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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_LINKAGE_H
#define __ASM_LINKAGE_H
#define __ALIGN .align 2
#define __ALIGN_STR __stringify(__ALIGN)
#define SYM_FUNC_START(name) \
SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN) \
.cfi_startproc;
#define SYM_FUNC_START_NOALIGN(name) \
SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE) \
.cfi_startproc;
#define SYM_FUNC_START_LOCAL(name) \
SYM_START(name, SYM_L_LOCAL, SYM_A_ALIGN) \
.cfi_startproc;
#define SYM_FUNC_START_LOCAL_NOALIGN(name) \
SYM_START(name, SYM_L_LOCAL, SYM_A_NONE) \
.cfi_startproc;
#define SYM_FUNC_START_WEAK(name) \
SYM_START(name, SYM_L_WEAK, SYM_A_ALIGN) \
.cfi_startproc;
#define SYM_FUNC_START_WEAK_NOALIGN(name) \
SYM_START(name, SYM_L_WEAK, SYM_A_NONE) \
.cfi_startproc;
#define SYM_FUNC_END(name) \
.cfi_endproc; \
SYM_END(name, SYM_T_FUNC)
#define SYM_CODE_START(name) \
SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN) \
.cfi_startproc;
#define SYM_CODE_END(name) \
.cfi_endproc; \
SYM_END(name, SYM_T_NONE)
/*
* This is for the signal handler trampoline, which is used as the return
* address of the signal handlers in userspace instead of called normally.
* The long standing libgcc bug https://gcc.gnu.org/PR124050 requires a
* nop between .cfi_startproc and the actual address of the trampoline, so
* we cannot simply use SYM_FUNC_START.
*
* This wrapper also contains all the .cfi_* directives for recovering
* the content of the GPRs and the "return address" (where the rt_sigreturn
* syscall will jump to), assuming there is a struct rt_sigframe (where
* a struct sigcontext containing those information we need to recover) at
* $sp. The "DWARF for the LoongArch(TM) Architecture" manual states
* column 0 is for $zero, but it does not make too much sense to
* save/restore the hardware zero register. Repurpose this column here
* for the return address (here it's not the content of $ra we cannot use
* the default column 3).
*/
#define SYM_SIGFUNC_START(name) \
.cfi_startproc; \
.cfi_signal_frame; \
.cfi_def_cfa 3, RT_SIGFRAME_SC; \
.cfi_return_column 0; \
.cfi_offset 0, SC_PC; \
\
.irp num, 1, 2, 3, 4, 5, 6, 7, 8, \
9, 10, 11, 12, 13, 14, 15, 16, \
17, 18, 19, 20, 21, 22, 23, 24, \
25, 26, 27, 28, 29, 30, 31; \
.cfi_offset \num, SC_REGS + \num * SZREG; \
.endr; \
\
nop; \
SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN)
#define SYM_SIGFUNC_END(name) SYM_FUNC_END(name)
#endif
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