Skip to content

_match.rs: improve enter_opt #13169

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 1 commit into from
Closed

_match.rs: improve enter_opt #13169

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
17 changes: 6 additions & 11 deletions src/librustc/middle/trans/_match.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -620,14 +620,15 @@ fn enter_opt<'a, 'b>(
m: &'a [Match<'a, 'b>],
opt: &Opt,
col: uint,
row: uint,
variant_size: uint,
val: ValueRef)
-> Vec<Match<'a, 'b>> {
debug!("enter_opt(bcx={}, m={}, opt={:?}, col={}, val={})",
debug!("enter_opt(bcx={}, m={}, opt={:?}, col={}, row={}, val={})",
bcx.to_str(),
m.repr(bcx.tcx()),
*opt,
col,
col, row,
bcx.val_to_str(val));
let _indenter = indenter();

Expand All @@ -639,14 +640,8 @@ fn enter_opt<'a, 'b>(
// comes to literal or range, that strategy may lead to wrong result if there
// are guard function or multiple patterns inside tuple; in that case, pruning
// based on the overlap of patterns is required.
//
// Ideally, when constructing the sub-match tree for certain arm, only those
// arms beneath it matter. But that isn't how algorithm works right now and
// all other arms are taken into consideration when computing `guarded` below.
// That is ok since each round of `compile_submatch` guarantees to trim one
// "column" of arm patterns and the algorithm will converge.
let guarded = m.iter().any(|x| x.data.arm.guard.is_some());
let multi_pats = m.len() > 0 && m[0].pats.len() > 1;
let guarded = m[row].data.arm.guard.is_some();
let multi_pats = m[0].pats.len() > 1;
enter_match(bcx, &tcx.def_map, m, col, val, |p| {
let answer = match p.node {
ast::PatEnum(..) |
Expand Down Expand Up @@ -1807,7 +1802,7 @@ fn compile_submatch_continue<'a, 'b>(
}
lit(_) | range(_, _) => ()
}
let opt_ms = enter_opt(opt_cx, m, opt, col, size, val);
let opt_ms = enter_opt(opt_cx, m, opt, col, i, size, val);
let opt_vals = unpacked.append(vals_left.as_slice());

match branch_chk {
Expand Down