https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83651
--- Comment #6 from Arnd Bergmann <arnd at linaro dot org> --- Created attachment 43177 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43177&action=edit Single-file version of aes benchmark I've managed to condense the 'openssl speed aes-256-cbc' test into a single file now: $ x86_64-linux-gcc-7.2.1 -Wall -O2 aes_test.c -o aes_test $ time ./aes_test real 0m4.499s user 0m4.498s sys 0m0.000s $ x86_64-linux-gcc-7.2.1 -Wall -O2 aes_test.c -o aes_test -fno-code-hoisting $ time ./aes_test real 0m4.135s user 0m4.134s sys 0m0.000s The test is hardcoded to do 100000 runs of of 8192 bytes, so on my 3.1GHz CPU that translates cyles: $ echo $[4999 * 310000000 / 819200000] 1891 # 18.91 cycles $ echo $[4135 * 310000000 / 819200000] 1564 # 15.6 cycles Similar results with gcc-8.0.0: $ x86_64-linux-gcc-8.0.0 -Wall -O2 aes_test.c -o aes_test $ time ./aes_test real 0m4.471s user 0m4.470s sys 0m0.000s $ x86_64-linux-gcc-8.0.0 -Wall -O2 aes_test.c -o aes_test -fno-code-hoisting $ time ./aes_test real 0m4.052s user 0m4.052s sys 0m0.000s Hope that helps
