linux/arch/x86/include/asm/asm.h
H. Peter Anvin ff3554b409 x86, asm: define CC_SET() and CC_OUT() macros
The CC_SET() and CC_OUT() macros can be used together to take
advantage of the new __GCC_ASM_FLAG_OUTPUTS__ feature in gcc 6+ while
remaining backwards compatible.  CC_SET() generates a SET instruction
on older compilers; CC_OUT() makes sure the output is received in the
correct variable.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1465414726-197858-5-git-send-email-hpa@linux.intel.com
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-06-08 12:41:20 -07:00

129 lines
3.2 KiB
C

#ifndef _ASM_X86_ASM_H
#define _ASM_X86_ASM_H
#ifdef __ASSEMBLY__
# define __ASM_FORM(x) x
# define __ASM_FORM_RAW(x) x
# define __ASM_FORM_COMMA(x) x,
#else
# define __ASM_FORM(x) " " #x " "
# define __ASM_FORM_RAW(x) #x
# define __ASM_FORM_COMMA(x) " " #x ","
#endif
#ifdef CONFIG_X86_32
# define __ASM_SEL(a,b) __ASM_FORM(a)
# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a)
#else
# define __ASM_SEL(a,b) __ASM_FORM(b)
# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b)
#endif
#define __ASM_SIZE(inst, ...) __ASM_SEL(inst##l##__VA_ARGS__, \
inst##q##__VA_ARGS__)
#define __ASM_REG(reg) __ASM_SEL_RAW(e##reg, r##reg)
#define _ASM_PTR __ASM_SEL(.long, .quad)
#define _ASM_ALIGN __ASM_SEL(.balign 4, .balign 8)
#define _ASM_MOV __ASM_SIZE(mov)
#define _ASM_INC __ASM_SIZE(inc)
#define _ASM_DEC __ASM_SIZE(dec)
#define _ASM_ADD __ASM_SIZE(add)
#define _ASM_SUB __ASM_SIZE(sub)
#define _ASM_XADD __ASM_SIZE(xadd)
#define _ASM_AX __ASM_REG(ax)
#define _ASM_BX __ASM_REG(bx)
#define _ASM_CX __ASM_REG(cx)
#define _ASM_DX __ASM_REG(dx)
#define _ASM_SP __ASM_REG(sp)
#define _ASM_BP __ASM_REG(bp)
#define _ASM_SI __ASM_REG(si)
#define _ASM_DI __ASM_REG(di)
/*
* Macros to generate condition code outputs from inline assembly,
* The output operand must be type "bool".
*/
#ifdef __GCC_ASM_FLAG_OUTPUTS__
# define CC_SET(c) "\n\t/* output condition code " #c "*/\n"
# define CC_OUT(c) "=@cc" #c
#else
# define CC_SET(c) "\n\tset" #c " %[_cc_" #c "]\n"
# define CC_OUT(c) [_cc_ ## c] "=qm"
#endif
/* Exception table entry */
#ifdef __ASSEMBLY__
# define _ASM_EXTABLE_HANDLE(from, to, handler) \
.pushsection "__ex_table","a" ; \
.balign 4 ; \
.long (from) - . ; \
.long (to) - . ; \
.long (handler) - . ; \
.popsection
# define _ASM_EXTABLE(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
# define _ASM_EXTABLE_FAULT(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
# define _ASM_EXTABLE_EX(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
# define _ASM_NOKPROBE(entry) \
.pushsection "_kprobe_blacklist","aw" ; \
_ASM_ALIGN ; \
_ASM_PTR (entry); \
.popsection
.macro ALIGN_DESTINATION
/* check for bad alignment of destination */
movl %edi,%ecx
andl $7,%ecx
jz 102f /* already aligned */
subl $8,%ecx
negl %ecx
subl %ecx,%edx
100: movb (%rsi),%al
101: movb %al,(%rdi)
incq %rsi
incq %rdi
decl %ecx
jnz 100b
102:
.section .fixup,"ax"
103: addl %ecx,%edx /* ecx is zerorest also */
jmp copy_user_handle_tail
.previous
_ASM_EXTABLE(100b,103b)
_ASM_EXTABLE(101b,103b)
.endm
#else
# define _EXPAND_EXTABLE_HANDLE(x) #x
# define _ASM_EXTABLE_HANDLE(from, to, handler) \
" .pushsection \"__ex_table\",\"a\"\n" \
" .balign 4\n" \
" .long (" #from ") - .\n" \
" .long (" #to ") - .\n" \
" .long (" _EXPAND_EXTABLE_HANDLE(handler) ") - .\n" \
" .popsection\n"
# define _ASM_EXTABLE(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_default)
# define _ASM_EXTABLE_FAULT(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)
# define _ASM_EXTABLE_EX(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
/* For C file, we already have NOKPROBE_SYMBOL macro */
#endif
#endif /* _ASM_X86_ASM_H */