Skip to content

Commit

Permalink
feat(minifier): minimize if(foo) bar else baz -> foo ? bar : baz (#…
Browse files Browse the repository at this point in the history 
…8133)
  • Loading branch information
@Boshen
Boshen committed Dec 26, 2024
1 parent f615bfa commit 6b51e6d
Show file tree
Hide file tree
Showing 2 changed files with 74 additions and 44 deletions.
94 changes: 62 additions & 32 deletions crates/oxc_minifier/src/ast_passes/peephole_minimize_conditions.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -89,47 +89,53 @@ impl<'a> PeepholeMinimizeConditions {
ctx: &mut TraverseCtx<'a>,
) -> Option<Statement<'a>> {
let Statement::IfStatement(if_stmt) = stmt else { unreachable!() };
if if_stmt.alternate.is_none() {
if let Some(right) = Self::is_foldable_express_block(&mut if_stmt.consequent, ctx) {
let test = ctx.ast.move_expression(&mut if_stmt.test);
// `if(!x) foo()` -> `x || foo()`
if let Expression::UnaryExpression(unary_expr) = test {
if unary_expr.operator.is_not() {
let left = unary_expr.unbox().argument;
match &if_stmt.alternate {
None => {
if Self::is_foldable_express_block(&if_stmt.consequent) {
let right = Self::get_block_expression(&mut if_stmt.consequent, ctx);
let test = ctx.ast.move_expression(&mut if_stmt.test);
// `if(!x) foo()` -> `x || foo()`
if let Expression::UnaryExpression(unary_expr) = test {
if unary_expr.operator.is_not() {
let left = unary_expr.unbox().argument;
let logical_expr = ctx.ast.expression_logical(
if_stmt.span,
left,
LogicalOperator::Or,
right,
);
return Some(ctx.ast.statement_expression(if_stmt.span, logical_expr));
}
} else {
// `if(x) foo()` -> `x && foo()`
let logical_expr = ctx.ast.expression_logical(
if_stmt.span,
left,
LogicalOperator::Or,
test,
LogicalOperator::And,
right,
);
return Some(ctx.ast.statement_expression(if_stmt.span, logical_expr));
}
} else {
// `if(x) foo()` -> `x && foo()`
let logical_expr =
ctx.ast.expression_logical(if_stmt.span, test, LogicalOperator::And, right);
return Some(ctx.ast.statement_expression(if_stmt.span, logical_expr));
}
}
}
None
}

fn is_foldable_express_block(
stmt: &mut Statement<'a>,
ctx: &mut TraverseCtx<'a>,
) -> Option<Expression<'a>> {
match stmt {
Statement::BlockStatement(block_stmt) if block_stmt.body.len() == 1 => {
if let Statement::ExpressionStatement(s) = &mut block_stmt.body[0] {
Some(ctx.ast.move_expression(&mut s.expression))
} else {
None
Some(else_branch) => {
let then_branch_is_expression_block =
Self::is_foldable_express_block(&if_stmt.consequent);
let else_branch_is_expression_block = Self::is_foldable_express_block(else_branch);
// `if(foo) bar else baz` -> `foo ? bar : baz`
if then_branch_is_expression_block && else_branch_is_expression_block {
let test = ctx.ast.move_expression(&mut if_stmt.test);
let consequent = Self::get_block_expression(&mut if_stmt.consequent, ctx);
let else_branch = if_stmt.alternate.as_mut().unwrap();
let alternate = Self::get_block_expression(else_branch, ctx);
let expr =
ctx.ast.expression_conditional(if_stmt.span, test, consequent, alternate);
return Some(ctx.ast.statement_expression(if_stmt.span, expr));
}
}
Statement::ExpressionStatement(s) => Some(ctx.ast.move_expression(&mut s.expression)),
_ => None,
}

None
}

fn try_replace_if(&mut self, stmts: &mut Vec<'a, Statement<'a>>, ctx: &mut TraverseCtx<'a>) {
Expand Down Expand Up @@ -177,6 +183,30 @@ impl<'a> PeepholeMinimizeConditions {
}
}

fn is_foldable_express_block(stmt: &Statement<'a>) -> bool {
match stmt {
Statement::BlockStatement(block_stmt) if block_stmt.body.len() == 1 => {
matches!(&block_stmt.body[0], Statement::ExpressionStatement(_))
}
Statement::ExpressionStatement(_) => true,
_ => false,
}
}

fn get_block_expression(stmt: &mut Statement<'a>, ctx: &mut TraverseCtx<'a>) -> Expression<'a> {
match stmt {
Statement::BlockStatement(block_stmt) if block_stmt.body.len() == 1 => {
if let Statement::ExpressionStatement(s) = &mut block_stmt.body[0] {
ctx.ast.move_expression(&mut s.expression)
} else {
unreachable!()
}
}
Statement::ExpressionStatement(s) => ctx.ast.move_expression(&mut s.expression),
_ => unreachable!(),
}
}

fn is_return_block(stmt: &Statement<'a>) -> bool {
match stmt {
Statement::BlockStatement(block_stmt) if block_stmt.body.len() == 1 => {
Expand Down Expand Up @@ -271,7 +301,7 @@ mod test {

// Try it out with functions
fold("function f(){if(x){foo()}}", "function f(){x&&foo()}");
// fold("function f(){if(x){foo()}else{bar()}}", "function f(){x?foo():bar()}");
fold("function f(){if(x){foo()}else{bar()}}", "function f(){x?foo():bar()}");

// Try it out with properties and methods
fold("function f(){if(x){a.b=1}}", "function f(){x&&(a.b=1)}");
Expand All @@ -288,7 +318,7 @@ mod test {
fold_same("function f(){switch(x){case 1:break}}");

// Do while loops stay in a block if that's where they started
// fold_same("function f(){if(e1){do foo();while(e2)}else foo2()}");
fold_same("function f(){if(e1){do foo();while(e2)}else foo2()}");
// Test an obscure case with do and while
// fold("if(x){do{foo()}while(y)}else bar()", "if(x){do foo();while(y)}else bar()");

Expand Down
24 changes: 12 additions & 12 deletions tasks/minsize/minsize.snap
View file
Original file line number Diff line number Diff line change
@@ -1,27 +1,27 @@
| Oxc | ESBuild | Oxc | ESBuild |
Original | minified | minified | gzip | gzip | Fixture
-------------------------------------------------------------------------------------
72.14 kB | 23.85 kB | 23.70 kB | 8.64 kB | 8.54 kB | react.development.js
72.14 kB | 23.77 kB | 23.70 kB | 8.62 kB | 8.54 kB | react.development.js

173.90 kB | 60.60 kB | 59.82 kB | 19.54 kB | 19.33 kB | moment.js
173.90 kB | 60.22 kB | 59.82 kB | 19.49 kB | 19.33 kB | moment.js

287.63 kB | 91.40 kB | 90.07 kB | 32.36 kB | 31.95 kB | jquery.js
287.63 kB | 90.77 kB | 90.07 kB | 32.23 kB | 31.95 kB | jquery.js

342.15 kB | 120.07 kB | 118.14 kB | 44.79 kB | 44.37 kB | vue.js
342.15 kB | 119.00 kB | 118.14 kB | 44.65 kB | 44.37 kB | vue.js

544.10 kB | 72.91 kB | 72.48 kB | 26.27 kB | 26.20 kB | lodash.js
544.10 kB | 72.54 kB | 72.48 kB | 26.23 kB | 26.20 kB | lodash.js

555.77 kB | 275.31 kB | 270.13 kB | 91.45 kB | 90.80 kB | d3.js
555.77 kB | 274.27 kB | 270.13 kB | 91.27 kB | 90.80 kB | d3.js

1.01 MB | 462.98 kB | 458.89 kB | 127.06 kB | 126.71 kB | bundle.min.js
1.01 MB | 461.18 kB | 458.89 kB | 126.93 kB | 126.71 kB | bundle.min.js

1.25 MB | 658.98 kB | 646.76 kB | 164.40 kB | 163.73 kB | three.js
1.25 MB | 657.26 kB | 646.76 kB | 164.24 kB | 163.73 kB | three.js

2.14 MB | 736.98 kB | 724.14 kB | 181.33 kB | 181.07 kB | victory.js
2.14 MB | 735.73 kB | 724.14 kB | 181.11 kB | 181.07 kB | victory.js

3.20 MB | 1.02 MB | 1.01 MB | 332.77 kB | 331.56 kB | echarts.js
3.20 MB | 1.01 MB | 1.01 MB | 332.37 kB | 331.56 kB | echarts.js

6.69 MB | 2.38 MB | 2.31 MB | 495.91 kB | 488.28 kB | antd.js
6.69 MB | 2.38 MB | 2.31 MB | 495.35 kB | 488.28 kB | antd.js

10.95 MB | 3.52 MB | 3.49 MB | 911.59 kB | 915.50 kB | typescript.js
10.95 MB | 3.52 MB | 3.49 MB | 911.00 kB | 915.50 kB | typescript.js

0 comments on commit 6b51e6d

Please sign in to comment.