https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95134
H.J. Lu <hjl.tools at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Resolution|WONTFIX |---
Status|RESOLVED |NEW
Assignee|unassigned at gcc dot gnu.org |hjl.tools at gmail dot
com
--- Comment #5 from H.J. Lu <hjl.tools at gmail dot com> ---
Created attachment 48538
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48538&action=edit
A patch to add -mavoid-libcall
The -mgeneral-regs-only option generates code that uses only the
general-purpose registers. It prevents the compiler from using vector
registers. But GCC may still generate calls to memcpy, memmove, memset
and memcmp library functions. In the GNU C library, these library
functions are implementated with vector registers, which makes the
-mgeneral-regs-only option less effective. The new -mavoid-libcall
option expands memcpy, memmove and memset into REP MOVSB and REP STOSB
sequence. This option can be further enhanced with a cmpmem pattern
to expand memcmp into REP CMPSB sequence in the future.
