aboutsummaryrefslogtreecommitdiff
path: root/lib
diff options
context:
space:
mode:
Diffstat (limited to 'lib')
-rw-r--r--lib/compress.js45
1 files changed, 34 insertions, 11 deletions
diff --git a/lib/compress.js b/lib/compress.js
index 6d398de2..fb7e66de 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -4718,8 +4718,8 @@ merge(Compressor.prototype, {
});
function if_break_in_loop(self, compressor) {
- var first = self.body instanceof AST_BlockStatement ? self.body.body[0] : self.body;
- if (compressor.option("dead_code") && is_break(first)) {
+ var first = first_statement(self.body);
+ if (compressor.option("dead_code") && (breaks(first) || first instanceof AST_Exit)) {
var body = [];
if (self.init instanceof AST_Statement) {
body.push(self.init);
@@ -4728,10 +4728,19 @@ merge(Compressor.prototype, {
body: self.init
}));
}
- if (self.condition) {
+ var retain = external_target(first) || first instanceof AST_Exit;
+ if (self.condition && retain) {
+ body.push(make_node(AST_If, self, {
+ condition: self.condition,
+ body: first,
+ alternative: null
+ }));
+ } else if (self.condition) {
body.push(make_node(AST_SimpleStatement, self.condition, {
body: self.condition
}));
+ } else if (retain) {
+ body.push(first);
}
extract_declarations_from_unreachable_code(self.body, body);
return make_node(AST_BlockStatement, self, {
@@ -4739,7 +4748,8 @@ merge(Compressor.prototype, {
});
}
if (first instanceof AST_If) {
- if (is_break(first.body)) {
+ var ab = first_statement(first.body);
+ if (breaks(ab)) {
if (self.condition) {
self.condition = make_node(AST_Binary, self.condition, {
left: self.condition,
@@ -4749,8 +4759,12 @@ merge(Compressor.prototype, {
} else {
self.condition = first.condition.negate(compressor);
}
- drop_it(first.alternative);
- } else if (is_break(first.alternative)) {
+ var body = as_statement_array(first.alternative);
+ extract_declarations_from_unreachable_code(first.body, body);
+ return drop_it(body);
+ }
+ ab = first_statement(first.alternative);
+ if (breaks(ab)) {
if (self.condition) {
self.condition = make_node(AST_Binary, self.condition, {
left: self.condition,
@@ -4760,18 +4774,27 @@ merge(Compressor.prototype, {
} else {
self.condition = first.condition;
}
- drop_it(first.body);
+ var body = as_statement_array(first.body);
+ extract_declarations_from_unreachable_code(first.alternative, body);
+ return drop_it(body);
}
}
return self;
- function is_break(node) {
+ function first_statement(body) {
+ return body instanceof AST_BlockStatement ? body.body[0] : body;
+ }
+
+ function external_target(node) {
+ return compressor.loopcontrol_target(node) !== compressor.self();
+ }
+
+ function breaks(node) {
return node instanceof AST_Break
- && compressor.loopcontrol_target(node) === compressor.self();
+ || node instanceof AST_Continue && external_target(node);
}
function drop_it(rest) {
- rest = as_statement_array(rest);
if (self.body instanceof AST_BlockStatement) {
self.body = self.body.clone();
self.body.body = rest.concat(self.body.body.slice(1));
@@ -4781,7 +4804,7 @@ merge(Compressor.prototype, {
body: rest
}).transform(compressor);
}
- self = if_break_in_loop(self, compressor);
+ return if_break_in_loop(self, compressor);
}
}