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Peter Anvin" , x86@kernel.org, Ard Biesheuvel , Bill Metzenthen , Brijesh Singh , Joerg Roedel , Josh Poimboeuf , "Kirill A. Shutemov" , Mark Rutland , Michael Roth , Peter Zijlstra , Sean Christopherson , Steven Rostedt , Ammar Faizi , GNU/Weeb Mailing List , Linux Kernel Mailing List Subject: Re: [PATCH 1/1] x86: Change mov $0, %reg with xor %reg, %reg Message-ID: References: <20220804152656.8840-1-knscarlet@gnuweeb.org> <20220804152656.8840-2-knscarlet@gnuweeb.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20220804152656.8840-2-knscarlet@gnuweeb.org> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 04, 2022 at 03:26:55PM +0000, Kanna Scarlet wrote: > Change mov $0, %reg with xor %reg, %reg because xor %reg, %reg is > smaller so it is good to save space Bonus points if you find out what other advantage XOR reg,reg has when it comes to clearing integer registers. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette