Bug 195181

Summary:

cloop.rb shift mask should depend on the word size being shifted.

Product:

WebKit

Reporter:

Mark Lam <mark.lam>

Component:

JavaScriptCore

Assignee:

Mark Lam <mark.lam>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

ews-watchlist, keith_miller, mitya57, msaboff, ryanhaddad, saam, webkit-bug-importer, ysuzuki

Priority:

Keywords:

InRadar

Version:

WebKit Nightly Build

Hardware:

Unspecified

OS:

Unspecified

Attachments:

Description	Flags
proposed patch.	ysuzuki: review+

Description Mark Lam 2019-02-28 12:29:41 PST

Previously, we're always masking the shift amount with 0x1f.  This only works for 32-bit words.  For 64-bit words, the mask should be 0x3f.  For intptr_t shifts, the mask depends on sizeof(uintptr_t).

Comment 1 Radar WebKit Bug Importer 2019-02-28 12:30:06 PST

<rdar://problem/48484164>

Comment 2 Mark Lam 2019-02-28 12:35:11 PST

Created attachment 363250 [details]
proposed patch.

Comment 3 Yusuke Suzuki 2019-02-28 12:45:10 PST

Comment on attachment 363250 [details]
proposed patch.

View in context: https://bugs.webkit.org/attachment.cgi?id=363250&action=review

r=me

> Source/JavaScriptCore/offlineasm/cloop.rb:429
> +    shiftMask = "((sizeof(uintptr_t) == 8) ? 0x3f : 0x1f)" if type == :int || type == :uint

Discussed with Mark. The type ":int" and ":uint" actually means "intptr_t" and "uintptr_t". Then this is correct.
It is nice if we have either of
1. Add a comment about it here now, and rename ":int" => ":intPtr" or something like that in a subsequent patch.
2. Rename them in this patch too.

Comment 4 Mark Lam 2019-02-28 12:49:35 PST

Thanks for the review.  I added the FIXME.  Landed in r242215: <http://trac.webkit.org/r242215>.

Comment 5 Mark Lam 2019-02-28 12:51:16 PST

*** Bug 195175 has been marked as a duplicate of this bug. ***

Comment 6 Alberto Garcia 2019-07-17 05:58:56 PDT

*** Bug 199684 has been marked as a duplicate of this bug. ***