code review 6249048: cmd/cc: fix uint right shift in constant propagation

cmd/cc: fix uint right shift in constant evaluation
        Fixes issue 3664.

[minux1, 2012-05-24 15:58:31]

Hello golang-dev@googlegroups.com (cc: golang-dev@googlegroups.com),

I'd like you to review this change to
https://code.google.com/p/go/

[bradfitz, 2012-05-24 16:01:03]

Test?  (question, not request.  how/where are tests for cc?)

On Thu, May 24, 2012 at 8:58 AM, <minux.ma@gmail.com> wrote:

> Reviewers: golang-dev_googlegroups.com,
>
> Message:
> Hello golang-dev@googlegroups.com (cc: golang-dev@googlegroups.com),
>
> I'd like you to review this change to
> https://code.google.com/p/go/
>
>
> Description:
> cmd/cc: fix uint right shift in constant propagation
>        Fixes issue 3664.
>
> Please review this at
http://codereview.appspot.com/**6249048/<http://codereview.appspot.com/6249048/>
>
> Affected files:
>  src/cmd/cc/scon.c
>
>
> Index: src/cmd/cc/scon.c
> ==============================**==============================**=======
> --- a/src/cmd/cc/scon.c
> +++ b/src/cmd/cc/scon.c
> @@ -175,7 +175,10 @@
>                break;
>
>        case OLSHR:
> -               v = (uvlong)l->vconst >> r->vconst;
> +               if(l->type->width != sizeof(uvlong))
> +                       v = ((uvlong)l->vconst & 0xffffffffULL) >>
> r->vconst;
> +               else
> +                       v = (uvlong)l->vconst >> r->vconst;
>                break;
>
>        case OASHR:
>
>
>

[rsc, 2012-05-24 16:01:51]

LGTM

Please change 'propagation' to 'evaluation' in the CL description.

[minux1, 2012-05-24 16:08:38]

On Fri, May 25, 2012 at 12:01 AM, Brad Fitzpatrick <bradfitz@golang.org>wrote:

> Test?  (question, not request.  how/where are tests for cc?)

I wish we have tests for cc....

[minux1, 2012-05-24 16:09:07]

*** Submitted as http://code.google.com/p/go/source/detail?r=aa2d2fa1e5a9 ***

cmd/cc: fix uint right shift in constant evaluation
        Fixes issue 3664.

R=golang-dev, bradfitz, rsc
CC=golang-dev
http://codereview.appspot.com/6249048