Bug 136435 - offlineasm generates suboptimal code for move immediate on ARM64
Summary: offlineasm generates suboptimal code for move immediate on ARM64
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: 528+ (Nightly build)
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2014-09-01 13:51 PDT by Akos Kiss
Modified: 2014-09-03 07:15 PDT (History)
6 users (show)

See Also:

Attachments
Proposed patch. (1.84 KB, patch)
2014-09-01 14:26 PDT, Akos Kiss 		no flags Details | Formatted Diff | Diff
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Description Akos Kiss 2014-09-01 13:51:00 PDT 
emitARM64MoveImmediate generates a slightly suboptimal code if value is greater than 0xffff but the last 16 bits are all zeros, or less than ~0xffff but the last 16 bits are all ones. E.g.,

move 0xffff000000000000, csr1

in LowLevelInterpreter64.asm becomes

movz x27, #65535, lsl #48
movk x27, #0, lsl #0
Comment 1 Akos Kiss 2014-09-01 14:26:17 PDT 
Created attachment 237462 [details]
Proposed patch.
Comment 2 Michael Saboff 2014-09-03 06:40:15 PDT 
Comment on attachment 237462 [details]
Proposed patch.

r=me
Comment 3 WebKit Commit Bot 2014-09-03 07:15:21 PDT 
Comment on attachment 237462 [details]
Proposed patch.

Clearing flags on attachment: 237462

Committed r173205: <http://trac.webkit.org/changeset/173205>
Comment 4 WebKit Commit Bot 2014-09-03 07:15:25 PDT 
All reviewed patches have been landed.  Closing bug.