POPL BP
RET
+TEXT runtime·thrkill_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $12, SP
+ MOVL 20(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL AX, 0(SP) // arg 1 - tid
+ MOVL BX, 4(SP) // arg 2 - signal
+ MOVL $0, 8(SP) // arg 3 - tcb
+ CALL libc_thrkill(SB)
+ MOVL BP, SP
+ POPL BP
+ RET
+
TEXT runtime·thrsleep_trampoline(SB),NOSPLIT,$0
PUSHL BP
MOVL SP, BP
POPL BP
RET
+TEXT runtime·exit_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $4, SP
+ MOVL 12(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL AX, 0(SP) // arg 1 - status
+ CALL libc_exit(SB)
+ MOVL $0xf1, 0xf1 // crash on failure
+ MOVL BP, SP
+ POPL BP
+ RET
+
+TEXT runtime·getthrid_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ CALL libc_getthrid(SB)
+ NOP SP // tell vet SP changed - stop checking offsets
+ MOVL 8(SP), DX // pointer to return value
+ MOVL AX, 0(DX)
+ POPL BP
+ RET
+
+TEXT runtime·raiseproc_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $8, SP
+ MOVL 16(SP), DX
+ MOVL 0(DX), BX
+ CALL libc_getpid(SB)
+ MOVL AX, 0(SP) // arg 1 - pid
+ MOVL BX, 4(SP) // arg 2 - signal
+ CALL libc_kill(SB)
+ MOVL BP, SP
+ POPL BP
+ RET
+
TEXT runtime·sched_yield_trampoline(SB),NOSPLIT,$0
PUSHL BP
MOVL SP, BP
POPL BP
RET
-// Exit the entire program (like C exit)
-TEXT runtime·exit(SB),NOSPLIT,$-4
- MOVL $1, AX
- INT $0x80
- MOVL $0xf1, 0xf1 // crash
+TEXT runtime·mmap_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $32, SP
+ MOVL 40(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - addr
+ MOVL BX, 4(SP) // arg 2 - len
+ MOVL CX, 8(SP) // arg 3 - prot
+ MOVL 12(DX), AX
+ MOVL 16(DX), BX
+ MOVL 20(DX), CX
+ MOVL AX, 12(SP) // arg 4 - flags
+ MOVL BX, 16(SP) // arg 5 - fid
+ MOVL $0, 20(SP) // pad
+ MOVL CX, 24(SP) // arg 6 - offset (low 32 bits)
+ MOVL $0, 28(SP) // offset (high 32 bits)
+ CALL libc_mmap(SB)
+ MOVL $0, BX
+ CMPL AX, $-1
+ JNE ok
+ CALL libc_errno(SB)
+ MOVL (AX), BX
+ MOVL $0, AX
+ok:
+ MOVL 40(SP), DX
+ MOVL AX, 24(DX)
+ MOVL BX, 28(DX)
+ MOVL BP, SP
+ POPL BP
RET
-// func exitThread(wait *uint32)
-TEXT runtime·exitThread(SB),NOSPLIT,$0-4
- MOVL $302, AX // sys___threxit
- INT $0x80
- MOVL $0xf1, 0xf1 // crash
- JMP 0(PC)
+TEXT runtime·munmap_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $8, SP
+ MOVL 16(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL AX, 0(SP) // arg 1 - addr
+ MOVL BX, 4(SP) // arg 2 - len
+ CALL libc_munmap(SB)
+ CMPL AX, $-1
+ JNE 2(PC)
+ MOVL $0xf1, 0xf1 // crash on failure
+ MOVL BP, SP
+ POPL BP
+ RET
+
+TEXT runtime·madvise_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $12, SP
+ MOVL 20(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - addr
+ MOVL BX, 4(SP) // arg 2 - len
+ MOVL CX, 8(SP) // arg 3 - advice
+ CALL libc_madvise(SB)
+ // ignore failure - maybe pages are locked
+ MOVL BP, SP
+ POPL BP
+ RET
-TEXT runtime·open(SB),NOSPLIT,$-4
- MOVL $5, AX
- INT $0x80
- JAE 2(PC)
- MOVL $-1, AX
- MOVL AX, ret+12(FP)
+TEXT runtime·open_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $16, SP
+ MOVL 24(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - path
+ MOVL BX, 4(SP) // arg 2 - flags
+ MOVL CX, 8(SP) // arg 3 - mode
+ MOVL $0, 12(SP) // vararg
+ CALL libc_open(SB)
+ MOVL BP, SP
+ POPL BP
RET
-TEXT runtime·closefd(SB),NOSPLIT,$-4
- MOVL $6, AX
- INT $0x80
- JAE 2(PC)
- MOVL $-1, AX
- MOVL AX, ret+4(FP)
+TEXT runtime·close_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $4, SP
+ MOVL 12(SP), DX
+ MOVL 0(DX), AX
+ MOVL AX, 0(SP) // arg 1 - fd
+ CALL libc_close(SB)
+ MOVL BP, SP
+ POPL BP
RET
-TEXT runtime·read(SB),NOSPLIT,$-4
- MOVL $3, AX
- INT $0x80
- JAE 2(PC)
+TEXT runtime·read_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $12, SP
+ MOVL 20(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - fd
+ MOVL BX, 4(SP) // arg 2 - buf
+ MOVL CX, 8(SP) // arg 3 - count
+ CALL libc_read(SB)
+ CMPL AX, $-1
+ JNE noerr
+ CALL libc_errno(SB)
+ MOVL (AX), AX
NEGL AX // caller expects negative errno
- MOVL AX, ret+12(FP)
+noerr:
+ MOVL BP, SP
+ POPL BP
RET
-// func pipe() (r, w int32, errno int32)
-TEXT runtime·pipe(SB),NOSPLIT,$8-12
- MOVL $263, AX
- LEAL r+0(FP), BX
- MOVL BX, 4(SP)
- INT $0x80
- MOVL AX, errno+8(FP)
+TEXT runtime·write_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $12, SP
+ MOVL 20(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - fd
+ MOVL BX, 4(SP) // arg 2 - buf
+ MOVL CX, 8(SP) // arg 3 - count
+ CALL libc_write(SB)
+ CMPL AX, $-1
+ JNE noerr
+ CALL libc_errno(SB)
+ MOVL (AX), AX
+ NEGL AX // caller expects negative errno
+noerr:
+ MOVL BP, SP
+ POPL BP
RET
-// func pipe2(flags int32) (r, w int32, errno int32)
-TEXT runtime·pipe2(SB),NOSPLIT,$12-16
- MOVL $101, AX
- LEAL r+4(FP), BX
- MOVL BX, 4(SP)
- MOVL flags+0(FP), BX
- MOVL BX, 8(SP)
- INT $0x80
- MOVL AX, errno+12(FP)
+TEXT runtime·pipe2_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $8, SP
+ MOVL 16(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL AX, 0(SP) // arg 1 - fds
+ MOVL BX, 4(SP) // arg 2 - flags
+ CALL libc_pipe2(SB)
+ CMPL AX, $-1
+ JNE noerr
+ CALL libc_errno(SB)
+ MOVL (AX), AX
+ NEGL AX // caller expects negative errno
+noerr:
+ MOVL BP, SP
+ POPL BP
+ RET
+
+TEXT runtime·setitimer_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $12, SP
+ MOVL 20(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - which
+ MOVL BX, 4(SP) // arg 2 - new
+ MOVL CX, 8(SP) // arg 3 - old
+ CALL libc_setitimer(SB)
+ MOVL BP, SP
+ POPL BP
+ RET
+
+TEXT runtime·usleep_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $4, SP
+ MOVL 12(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL AX, 0(SP)
+ CALL libc_usleep(SB)
+ MOVL BP, SP
+ POPL BP
+ RET
+
+TEXT runtime·sysctl_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $24, SP
+ MOVL 32(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - name
+ MOVL BX, 4(SP) // arg 2 - namelen
+ MOVL CX, 8(SP) // arg 3 - old
+ MOVL 12(DX), AX
+ MOVL 16(DX), BX
+ MOVL 20(DX), CX
+ MOVL AX, 12(SP) // arg 4 - oldlenp
+ MOVL BX, 16(SP) // arg 5 - newp
+ MOVL CX, 20(SP) // arg 6 - newlen
+ CALL libc_sysctl(SB)
+ MOVL BP, SP
+ POPL BP
+ RET
+
+TEXT runtime·kqueue_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ CALL libc_kqueue(SB)
+ MOVL BP, SP
+ POPL BP
RET
-TEXT runtime·write1(SB),NOSPLIT,$-4
- MOVL $4, AX // sys_write
- INT $0x80
- JAE 2(PC)
+TEXT runtime·kevent_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $24, SP
+ MOVL 32(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - kq
+ MOVL BX, 4(SP) // arg 2 - keventt
+ MOVL CX, 8(SP) // arg 3 - nch
+ MOVL 12(DX), AX
+ MOVL 16(DX), BX
+ MOVL 20(DX), CX
+ MOVL AX, 12(SP) // arg 4 - ev
+ MOVL BX, 16(SP) // arg 5 - nev
+ MOVL CX, 20(SP) // arg 6 - ts
+ CALL libc_kevent(SB)
+ CMPL AX, $-1
+ JNE noerr
+ CALL libc_errno(SB)
+ MOVL (AX), AX
NEGL AX // caller expects negative errno
- MOVL AX, ret+12(FP)
- RET
-
-TEXT runtime·usleep(SB),NOSPLIT,$24
- MOVL $0, DX
- MOVL usec+0(FP), AX
- MOVL $1000000, CX
- DIVL CX
- MOVL AX, 12(SP) // tv_sec - l32
- MOVL $0, 16(SP) // tv_sec - h32
- MOVL $1000, AX
- MULL DX
- MOVL AX, 20(SP) // tv_nsec
-
- MOVL $0, 0(SP)
- LEAL 12(SP), AX
- MOVL AX, 4(SP) // arg 1 - rqtp
- MOVL $0, 8(SP) // arg 2 - rmtp
- MOVL $91, AX // sys_nanosleep
- INT $0x80
- RET
-
-TEXT runtime·getthrid(SB),NOSPLIT,$0-4
- MOVL $299, AX // sys_getthrid
- INT $0x80
- MOVL AX, ret+0(FP)
- RET
-
-TEXT runtime·thrkill(SB),NOSPLIT,$16-8
- MOVL $0, 0(SP)
- MOVL tid+0(FP), AX
- MOVL AX, 4(SP) // arg 1 - tid
- MOVL sig+4(FP), AX
- MOVL AX, 8(SP) // arg 2 - signum
- MOVL $0, 12(SP) // arg 3 - tcb
- MOVL $119, AX // sys_thrkill
- INT $0x80
- RET
-
-TEXT runtime·raiseproc(SB),NOSPLIT,$12
- MOVL $20, AX // sys_getpid
- INT $0x80
- MOVL $0, 0(SP)
- MOVL AX, 4(SP) // arg 1 - pid
- MOVL sig+0(FP), AX
- MOVL AX, 8(SP) // arg 2 - signum
- MOVL $122, AX // sys_kill
- INT $0x80
- RET
-
-TEXT runtime·mmap(SB),NOSPLIT,$36
- LEAL addr+0(FP), SI
- LEAL 4(SP), DI
- CLD
- MOVSL // arg 1 - addr
- MOVSL // arg 2 - len
- MOVSL // arg 3 - prot
- MOVSL // arg 4 - flags
- MOVSL // arg 5 - fd
- MOVL $0, AX
- STOSL // arg 6 - pad
- MOVSL // arg 7 - offset
- MOVL $0, AX // top 32 bits of file offset
- STOSL
- MOVL $197, AX // sys_mmap
- INT $0x80
- JAE ok
- MOVL $0, p+24(FP)
- MOVL AX, err+28(FP)
+noerr:
+ MOVL BP, SP
+ POPL BP
RET
-ok:
- MOVL AX, p+24(FP)
- MOVL $0, err+28(FP)
+
+TEXT runtime·clock_gettime_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $8, SP
+ MOVL 16(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL AX, 0(SP) // arg 1 - tp
+ MOVL BX, 4(SP) // arg 2 - clock_id
+ CALL libc_clock_gettime(SB)
+ CMPL AX, $-1
+ JNE 2(PC)
+ MOVL $0xf1, 0xf1 // crash on failure
+ MOVL BP, SP
+ POPL BP
RET
-TEXT runtime·munmap(SB),NOSPLIT,$-4
- MOVL $73, AX // sys_munmap
- INT $0x80
- JAE 2(PC)
- MOVL $0xf1, 0xf1 // crash
- RET
-
-TEXT runtime·madvise(SB),NOSPLIT,$-4
- MOVL $75, AX // sys_madvise
- INT $0x80
- JAE 2(PC)
- MOVL $-1, AX
- MOVL AX, ret+12(FP)
- RET
-
-TEXT runtime·setitimer(SB),NOSPLIT,$-4
- MOVL $69, AX
- INT $0x80
- RET
-
-// func walltime() (sec int64, nsec int32)
-TEXT runtime·walltime(SB), NOSPLIT, $32
- LEAL 12(SP), BX
- MOVL $0, 4(SP) // arg 1 - clock_id
- MOVL BX, 8(SP) // arg 2 - tp
- MOVL $87, AX // sys_clock_gettime
- INT $0x80
-
- MOVL 12(SP), AX // sec - l32
- MOVL AX, sec_lo+0(FP)
- MOVL 16(SP), AX // sec - h32
- MOVL AX, sec_hi+4(FP)
-
- MOVL 20(SP), BX // nsec
- MOVL BX, nsec+8(FP)
- RET
-
-// int64 nanotime1(void) so really
-// void nanotime1(int64 *nsec)
-TEXT runtime·nanotime1(SB),NOSPLIT,$32
- LEAL 12(SP), BX
- MOVL CLOCK_MONOTONIC, 4(SP) // arg 1 - clock_id
- MOVL BX, 8(SP) // arg 2 - tp
- MOVL $87, AX // sys_clock_gettime
- INT $0x80
-
- MOVL 16(SP), CX // sec - h32
- IMULL $1000000000, CX
-
- MOVL 12(SP), AX // sec - l32
- MOVL $1000000000, BX
- MULL BX // result in dx:ax
-
- MOVL 20(SP), BX // nsec
- ADDL BX, AX
- ADCL CX, DX // add high bits with carry
-
- MOVL AX, ret_lo+0(FP)
- MOVL DX, ret_hi+4(FP)
- RET
-
-TEXT runtime·sigaction(SB),NOSPLIT,$-4
- MOVL $46, AX // sys_sigaction
- INT $0x80
- JAE 2(PC)
- MOVL $0xf1, 0xf1 // crash
- RET
-
-TEXT runtime·obsdsigprocmask(SB),NOSPLIT,$-4
- MOVL $48, AX // sys_sigprocmask
- INT $0x80
- JAE 2(PC)
- MOVL $0xf1, 0xf1 // crash
- MOVL AX, ret+8(FP)
- RET
-
-TEXT runtime·sigaltstack(SB),NOSPLIT,$-8
- MOVL $288, AX // sys_sigaltstack
- MOVL new+0(FP), BX
- MOVL old+4(FP), CX
- INT $0x80
- CMPL AX, $0xfffff001
- JLS 2(PC)
- INT $3
- RET
-
-TEXT set_tcb<>(SB),NOSPLIT,$8
- // adjust for ELF: wants to use -4(GS) for g
- MOVL tlsbase+0(FP), CX
- ADDL $4, CX
- MOVL $0, 0(SP) // syscall gap
- MOVL CX, 4(SP) // arg 1 - tcb
- MOVL $329, AX // sys___set_tcb
- INT $0x80
- JCC 2(PC)
- MOVL $0xf1, 0xf1 // crash
- RET
-
-TEXT runtime·sysctl(SB),NOSPLIT,$28
- LEAL mib+0(FP), SI
- LEAL 4(SP), DI
- CLD
- MOVSL // arg 1 - name
- MOVSL // arg 2 - namelen
- MOVSL // arg 3 - oldp
- MOVSL // arg 4 - oldlenp
- MOVSL // arg 5 - newp
- MOVSL // arg 6 - newlen
- MOVL $202, AX // sys___sysctl
- INT $0x80
- JCC 4(PC)
- NEGL AX
- MOVL AX, ret+24(FP)
+TEXT runtime·fcntl_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $16, SP
+ MOVL 24(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - fd
+ MOVL BX, 4(SP) // arg 2 - cmd
+ MOVL CX, 8(SP) // arg 3 - arg
+ MOVL $0, 12(SP) // vararg
+ CALL libc_fcntl(SB)
+ MOVL BP, SP
+ POPL BP
RET
- MOVL $0, AX
- MOVL AX, ret+24(FP)
- RET
-
-// int32 runtime·kqueue(void);
-TEXT runtime·kqueue(SB),NOSPLIT,$0
- MOVL $269, AX
- INT $0x80
- JAE 2(PC)
- NEGL AX
- MOVL AX, ret+0(FP)
- RET
-
-// int32 runtime·kevent(int kq, Kevent *changelist, int nchanges, Kevent *eventlist, int nevents, Timespec *timeout);
-TEXT runtime·kevent(SB),NOSPLIT,$0
- MOVL $72, AX // sys_kevent
- INT $0x80
- JAE 2(PC)
- NEGL AX
- MOVL AX, ret+24(FP)
- RET
-
-// int32 runtime·closeonexec(int32 fd);
-TEXT runtime·closeonexec(SB),NOSPLIT,$32
- MOVL $92, AX // sys_fcntl
- // 0(SP) is where the caller PC would be; kernel skips it
- MOVL fd+0(FP), BX
- MOVL BX, 4(SP) // fd
- MOVL $2, 8(SP) // F_SETFD
- MOVL $1, 12(SP) // FD_CLOEXEC
- INT $0x80
- JAE 2(PC)
- NEGL AX
- RET
-
-// func runtime·setNonblock(fd int32)
-TEXT runtime·setNonblock(SB),NOSPLIT,$16-4
- MOVL $92, AX // fcntl
- MOVL fd+0(FP), BX // fd
- MOVL BX, 4(SP)
- MOVL $3, 8(SP) // F_GETFL
- MOVL $0, 12(SP)
- INT $0x80
- MOVL fd+0(FP), BX // fd
- MOVL BX, 4(SP)
- MOVL $4, 8(SP) // F_SETFL
- ORL $4, AX // O_NONBLOCK
- MOVL AX, 12(SP)
- MOVL $92, AX // fcntl
- INT $0x80
+
+TEXT runtime·sigaction_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $12, SP
+ MOVL 20(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - sig
+ MOVL BX, 4(SP) // arg 2 - new
+ MOVL CX, 8(SP) // arg 3 - old
+ CALL libc_sigaction(SB)
+ CMPL AX, $-1
+ JNE 2(PC)
+ MOVL $0xf1, 0xf1 // crash on failure
+ MOVL BP, SP
+ POPL BP
RET
-GLOBL runtime·tlsoffset(SB),NOPTR,$4
+TEXT runtime·sigprocmask_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $12, SP
+ MOVL 20(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL 8(DX), CX
+ MOVL AX, 0(SP) // arg 1 - how
+ MOVL BX, 4(SP) // arg 2 - new
+ MOVL CX, 8(SP) // arg 3 - old
+ CALL libc_pthread_sigmask(SB)
+ CMPL AX, $-1
+ JNE 2(PC)
+ MOVL $0xf1, 0xf1 // crash on failure
+ MOVL BP, SP
+ POPL BP
+ RET
+
+TEXT runtime·sigaltstack_trampoline(SB),NOSPLIT,$0
+ PUSHL BP
+ MOVL SP, BP
+ SUBL $8, SP
+ MOVL 16(SP), DX // pointer to args
+ MOVL 0(DX), AX
+ MOVL 4(DX), BX
+ MOVL AX, 0(SP) // arg 1 - new
+ MOVL BX, 4(SP) // arg 2 - old
+ CALL libc_sigaltstack(SB)
+ CMPL AX, $-1
+ JNE 2(PC)
+ MOVL $0xf1, 0xf1 // crash on failure
+ MOVL BP, SP
+ POPL BP
+ RET