349663 - Function with const and *= changes during uneval-eval round trip

Status: VERIFIED FIXED

(Core :: JavaScript Engine, defect)

Description

[Jesse Ruderman]

> function() { const h; for(null; h *= ""; null) ; }
function () { const h; for (null; h * ""; null) { } }

> function () { const h; for (null; h * ""; null) { } }
function () { const h; for (null; h * 0; null) { } }

It would be nice if the "" became 0 the first time.  My fuzzer in bug 349611 depends on functions not changing during round-trips in order to find "real" bugs in the decompiler.

Comment 1

[Brendan Eich [:brendan]]

Attachment: fix

Easy patch to fold constants more thoroughly: the operands of assignment operators such as *=, and all operands of a chained expression of same precedence and left associativity (represented as a list to avoid binary tree space cost and recursive depth hazard).

/be

Comment 2

[Mike Shaver (:shaver emeritus)]

Comment on attachment 235190 [details] [diff] [review]
fix

r=shaver

Comment 3

[Brendan Eich [:brendan]]

Fixed on trunk.

Checking in jsparse.c;
/cvsroot/mozilla/js/src/jsparse.c,v  <--  jsparse.c
new revision: 3.210; previous revision: 3.209
done

/be

Comment 4

[Mike Beltzner [:beltzner, not reading bugmail]]

Comment on attachment 235190 [details] [diff] [review]
fix

a=beltzner on behalf of the 181drivers

Comment 5

[Brendan Eich [:brendan]]

Fixed on the 1.8 branch.

/be

Comment 6

[Bob Clary [:bc] (inactive)]

Checking in regress-349663.js;
/cvsroot/mozilla/js/tests/js1_5/Regress/regress-349663.js,v  <--  regress-349663.js
initial revision: 1.1

Comment 7

[Bob Clary [:bc] (inactive)]

verified fixed 1.8 20060827 windows/mac*/linux

note 1.8 passes with
expected: function () {     const h;     for (null; h * 0; null) {     } } 
actual: function () {     const h;     for (null; h * 0; null) {     } }

1.8.0.7 passes with
expected: function () {     const h;     for (null; ""; null) {     } } 
actual: function () {     const h;     for (null; ""; null) {     } }

Comment 8

[Bob Clary [:bc] (inactive)]

verified fixed 1.9 20060827 windows/mac*/linux