def_upvar(_, _, _) | ast::def_self(_) { true }
|
||||
_ { false }
|
||||
}
|
||||
}
|
||||
|
||||
fn local_id_of_node(cx: ctx, id: node_id) -> uint {
|
||||
alt cx.tcx.items.find(id) {
|
||||
some(ast_map::node_arg(_, id)) | some(ast_map::node_local(id)) { id }
|
||||
_ { 0u }
|
||||
}
|
||||
}
|
||||
|
||||
// Heuristic, somewhat random way to decide whether to warn when inserting an
|
||||
// implicit copy.
|
||||
fn copy_is_expensive(tcx: ty::ctxt, ty: ty::t) -> bool {
|
||||
fn score_ty(tcx: ty::ctxt, ty: ty::t) -> uint {
|
||||
ret alt ty::get(ty).struct {
|
||||
ty::ty_nil | ty::ty_bot | ty::ty_bool | ty::ty_int(_) |
|
||||
ty::ty_uint(_) | ty::ty_float(_) | ty::ty_type |
|
||||
ty::ty_ptr(_) { 1u }
|
||||
ty::ty_box(_) | ty::ty_iface(_, _) { 3u }
|
||||
ty::ty_constr(t, _) | ty::ty_res(_, t, _) { score_ty(tcx, t) }
|
||||
ty::ty_fn(_) { 4u }
|
||||
ty::ty_str | ty::ty_vec(_) | ty::ty_param(_, _) { 50u }
|
||||
ty::ty_uniq(mt) { 1u + score_ty(tcx, mt.ty) }
|
||||
ty::ty_enum(_, substs) {
|
||||
substs.tps.foldl(0u) { |sum, t| sum + score_ty(tcx, t) }
|
||||
}
|
||||
ty::ty_tup(ts) {
|
||||
ts.foldl(0u) { |sum, t| sum + score_ty(tcx, t) }
|
||||
}
|
||||
ty::ty_rec(fs) {
|
||||
let mut sum = 0u;
|
||||
for fs.each {|f| sum += score_ty(tcx, f.mt.ty); }
|
||||
sum
|
||||
}
|
||||
_ {
|
||||
tcx.sess.warn(#fmt("score_ty: unexpected type %s",
|
||||
ty_to_str(tcx, ty)));
|
||||
1u // ???
|
||||
}
|
||||
};
|
||||
}
|
||||
ret score_ty(tcx, ty) > 8u;
|
||||
}
|
||||
|
||||
type pattern_root = {id: node_id,
|
||||
name: ident,
|
||||
mutbl: option<unsafe_ty>,
|
||||
span: span};
|
||||
|
||||
fn pattern_roots(tcx: ty::ctxt, mutbl: option<unsafe_ty>, pat: @ast::pat)
|
||||
-> [pattern_root] {
|
||||
fn walk(tcx: ty::ctxt, mutbl: option<unsafe_ty>, pat: @ast::pat,
|
||||
&set: [pattern_root]) {
|
||||
alt pat.node {
|
||||
ast::pat_ident(nm, sub)
|
||||
if !pat_util::pat_is_variant(tcx.def_map, pat) {
|
||||
set += [{id: pat.id, name: path_to_ident(nm), mutbl: mutbl,
|
||||
span: pat.span}];
|
||||
option::iter(sub) {|p| walk(tcx, mutbl, p, set); };
|
||||
}
|
||||
ast::pat_wild | ast::pat_lit(_) | ast::pat_range(_, _) |
|
||||
ast::pat_ident(_, _) | ast::pat_enum(_, none) {}
|
||||
ast::pat_enum(_, some(ps)) | ast::pat_tup(ps) {
|
||||
for ps.each {|p| walk(tcx, mutbl, p, set); }
|
||||
}
|
||||
ast::pat_rec(fs, _) {
|
||||
let ty = ty::node_id_to_type(tcx, pat.id);
|
||||
for fs.each {|f|
|
||||
let m = ty::get_field(ty, f.ident).mt.mutbl != ast::m_imm,
|
||||
c = if m { some(contains(ty)) } else { mutbl };
|
||||
walk(tcx, c, f.pat, set);
|
||||
}
|
||||
}
|
||||
ast::pat_box(p) {
|
||||
let ty = ty::node_id_to_type(tcx, pat.id);
|
||||
let m = alt ty::get(ty).struct {
|
||||
ty::ty_box(mt) { mt.mutbl != ast::m_imm }
|
||||
_ { tcx.sess.span_bug(pat.span, "box pat has non-box type"); }
|
||||
},
|
||||
c = if m {some(contains(ty)) } else { mutbl };
|
||||
walk(tcx, c, p, set);
|
||||
}
|
||||
ast::pat_uniq(p) {
|
||||
let ty = ty::node_id_to_type(tcx, pat.id);
|
||||
let m = alt ty::get(ty).struct {
|
||||
ty::ty_uniq(mt) { mt.mutbl != ast::m_imm }
|
||||
_ { tcx.sess.span_bug(pat.span, "uniq pat has non-uniq type"); }
|
||||
},
|
||||
c = if m { some(contains(ty)) } else { mutbl };
|
||||
walk(tcx, c, p, set);
|
||||
}
|
||||
}
|
||||
}
|
||||
let mut set = [];
|
||||
walk(tcx, mutbl, pat, set);
|
||||
ret set;
|
||||
}
|
||||
|
||||
enum deref_t { unbox(bool), field, index, }
|
||||
|
||||
type deref = @{mutbl: bool, kind: deref_t, outer_t: ty::t};
|
||||
|
||||
fn expr_root(cx: ctx, ex: @ast::expr, autoderef: bool)
|
||||
-> {ex: @ast::expr, mutbl: option<unsafe_ty>} {
|
||||
|
||||
fn maybe_auto_unbox(tcx: ty::ctxt, t: ty::t) -> {t: ty::t, ds: [deref]} {
|
||||
let mut ds = [], t = t;
|
||||
loop {
|
||||
alt ty::get(t).struct {
|
||||
ty::ty_box(mt) | ty::ty_uniq(mt) | ty::ty_rptr(_, mt) {
|
||||
ds += [@{mutbl: mt.mutbl == ast::m_mutbl,
|
||||
kind: unbox(false),
|
||||
outer_t: t}];
|
||||
t = mt.ty;
|
||||
}
|
||||
ty::ty_res(_, inner, substs) {
|
||||
ds += [@{mutbl: false, kind: unbox(false), outer_t: t}];
|
||||
t = ty::subst(tcx, substs, inner);
|
||||
}
|
||||
ty::ty_enum(did, substs) {
|
||||
let variants = ty::enum_variants(tcx, did);
|
||||
if vec::len(*variants) != 1u ||
|
||||
vec::len(variants[0].args) != 1u {
|
||||
break;
|
||||
}
|
||||
ds += [@{mutbl: false, kind: unbox(false), outer_t: t}];
|
||||
t = ty::subst(tcx, substs, variants[0].args[0]);
|
||||
}
|
||||
_ { break; }
|
||||
}
|
||||
}
|
||||
ret {t: t, ds: ds};
|
||||
}
|
||||
|
||||
fn expr_root_(tcx: ty::ctxt, ctor_self: option<node_id>,
|
||||
ex: @ast::expr, autoderef: bool) -> {ex: @ast::expr,
|
||||
ds: @[deref]} {
|
||||
let mut ds: [deref] = [], ex = ex;
|
||||
loop {
|
||||
alt copy ex.node {
|
||||
ast::expr_field(base, ident, _) {
|
||||
let auto_unbox =
|
||||
maybe_auto_unbox(tcx, ty::expr_ty(tcx, base));
|
||||
let mut is_mutbl = false;
|
||||
alt ty::get(auto_unbox.t).struct {
|
||||
ty::ty_rec(fields) {
|
||||
for fields.each {|fld|
|
||||
if str::eq(ident, fld.ident) {
|
||||
is_mutbl = fld.mt.mutbl == ast::m_mutbl;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
ty::ty_class(did, _) {
|
||||
util::common::log_expr(*base);
|
||||
let in_self = alt ctor_self {
|
||||
some(selfid) {
|
||||
alt tcx.def_map.find(base.id) {
|
||||
some(ast::def_self(slfid)) { slfid == selfid }
|
||||
_ { false }
|
||||
}
|
||||
}
|
||||
none { false }
|
||||
};
|
||||
for ty::lookup_class_fields(tcx, did).each {|fld|
|
||||
if str::eq(ident, fld.ident) {
|
||||
is_mutbl = fld.mutability == ast::class_mutable
|
||||
|| in_self; // all fields can be mutated
|
||||
// in the ctor
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
_ {}
|
||||
}
|
||||
ds += [@{mutbl:is_mutbl, kind:field, outer_t:auto_unbox.t}];
|
||||
ds += auto_unbox.ds;
|
||||
ex = base;
|
||||
}
|
||||
ast::expr_index(base, _) {
|
||||
let auto_unbox =
|
||||
maybe_auto_unbox(tcx, ty::expr_ty(tcx, base));
|
||||
alt ty::get(auto_unbox.t).struct {
|
||||
ty::ty_evec(mt, _) |
|
||||
ty::ty_vec(mt) {
|
||||
ds +=
|
||||
[@{mutbl: mt.mutbl == ast::m_mutbl,
|
||||
kind: index,
|
||||
outer_t: auto_unbox.t}];
|
||||
}
|
||||
ty::ty_estr(_) |
|
||||
ty::ty_str {
|
||||
ds += [@{mutbl:false, kind:index, outer_t:auto_unbox.t}];
|
||||
}
|
||||
_ { break; }
|
||||
}
|
||||
ds += auto_unbox.ds;
|
||||
ex = base;
|
||||
}
|
||||
ast::expr_unary(op, base) {
|
||||
if op == ast::deref {
|
||||
let base_t = ty::expr_ty(tcx, base);
|
||||
let mut is_mutbl = false, ptr = false;
|
||||
alt ty::get(base_t).struct {
|
||||
ty::ty_box(mt) { is_mutbl = mt.mutbl==ast::m_mutbl; }
|
||||
ty::ty_uniq(mt) { is_mutbl = mt.mutbl==ast::m_mutbl; }
|
||||
ty::ty_res(_, _, _) { }
|
||||
ty::ty_enum(_, _) { }
|
||||
ty::ty_ptr(mt) | ty::ty_rptr(_, mt) {
|
||||
is_mutbl = mt.mutbl==ast::m_mutbl;
|
||||
ptr = true;
|
||||
}
|
||||
_ {
|
||||
tcx.sess.span_bug(
|
||||
base.span,
|
||||
"ill-typed base expression in deref"); }
|
||||
}
|
||||
ds += [@{mutbl: is_mutbl, kind: unbox(ptr && is_mutbl),
|
||||
outer_t: base_t}];
|
||||
ex = base;
|
||||
} else { break; }
|
||||
}
|
||||
_ { break; }
|
||||
}
|
||||
}
|
||||
if autoderef {
|
||||
let auto_unbox = maybe_auto_unbox(tcx, ty::expr_ty(tcx, ex));
|
||||
ds += auto_unbox.ds;
|
||||
}
|
||||
ret {ex: ex, ds: @ds};
|
||||
}
|
||||
|
||||
let base_root = expr_root_(cx.tcx, none, ex, autoderef);
|
||||
let mut unsafe_ty = none;
|
||||
for vec::each(*base_root.ds) {|d|
|
||||
if d.mutbl { unsafe_ty = some(contains(d.outer_t)); break; }
|
||||
}
|
||||
ret {ex: base_root.ex, mutbl: unsafe_ty};
|
||||
}
|
||||
|
||||
fn unsafe_set(from: option<unsafe_ty>) -> [unsafe_ty] {
|
||||
alt from { some(t) { [t] } _ { [] } }
|
||||
}
|
||||
|
||||
fn find_invalid(id: node_id, lst: @list<@invalid>) -> option<@invalid> {
|
||||
let mut cur = lst;
|
||||
loop {
|
||||
alt *cur {
|
||||
list::nil { ret none; }
|
||||
list::cons(head, tail) {
|
||||
if head.node_id == id { ret some(head); }
|
||||
cur = tail;
|
||||
}
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
fn join_invalid(a: @list<@invalid>, b: @list<@invalid>) -> @list<@invalid> {
|
||||
let mut result = a;
|
||||
list::iter(b) {|elt|
|
||||
let mut found = false;
|
||||
list::iter(a) {|e| if e == elt { found = true; } }
|
||||
if !found { result = @list::cons(elt, result); }
|
||||
}
|
||||
result
|
||||
}
|
||||
|
||||
fn filter_invalid(src: @list<@invalid>, bs: [binding]) -> @list<@invalid> {
|
||||
let mut out = @list::nil, cur = src;
|
||||
loop {
|
||||
alt *cur {
|
||||
list::cons(head, tail) {
|
||||
let p = vec::position(bs, {|b| b.node_id == head.node_id});
|
||||
if !is_none(p) { out = @list::cons(head, out); }
|
||||
cur = tail;
|
||||
}
|
||||
list::nil {
|
||||
ret out;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn err(cx: ctx, sp: span, err: str) {
|
||||
if !cx.silent || !cx.tcx.sess.has_errors() {
|
||||
cx.tcx.sess.span_err(sp, err);
|
||||
}
|
||||
}
|
||||
|
||||
// Local Variables:
|
||||
// mode: rust
|
||||
// fill-column: 78;
|
||||
// indent-tabs-mode: nil
|
||||
// c-basic-offset: 4
|
||||
// buffer-file-coding-system: utf-8-unix
|
||||
// End:
|
||||
|
|
@ -52,6 +52,7 @@ export decode_inlined_item;
|
|||
type maps = {
|
||||
mutbl_map: middle::borrowck::mutbl_map,
|
||||
root_map: middle::borrowck::root_map,
|
||||
copy_map: middle::alias::copy_map,
|
||||
last_use_map: middle::liveness::last_use_map,
|
||||
impl_map: middle::resolve::impl_map,
|
||||
method_map: middle::typeck::method_map,
|
||||
|
|
@ -830,6 +831,12 @@ fn encode_side_tables_for_id(ecx: @e::encode_ctxt,
|
|||
}
|
||||
}
|
||||
|
||||
option::iter(maps.copy_map.find(id)) {|_m|
|
||||
ebml_w.tag(c::tag_table_copy) {||
|
||||
ebml_w.id(id);
|
||||
}
|
||||
}
|
||||
|
||||
option::iter(maps.last_use_map.find(id)) {|m|
|
||||
ebml_w.tag(c::tag_table_last_use) {||
|
||||
ebml_w.id(id);
|
||||
|
|
@ -936,6 +943,8 @@ fn decode_side_tables(xcx: extended_decode_ctxt,
|
|||
|
||||
if tag == (c::tag_table_mutbl as uint) {
|
||||
dcx.maps.mutbl_map.insert(id, ());
|
||||
} else if tag == (c::tag_table_copy as uint) {
|
||||
dcx.maps.copy_map.insert(id, ());
|
||||
} else {
|
||||
let val_doc = entry_doc[c::tag_table_val];
|
||||
let val_dsr = ebml::ebml_deserializer(val_doc);
|
||||
|
|
|
|||
|
|
@ -171,12 +171,28 @@ export check_crate, root_map, mutbl_map;
|
|||
fn check_crate(tcx: ty::ctxt,
|
||||
method_map: typeck::method_map,
|
||||
crate: @ast::crate) -> (root_map, mutbl_map) {
|
||||
|
||||
// big hack to keep this off except when I want it on
|
||||
let msg_level = if tcx.sess.opts.borrowck != 0u {
|
||||
tcx.sess.opts.borrowck
|
||||
} else {
|
||||
os::getenv("RUST_BORROWCK").map_default(0u) { |v|
|
||||
option::get(uint::from_str(v))
|
||||
}
|
||||
};
|
||||
|
||||
let bccx = @{tcx: tcx,
|
||||
method_map: method_map,
|
||||
msg_level: msg_level,
|
||||
root_map: root_map(),
|
||||
mutbl_map: int_hash()};
|
||||
|
||||
let req_maps = gather_loans::gather_loans(bccx, crate);
|
||||
let req_maps = if msg_level > 0u {
|
||||
gather_loans::gather_loans(bccx, crate)
|
||||
} else {
|
||||
{req_loan_map: int_hash(),
|
||||
pure_map: int_hash()}
|
||||
};
|
||||
check_loans::check_loans(bccx, req_maps, crate);
|
||||
ret (bccx.root_map, bccx.mutbl_map);
|
||||
}
|
||||
|
|
@ -186,6 +202,7 @@ fn check_crate(tcx: ty::ctxt,
|
|||
|
||||
type borrowck_ctxt = @{tcx: ty::ctxt,
|
||||
method_map: typeck::method_map,
|
||||
msg_level: uint,
|
||||
root_map: root_map,
|
||||
mutbl_map: mutbl_map};
|
||||
|
||||
|
|
@ -346,7 +363,11 @@ impl error_methods for borrowck_ctxt {
|
|||
}
|
||||
|
||||
fn span_err(s: span, m: str) {
|
||||
self.tcx.sess.span_err(s, m);
|
||||
if self.msg_level == 1u {
|
||||
self.tcx.sess.span_warn(s, m);
|
||||
} else {
|
||||
self.tcx.sess.span_err(s, m);
|
||||
}
|
||||
}
|
||||
|
||||
fn span_note(s: span, m: str) {
|
||||
|
|
|
|||
|
|
@ -614,7 +614,25 @@ fn make_phi_bindings(bcx: block, map: [exit_node],
|
|||
bcx.fcx.lllocals.insert(node_id, local_mem(local));
|
||||
} else { success = false; }
|
||||
};
|
||||
if !success {
|
||||
if success {
|
||||
// Copy references that the alias analysis considered unsafe
|
||||
for ids.each_value {|node_id|
|
||||
if bcx.ccx().maps.copy_map.contains_key(node_id) {
|
||||
let local = alt bcx.fcx.lllocals.find(node_id) {
|
||||
some(local_mem(x)) { x }
|
||||
_ { bcx.tcx().sess.bug("someone \
|
||||
forgot to document an invariant in \
|
||||
make_phi_bindings"); }
|
||||
};
|
||||
let e_ty = node_id_type(bcx, node_id);
|
||||
let alloc = alloc_ty(bcx, e_ty);
|
||||
bcx = copy_val(bcx, INIT, alloc,
|
||||
load_if_immediate(bcx, local, e_ty), e_ty);
|
||||
add_clean(bcx, alloc, e_ty);
|
||||
bcx.fcx.lllocals.insert(node_id, local_mem(alloc));
|
||||
}
|
||||
};
|
||||
} else {
|
||||
Unreachable(bcx);
|
||||
}
|
||||
ret success;
|
||||
|
|
@ -701,7 +719,7 @@ fn bind_irrefutable_pat(bcx: block, pat: @ast::pat, val: ValueRef,
|
|||
alt pat.node {
|
||||
ast::pat_ident(_,inner) {
|
||||
if pat_is_variant(bcx.tcx().def_map, pat) { ret bcx; }
|
||||
if make_copy {
|
||||
if make_copy || ccx.maps.copy_map.contains_key(pat.id) {
|
||||
let ty = node_id_type(bcx, pat.id);
|
||||
let llty = type_of::type_of(ccx, ty);
|
||||
let alloc = alloca(bcx, llty);
|
||||
|
|
|
|||
|
|
@ -2888,11 +2888,22 @@ fn trans_arg_expr(cx: block, arg: ty::arg, lldestty: TypeRef, e: @ast::expr,
|
|||
// to have type lldestty (the callee's expected type).
|
||||
val = llvm::LLVMGetUndef(lldestty);
|
||||
} else if arg_mode == ast::by_ref || arg_mode == ast::by_val {
|
||||
let mut copied = false;
|
||||
let imm = ty::type_is_immediate(arg.ty);
|
||||
#debug[" arg.ty=%s, imm=%b, arg_mode=%?, lv.kind=%?",
|
||||
ty_to_str(bcx.tcx(), arg.ty), imm, arg_mode, lv.kind];
|
||||
if arg_mode == ast::by_ref && lv.kind != owned && imm {
|
||||
val = do_spill_noroot(bcx, val);
|
||||
copied = true;
|
||||
}
|
||||
if ccx.maps.copy_map.contains_key(e.id) && lv.kind != temporary {
|
||||
if !copied {
|
||||
let alloc = alloc_ty(bcx, arg.ty);
|
||||
bcx = copy_val(bcx, INIT, alloc,
|
||||
load_if_immediate(bcx, val, arg.ty), arg.ty);
|
||||
val = alloc;
|
||||
} else { bcx = take_ty(bcx, val, arg.ty); }
|
||||
add_clean(bcx, val, arg.ty);
|
||||
}
|
||||
if arg_mode == ast::by_val && (lv.kind == owned || !imm) {
|
||||
val = Load(bcx, val);
|
||||
|
|
|
|||
|
|
@ -19,13 +19,11 @@ enum reflector = {
|
|||
impl methods for reflector {
|
||||
|
||||
fn c_uint(u: uint) -> ValueRef {
|
||||
let bcx = self.bcx;
|
||||
C_uint(bcx.ccx(), u)
|
||||
C_uint(self.bcx.ccx(), u)
|
||||
}
|
||||
|
||||
fn visit(ty_name: str, args: [ValueRef]) {
|
||||
let bcx = self.bcx;
|
||||
let tcx = bcx.tcx();
|
||||
let tcx = self.bcx.tcx();
|
||||
let mth_idx = option::get(ty::method_idx("visit_" + ty_name,
|
||||
*self.visitor_methods));
|
||||
let mth_ty = ty::mk_fn(tcx, self.visitor_methods[mth_idx].fty);
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue