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* [Bug c/61473] New: register sized memmove not inlined @ 2014-06-11 12:23 jtaylor.debian at googlemail dot com 2014-06-11 12:24 ` [Bug c/61473] " jtaylor.debian at googlemail dot com ` (3 more replies) 0 siblings, 4 replies; 5+ messages in thread From: jtaylor.debian at googlemail dot com @ 2014-06-11 12:23 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61473 Bug ID: 61473 Summary: register sized memmove not inlined Product: gcc Version: 4.10.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: jtaylor.debian at googlemail dot com in this example file compiled with gcc-4.10 -O3 inlines the memcpy, but not the memmove: #include <string.h> void a(int *a, int *b) { memcpy(a, b, sizeof(*a)); } void b(int *a, int *b) { memmove(a, b, sizeof(*a)); } at least on x86 the integer can be stored in fully in a register and saved back to arbitrary aligned memory, so it should not matter if the two address overlap and gcc should be able to replace it with a much faster inline memcpy. Currently gcc only inlines the memmove for 1 byte types. I am using a recent svn copy of gcc: $ gcc-4.10 --version gcc (GCC) 4.10.0 20140605 (experimental) ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug c/61473] register sized memmove not inlined 2014-06-11 12:23 [Bug c/61473] New: register sized memmove not inlined jtaylor.debian at googlemail dot com @ 2014-06-11 12:24 ` jtaylor.debian at googlemail dot com 2014-06-12 9:26 ` [Bug middle-end/61473] " rguenth at gcc dot gnu.org ` (2 subsequent siblings) 3 siblings, 0 replies; 5+ messages in thread From: jtaylor.debian at googlemail dot com @ 2014-06-11 12:24 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61473 --- Comment #1 from Julian Taylor <jtaylor.debian at googlemail dot com> --- I am using glibc 2.19-0ubuntu6 from the ubuntu 14.04 trusty repository ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/61473] register sized memmove not inlined 2014-06-11 12:23 [Bug c/61473] New: register sized memmove not inlined jtaylor.debian at googlemail dot com 2014-06-11 12:24 ` [Bug c/61473] " jtaylor.debian at googlemail dot com @ 2014-06-12 9:26 ` rguenth at gcc dot gnu.org 2014-07-11 13:43 ` rguenth at gcc dot gnu.org 2014-07-11 13:44 ` rguenth at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: rguenth at gcc dot gnu.org @ 2014-06-12 9:26 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61473 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |ASSIGNED Last reconfirmed| |2014-06-12 Component|c |middle-end Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot gnu.org Ever confirmed|0 |1 --- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- The transform is simply not implemented for memmove but simplification always goes through memmove -> memcpy and then applies this optimization to memcpy. But of course here the memmove -> memcpy transform is not valid. ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/61473] register sized memmove not inlined 2014-06-11 12:23 [Bug c/61473] New: register sized memmove not inlined jtaylor.debian at googlemail dot com 2014-06-11 12:24 ` [Bug c/61473] " jtaylor.debian at googlemail dot com 2014-06-12 9:26 ` [Bug middle-end/61473] " rguenth at gcc dot gnu.org @ 2014-07-11 13:43 ` rguenth at gcc dot gnu.org 2014-07-11 13:44 ` rguenth at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: rguenth at gcc dot gnu.org @ 2014-07-11 13:43 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61473 --- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> --- Author: rguenth Date: Fri Jul 11 13:42:55 2014 New Revision: 212452 URL: https://gcc.gnu.org/viewcvs?rev=212452&root=gcc&view=rev Log: 2014-07-11 Richard Biener <rguenther@suse.de> PR middle-end/61473 * builtins.c (fold_builtin_memory_op): Inline memory moves that can be implemented with a single load followed by a single store. (c_strlen): Only warn when only_value is not 2. * gcc.dg/memmove-4.c: New testcase. * gcc.dg/strlenopt-8.c: XFAIL. * gfortran.dg/coarray_lib_realloc_1.f90: Adjust. Added: trunk/gcc/testsuite/gcc.dg/memmove-4.c Modified: trunk/gcc/ChangeLog trunk/gcc/builtins.c trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gcc.dg/strlenopt-8.c trunk/gcc/testsuite/gfortran.dg/coarray_lib_realloc_1.f90 ^ permalink raw reply [flat|nested] 5+ messages in thread
* [Bug middle-end/61473] register sized memmove not inlined 2014-06-11 12:23 [Bug c/61473] New: register sized memmove not inlined jtaylor.debian at googlemail dot com ` (2 preceding siblings ...) 2014-07-11 13:43 ` rguenth at gcc dot gnu.org @ 2014-07-11 13:44 ` rguenth at gcc dot gnu.org 3 siblings, 0 replies; 5+ messages in thread From: rguenth at gcc dot gnu.org @ 2014-07-11 13:44 UTC (permalink / raw) To: gcc-bugs https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61473 Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|ASSIGNED |RESOLVED Resolution|--- |FIXED --- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> --- Fixed. ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2014-07-11 13:44 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2014-06-11 12:23 [Bug c/61473] New: register sized memmove not inlined jtaylor.debian at googlemail dot com 2014-06-11 12:24 ` [Bug c/61473] " jtaylor.debian at googlemail dot com 2014-06-12 9:26 ` [Bug middle-end/61473] " rguenth at gcc dot gnu.org 2014-07-11 13:43 ` rguenth at gcc dot gnu.org 2014-07-11 13:44 ` rguenth at gcc dot gnu.org
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