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* [Bug middle-end/60737] New: rs6000 expand_block_clear uses word stores on double word pointer
@ 2014-04-02 4:35 anton at samba dot org
2014-04-02 4:41 ` [Bug middle-end/60737] " anton at samba dot org
` (4 more replies)
0 siblings, 5 replies; 6+ messages in thread
From: anton at samba dot org @ 2014-04-02 4:35 UTC (permalink / raw)
To: gcc-bugs
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60737
Bug ID: 60737
Summary: rs6000 expand_block_clear uses word stores on double
word pointer
Product: gcc
Version: 4.8.3
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: anton at samba dot org
The following code:
#include <string.h>
void foo(long *p)
{
memset(p, 0, 16);
}
When built with a 64bit target:
gcc -mcpu=power8 -O2 -S foo.c
Ends up using 32 byte stores:
foo:
li 9,0
stw 9,0(3)
stw 9,4(3)
stw 9,8(3)
stw 9,12(3)
blr
expand_block_move has a similar issue
^ permalink raw reply [flat|nested] 6+ messages in thread* [Bug middle-end/60737] rs6000 expand_block_clear uses word stores on double word pointer 2014-04-02 4:35 [Bug middle-end/60737] New: rs6000 expand_block_clear uses word stores on double word pointer anton at samba dot org @ 2014-04-02 4:41 ` anton at samba dot org 2014-04-02 8:39 ` rguenth at gcc dot gnu.org ` (3 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: anton at samba dot org @ 2014-04-02 4:41 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60737 --- Comment #1 from Anton Blanchard <anton at samba dot org> --- It looks like by the time we get to expand_block_clear we don't have any alignment info (align_rtx == 1). ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug middle-end/60737] rs6000 expand_block_clear uses word stores on double word pointer 2014-04-02 4:35 [Bug middle-end/60737] New: rs6000 expand_block_clear uses word stores on double word pointer anton at samba dot org 2014-04-02 4:41 ` [Bug middle-end/60737] " anton at samba dot org @ 2014-04-02 8:39 ` rguenth at gcc dot gnu.org 2014-05-01 12:50 ` [Bug target/60737] " amodra at gmail dot com ` (2 subsequent siblings) 4 siblings, 0 replies; 6+ messages in thread From: rguenth at gcc dot gnu.org @ 2014-04-02 8:39 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60737 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |RESOLVED Resolution|--- |DUPLICATE --- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- there isn't any alignment info. *** This bug has been marked as a duplicate of bug 50417 *** ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug target/60737] rs6000 expand_block_clear uses word stores on double word pointer 2014-04-02 4:35 [Bug middle-end/60737] New: rs6000 expand_block_clear uses word stores on double word pointer anton at samba dot org 2014-04-02 4:41 ` [Bug middle-end/60737] " anton at samba dot org 2014-04-02 8:39 ` rguenth at gcc dot gnu.org @ 2014-05-01 12:50 ` amodra at gmail dot com 2014-05-08 2:07 ` amodra at gcc dot gnu.org 2014-05-08 2:14 ` amodra at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: amodra at gmail dot com @ 2014-05-01 12:50 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60737 Alan Modra <amodra at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|RESOLVED |ASSIGNED Version|4.8.3 |4.10.0 Last reconfirmed| |2014-05-01 Component|middle-end |target CC| |amodra at gmail dot com Assignee|unassigned at gcc dot gnu.org |amodra at gmail dot com Resolution|DUPLICATE |--- Ever confirmed|0 |1 --- Comment #3 from Alan Modra <amodra at gmail dot com> --- Reassigning as one aspect of this bug is target specific. If -mno-strict-align we should be using 64-bit stores regardless of the alignment info. What matters for 64-bit ld/std instructions is that when using reg+offset addressing that the offset be a multiple of 4. ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug target/60737] rs6000 expand_block_clear uses word stores on double word pointer 2014-04-02 4:35 [Bug middle-end/60737] New: rs6000 expand_block_clear uses word stores on double word pointer anton at samba dot org ` (2 preceding siblings ...) 2014-05-01 12:50 ` [Bug target/60737] " amodra at gmail dot com @ 2014-05-08 2:07 ` amodra at gcc dot gnu.org 2014-05-08 2:14 ` amodra at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: amodra at gcc dot gnu.org @ 2014-05-08 2:07 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60737 --- Comment #4 from Alan Modra <amodra at gcc dot gnu.org> --- Author: amodra Date: Thu May 8 02:05:19 2014 New Revision: 210201 URL: http://gcc.gnu.org/viewcvs?rev=210201&root=gcc&view=rev Log: PR target/60737 * config/rs6000/rs6000.c (expand_block_move): Allow 64-bit loads and stores when -mno-strict-align at any alignment. (expand_block_clear): Similarly. Also correct calculation of instruction count. Modified: trunk/gcc/ChangeLog trunk/gcc/config/rs6000/rs6000.c ^ permalink raw reply [flat|nested] 6+ messages in thread
* [Bug target/60737] rs6000 expand_block_clear uses word stores on double word pointer 2014-04-02 4:35 [Bug middle-end/60737] New: rs6000 expand_block_clear uses word stores on double word pointer anton at samba dot org ` (3 preceding siblings ...) 2014-05-08 2:07 ` amodra at gcc dot gnu.org @ 2014-05-08 2:14 ` amodra at gmail dot com 4 siblings, 0 replies; 6+ messages in thread From: amodra at gmail dot com @ 2014-05-08 2:14 UTC (permalink / raw) To: gcc-bugs http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60737 Alan Modra <amodra at gmail dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution|--- |FIXED Target Milestone|--- |4.10.0 --- Comment #5 from Alan Modra <amodra at gmail dot com> --- Patch applied mainline. ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2014-05-08 2:14 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2014-04-02 4:35 [Bug middle-end/60737] New: rs6000 expand_block_clear uses word stores on double word pointer anton at samba dot org 2014-04-02 4:41 ` [Bug middle-end/60737] " anton at samba dot org 2014-04-02 8:39 ` rguenth at gcc dot gnu.org 2014-05-01 12:50 ` [Bug target/60737] " amodra at gmail dot com 2014-05-08 2:07 ` amodra at gcc dot gnu.org 2014-05-08 2:14 ` amodra at gmail dot com
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