From: Paolo Bonzini Date: Thu, 27 Mar 2014 10:36:25 +0000 (+0100) Subject: KVM: emulate: speed up emulated moves X-Git-Tag: omap-for-v3.17/fixes-against-rc2~184^2~37 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=54cfdb3e95d4f70409a7d3432a42cffc9a232be7;p=pandora-kernel.git KVM: emulate: speed up emulated moves We can just blindly move all 16 bytes of ctxt->src's value to ctxt->dst. write_register_operand will take care of writing only the lower bytes. Avoiding a call to memcpy (the compiler optimizes it out) gains about 200 cycles on kvm-unit-tests for register-to-register moves, and makes them about as fast as arithmetic instructions. We could perhaps get a larger speedup by moving all instructions _except_ moves out of x86_emulate_insn, removing opcode_len, and replacing the switch statement with an inlined em_mov. Signed-off-by: Paolo Bonzini --- Reading git-diff-tree failed