On January 6, 2019 11:40:56 PM PST, Cao jin <caoj.f...@cn.fujitsu.com> wrote:
>According to objdump output of setup, function memset is not used in
>setup code. Currently, all usage of memset in setup come from macro
>definition of string.h.
>
>Signed-off-by: Cao jin <caoj.f...@cn.fujitsu.com>
>---
>Compiled and booted under x86_64; compiled under i386.
>
>Questions: now there is 2 definition of memcpy, one lies in copy.S,
>another lies in string.h which is mapped to gcc builtin function. Do we
>still need 2 definition? Could we move the content of copy.S to
>boot/string.c?
>
>At first glance, the usage of string.{c.h} of setup is kind of
>confusing,
>they are also used in compressed/ and purgatory/
>
> arch/x86/boot/copy.S | 15 ---------------
> 1 file changed, 15 deletions(-)
>
>diff --git a/arch/x86/boot/copy.S b/arch/x86/boot/copy.S
>index 15d9f74b0008..5157d08b0ff2 100644
>--- a/arch/x86/boot/copy.S
>+++ b/arch/x86/boot/copy.S
>@@ -33,21 +33,6 @@ GLOBAL(memcpy)
> retl
> ENDPROC(memcpy)
>
>-GLOBAL(memset)
>- pushw %di
>- movw %ax, %di
>- movzbl %dl, %eax
>- imull $0x01010101,%eax
>- pushw %cx
>- shrw $2, %cx
>- rep; stosl
>- popw %cx
>- andw $3, %cx
>- rep; stosb
>- popw %di
>- retl
>-ENDPROC(memset)
>-
> GLOBAL(copy_from_fs)
> pushw %ds
> pushw %fs
This is dependent on both gcc version and flags.
--
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