kjuulh/rhai
1
0
Fork 0
Code Issues 1 Pull Requests 1 Packages Projects Releases Wiki Activity

Skip evaluate condition for loop statement.

Browse Source
This commit is contained in:
Stephen Chung
2021-03-06 16:05:22 +08:00
parent e14bef4b10
commit a126d05c3f
4 changed files with 48 additions and 35 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
src/optimize.rs
View File

@@ -393,25 +393,32 @@ fn optimize_stmt(stmt: &mut Stmt, state: &mut State, preserve_result: bool) {
}
// while false { block } -> Noop
Stmt::While(Expr::BoolConstant(false, pos), _, _) => {
Stmt::While(Some(Expr::BoolConstant(false, pos)), _, _) => {
state.set_dirty();
*stmt = Stmt::Noop(*pos)
}
// while expr { block }
Stmt::While(condition, block, _) => {
optimize_stmt(block, state, false);
optimize_expr(condition, state);
if let Some(condition) = condition {
optimize_expr(condition, state);
}
match **block {
// while expr { break; } -> { expr; }
Stmt::Break(pos) => {
// Only a single break statement - turn into running the guard expression once
state.set_dirty();
let mut statements = vec![Stmt::Expr(mem::take(condition))];
if preserve_result {
statements.push(Stmt::Noop(pos))
}
*stmt = Stmt::Block(statements, pos);
if let Some(condition) = condition {
let mut statements = vec![Stmt::Expr(mem::take(condition))];
if preserve_result {
statements.push(Stmt::Noop(pos))
}
*stmt = Stmt::Block(statements, pos);
} else {
*stmt = Stmt::Noop(pos);
};
}
_ => (),
}