From f87bc8dc7a7c438c70f97b4e51c76a183313272e Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin (Intel)" Date: Fri, 10 Sep 2021 12:59:09 -0700 Subject: [PATCH] x86/asm: Add _ASM_RIP() macro for x86-64 (%rip) suffix Add a macro _ASM_RIP() to add a (%rip) suffix on 64 bits only. This is useful for immediate memory references where one doesn't want gcc to possibly use a register indirection as it may in the case of an "m" constraint. Signed-off-by: H. Peter Anvin (Intel) Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/20210910195910.2542662-3-hpa@zytor.com --- arch/x86/include/asm/asm.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h index 3ad3da9a7d974..c5a19ccda0fe7 100644 --- a/arch/x86/include/asm/asm.h +++ b/arch/x86/include/asm/asm.h @@ -6,11 +6,13 @@ # define __ASM_FORM(x, ...) x,## __VA_ARGS__ # define __ASM_FORM_RAW(x, ...) x,## __VA_ARGS__ # define __ASM_FORM_COMMA(x, ...) x,## __VA_ARGS__, +# define __ASM_REGPFX % #else #include # define __ASM_FORM(x, ...) " " __stringify(x,##__VA_ARGS__) " " # define __ASM_FORM_RAW(x, ...) __stringify(x,##__VA_ARGS__) # define __ASM_FORM_COMMA(x, ...) " " __stringify(x,##__VA_ARGS__) "," +# define __ASM_REGPFX %% #endif #define _ASM_BYTES(x, ...) __ASM_FORM(.byte x,##__VA_ARGS__ ;) @@ -49,6 +51,9 @@ #define _ASM_SI __ASM_REG(si) #define _ASM_DI __ASM_REG(di) +/* Adds a (%rip) suffix on 64 bits only; for immediate memory references */ +#define _ASM_RIP(x) __ASM_SEL_RAW(x, x (__ASM_REGPFX rip)) + #ifndef __x86_64__ /* 32 bit */ -- 2.30.2