782 lines
26 KiB
Rust
782 lines
26 KiB
Rust
import driver::session::session;
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import lib::llvm::llvm;
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import lib::llvm::{ValueRef, BasicBlockRef};
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import pat_util::*;
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import build::*;
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import base::*;
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import syntax::ast;
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import syntax::ast_util;
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import syntax::ast_util::{dummy_sp, path_to_ident};
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import syntax::ast::def_id;
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import syntax::codemap::span;
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import syntax::print::pprust::pat_to_str;
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import middle::resolve3::DefMap;
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import back::abi;
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import std::map::hashmap;
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import dvec::{dvec, extensions};
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import common::*;
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// An option identifying a branch (either a literal, a enum variant or a
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// range)
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enum opt {
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lit(@ast::expr),
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var(/* disr val */int, /* variant dids */{enm: def_id, var: def_id}),
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range(@ast::expr, @ast::expr)
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}
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fn opt_eq(tcx: ty::ctxt, a: opt, b: opt) -> bool {
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alt (a, b) {
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(lit(a), lit(b)) { const_eval::compare_lit_exprs(tcx, a, b) == 0 }
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(range(a1, a2), range(b1, b2)) {
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const_eval::compare_lit_exprs(tcx, a1, b1) == 0 &&
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const_eval::compare_lit_exprs(tcx, a2, b2) == 0
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}
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(var(a, _), var(b, _)) { a == b }
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_ { false }
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}
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}
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enum opt_result {
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single_result(result),
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range_result(result, result),
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}
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fn trans_opt(bcx: block, o: opt) -> opt_result {
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let _icx = bcx.insn_ctxt(~"alt::trans_opt");
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let ccx = bcx.ccx();
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let mut bcx = bcx;
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alt o {
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lit(l) {
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alt l.node {
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ast::expr_vstore(@{node: ast::expr_lit(
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@{node: ast::lit_str(s), _}), _},
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ast::vstore_uniq) {
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let strty = ty::mk_estr(bcx.tcx(), ty::vstore_uniq);
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let cell = empty_dest_cell();
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bcx = tvec::trans_estr(bcx, s, ast::vstore_uniq, by_val(cell));
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add_clean_temp(bcx, *cell, strty);
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ret single_result(rslt(bcx, *cell));
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}
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_ {
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ret single_result(
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rslt(bcx, trans_const_expr(ccx, l)));
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}
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}
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}
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var(disr_val, _) { ret single_result(rslt(bcx, C_int(ccx, disr_val))); }
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range(l1, l2) {
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ret range_result(rslt(bcx, trans_const_expr(ccx, l1)),
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rslt(bcx, trans_const_expr(ccx, l2)));
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}
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}
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}
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fn variant_opt(tcx: ty::ctxt, pat_id: ast::node_id) -> opt {
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let vdef = ast_util::variant_def_ids(tcx.def_map.get(pat_id));
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let variants = ty::enum_variants(tcx, vdef.enm);
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for vec::each(*variants) |v| {
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if vdef.var == v.id { ret var(v.disr_val, vdef); }
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}
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core::unreachable();
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}
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type bind_map = ~[{ident: ast::ident, val: ValueRef}];
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fn assoc(key: ast::ident, list: bind_map) -> option<ValueRef> {
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for vec::each(list) |elt| {
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if str::eq(*elt.ident, *key) { ret some(elt.val); }
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}
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ret none;
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}
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type match_branch =
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@{pats: ~[@ast::pat],
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bound: bind_map,
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data: @{bodycx: block,
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guard: option<@ast::expr>,
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id_map: pat_id_map}};
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type match = ~[match_branch];
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fn has_nested_bindings(m: match, col: uint) -> bool {
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for vec::each(m) |br| {
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alt br.pats[col].node {
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ast::pat_ident(_, some(_)) { ret true; }
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_ {}
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}
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}
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ret false;
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}
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fn expand_nested_bindings(m: match, col: uint, val: ValueRef) -> match {
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let mut result = ~[];
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for vec::each(m) |br| {
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alt br.pats[col].node {
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ast::pat_ident(name, some(inner)) {
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let pats = vec::append(
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vec::slice(br.pats, 0u, col),
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vec::append(~[inner],
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// FIXME (#2880): use view here.
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vec::slice(br.pats, col + 1u, br.pats.len())));
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vec::push(result,
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@{pats: pats,
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bound: vec::append(
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br.bound, ~[{ident: path_to_ident(name),
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val: val}])
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with *br});
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}
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_ { vec::push(result, br); }
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}
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}
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result
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}
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type enter_pat = fn(@ast::pat) -> option<~[@ast::pat]>;
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fn enter_match(dm: DefMap, m: match, col: uint, val: ValueRef,
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e: enter_pat) -> match {
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let mut result = ~[];
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for vec::each(m) |br| {
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alt e(br.pats[col]) {
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some(sub) {
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let pats = vec::append(
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// FIXME (#2880): use view here.
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vec::append(sub, vec::slice(br.pats, 0u, col)),
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// FIXME (#2880): use view here.
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vec::slice(br.pats, col + 1u, br.pats.len()));
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let self = br.pats[col];
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let bound = alt self.node {
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ast::pat_ident(name, none) if !pat_is_variant(dm, self) {
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vec::append(br.bound,
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~[{ident: path_to_ident(name), val: val}])
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}
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_ { br.bound }
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};
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vec::push(result, @{pats: pats, bound: bound with *br});
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}
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none { }
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}
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}
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ret result;
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}
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fn enter_default(dm: DefMap, m: match, col: uint, val: ValueRef) -> match {
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do enter_match(dm, m, col, val) |p| {
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alt p.node {
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ast::pat_wild | ast::pat_rec(_, _) | ast::pat_tup(_) { some(~[]) }
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ast::pat_ident(_, none) if !pat_is_variant(dm, p) {
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some(~[])
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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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fn enter_opt(tcx: ty::ctxt, m: match, opt: opt, col: uint,
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variant_size: uint, val: ValueRef) -> match {
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let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
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do enter_match(tcx.def_map, m, col, val) |p| {
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alt p.node {
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ast::pat_enum(_, subpats) {
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if opt_eq(tcx, variant_opt(tcx, p.id), opt) {
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some(option::get_default(subpats,
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vec::from_elem(variant_size, dummy))) }
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else { none }
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}
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ast::pat_ident(_, none) if pat_is_variant(tcx.def_map, p) {
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if opt_eq(tcx, variant_opt(tcx, p.id), opt) { some(~[]) }
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else { none }
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}
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ast::pat_lit(l) {
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if opt_eq(tcx, lit(l), opt) { some(~[]) } else { none }
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}
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ast::pat_range(l1, l2) {
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if opt_eq(tcx, range(l1, l2), opt) { some(~[]) } else { none }
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}
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_ { some(vec::from_elem(variant_size, dummy)) }
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}
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}
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}
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fn enter_rec(dm: DefMap, m: match, col: uint, fields: ~[ast::ident],
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val: ValueRef) -> match {
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let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
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do enter_match(dm, m, col, val) |p| {
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alt p.node {
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ast::pat_rec(fpats, _) {
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let mut pats = ~[];
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for vec::each(fields) |fname| {
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let mut pat = dummy;
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for vec::each(fpats) |fpat| {
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if str::eq(*fpat.ident, *fname) { pat = fpat.pat; break; }
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}
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vec::push(pats, pat);
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}
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some(pats)
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}
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_ { some(vec::from_elem(fields.len(), dummy)) }
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}
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}
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}
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fn enter_tup(dm: DefMap, m: match, col: uint, val: ValueRef,
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n_elts: uint) -> match {
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let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
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do enter_match(dm, m, col, val) |p| {
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alt p.node {
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ast::pat_tup(elts) { some(elts) }
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_ { some(vec::from_elem(n_elts, dummy)) }
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}
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}
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}
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fn enter_box(dm: DefMap, m: match, col: uint, val: ValueRef) -> match {
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let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
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do enter_match(dm, m, col, val) |p| {
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alt p.node {
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ast::pat_box(sub) { some(~[sub]) }
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_ { some(~[dummy]) }
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}
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}
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}
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fn enter_uniq(dm: DefMap, m: match, col: uint, val: ValueRef) -> match {
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let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
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do enter_match(dm, m, col, val) |p| {
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alt p.node {
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ast::pat_uniq(sub) { some(~[sub]) }
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_ { some(~[dummy]) }
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}
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}
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}
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fn get_options(ccx: @crate_ctxt, m: match, col: uint) -> ~[opt] {
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fn add_to_set(tcx: ty::ctxt, &&set: dvec<opt>, val: opt) {
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if set.any(|l| opt_eq(tcx, l, val)) {ret;}
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set.push(val);
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}
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let found = dvec();
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for vec::each(m) |br| {
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let cur = br.pats[col];
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if pat_is_variant(ccx.tcx.def_map, cur) {
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add_to_set(ccx.tcx, found, variant_opt(ccx.tcx, br.pats[col].id));
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} else {
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alt cur.node {
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ast::pat_lit(l) { add_to_set(ccx.tcx, found, lit(l)); }
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ast::pat_range(l1, l2) {
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add_to_set(ccx.tcx, found, range(l1, l2));
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}
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_ {}
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}
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}
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}
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ret vec::from_mut(dvec::unwrap(found));
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}
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fn extract_variant_args(bcx: block, pat_id: ast::node_id,
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vdefs: {enm: def_id, var: def_id}, val: ValueRef) ->
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{vals: ~[ValueRef], bcx: block} {
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let _icx = bcx.insn_ctxt(~"alt::extract_variant_args");
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let ccx = bcx.fcx.ccx;
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let enum_ty_substs = alt check ty::get(node_id_type(bcx, pat_id)).struct {
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ty::ty_enum(id, substs) { assert id == vdefs.enm; substs.tps }
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};
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let mut blobptr = val;
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let variants = ty::enum_variants(ccx.tcx, vdefs.enm);
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let size = ty::enum_variant_with_id(ccx.tcx, vdefs.enm,
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vdefs.var).args.len();
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if size > 0u && (*variants).len() != 1u {
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let enumptr =
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PointerCast(bcx, val, T_opaque_enum_ptr(ccx));
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blobptr = GEPi(bcx, enumptr, ~[0u, 1u]);
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}
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let vdefs_tg = vdefs.enm;
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let vdefs_var = vdefs.var;
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let args = do vec::from_fn(size) |i| {
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GEP_enum(bcx, blobptr, vdefs_tg, vdefs_var,
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enum_ty_substs, i)
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};
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ret {vals: args, bcx: bcx};
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}
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fn collect_record_fields(m: match, col: uint) -> ~[ast::ident] {
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let mut fields: ~[ast::ident] = ~[];
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for vec::each(m) |br| {
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alt br.pats[col].node {
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ast::pat_rec(fs, _) {
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for vec::each(fs) |f| {
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if !vec::any(fields, |x| str::eq(*f.ident, *x)) {
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vec::push(fields, f.ident);
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}
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}
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}
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_ { }
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}
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}
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ret fields;
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}
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fn root_pats_as_necessary(bcx: block, m: match, col: uint, val: ValueRef) {
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for vec::each(m) |br| {
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let pat_id = br.pats[col].id;
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alt bcx.ccx().maps.root_map.find({id:pat_id, derefs:0u}) {
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none {}
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some(scope_id) {
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// Note: the scope_id will always be the id of the alt. See the
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// extended comment in rustc::middle::borrowck::preserve() for
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// details (look for the case covering cat_discr).
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let ty = node_id_type(bcx, pat_id);
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let val = load_if_immediate(bcx, val, ty);
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root_value(bcx, val, ty, scope_id);
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ret; // if we kept going, we'd only be rooting same value again
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}
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}
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}
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}
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fn any_box_pat(m: match, col: uint) -> bool {
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for vec::each(m) |br| {
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alt br.pats[col].node { ast::pat_box(_) { ret true; } _ { } }
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}
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ret false;
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}
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fn any_uniq_pat(m: match, col: uint) -> bool {
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for vec::each(m) |br| {
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alt br.pats[col].node { ast::pat_uniq(_) { ret true; } _ { } }
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}
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ret false;
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}
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fn any_tup_pat(m: match, col: uint) -> bool {
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for vec::each(m) |br| {
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alt br.pats[col].node { ast::pat_tup(_) { ret true; } _ { } }
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}
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ret false;
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}
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type exit_node = {bound: bind_map, from: BasicBlockRef, to: BasicBlockRef};
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type mk_fail = fn@() -> BasicBlockRef;
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fn pick_col(m: match) -> uint {
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fn score(p: @ast::pat) -> uint {
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alt p.node {
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ast::pat_lit(_) | ast::pat_enum(_, _) | ast::pat_range(_, _) { 1u }
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ast::pat_ident(_, some(p)) { score(p) }
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_ { 0u }
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}
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}
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let scores = vec::to_mut(vec::from_elem(m[0].pats.len(), 0u));
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for vec::each(m) |br| {
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let mut i = 0u;
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for vec::each(br.pats) |p| { scores[i] += score(p); i += 1u; }
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}
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let mut max_score = 0u;
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let mut best_col = 0u;
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let mut i = 0u;
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for vec::each(scores) |score| {
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// Irrefutable columns always go first, they'd only be duplicated in
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// the branches.
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if score == 0u { ret i; }
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// If no irrefutable ones are found, we pick the one with the biggest
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// branching factor.
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if score > max_score { max_score = score; best_col = i; }
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i += 1u;
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}
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ret best_col;
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}
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fn compile_submatch(bcx: block, m: match, vals: ~[ValueRef],
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chk: option<mk_fail>, &exits: ~[exit_node]) {
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let _icx = bcx.insn_ctxt(~"alt::compile_submatch");
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let mut bcx = bcx;
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let tcx = bcx.tcx(), dm = tcx.def_map;
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if m.len() == 0u { Br(bcx, option::get(chk)()); ret; }
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if m[0].pats.len() == 0u {
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let data = m[0].data;
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alt data.guard {
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some(e) {
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// Temporarily set bindings. They'll be rewritten to PHI nodes
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// for the actual arm block.
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for data.id_map.each |key, val| {
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let loc = local_mem(option::get(assoc(key, m[0].bound)));
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bcx.fcx.lllocals.insert(val, loc);
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};
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let {bcx: guard_cx, val} = {
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do with_scope_result(bcx, e.info(), ~"guard") |bcx| {
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trans_temp_expr(bcx, e)
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}
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};
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bcx = do with_cond(guard_cx, Not(guard_cx, val)) |bcx| {
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compile_submatch(bcx, vec::tail(m), vals, chk, exits);
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bcx
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};
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}
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_ { }
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}
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if !bcx.unreachable {
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vec::push(exits, {bound: m[0].bound, from: bcx.llbb,
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to: data.bodycx.llbb});
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}
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Br(bcx, data.bodycx.llbb);
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ret;
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}
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let col = pick_col(m);
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let val = vals[col];
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let m = if has_nested_bindings(m, col) {
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expand_nested_bindings(m, col, val)
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} else { m };
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let vals_left = vec::append(vec::slice(vals, 0u, col),
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// FIXME (#2880): use view here.
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vec::slice(vals, col + 1u, vals.len()));
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let ccx = bcx.fcx.ccx;
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let mut pat_id = 0;
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for vec::each(m) |br| {
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// Find a real id (we're adding placeholder wildcard patterns, but
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// each column is guaranteed to have at least one real pattern)
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if pat_id == 0 { pat_id = br.pats[col].id; }
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}
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root_pats_as_necessary(bcx, m, col, val);
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let rec_fields = collect_record_fields(m, col);
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// Separate path for extracting and binding record fields
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if rec_fields.len() > 0u {
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let fields = ty::get_fields(node_id_type(bcx, pat_id));
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let mut rec_vals = ~[];
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for vec::each(rec_fields) |field_name| {
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let ix = option::get(ty::field_idx(field_name, fields));
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vec::push(rec_vals, GEPi(bcx, val, ~[0u, ix]));
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}
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compile_submatch(bcx, enter_rec(dm, m, col, rec_fields, val),
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vec::append(rec_vals, vals_left), chk, exits);
|
|
ret;
|
|
}
|
|
|
|
if any_tup_pat(m, col) {
|
|
let tup_ty = node_id_type(bcx, pat_id);
|
|
let n_tup_elts = alt ty::get(tup_ty).struct {
|
|
ty::ty_tup(elts) { elts.len() }
|
|
_ { ccx.sess.bug(~"non-tuple type in tuple pattern"); }
|
|
};
|
|
let mut tup_vals = ~[], i = 0u;
|
|
while i < n_tup_elts {
|
|
vec::push(tup_vals, GEPi(bcx, val, ~[0u, i]));
|
|
i += 1u;
|
|
}
|
|
compile_submatch(bcx, enter_tup(dm, m, col, val, n_tup_elts),
|
|
vec::append(tup_vals, vals_left), chk, exits);
|
|
ret;
|
|
}
|
|
|
|
// Unbox in case of a box field
|
|
if any_box_pat(m, col) {
|
|
let llbox = Load(bcx, val);
|
|
let box_no_addrspace = non_gc_box_cast(bcx, llbox);
|
|
let unboxed =
|
|
GEPi(bcx, box_no_addrspace, ~[0u, abi::box_field_body]);
|
|
compile_submatch(bcx, enter_box(dm, m, col, val),
|
|
vec::append(~[unboxed], vals_left), chk, exits);
|
|
ret;
|
|
}
|
|
|
|
if any_uniq_pat(m, col) {
|
|
let llbox = Load(bcx, val);
|
|
let box_no_addrspace = non_gc_box_cast(bcx, llbox);
|
|
let unboxed =
|
|
GEPi(bcx, box_no_addrspace, ~[0u, abi::box_field_body]);
|
|
compile_submatch(bcx, enter_uniq(dm, m, col, val),
|
|
vec::append(~[unboxed], vals_left), chk, exits);
|
|
ret;
|
|
}
|
|
|
|
// Decide what kind of branch we need
|
|
let opts = get_options(ccx, m, col);
|
|
enum branch_kind { no_branch, single, switch, compare, }
|
|
let mut kind = no_branch;
|
|
let mut test_val = val;
|
|
if opts.len() > 0u {
|
|
alt opts[0] {
|
|
var(_, vdef) {
|
|
if (*ty::enum_variants(tcx, vdef.enm)).len() == 1u {
|
|
kind = single;
|
|
} else {
|
|
let enumptr =
|
|
PointerCast(bcx, val, T_opaque_enum_ptr(ccx));
|
|
let discrimptr = GEPi(bcx, enumptr, ~[0u, 0u]);
|
|
test_val = Load(bcx, discrimptr);
|
|
kind = switch;
|
|
}
|
|
}
|
|
lit(l) {
|
|
test_val = Load(bcx, val);
|
|
let pty = node_id_type(bcx, pat_id);
|
|
kind = if ty::type_is_integral(pty) { switch }
|
|
else { compare };
|
|
}
|
|
range(_, _) {
|
|
test_val = Load(bcx, val);
|
|
kind = compare;
|
|
}
|
|
}
|
|
}
|
|
for vec::each(opts) |o| {
|
|
alt o {
|
|
range(_, _) { kind = compare; break; }
|
|
_ { }
|
|
}
|
|
}
|
|
let else_cx = alt kind {
|
|
no_branch | single { bcx }
|
|
_ { sub_block(bcx, ~"match_else") }
|
|
};
|
|
let sw = if kind == switch {
|
|
Switch(bcx, test_val, else_cx.llbb, opts.len())
|
|
} else { C_int(ccx, 0) }; // Placeholder for when not using a switch
|
|
|
|
let defaults = enter_default(dm, m, col, val);
|
|
let exhaustive = option::is_none(chk) && defaults.len() == 0u;
|
|
let len = opts.len();
|
|
let mut i = 0u;
|
|
// Compile subtrees for each option
|
|
for vec::each(opts) |opt| {
|
|
i += 1u;
|
|
let mut opt_cx = else_cx;
|
|
if !exhaustive || i < len {
|
|
opt_cx = sub_block(bcx, ~"match_case");
|
|
alt kind {
|
|
single { Br(bcx, opt_cx.llbb); }
|
|
switch {
|
|
alt check trans_opt(bcx, opt) {
|
|
single_result(r) {
|
|
llvm::LLVMAddCase(sw, r.val, opt_cx.llbb);
|
|
bcx = r.bcx;
|
|
}
|
|
}
|
|
}
|
|
compare {
|
|
let t = node_id_type(bcx, pat_id);
|
|
let {bcx: after_cx, val: matches} = {
|
|
do with_scope_result(bcx, none, ~"compare_scope") |bcx| {
|
|
alt trans_opt(bcx, opt) {
|
|
single_result({bcx, val}) {
|
|
trans_compare(bcx, ast::eq, test_val, t, val, t)
|
|
}
|
|
range_result({val: vbegin, _}, {bcx, val: vend}) {
|
|
let {bcx, val: llge} = trans_compare(
|
|
bcx, ast::ge, test_val, t, vbegin, t);
|
|
let {bcx, val: llle} = trans_compare(
|
|
bcx, ast::le, test_val, t, vend, t);
|
|
{bcx: bcx, val: And(bcx, llge, llle)}
|
|
}
|
|
}
|
|
}
|
|
};
|
|
bcx = sub_block(after_cx, ~"compare_next");
|
|
CondBr(after_cx, matches, opt_cx.llbb, bcx.llbb);
|
|
}
|
|
_ { }
|
|
}
|
|
} else if kind == compare { Br(bcx, else_cx.llbb); }
|
|
let mut size = 0u;
|
|
let mut unpacked = ~[];
|
|
alt opt {
|
|
var(_, vdef) {
|
|
let args = extract_variant_args(opt_cx, pat_id, vdef, val);
|
|
size = args.vals.len();
|
|
unpacked = args.vals;
|
|
opt_cx = args.bcx;
|
|
}
|
|
lit(_) | range(_, _) { }
|
|
}
|
|
compile_submatch(opt_cx, enter_opt(tcx, m, opt, col, size, val),
|
|
vec::append(unpacked, vals_left), chk, exits);
|
|
}
|
|
|
|
// Compile the fall-through case, if any
|
|
if !exhaustive {
|
|
if kind == compare { Br(bcx, else_cx.llbb); }
|
|
if kind != single {
|
|
compile_submatch(else_cx, defaults, vals_left, chk, exits);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Returns false for unreachable blocks
|
|
fn make_phi_bindings(bcx: block, map: ~[exit_node],
|
|
ids: pat_util::pat_id_map) -> bool {
|
|
let _icx = bcx.insn_ctxt(~"alt::make_phi_bindings");
|
|
let our_block = bcx.llbb as uint;
|
|
let mut success = true, bcx = bcx;
|
|
for ids.each |name, node_id| {
|
|
let mut llbbs = ~[];
|
|
let mut vals = ~[];
|
|
for vec::each(map) |ex| {
|
|
if ex.to as uint == our_block {
|
|
alt assoc(name, ex.bound) {
|
|
some(val) {
|
|
vec::push(llbbs, ex.from);
|
|
vec::push(vals, val);
|
|
}
|
|
none { }
|
|
}
|
|
}
|
|
}
|
|
if vals.len() > 0u {
|
|
let local = Phi(bcx, val_ty(vals[0]), vals, llbbs);
|
|
bcx.fcx.lllocals.insert(node_id, local_mem(local));
|
|
} else { success = false; }
|
|
};
|
|
if !success {
|
|
Unreachable(bcx);
|
|
}
|
|
ret success;
|
|
}
|
|
|
|
fn trans_alt(bcx: block,
|
|
alt_expr: @ast::expr,
|
|
expr: @ast::expr,
|
|
arms: ~[ast::arm],
|
|
mode: ast::alt_mode,
|
|
dest: dest) -> block {
|
|
let _icx = bcx.insn_ctxt(~"alt::trans_alt");
|
|
do with_scope(bcx, alt_expr.info(), ~"alt") |bcx| {
|
|
trans_alt_inner(bcx, expr, arms, mode, dest)
|
|
}
|
|
}
|
|
|
|
fn trans_alt_inner(scope_cx: block, expr: @ast::expr, arms: ~[ast::arm],
|
|
mode: ast::alt_mode, dest: dest) -> block {
|
|
let _icx = scope_cx.insn_ctxt(~"alt::trans_alt_inner");
|
|
let bcx = scope_cx, tcx = bcx.tcx();
|
|
let mut bodies = ~[], match = ~[];
|
|
|
|
let {bcx, val, _} = trans_temp_expr(bcx, expr);
|
|
if bcx.unreachable { ret bcx; }
|
|
|
|
for vec::each(arms) |a| {
|
|
let body = scope_block(bcx, a.body.info(), ~"case_body");
|
|
let id_map = pat_util::pat_id_map(tcx.def_map, a.pats[0]);
|
|
vec::push(bodies, body);
|
|
for vec::each(a.pats) |p| {
|
|
vec::push(match, @{pats: ~[p],
|
|
bound: ~[],
|
|
data: @{bodycx: body, guard: a.guard,
|
|
id_map: id_map}});
|
|
}
|
|
}
|
|
|
|
let mk_fail = alt mode {
|
|
ast::alt_check {
|
|
// Cached fail-on-fallthrough block
|
|
let fail_cx = @mut none;
|
|
fn mk_fail(bcx: block, sp: span,
|
|
done: @mut option<BasicBlockRef>) -> BasicBlockRef {
|
|
alt *done { some(bb) { ret bb; } _ { } }
|
|
let fail_cx = sub_block(bcx, ~"case_fallthrough");
|
|
trans_fail(fail_cx, some(sp), ~"non-exhaustive match failure");;
|
|
*done = some(fail_cx.llbb);
|
|
ret fail_cx.llbb;
|
|
}
|
|
some(|| mk_fail(scope_cx, expr.span, fail_cx))
|
|
}
|
|
ast::alt_exhaustive { none }
|
|
};
|
|
let mut exit_map = ~[];
|
|
let t = node_id_type(bcx, expr.id);
|
|
let spilled = spill_if_immediate(bcx, val, t);
|
|
compile_submatch(bcx, match, ~[spilled], mk_fail, exit_map);
|
|
|
|
let mut arm_cxs = ~[], arm_dests = ~[], i = 0u;
|
|
for vec::each(arms) |a| {
|
|
let body_cx = bodies[i];
|
|
let id_map = pat_util::pat_id_map(tcx.def_map, a.pats[0]);
|
|
if make_phi_bindings(body_cx, exit_map, id_map) {
|
|
let arm_dest = dup_for_join(dest);
|
|
vec::push(arm_dests, arm_dest);
|
|
let mut arm_cx = trans_block(body_cx, a.body, arm_dest);
|
|
arm_cx = trans_block_cleanups(arm_cx, body_cx);
|
|
vec::push(arm_cxs, arm_cx);
|
|
}
|
|
i += 1u;
|
|
}
|
|
join_returns(scope_cx, arm_cxs, arm_dests, dest)
|
|
}
|
|
|
|
// Not alt-related, but similar to the pattern-munging code above
|
|
fn bind_irrefutable_pat(bcx: block, pat: @ast::pat, val: ValueRef,
|
|
make_copy: bool) -> block {
|
|
let _icx = bcx.insn_ctxt(~"alt::bind_irrefutable_pat");
|
|
let ccx = bcx.fcx.ccx;
|
|
let mut bcx = bcx;
|
|
|
|
// Necessary since bind_irrefutable_pat is called outside trans_alt
|
|
alt pat.node {
|
|
ast::pat_ident(_,inner) {
|
|
if pat_is_variant(bcx.tcx().def_map, pat) { ret bcx; }
|
|
if make_copy {
|
|
let ty = node_id_type(bcx, pat.id);
|
|
let llty = type_of::type_of(ccx, ty);
|
|
let alloc = alloca(bcx, llty);
|
|
bcx = copy_val(bcx, INIT, alloc,
|
|
load_if_immediate(bcx, val, ty), ty);
|
|
bcx.fcx.lllocals.insert(pat.id, local_mem(alloc));
|
|
add_clean(bcx, alloc, ty);
|
|
} else { bcx.fcx.lllocals.insert(pat.id, local_mem(val)); }
|
|
alt inner {
|
|
some(pat) { bcx = bind_irrefutable_pat(bcx, pat, val, true); }
|
|
_ {}
|
|
}
|
|
}
|
|
ast::pat_enum(_, sub) {
|
|
let vdefs = ast_util::variant_def_ids(ccx.tcx.def_map.get(pat.id));
|
|
let args = extract_variant_args(bcx, pat.id, vdefs, val);
|
|
let mut i = 0;
|
|
do option::iter(sub) |sub| { for vec::each(args.vals) |argval| {
|
|
bcx = bind_irrefutable_pat(bcx, sub[i], argval, make_copy);
|
|
i += 1;
|
|
}}
|
|
}
|
|
ast::pat_rec(fields, _) {
|
|
let rec_fields = ty::get_fields(node_id_type(bcx, pat.id));
|
|
for vec::each(fields) |f| {
|
|
let ix = option::get(ty::field_idx(f.ident, rec_fields));
|
|
let fldptr = GEPi(bcx, val, ~[0u, ix]);
|
|
bcx = bind_irrefutable_pat(bcx, f.pat, fldptr, make_copy);
|
|
}
|
|
}
|
|
ast::pat_tup(elems) {
|
|
let mut i = 0u;
|
|
for vec::each(elems) |elem| {
|
|
let fldptr = GEPi(bcx, val, ~[0u, i]);
|
|
bcx = bind_irrefutable_pat(bcx, elem, fldptr, make_copy);
|
|
i += 1u;
|
|
}
|
|
}
|
|
ast::pat_box(inner) {
|
|
let llbox = Load(bcx, val);
|
|
let unboxed =
|
|
GEPi(bcx, llbox, ~[0u, abi::box_field_body]);
|
|
bcx = bind_irrefutable_pat(bcx, inner, unboxed, true);
|
|
}
|
|
ast::pat_uniq(inner) {
|
|
let llbox = Load(bcx, val);
|
|
let unboxed =
|
|
GEPi(bcx, llbox, ~[0u, abi::box_field_body]);
|
|
bcx = bind_irrefutable_pat(bcx, inner, unboxed, true);
|
|
}
|
|
ast::pat_wild | ast::pat_lit(_) | ast::pat_range(_, _) { }
|
|
}
|
|
ret bcx;
|
|
}
|
|
|
|
// Local Variables:
|
|
// mode: rust
|
|
// fill-column: 78;
|
|
// indent-tabs-mode: nil
|
|
// c-basic-offset: 4
|
|
// buffer-file-coding-system: utf-8-unix
|
|
// End:
|