diff options
| -rw-r--r-- | src/Makefile | 1 | ||||
| -rw-r--r-- | src/boot/me/trans.ml | 45 | ||||
| -rw-r--r-- | src/test/run-pass/alt-pattern-drop.rs | 19 |
3 files changed, 55 insertions, 10 deletions
diff --git a/src/Makefile b/src/Makefile index 77045777..62fe0bee 100644 --- a/src/Makefile +++ b/src/Makefile @@ -425,6 +425,7 @@ TEST_XFAILS_LLVM := $(TASK_XFAILS) \ $(addprefix test/run-pass/, \ arith-1.rs \ acyclic-unwind.rs \ + alt-pattern-drop.rs \ alt-pattern-simple.rs \ alt-tag.rs \ append-units.rs \ diff --git a/src/boot/me/trans.ml b/src/boot/me/trans.ml index 39cfd0f4..edb86294 100644 --- a/src/boot/me/trans.ml +++ b/src/boot/me/trans.ml @@ -4138,12 +4138,24 @@ let trans_visitor let trans_arm arm : quad_idx = let (pat, block) = arm.node in - (* Translates the pattern and returns the addresses of the branch - * instructions, which are taken if the match fails. *) - let rec trans_pat pat src_cell src_ty = + + (* Translates the pattern and returns the following pair. + * + * fst: The addresses of the branch instructions that are taken if + * the match fails. + * snd: The (cell, slot) pairs of any slots bound and initialized + * in PAT_slot pattern leaves. + *) + let rec trans_pat + (pat:Ast.pat) + (src_cell:Il.cell) + (src_ty:Ast.ty) + : (quad_idx list) * ((Il.cell * Ast.slot) list) = + match pat with Ast.PAT_lit lit -> - trans_compare_simple Il.JNE (trans_lit lit) (Il.Cell src_cell) + (trans_compare_simple Il.JNE (trans_lit lit) (Il.Cell src_cell), + []) | Ast.PAT_tag (lval, pats) -> let tag_name = tag_ctor_name_to_tag_name (lval_to_name lval) in @@ -4173,7 +4185,8 @@ let trans_visitor let tup_cell:Il.cell = get_variant_ptr union_cell tag_number in - let trans_elem_pat i elem_pat : quad_idx list = + let trans_elem_pat i elem_pat + : (quad_idx list) * ((Il.cell * Ast.slot) list) = let elem_cell = get_element_ptr_dyn_in_current_frame tup_cell i in @@ -4181,8 +4194,10 @@ let trans_visitor trans_pat elem_pat elem_cell elem_ty in - let elem_jumps = Array.mapi trans_elem_pat pats in - next_jumps @ (List.concat (Array.to_list elem_jumps)) + let (elem_jumps, bindings) = + List.split (Array.to_list (Array.mapi trans_elem_pat pats)) + in + (next_jumps @ (List.concat elem_jumps), List.concat bindings) | Ast.PAT_slot (dst, _) -> let dst_slot = get_slot cx dst.id in @@ -4191,14 +4206,24 @@ let trans_visitor (get_ty_params_of_current_frame()) CLONE_none dst_cell dst_slot src_cell src_ty; - [] (* irrefutable *) + ([], [(dst_cell, dst_slot)]) (* irrefutable *) - | Ast.PAT_wild -> [] (* irrefutable *) + | Ast.PAT_wild -> ([], []) (* irrefutable *) in let (lval_cell, lval_ty) = trans_lval at.Ast.alt_tag_lval in - let next_jumps = trans_pat pat lval_cell lval_ty in + let (next_jumps, bindings) = trans_pat pat lval_cell lval_ty in trans_block block; + + (* Drop any slots we initialized in the leaf slot bindings of + * this arm's pattern. + * + * FIXME: Is `None` really correct to pass as the curr_iso? + *) + List.iter + (fun (cell, slot) -> drop_slot_in_current_frame cell slot None) + bindings; + let last_jump = mark() in emit (Il.jmp Il.JMP Il.CodeNone); List.iter patch next_jumps; diff --git a/src/test/run-pass/alt-pattern-drop.rs b/src/test/run-pass/alt-pattern-drop.rs new file mode 100644 index 00000000..d1f1440f --- /dev/null +++ b/src/test/run-pass/alt-pattern-drop.rs @@ -0,0 +1,19 @@ +// -*- rust -*- + +use std; +import std._str; + +type t = tag(make_t(str), clam()); + +fn main() { + let str s = "hi"; // ref up + let t x = make_t(s); // ref up + + alt (x) { + case (make_t(y)) { log y; } // ref up and ref down + case (_) { log "?"; } + } + + log _str.refcount(s); + check (_str.refcount(s) == 2u); +} |