1311633 - Add a testing function that dumps RegExp bytecode.

Status: RESOLVED FIXED

(Core :: JavaScript Engine, enhancement)

Description

[Tooru Fujisawa [:arai]]

It would be nice to have a shell-only testing function that dumps RegExp bytecode for given pattern, flags, mode, and input.

Comment 1

[Tooru Fujisawa [:arai]]

Attachment: Add dis_regexp shell-only testing function.

dis_regexp dumps bytecode for given RegExp object, with match_only boolean and sample input (bytecode differs for input, especially latin1 or not).

unfortunately this cannot be done outside of RegExpObject or RegExpShared.
so I added RegExpShared::dumpBytecode.

it dumps bytecode, in the same format as dis() function.

the tricky part is bytecode length.
the bytecode has no information about its length, so we need to calculate the maximum PC from jumps and branches.

Comment 2

[Tooru Fujisawa [:arai]]

Attachment: Add disRegExp testing function.

Moved to TestingFunctions.cpp and renamed to disRegExp.
no other changes.

Comment 3

[Till Schneidereit [:till]]

Comment on attachment 8803848 [details] [diff] [review]
Add disRegExp testing function.

Review of attachment 8803848 [details] [diff] [review]:
-----------------------------------------------------------------

So very nice. r=me with nits addressed.

::: js/src/builtin/TestingFunctions.cpp
@@ +3929,5 @@
> +    }
> +
> +    RootedObject obj(cx, &args[0].toObject());
> +    if (!obj)
> +        return false;

This seems like it shouldn't be possible, right?

In general, I'd combine checks here into `if (!args[0].isObject() || !args[0].toObject().is<RegExpObject>())`, and then only have one block in which the "First argument must be a RegExp" error is thrown.

::: js/src/vm/RegExpObject.cpp
@@ +884,5 @@
> +        return false;
> +
> +    return g.re()->dumpBytecode(cx, match_only, input);
> +}
> +#endif

Nit: add a "// DEBUG" comment to the endif.

Comment 4

[Tooru Fujisawa [:arai]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/5792e30aaf0fdc9af40ce5c1adb6b4855a3b9070
Bug 1311633 - Add disRegExp testing function. r=till

Comment 5

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/5792e30aaf0f