[Bug rtl-optimization/61241] built-in memset makes the caller function slower than normal memset

[ma.jiang at zte dot com.cn]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61241

--- Comment #1 from ma.jiang at zte dot com.cn ---
Created attachment 32822
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=32822&action=edit
proposed patch