/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
/*
* Author: Paul Burton <paul.burton@mips.com>
* (C) Copyright 2018 MIPS Tech LLC
*
* Based on rseq-arm.h:
* (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*/
/*
* RSEQ_SIG uses the break instruction. The instruction pattern is:
*
* On MIPS:
* 0350000d break 0x350
*
* On nanoMIPS:
* 00100350 break 0x350
*
* On microMIPS:
* 0000d407 break 0x350
*
* For nanoMIPS32 and microMIPS, the instruction stream is encoded as 16-bit
* halfwords, so the signature halfwords need to be swapped accordingly for
* little-endian.
*/
#if defined(__nanomips__)
# ifdef __MIPSEL__
# define RSEQ_SIG 0x03500010
# else
# define RSEQ_SIG 0x00100350
# endif
#elif defined(__mips_micromips)
# ifdef __MIPSEL__
# define RSEQ_SIG 0xd4070000
# else
# define RSEQ_SIG 0x0000d407
# endif
#elif defined(__mips__)
# define RSEQ_SIG 0x0350000d
#else
/* Unknown MIPS architecture. */
#endif
#define rseq_smp_mb() __asm__ __volatile__ ("sync" ::: "memory")
#define rseq_smp_rmb() rseq_smp_mb()
#define rseq_smp_wmb() rseq_smp_mb()
#define rseq_smp_load_acquire(p) \
__extension__ ({ \
__typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \
rseq_smp_mb(); \
____p1; \
})
#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb()
#define rseq_smp_store_release(p, v) \
do { \
rseq_smp_mb(); \
RSEQ_WRITE_ONCE(*p, v); \
} while (0)
#ifdef RSEQ_SKIP_FASTPATH
#include "rseq-skip.h"
#else /* !RSEQ_SKIP_FASTPATH */
#if _MIPS_SZLONG == 64
# define LONG ".dword"
# define LONG_LA "dla"
# define LONG_L "ld"
# define LONG_S "sd"
# define LONG_ADDI "daddiu"
# define U32_U64_PAD(x) x
#elif _MIPS_SZLONG == 32
# define LONG ".word"
# define LONG_LA "la"
# define LONG_L "lw"
# define LONG_S "sw"
# define LONG_ADDI "addiu"
# ifdef __BIG_ENDIAN
# define U32_U64_PAD(x) "0x0, " x
# else
# define U32_U64_PAD(x) x ", 0x0"
# endif
#else
# error unsupported _MIPS_SZLONG
#endif
#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip, \
post_commit_offset, abort_ip) \
".pushsection __rseq_cs, \"aw\"\n\t" \
".balign 32\n\t" \
__rseq_str(label) ":\n\t" \
".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \
LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \
".popsection\n\t" \
".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \
LONG " " U32_U64_PAD(__rseq_str(label) "b") "\n\t" \
".popsection\n\t"
#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \
__RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \
(post_commit_ip - start_ip), abort_ip)
/*
* Exit points of a rseq critical section consist of all instructions outside
* of the critical section where a critical section can either branch to or
* reach through the normal course of its execution. The abort IP and the
* post-commit IP are already part of the __rseq_cs section and should not be
* explicitly defined as additional exit points. Knowing all exit points is
* useful to assist debuggers stepping over the critical section.
*/
#define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \
".pushsection __rseq_exit_point_array, \"aw\"\n\t" \
LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
LONG " " U32_U64_PAD(__rseq_str(exit_ip)) "\n\t" \
".popsection\n\t"
#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \
RSEQ_INJECT_ASM(1) \
LONG_LA " $4, " __rseq_str(cs_label) "\n\t" \
LONG_S " $4, %[" __rseq_str(rseq_cs) "]\n\t" \
__rseq_str(label) ":\n\t"
#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \
RSEQ_INJECT_ASM(2) \
"lw $4, %[" __rseq_str(current_cpu_id) "]\n\t" \
"bne $4, %[" __rseq_str(cpu_id) "], " __rseq_str(label) "\n\t"
#define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \
abort_label, version, flags, \
start_ip, post_commit_offset, abort_ip) \
".balign 32\n\t" \
__rseq_str(table_label) ":\n\t" \
".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \
LONG " " U32_U64_PAD(__rseq_str(start_ip)) "\n\t" \
LONG " " U32_U64_PAD(__rseq_str(post_commit_offset)) "\n\t" \
LONG " " U32_U64_PAD(__rseq_str(abort_ip)) "\n\t" \
".word " __rseq_str(RSEQ_SIG) "\n\t" \
__rseq_str(label) ":\n\t" \
teardown \
"b %l[" __rseq_str(abort_label) "]\n\t"
#define RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, abort_label, \
start_ip, post_commit_ip, abort_ip) \
__RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \
abort_label, 0x0, 0x0, start_ip, \
(post_commit_ip - start_ip), abort_ip)
#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \
__rseq_str(label) ":\n\t" \
teardown \
"b %l[" __rseq_str(cmpfail_label) "]\n\t"
#define rseq_workaround_gcc_asm_size_guess() __asm__ __volatile__("")
static inline __attribute__((always_inline))
int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
{
RSEQ_INJECT_C(9)
rseq_workaround_gcc_asm_size_guess();
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
#endif
/* Start rseq by storing table entry pointer into rseq_cs. */
RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
RSEQ_INJECT_ASM(3)
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], %l[error2]\n\t"
#endif
/* final store */
LONG_S " %[newv], %[v]\n\t"
"2:\n\t"
RSEQ_INJECT_ASM(5)
"b 5f\n\t"
RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
"5:\n\t"
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
[current_cpu_id] "m" (__rseq_abi.cpu_id),
[rseq_cs] "m" (__rseq_abi.rseq_cs),
[v] "m" (*v),
[expect] "r" (expect),
[newv] "r" (newv)
RSEQ_INJECT_INPUT
: "$4", "memory"
RSEQ_INJECT_CLOBBER
: abort, cmpfail
#ifdef RSEQ_COMPARE_TWICE
, error1, error2
#endif
);
rseq_workaround_gcc_asm_size_guess();
return 0;
abort:
rseq_workaround_gcc_asm_size_guess();
RSEQ_INJECT_FAILED
return -1;
cmpfail:
rseq_workaround_gcc_asm_size_guess();
return 1;
#ifdef RSEQ_COMPARE_TWICE
error1:
rseq_bug("cpu_id comparison failed");
error2:
rseq_bug("expected value comparison failed");
#endif
}
static inline __attribute__((always_inline))
int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
off_t voffp, intptr_t *load, int cpu)
{
RSEQ_INJECT_C(9)
rseq_workaround_gcc_asm_size_guess();
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
#endif
/* Start rseq by storing table entry pointer into rseq_cs. */
RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
RSEQ_INJECT_ASM(3)
LONG_L " $4, %[v]\n\t"
"beq $4, %[expectnot], %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
LONG_L " $4, %[v]\n\t"
"beq $4, %[expectnot], %l[error2]\n\t"
#endif
LONG_S " $4, %[load]\n\t"
LONG_ADDI " $4, %[voffp]\n\t"
LONG_L " $4, 0($4)\n\t"
/* final store */
LONG_S " $4, %[v]\n\t"
"2:\n\t"
RSEQ_INJECT_ASM(5)
"b 5f\n\t"
RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
"5:\n\t"
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
[current_cpu_id] "m" (__rseq_abi.cpu_id),
[rseq_cs] "m" (__rseq_abi.rseq_cs),
/* final store input */
[v] "m" (*v),
[expectnot] "r" (expectnot),
[voffp] "Ir" (voffp),
[load] "m" (*load)
RSEQ_INJECT_INPUT
: "$4", "memory"
RSEQ_INJECT_CLOBBER
: abort, cmpfail
#ifdef RSEQ_COMPARE_TWICE
, error1, error2
#endif
);
rseq_workaround_gcc_asm_size_guess();
return 0;
abort:
rseq_workaround_gcc_asm_size_guess();
RSEQ_INJECT_FAILED
return -1;
cmpfail:
rseq_workaround_gcc_asm_size_guess();
return 1;
#ifdef RSEQ_COMPARE_TWICE
error1:
rseq_bug("cpu_id comparison failed");
error2:
rseq_bug("expected value comparison failed");
#endif
}
static inline __attribute__((always_inline))
int rseq_addv(intptr_t *v, intptr_t count, int cpu)
{
RSEQ_INJECT_C(9)
rseq_workaround_gcc_asm_size_guess();
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
#endif
/* Start rseq by storing table entry pointer into rseq_cs. */
RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
RSEQ_INJECT_ASM(3)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
#endif
LONG_L " $4, %[v]\n\t"
LONG_ADDI " $4, %[count]\n\t"
/* final store */
LONG_S " $4, %[v]\n\t"
"2:\n\t"
RSEQ_INJECT_ASM(4)
"b 5f\n\t"
RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
"5:\n\t"
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
[current_cpu_id] "m" (__rseq_abi.cpu_id),
[rseq_cs] "m" (__rseq_abi.rseq_cs),
[v] "m" (*v),
[count] "Ir" (count)
RSEQ_INJECT_INPUT
: "$4", "memory"
RSEQ_INJECT_CLOBBER
: abort
#ifdef RSEQ_COMPARE_TWICE
, error1
#endif
);
rseq_workaround_gcc_asm_size_guess();
return 0;
abort:
rseq_workaround_gcc_asm_size_guess();
RSEQ_INJECT_FAILED
return -1;
#ifdef RSEQ_COMPARE_TWICE
error1:
rseq_bug("cpu_id comparison failed");
#endif
}
static inline __attribute__((always_inline))
int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
intptr_t *v2, intptr_t newv2,
intptr_t newv, int cpu)
{
RSEQ_INJECT_C(9)
rseq_workaround_gcc_asm_size_guess();
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
#endif
/* Start rseq by storing table entry pointer into rseq_cs. */
RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
RSEQ_INJECT_ASM(3)
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], %l[error2]\n\t"
#endif
/* try store */
LONG_S " %[newv2], %[v2]\n\t"
RSEQ_INJECT_ASM(5)
/* final store */
LONG_S " %[newv], %[v]\n\t"
"2:\n\t"
RSEQ_INJECT_ASM(6)
"b 5f\n\t"
RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
"5:\n\t"
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
[current_cpu_id] "m" (__rseq_abi.cpu_id),
[rseq_cs] "m" (__rseq_abi.rseq_cs),
/* try store input */
[v2] "m" (*v2),
[newv2] "r" (newv2),
/* final store input */
[v] "m" (*v),
[expect] "r" (expect),
[newv] "r" (newv)
RSEQ_INJECT_INPUT
: "$4", "memory"
RSEQ_INJECT_CLOBBER
: abort, cmpfail
#ifdef RSEQ_COMPARE_TWICE
, error1, error2
#endif
);
rseq_workaround_gcc_asm_size_guess();
return 0;
abort:
rseq_workaround_gcc_asm_size_guess();
RSEQ_INJECT_FAILED
return -1;
cmpfail:
rseq_workaround_gcc_asm_size_guess();
return 1;
#ifdef RSEQ_COMPARE_TWICE
error1:
rseq_bug("cpu_id comparison failed");
error2:
rseq_bug("expected value comparison failed");
#endif
}
static inline __attribute__((always_inline))
int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
intptr_t *v2, intptr_t newv2,
intptr_t newv, int cpu)
{
RSEQ_INJECT_C(9)
rseq_workaround_gcc_asm_size_guess();
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
#endif
/* Start rseq by storing table entry pointer into rseq_cs. */
RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
RSEQ_INJECT_ASM(3)
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], %l[error2]\n\t"
#endif
/* try store */
LONG_S " %[newv2], %[v2]\n\t"
RSEQ_INJECT_ASM(5)
"sync\n\t" /* full sync provides store-release */
/* final store */
LONG_S " %[newv], %[v]\n\t"
"2:\n\t"
RSEQ_INJECT_ASM(6)
"b 5f\n\t"
RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
"5:\n\t"
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
[current_cpu_id] "m" (__rseq_abi.cpu_id),
[rseq_cs] "m" (__rseq_abi.rseq_cs),
/* try store input */
[v2] "m" (*v2),
[newv2] "r" (newv2),
/* final store input */
[v] "m" (*v),
[expect] "r" (expect),
[newv] "r" (newv)
RSEQ_INJECT_INPUT
: "$4", "memory"
RSEQ_INJECT_CLOBBER
: abort, cmpfail
#ifdef RSEQ_COMPARE_TWICE
, error1, error2
#endif
);
rseq_workaround_gcc_asm_size_guess();
return 0;
abort:
rseq_workaround_gcc_asm_size_guess();
RSEQ_INJECT_FAILED
return -1;
cmpfail:
rseq_workaround_gcc_asm_size_guess();
return 1;
#ifdef RSEQ_COMPARE_TWICE
error1:
rseq_bug("cpu_id comparison failed");
error2:
rseq_bug("expected value comparison failed");
#endif
}
static inline __attribute__((always_inline))
int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
intptr_t *v2, intptr_t expect2,
intptr_t newv, int cpu)
{
RSEQ_INJECT_C(9)
rseq_workaround_gcc_asm_size_guess();
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error3])
#endif
/* Start rseq by storing table entry pointer into rseq_cs. */
RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
RSEQ_INJECT_ASM(3)
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(4)
LONG_L " $4, %[v2]\n\t"
"bne $4, %[expect2], %l[cmpfail]\n\t"
RSEQ_INJECT_ASM(5)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1])
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], %l[error2]\n\t"
LONG_L " $4, %[v2]\n\t"
"bne $4, %[expect2], %l[error3]\n\t"
#endif
/* final store */
LONG_S " %[newv], %[v]\n\t"
"2:\n\t"
RSEQ_INJECT_ASM(6)
"b 5f\n\t"
RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f)
"5:\n\t"
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
[current_cpu_id] "m" (__rseq_abi.cpu_id),
[rseq_cs] "m" (__rseq_abi.rseq_cs),
/* cmp2 input */
[v2] "m" (*v2),
[expect2] "r" (expect2),
/* final store input */
[v] "m" (*v),
[expect] "r" (expect),
[newv] "r" (newv)
RSEQ_INJECT_INPUT
: "$4", "memory"
RSEQ_INJECT_CLOBBER
: abort, cmpfail
#ifdef RSEQ_COMPARE_TWICE
, error1, error2, error3
#endif
);
rseq_workaround_gcc_asm_size_guess();
return 0;
abort:
rseq_workaround_gcc_asm_size_guess();
RSEQ_INJECT_FAILED
return -1;
cmpfail:
rseq_workaround_gcc_asm_size_guess();
return 1;
#ifdef RSEQ_COMPARE_TWICE
error1:
rseq_bug("cpu_id comparison failed");
error2:
rseq_bug("1st expected value comparison failed");
error3:
rseq_bug("2nd expected value comparison failed");
#endif
}
static inline __attribute__((always_inline))
int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
void *dst, void *src, size_t len,
intptr_t newv, int cpu)
{
uintptr_t rseq_scratch[3];
RSEQ_INJECT_C(9)
rseq_workaround_gcc_asm_size_guess();
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
#endif
LONG_S " %[src], %[rseq_scratch0]\n\t"
LONG_S " %[dst], %[rseq_scratch1]\n\t"
LONG_S " %[len], %[rseq_scratch2]\n\t"
/* Start rseq by storing table entry pointer into rseq_cs. */
RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
RSEQ_INJECT_ASM(3)
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], 5f\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], 7f\n\t"
#endif
/* try memcpy */
"beqz %[len], 333f\n\t" \
"222:\n\t" \
"lb $4, 0(%[src])\n\t" \
"sb $4, 0(%[dst])\n\t" \
LONG_ADDI " %[src], 1\n\t" \
LONG_ADDI " %[dst], 1\n\t" \
LONG_ADDI " %[len], -1\n\t" \
"bnez %[len], 222b\n\t" \
"333:\n\t" \
RSEQ_INJECT_ASM(5)
/* final store */
LONG_S " %[newv], %[v]\n\t"
"2:\n\t"
RSEQ_INJECT_ASM(6)
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t"
"b 8f\n\t"
RSEQ_ASM_DEFINE_ABORT(3, 4,
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t",
abort, 1b, 2b, 4f)
RSEQ_ASM_DEFINE_CMPFAIL(5,
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t",
cmpfail)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_CMPFAIL(6,
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t",
error1)
RSEQ_ASM_DEFINE_CMPFAIL(7,
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t",
error2)
#endif
"8:\n\t"
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
[current_cpu_id] "m" (__rseq_abi.cpu_id),
[rseq_cs] "m" (__rseq_abi.rseq_cs),
/* final store input */
[v] "m" (*v),
[expect] "r" (expect),
[newv] "r" (newv),
/* try memcpy input */
[dst] "r" (dst),
[src] "r" (src),
[len] "r" (len),
[rseq_scratch0] "m" (rseq_scratch[0]),
[rseq_scratch1] "m" (rseq_scratch[1]),
[rseq_scratch2] "m" (rseq_scratch[2])
RSEQ_INJECT_INPUT
: "$4", "memory"
RSEQ_INJECT_CLOBBER
: abort, cmpfail
#ifdef RSEQ_COMPARE_TWICE
, error1, error2
#endif
);
rseq_workaround_gcc_asm_size_guess();
return 0;
abort:
rseq_workaround_gcc_asm_size_guess();
RSEQ_INJECT_FAILED
return -1;
cmpfail:
rseq_workaround_gcc_asm_size_guess();
return 1;
#ifdef RSEQ_COMPARE_TWICE
error1:
rseq_workaround_gcc_asm_size_guess();
rseq_bug("cpu_id comparison failed");
error2:
rseq_workaround_gcc_asm_size_guess();
rseq_bug("expected value comparison failed");
#endif
}
static inline __attribute__((always_inline))
int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
void *dst, void *src, size_t len,
intptr_t newv, int cpu)
{
uintptr_t rseq_scratch[3];
RSEQ_INJECT_C(9)
rseq_workaround_gcc_asm_size_guess();
__asm__ __volatile__ goto (
RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail])
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1])
RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2])
#endif
LONG_S " %[src], %[rseq_scratch0]\n\t"
LONG_S " %[dst], %[rseq_scratch1]\n\t"
LONG_S " %[len], %[rseq_scratch2]\n\t"
/* Start rseq by storing table entry pointer into rseq_cs. */
RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs)
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
RSEQ_INJECT_ASM(3)
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], 5f\n\t"
RSEQ_INJECT_ASM(4)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f)
LONG_L " $4, %[v]\n\t"
"bne $4, %[expect], 7f\n\t"
#endif
/* try memcpy */
"beqz %[len], 333f\n\t" \
"222:\n\t" \
"lb $4, 0(%[src])\n\t" \
"sb $4, 0(%[dst])\n\t" \
LONG_ADDI " %[src], 1\n\t" \
LONG_ADDI " %[dst], 1\n\t" \
LONG_ADDI " %[len], -1\n\t" \
"bnez %[len], 222b\n\t" \
"333:\n\t" \
RSEQ_INJECT_ASM(5)
"sync\n\t" /* full sync provides store-release */
/* final store */
LONG_S " %[newv], %[v]\n\t"
"2:\n\t"
RSEQ_INJECT_ASM(6)
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t"
"b 8f\n\t"
RSEQ_ASM_DEFINE_ABORT(3, 4,
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t",
abort, 1b, 2b, 4f)
RSEQ_ASM_DEFINE_CMPFAIL(5,
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t",
cmpfail)
#ifdef RSEQ_COMPARE_TWICE
RSEQ_ASM_DEFINE_CMPFAIL(6,
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t",
error1)
RSEQ_ASM_DEFINE_CMPFAIL(7,
/* teardown */
LONG_L " %[len], %[rseq_scratch2]\n\t"
LONG_L " %[dst], %[rseq_scratch1]\n\t"
LONG_L " %[src], %[rseq_scratch0]\n\t",
error2)
#endif
"8:\n\t"
: /* gcc asm goto does not allow outputs */
: [cpu_id] "r" (cpu),
[current_cpu_id] "m" (__rseq_abi.cpu_id),
[rseq_cs] "m" (__rseq_abi.rseq_cs),
/* final store input */
[v] "m" (*v),
[expect] "r" (expect),
[newv] "r" (newv),
/* try memcpy input */
[dst] "r" (dst),
[src] "r" (src),
[len] "r" (len),
[rseq_scratch0] "m" (rseq_scratch[0]),
[rseq_scratch1] "m" (rseq_scratch[1]),
[rseq_scratch2] "m" (rseq_scratch[2])
RSEQ_INJECT_INPUT
: "$4", "memory"
RSEQ_INJECT_CLOBBER
: abort, cmpfail
#ifdef RSEQ_COMPARE_TWICE
, error1, error2
#endif
);
rseq_workaround_gcc_asm_size_guess();
return 0;
abort:
rseq_workaround_gcc_asm_size_guess();
RSEQ_INJECT_FAILED
return -1;
cmpfail:
rseq_workaround_gcc_asm_size_guess();
return 1;
#ifdef RSEQ_COMPARE_TWICE
error1:
rseq_workaround_gcc_asm_size_guess();
rseq_bug("cpu_id comparison failed");
error2:
rseq_workaround_gcc_asm_size_guess();
rseq_bug("expected value comparison failed");
#endif
}
#endif /* !RSEQ_SKIP_FASTPATH */