• Arnd Bergmann's avatar
    crypto: aes-generic - fix aes-generic regression on powerpc · 64def6f3
    Arnd Bergmann authored
    commit 6e36719f
    
     upstream.
    
    My last bugfix added -Os on the command line, which unfortunately caused
    a build regression on powerpc in some configurations.
    
    I've done some more analysis of the original problem and found slightly
    different workaround that avoids this regression and also results in
    better performance on gcc-7.0: -fcode-hoisting is an optimization step
    that got added in gcc-7 and that for all gcc-7 versions causes worse
    performance.
    
    This disables -fcode-hoisting on all compilers that understand the option.
    For gcc-7.1 and 7.2 I found the same performance as my previous patch
    (using -Os), in gcc-7.0 it was even better. On gcc-8 I could see no
    change in performance from this patch. In theory, code hoisting should
    not be able make things better for the AES cipher, so leaving it
    disabled for gcc-8 only serves to simplify the Makefile change.
    Reported-by: default avatarkbuild test robot <fengguang.wu@intel.com>
    Link: ht...
    64def6f3
Makefile 5.67 KB