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/* Adapted from Linux: arch/x86/include/asm/paravirt.h */
/* { dg-do compile { target x86_64-pc-linux-gnu } } */
/* { dg-skip-if "" { *-*-* } { "-fno-fat-lto-objects" } { "" } } */
/* { dg-skip-if "" { *-*-* } { "-O0" } { "" } } */
/* Adapted/reduced from linux kernel (GPL-2.0). */
#include "../analyzer-decls.h"
typedef unsigned char u8;
typedef unsigned __INT32_TYPE__ u32;
typedef unsigned __INT64_TYPE__ u64;
typedef __SIZE_TYPE__ size_t;
#define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER)
#define __stringify_1(x...) #x
#define __stringify(x...) __stringify_1(x)
# define __ASM_FORM(x, ...) " " __stringify(x,##__VA_ARGS__) " "
# define __ASM_FORM_RAW(x, ...) __stringify(x,##__VA_ARGS__)
#ifndef __x86_64__
/* 32 bit */
# define __ASM_SEL(a,b) __ASM_FORM(a)
# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(a)
#else
/* 64 bit */
# define __ASM_SEL(a,b) __ASM_FORM(b)
# define __ASM_SEL_RAW(a,b) __ASM_FORM_RAW(b)
#endif
#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_SP __ASM_REG(sp)
register unsigned long current_stack_pointer asm(_ASM_SP);
#define ASM_CALL_CONSTRAINT "+r" (current_stack_pointer)
#define ANNOTATE_RETPOLINE_SAFE \
"999:\n\t" \
".pushsection .discard.retpoline_safe\n\t" \
_ASM_PTR " 999b\n\t" \
".popsection\n\t"
/* Adapted from Linux arch/x86/include/asm/paravirt.h */
/* snip */
/* ./arch/x86/include/asm/paravirt.h I think; was:
PVOP_VCALL4(cpu.cpuid, eax, ebx, ecx, edx);
*/
#ifndef __x86_64__
#define CLBR_ANY ((1 << 4) - 1)
#else
#define CLBR_ANY ((1 << 9) - 1)
#endif /* X86_64 */
struct pv_cpu_ops {
/* snip */
u64 (*read_msr_safe)(unsigned int msr, int *err);
/* snip */
};
struct paravirt_patch_template {
struct pv_cpu_ops cpu;
/* snip */
};
extern struct paravirt_patch_template pv_ops;
#define PARAVIRT_PATCH(x) \
(offsetof(struct paravirt_patch_template, x) / sizeof(void *))
#define paravirt_type(op) \
[paravirt_typenum] "i" (PARAVIRT_PATCH(op)), \
[paravirt_opptr] "i" (&(pv_ops.op))
#define paravirt_clobber(clobber) \
[paravirt_clobber] "i" (clobber)
/*
* Generate some code, and mark it as patchable by the
* apply_paravirt() alternate instruction patcher.
*/
#define _paravirt_alt(insn_string, type, clobber) \
"771:\n\t" insn_string "\n" "772:\n" \
".pushsection .parainstructions,\"a\"\n" \
_ASM_ALIGN "\n" \
_ASM_PTR " 771b\n" \
" .byte " type "\n" \
" .byte 772b-771b\n" \
" .short " clobber "\n" \
".popsection\n"
/* Generate patchable code, with the default asm parameters. */
#define paravirt_alt(insn_string) \
_paravirt_alt(insn_string, "%c[paravirt_typenum]", "%c[paravirt_clobber]")
#define PARAVIRT_CALL \
ANNOTATE_RETPOLINE_SAFE \
"call *%c[paravirt_opptr];"
#ifndef __x86_64__
/* 32-bit. */
#define PVOP_CALL_ARGS \
unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx;
#define PVOP_CALL_ARG1(x) "a" ((unsigned long)(x))
#define PVOP_CALL_ARG2(x) "d" ((unsigned long)(x))
#define PVOP_VCALL_CLOBBERS "=a" (__eax), "=d" (__edx), \
"=c" (__ecx)
#define PVOP_CALL_CLOBBERS PVOP_VCALL_CLOBBERS
#define PVOP_VCALLEE_CLOBBERS "=a" (__eax), "=d" (__edx)
#define PVOP_CALLEE_CLOBBERS PVOP_VCALLEE_CLOBBERS
#define EXTRA_CLOBBERS
#else
/* 64-bit. */
/* [re]ax isn't an arg, but the return val */
#define PVOP_CALL_ARGS \
unsigned long __edi = __edi, __esi = __esi, \
__edx = __edx, __ecx = __ecx, __eax = __eax;
#define PVOP_CALL_ARG1(x) "D" ((unsigned long)(x))
#define PVOP_CALL_ARG2(x) "S" ((unsigned long)(x))
#define PVOP_VCALL_CLOBBERS "=D" (__edi), \
"=S" (__esi), "=d" (__edx), \
"=c" (__ecx)
#define PVOP_CALL_CLOBBERS PVOP_VCALL_CLOBBERS, "=a" (__eax)
#define PVOP_VCALLEE_CLOBBERS "=a" (__eax)
#define PVOP_CALLEE_CLOBBERS PVOP_VCALLEE_CLOBBERS
#define EXTRA_CLOBBERS , "r8", "r9", "r10", "r11"
#endif /* CONFIG_X86_32 */
#define PVOP_TEST_NULL(op) ((void)pv_ops.op)
#define PVOP_RETVAL(rettype) \
({ unsigned long __mask = ~0UL; \
switch (sizeof(rettype)) { \
case 1: __mask = 0xffUL; break; \
case 2: __mask = 0xffffUL; break; \
case 4: __mask = 0xffffffffUL; break; \
default: break; \
} \
__mask & __eax; \
})
#define ____PVOP_CALL(ret, op, clbr, call_clbr, extra_clbr, ...) \
({ \
PVOP_CALL_ARGS; \
PVOP_TEST_NULL(op); \
asm volatile(paravirt_alt(PARAVIRT_CALL) \
: call_clbr, ASM_CALL_CONSTRAINT \
: paravirt_type(op), \
paravirt_clobber(clbr), \
##__VA_ARGS__ \
: "memory", "cc" extra_clbr); \
ret; \
})
#define __PVOP_CALL(rettype, op, ...) \
____PVOP_CALL(PVOP_RETVAL(rettype), op, CLBR_ANY, \
PVOP_CALL_CLOBBERS, EXTRA_CLOBBERS, ##__VA_ARGS__)
#define PVOP_CALL2(rettype, op, arg1, arg2) \
__PVOP_CALL(rettype, op, PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2))
static inline u64 paravirt_read_msr_safe(unsigned msr, int *err)
{
return PVOP_CALL2(u64, cpu.read_msr_safe, msr, err);
}
#define rdmsr_safe(msr, a, b) \
({ \
int _err; \
u64 _l = paravirt_read_msr_safe(msr, &_err); \
(*a) = (u32)_l; \
(*b) = _l >> 32; \
_err; \
})
void check_init_int(int);
void check_init_u32(u32);
void test(void)
{
int err;
u32 eax, edx;
err = rdmsr_safe(0, &eax, &edx);
check_init_int(err);
check_init_u32(eax);
check_init_u32(edx);
}
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