From 2f576a65a09d98e63e548143825d7a33fa5cff1b Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Thu, 7 Apr 2022 08:34:58 +0200 Subject: [PATCH] x86/boot: fold branches in video handling code MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Using Jcc to branch around a JMP is necessary only in pre-386 code, where Jcc is limited to disp8. Use the opposite Jcc directly in two places. Since it's adjacent, also convert an ORB to TESTB. Signed-off-by: Jan Beulich Reviewed-by: Roger Pau Monné --- xen/arch/x86/boot/video.S | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/xen/arch/x86/boot/video.S b/xen/arch/x86/boot/video.S index 822d6d9cf1..b5af93dbc5 100644 --- a/xen/arch/x86/boot/video.S +++ b/xen/arch/x86/boot/video.S @@ -332,8 +332,7 @@ lment: movb $0, (%di) cmpw $0x656d, (%si) # 'me' jnz lmhx cmpw $0x756e, 2(%si) # 'nu' - jnz lmhx - jmp listm + jz listm lmhx: xorw %bx, %bx # Else => mode ID in hex lmhex: lodsb @@ -401,10 +400,8 @@ mode_set: cmpb $VIDEO_FIRST_VESA>>8, %ah jnc check_vesa - orb %ah, %ah - jnz setbad - - jmp setmenu + testb %ah, %ah + jz setmenu setbad: clc ret -- 2.30.2