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charset="utf-8" Replace (mainly) MOV forms with shorter insns (or sequences thereof). Signed-off-by: Jan Beulich --- Of course there's more room for improvement. For example there look to be a number of LEAs which really could be MOVs. --- a/xen/arch/x86/boot/video.S +++ b/xen/arch/x86/boot/video.S @@ -121,8 +121,7 @@ mopar_gr: movw %ax, _param(PARAM_LFB_WIDTH) movw 20(%di), %ax movw %ax, _param(PARAM_LFB_HEIGHT) - movb 25(%di), %al - movb $0, %ah + movzbw 25(%di), %ax movw %ax, _param(PARAM_LFB_DEPTH) movl 40(%di), %eax movl %eax, _param(PARAM_LFB_BASE) @@ -135,8 +134,7 @@ mopar_gr: =20 # get video mem size leaw vesa_glob_info, %di - xorl %eax, %eax - movw 18(%di), %ax + movzwl 18(%di), %eax movl %eax, _param(PARAM_LFB_SIZE) =20 # store mode capabilities @@ -144,14 +142,11 @@ mopar_gr: movl %eax, _param(PARAM_CAPABILITIES) =20 # switching the DAC to 8-bit is for <=3D 8 bpp only - movw _param(PARAM_LFB_DEPTH), %ax - cmpw $8, %ax + cmpw $8, _param(PARAM_LFB_DEPTH) jg dac_done =20 # get DAC switching capability - xorl %eax, %eax - movb 10(%di), %al - testb $1, %al + testb $1, 10(%di) jz dac_set =20 # attempt to switch DAC to 8-bit @@ -164,17 +159,17 @@ mopar_gr: =20 dac_set: # set color size to DAC size - movb bootsym(dac_size), %al + movzbw bootsym(dac_size), %ax movb %al, _param(PARAM_LFB_COLORS+0) movb %al, _param(PARAM_LFB_COLORS+2) movb %al, _param(PARAM_LFB_COLORS+4) movb %al, _param(PARAM_LFB_COLORS+6) =20 # set color offsets to 0 - movb $0, _param(PARAM_LFB_COLORS+1) - movb $0, _param(PARAM_LFB_COLORS+3) - movb $0, _param(PARAM_LFB_COLORS+5) - movb $0, _param(PARAM_LFB_COLORS+7) + movb %ah, _param(PARAM_LFB_COLORS+1) + movb %ah, _param(PARAM_LFB_COLORS+3) + movb %ah, _param(PARAM_LFB_COLORS+5) + movb %ah, _param(PARAM_LFB_COLORS+7) =20 dac_done: # get protected mode interface information @@ -504,7 +499,8 @@ setvesabysize: call mode_table leaw modelist,%si 1: add $8,%si - cmpw $ASK_VGA,-8(%si) # End? + movw -8(%si),%bx + cmpw $ASK_VGA,%bx # End? je setbad movw -6(%si),%ax cmpw %ax,bootsym(vesa_size)+0 @@ -515,9 +511,7 @@ setvesabysize: movw -2(%si),%ax cmpw %ax,bootsym(vesa_size)+4 jne 1b - movw -8(%si),%ax - movw %ax,%bx - movw %ax,bootsym(boot_vid_mode) + movw %bx,bootsym(boot_vid_mode) jmp check_vesa =20 # Table of routines for setting of the special modes. @@ -773,8 +767,7 @@ vesa2: pushw %cx movw %bx, 2(%di) movw 0x14(%di), %bx # Height movw %bx, 4(%di) - xorw %bx, %bx - movb 0x19(%di), %bl # Depth + movzbw 0x19(%di), %bx # Depth movw %bx, 6(%di) =20 addw $8, %di # The mode is valid. Store it. @@ -901,8 +894,7 @@ gettime: movb %dh, %al # %dh contains the seconds andb $0x0f, %al movb %dh, %ah - movb $0x04, %cl - shrb %cl, %ah + shrb $4, %ah aad popw %cx ret @@ -959,8 +951,8 @@ store_edid: .Lforce_edid: movw $0x4f15, %ax # do VBE/DDC movw $0x01, %bx - movw $0x00, %cx - movw $0x00, %dx + xorw %cx, %cx + xorw %dx, %dx movw $bootsym(boot_edid_info), %di int $0x10 =20