summaryrefslogtreecommitdiffstats
path: root/src/runtime/sys_linux_arm64.s
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:23:18 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:23:18 +0000
commit43a123c1ae6613b3efeed291fa552ecd909d3acf (patch)
treefd92518b7024bc74031f78a1cf9e454b65e73665 /src/runtime/sys_linux_arm64.s
parentInitial commit. (diff)
downloadgolang-1.20-upstream.tar.xz
golang-1.20-upstream.zip
Adding upstream version 1.20.14.upstream/1.20.14upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/runtime/sys_linux_arm64.s')
-rw-r--r--src/runtime/sys_linux_arm64.s801
1 files changed, 801 insertions, 0 deletions
diff --git a/src/runtime/sys_linux_arm64.s b/src/runtime/sys_linux_arm64.s
new file mode 100644
index 0000000..38ff6ac
--- /dev/null
+++ b/src/runtime/sys_linux_arm64.s
@@ -0,0 +1,801 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//
+// System calls and other sys.stuff for arm64, Linux
+//
+
+#include "go_asm.h"
+#include "go_tls.h"
+#include "textflag.h"
+#include "cgo/abi_arm64.h"
+
+#define AT_FDCWD -100
+
+#define CLOCK_REALTIME 0
+#define CLOCK_MONOTONIC 1
+
+#define SYS_exit 93
+#define SYS_read 63
+#define SYS_write 64
+#define SYS_openat 56
+#define SYS_close 57
+#define SYS_pipe2 59
+#define SYS_nanosleep 101
+#define SYS_mmap 222
+#define SYS_munmap 215
+#define SYS_setitimer 103
+#define SYS_clone 220
+#define SYS_sched_yield 124
+#define SYS_rt_sigreturn 139
+#define SYS_rt_sigaction 134
+#define SYS_rt_sigprocmask 135
+#define SYS_sigaltstack 132
+#define SYS_madvise 233
+#define SYS_mincore 232
+#define SYS_getpid 172
+#define SYS_gettid 178
+#define SYS_kill 129
+#define SYS_tgkill 131
+#define SYS_futex 98
+#define SYS_sched_getaffinity 123
+#define SYS_exit_group 94
+#define SYS_clock_gettime 113
+#define SYS_faccessat 48
+#define SYS_socket 198
+#define SYS_connect 203
+#define SYS_brk 214
+#define SYS_timer_create 107
+#define SYS_timer_settime 110
+#define SYS_timer_delete 111
+
+TEXT runtime·exit(SB),NOSPLIT|NOFRAME,$0-4
+ MOVW code+0(FP), R0
+ MOVD $SYS_exit_group, R8
+ SVC
+ RET
+
+// func exitThread(wait *atomic.Uint32)
+TEXT runtime·exitThread(SB),NOSPLIT|NOFRAME,$0-8
+ MOVD wait+0(FP), R0
+ // We're done using the stack.
+ MOVW $0, R1
+ STLRW R1, (R0)
+ MOVW $0, R0 // exit code
+ MOVD $SYS_exit, R8
+ SVC
+ JMP 0(PC)
+
+TEXT runtime·open(SB),NOSPLIT|NOFRAME,$0-20
+ MOVD $AT_FDCWD, R0
+ MOVD name+0(FP), R1
+ MOVW mode+8(FP), R2
+ MOVW perm+12(FP), R3
+ MOVD $SYS_openat, R8
+ SVC
+ CMN $4095, R0
+ BCC done
+ MOVW $-1, R0
+done:
+ MOVW R0, ret+16(FP)
+ RET
+
+TEXT runtime·closefd(SB),NOSPLIT|NOFRAME,$0-12
+ MOVW fd+0(FP), R0
+ MOVD $SYS_close, R8
+ SVC
+ CMN $4095, R0
+ BCC done
+ MOVW $-1, R0
+done:
+ MOVW R0, ret+8(FP)
+ RET
+
+TEXT runtime·write1(SB),NOSPLIT|NOFRAME,$0-28
+ MOVD fd+0(FP), R0
+ MOVD p+8(FP), R1
+ MOVW n+16(FP), R2
+ MOVD $SYS_write, R8
+ SVC
+ MOVW R0, ret+24(FP)
+ RET
+
+TEXT runtime·read(SB),NOSPLIT|NOFRAME,$0-28
+ MOVW fd+0(FP), R0
+ MOVD p+8(FP), R1
+ MOVW n+16(FP), R2
+ MOVD $SYS_read, R8
+ SVC
+ MOVW R0, ret+24(FP)
+ RET
+
+// func pipe2(flags int32) (r, w int32, errno int32)
+TEXT runtime·pipe2(SB),NOSPLIT|NOFRAME,$0-20
+ MOVD $r+8(FP), R0
+ MOVW flags+0(FP), R1
+ MOVW $SYS_pipe2, R8
+ SVC
+ MOVW R0, errno+16(FP)
+ RET
+
+TEXT runtime·usleep(SB),NOSPLIT,$24-4
+ MOVWU usec+0(FP), R3
+ MOVD R3, R5
+ MOVW $1000000, R4
+ UDIV R4, R3
+ MOVD R3, 8(RSP)
+ MUL R3, R4
+ SUB R4, R5
+ MOVW $1000, R4
+ MUL R4, R5
+ MOVD R5, 16(RSP)
+
+ // nanosleep(&ts, 0)
+ ADD $8, RSP, R0
+ MOVD $0, R1
+ MOVD $SYS_nanosleep, R8
+ SVC
+ RET
+
+TEXT runtime·gettid(SB),NOSPLIT,$0-4
+ MOVD $SYS_gettid, R8
+ SVC
+ MOVW R0, ret+0(FP)
+ RET
+
+TEXT runtime·raise(SB),NOSPLIT|NOFRAME,$0
+ MOVD $SYS_getpid, R8
+ SVC
+ MOVW R0, R19
+ MOVD $SYS_gettid, R8
+ SVC
+ MOVW R0, R1 // arg 2 tid
+ MOVW R19, R0 // arg 1 pid
+ MOVW sig+0(FP), R2 // arg 3
+ MOVD $SYS_tgkill, R8
+ SVC
+ RET
+
+TEXT runtime·raiseproc(SB),NOSPLIT|NOFRAME,$0
+ MOVD $SYS_getpid, R8
+ SVC
+ MOVW R0, R0 // arg 1 pid
+ MOVW sig+0(FP), R1 // arg 2
+ MOVD $SYS_kill, R8
+ SVC
+ RET
+
+TEXT ·getpid(SB),NOSPLIT|NOFRAME,$0-8
+ MOVD $SYS_getpid, R8
+ SVC
+ MOVD R0, ret+0(FP)
+ RET
+
+TEXT ·tgkill(SB),NOSPLIT,$0-24
+ MOVD tgid+0(FP), R0
+ MOVD tid+8(FP), R1
+ MOVD sig+16(FP), R2
+ MOVD $SYS_tgkill, R8
+ SVC
+ RET
+
+TEXT runtime·setitimer(SB),NOSPLIT|NOFRAME,$0-24
+ MOVW mode+0(FP), R0
+ MOVD new+8(FP), R1
+ MOVD old+16(FP), R2
+ MOVD $SYS_setitimer, R8
+ SVC
+ RET
+
+TEXT runtime·timer_create(SB),NOSPLIT,$0-28
+ MOVW clockid+0(FP), R0
+ MOVD sevp+8(FP), R1
+ MOVD timerid+16(FP), R2
+ MOVD $SYS_timer_create, R8
+ SVC
+ MOVW R0, ret+24(FP)
+ RET
+
+TEXT runtime·timer_settime(SB),NOSPLIT,$0-28
+ MOVW timerid+0(FP), R0
+ MOVW flags+4(FP), R1
+ MOVD new+8(FP), R2
+ MOVD old+16(FP), R3
+ MOVD $SYS_timer_settime, R8
+ SVC
+ MOVW R0, ret+24(FP)
+ RET
+
+TEXT runtime·timer_delete(SB),NOSPLIT,$0-12
+ MOVW timerid+0(FP), R0
+ MOVD $SYS_timer_delete, R8
+ SVC
+ MOVW R0, ret+8(FP)
+ RET
+
+TEXT runtime·mincore(SB),NOSPLIT|NOFRAME,$0-28
+ MOVD addr+0(FP), R0
+ MOVD n+8(FP), R1
+ MOVD dst+16(FP), R2
+ MOVD $SYS_mincore, R8
+ SVC
+ MOVW R0, ret+24(FP)
+ RET
+
+// func walltime() (sec int64, nsec int32)
+TEXT runtime·walltime(SB),NOSPLIT,$24-12
+ MOVD RSP, R20 // R20 is unchanged by C code
+ MOVD RSP, R1
+
+ MOVD g_m(g), R21 // R21 = m
+
+ // Set vdsoPC and vdsoSP for SIGPROF traceback.
+ // Save the old values on stack and restore them on exit,
+ // so this function is reentrant.
+ MOVD m_vdsoPC(R21), R2
+ MOVD m_vdsoSP(R21), R3
+ MOVD R2, 8(RSP)
+ MOVD R3, 16(RSP)
+
+ MOVD $ret-8(FP), R2 // caller's SP
+ MOVD LR, m_vdsoPC(R21)
+ MOVD R2, m_vdsoSP(R21)
+
+ MOVD m_curg(R21), R0
+ CMP g, R0
+ BNE noswitch
+
+ MOVD m_g0(R21), R3
+ MOVD (g_sched+gobuf_sp)(R3), R1 // Set RSP to g0 stack
+
+noswitch:
+ SUB $16, R1
+ BIC $15, R1 // Align for C code
+ MOVD R1, RSP
+
+ MOVW $CLOCK_REALTIME, R0
+ MOVD runtime·vdsoClockgettimeSym(SB), R2
+ CBZ R2, fallback
+
+ // Store g on gsignal's stack, so if we receive a signal
+ // during VDSO code we can find the g.
+ // If we don't have a signal stack, we won't receive signal,
+ // so don't bother saving g.
+ // When using cgo, we already saved g on TLS, also don't save
+ // g here.
+ // Also don't save g if we are already on the signal stack.
+ // We won't get a nested signal.
+ MOVBU runtime·iscgo(SB), R22
+ CBNZ R22, nosaveg
+ MOVD m_gsignal(R21), R22 // g.m.gsignal
+ CBZ R22, nosaveg
+ CMP g, R22
+ BEQ nosaveg
+ MOVD (g_stack+stack_lo)(R22), R22 // g.m.gsignal.stack.lo
+ MOVD g, (R22)
+
+ BL (R2)
+
+ MOVD ZR, (R22) // clear g slot, R22 is unchanged by C code
+
+ B finish
+
+nosaveg:
+ BL (R2)
+ B finish
+
+fallback:
+ MOVD $SYS_clock_gettime, R8
+ SVC
+
+finish:
+ MOVD 0(RSP), R3 // sec
+ MOVD 8(RSP), R5 // nsec
+
+ MOVD R20, RSP // restore SP
+ // Restore vdsoPC, vdsoSP
+ // We don't worry about being signaled between the two stores.
+ // If we are not in a signal handler, we'll restore vdsoSP to 0,
+ // and no one will care about vdsoPC. If we are in a signal handler,
+ // we cannot receive another signal.
+ MOVD 16(RSP), R1
+ MOVD R1, m_vdsoSP(R21)
+ MOVD 8(RSP), R1
+ MOVD R1, m_vdsoPC(R21)
+
+ MOVD R3, sec+0(FP)
+ MOVW R5, nsec+8(FP)
+ RET
+
+TEXT runtime·nanotime1(SB),NOSPLIT,$24-8
+ MOVD RSP, R20 // R20 is unchanged by C code
+ MOVD RSP, R1
+
+ MOVD g_m(g), R21 // R21 = m
+
+ // Set vdsoPC and vdsoSP for SIGPROF traceback.
+ // Save the old values on stack and restore them on exit,
+ // so this function is reentrant.
+ MOVD m_vdsoPC(R21), R2
+ MOVD m_vdsoSP(R21), R3
+ MOVD R2, 8(RSP)
+ MOVD R3, 16(RSP)
+
+ MOVD $ret-8(FP), R2 // caller's SP
+ MOVD LR, m_vdsoPC(R21)
+ MOVD R2, m_vdsoSP(R21)
+
+ MOVD m_curg(R21), R0
+ CMP g, R0
+ BNE noswitch
+
+ MOVD m_g0(R21), R3
+ MOVD (g_sched+gobuf_sp)(R3), R1 // Set RSP to g0 stack
+
+noswitch:
+ SUB $32, R1
+ BIC $15, R1
+ MOVD R1, RSP
+
+ MOVW $CLOCK_MONOTONIC, R0
+ MOVD runtime·vdsoClockgettimeSym(SB), R2
+ CBZ R2, fallback
+
+ // Store g on gsignal's stack, so if we receive a signal
+ // during VDSO code we can find the g.
+ // If we don't have a signal stack, we won't receive signal,
+ // so don't bother saving g.
+ // When using cgo, we already saved g on TLS, also don't save
+ // g here.
+ // Also don't save g if we are already on the signal stack.
+ // We won't get a nested signal.
+ MOVBU runtime·iscgo(SB), R22
+ CBNZ R22, nosaveg
+ MOVD m_gsignal(R21), R22 // g.m.gsignal
+ CBZ R22, nosaveg
+ CMP g, R22
+ BEQ nosaveg
+ MOVD (g_stack+stack_lo)(R22), R22 // g.m.gsignal.stack.lo
+ MOVD g, (R22)
+
+ BL (R2)
+
+ MOVD ZR, (R22) // clear g slot, R22 is unchanged by C code
+
+ B finish
+
+nosaveg:
+ BL (R2)
+ B finish
+
+fallback:
+ MOVD $SYS_clock_gettime, R8
+ SVC
+
+finish:
+ MOVD 0(RSP), R3 // sec
+ MOVD 8(RSP), R5 // nsec
+
+ MOVD R20, RSP // restore SP
+ // Restore vdsoPC, vdsoSP
+ // We don't worry about being signaled between the two stores.
+ // If we are not in a signal handler, we'll restore vdsoSP to 0,
+ // and no one will care about vdsoPC. If we are in a signal handler,
+ // we cannot receive another signal.
+ MOVD 16(RSP), R1
+ MOVD R1, m_vdsoSP(R21)
+ MOVD 8(RSP), R1
+ MOVD R1, m_vdsoPC(R21)
+
+ // sec is in R3, nsec in R5
+ // return nsec in R3
+ MOVD $1000000000, R4
+ MUL R4, R3
+ ADD R5, R3
+ MOVD R3, ret+0(FP)
+ RET
+
+TEXT runtime·rtsigprocmask(SB),NOSPLIT|NOFRAME,$0-28
+ MOVW how+0(FP), R0
+ MOVD new+8(FP), R1
+ MOVD old+16(FP), R2
+ MOVW size+24(FP), R3
+ MOVD $SYS_rt_sigprocmask, R8
+ SVC
+ CMN $4095, R0
+ BCC done
+ MOVD $0, R0
+ MOVD R0, (R0) // crash
+done:
+ RET
+
+TEXT runtime·rt_sigaction(SB),NOSPLIT|NOFRAME,$0-36
+ MOVD sig+0(FP), R0
+ MOVD new+8(FP), R1
+ MOVD old+16(FP), R2
+ MOVD size+24(FP), R3
+ MOVD $SYS_rt_sigaction, R8
+ SVC
+ MOVW R0, ret+32(FP)
+ RET
+
+// Call the function stored in _cgo_sigaction using the GCC calling convention.
+TEXT runtime·callCgoSigaction(SB),NOSPLIT,$0
+ MOVD sig+0(FP), R0
+ MOVD new+8(FP), R1
+ MOVD old+16(FP), R2
+ MOVD _cgo_sigaction(SB), R3
+ SUB $16, RSP // reserve 16 bytes for sp-8 where fp may be saved.
+ BL R3
+ ADD $16, RSP
+ MOVW R0, ret+24(FP)
+ RET
+
+TEXT runtime·sigfwd(SB),NOSPLIT,$0-32
+ MOVW sig+8(FP), R0
+ MOVD info+16(FP), R1
+ MOVD ctx+24(FP), R2
+ MOVD fn+0(FP), R11
+ BL (R11)
+ RET
+
+// Called from c-abi, R0: sig, R1: info, R2: cxt
+TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME,$176
+ // Save callee-save registers in the case of signal forwarding.
+ // Please refer to https://golang.org/issue/31827 .
+ SAVE_R19_TO_R28(8*4)
+ SAVE_F8_TO_F15(8*14)
+
+ // this might be called in external code context,
+ // where g is not set.
+ // first save R0, because runtime·load_g will clobber it
+ MOVW R0, 8(RSP)
+ MOVBU runtime·iscgo(SB), R0
+ CBZ R0, 2(PC)
+ BL runtime·load_g(SB)
+
+#ifdef GOEXPERIMENT_regabiargs
+ // Restore signum to R0.
+ MOVW 8(RSP), R0
+ // R1 and R2 already contain info and ctx, respectively.
+#else
+ MOVD R1, 16(RSP)
+ MOVD R2, 24(RSP)
+#endif
+ MOVD $runtime·sigtrampgo<ABIInternal>(SB), R3
+ BL (R3)
+
+ // Restore callee-save registers.
+ RESTORE_R19_TO_R28(8*4)
+ RESTORE_F8_TO_F15(8*14)
+
+ RET
+
+// Called from c-abi, R0: sig, R1: info, R2: cxt
+TEXT runtime·sigprofNonGoWrapper<>(SB),NOSPLIT,$176
+ // Save callee-save registers because it's a callback from c code.
+ SAVE_R19_TO_R28(8*4)
+ SAVE_F8_TO_F15(8*14)
+
+#ifdef GOEXPERIMENT_regabiargs
+ // R0, R1 and R2 already contain sig, info and ctx, respectively.
+#else
+ MOVW R0, 8(RSP) // sig
+ MOVD R1, 16(RSP) // info
+ MOVD R2, 24(RSP) // ctx
+#endif
+ CALL runtime·sigprofNonGo<ABIInternal>(SB)
+
+ // Restore callee-save registers.
+ RESTORE_R19_TO_R28(8*4)
+ RESTORE_F8_TO_F15(8*14)
+ RET
+
+// Called from c-abi, R0: sig, R1: info, R2: cxt
+TEXT runtime·cgoSigtramp(SB),NOSPLIT|NOFRAME,$0
+ // The stack unwinder, presumably written in C, may not be able to
+ // handle Go frame correctly. So, this function is NOFRAME, and we
+ // save/restore LR manually.
+ MOVD LR, R10
+ // Save R27, g because they will be clobbered,
+ // we need to restore them before jump to sigtramp.
+ MOVD R27, R11
+ MOVD g, R12
+
+ // If no traceback function, do usual sigtramp.
+ MOVD runtime·cgoTraceback(SB), R6
+ CBZ R6, sigtramp
+
+ // If no traceback support function, which means that
+ // runtime/cgo was not linked in, do usual sigtramp.
+ MOVD _cgo_callers(SB), R7
+ CBZ R7, sigtramp
+
+ // Figure out if we are currently in a cgo call.
+ // If not, just do usual sigtramp.
+ // first save R0, because runtime·load_g will clobber it.
+ MOVD R0, R8
+ // Set up g register.
+ CALL runtime·load_g(SB)
+ MOVD R8, R0
+
+ CBZ g, sigtrampnog // g == nil
+ MOVD g_m(g), R6
+ CBZ R6, sigtramp // g.m == nil
+ MOVW m_ncgo(R6), R7
+ CBZW R7, sigtramp // g.m.ncgo = 0
+ MOVD m_curg(R6), R8
+ CBZ R8, sigtramp // g.m.curg == nil
+ MOVD g_syscallsp(R8), R7
+ CBZ R7, sigtramp // g.m.curg.syscallsp == 0
+ MOVD m_cgoCallers(R6), R4 // R4 is the fifth arg in C calling convention.
+ CBZ R4, sigtramp // g.m.cgoCallers == nil
+ MOVW m_cgoCallersUse(R6), R8
+ CBNZW R8, sigtramp // g.m.cgoCallersUse != 0
+
+ // Jump to a function in runtime/cgo.
+ // That function, written in C, will call the user's traceback
+ // function with proper unwind info, and will then call back here.
+ // The first three arguments, and the fifth, are already in registers.
+ // Set the two remaining arguments now.
+ MOVD runtime·cgoTraceback(SB), R3
+ MOVD $runtime·sigtramp(SB), R5
+ MOVD _cgo_callers(SB), R13
+ MOVD R10, LR // restore
+ MOVD R11, R27
+ MOVD R12, g
+ B (R13)
+
+sigtramp:
+ MOVD R10, LR // restore
+ MOVD R11, R27
+ MOVD R12, g
+ B runtime·sigtramp(SB)
+
+sigtrampnog:
+ // Signal arrived on a non-Go thread. If this is SIGPROF, get a
+ // stack trace.
+ CMPW $27, R0 // 27 == SIGPROF
+ BNE sigtramp
+
+ // Lock sigprofCallersUse (cas from 0 to 1).
+ MOVW $1, R7
+ MOVD $runtime·sigprofCallersUse(SB), R8
+load_store_loop:
+ LDAXRW (R8), R9
+ CBNZW R9, sigtramp // Skip stack trace if already locked.
+ STLXRW R7, (R8), R9
+ CBNZ R9, load_store_loop
+
+ // Jump to the traceback function in runtime/cgo.
+ // It will call back to sigprofNonGo, which will ignore the
+ // arguments passed in registers.
+ // First three arguments to traceback function are in registers already.
+ MOVD runtime·cgoTraceback(SB), R3
+ MOVD $runtime·sigprofCallers(SB), R4
+ MOVD $runtime·sigprofNonGoWrapper<>(SB), R5
+ MOVD _cgo_callers(SB), R13
+ MOVD R10, LR // restore
+ MOVD R11, R27
+ MOVD R12, g
+ B (R13)
+
+TEXT runtime·sysMmap(SB),NOSPLIT|NOFRAME,$0
+ MOVD addr+0(FP), R0
+ MOVD n+8(FP), R1
+ MOVW prot+16(FP), R2
+ MOVW flags+20(FP), R3
+ MOVW fd+24(FP), R4
+ MOVW off+28(FP), R5
+
+ MOVD $SYS_mmap, R8
+ SVC
+ CMN $4095, R0
+ BCC ok
+ NEG R0,R0
+ MOVD $0, p+32(FP)
+ MOVD R0, err+40(FP)
+ RET
+ok:
+ MOVD R0, p+32(FP)
+ MOVD $0, err+40(FP)
+ RET
+
+// Call the function stored in _cgo_mmap using the GCC calling convention.
+// This must be called on the system stack.
+TEXT runtime·callCgoMmap(SB),NOSPLIT,$0
+ MOVD addr+0(FP), R0
+ MOVD n+8(FP), R1
+ MOVW prot+16(FP), R2
+ MOVW flags+20(FP), R3
+ MOVW fd+24(FP), R4
+ MOVW off+28(FP), R5
+ MOVD _cgo_mmap(SB), R9
+ SUB $16, RSP // reserve 16 bytes for sp-8 where fp may be saved.
+ BL R9
+ ADD $16, RSP
+ MOVD R0, ret+32(FP)
+ RET
+
+TEXT runtime·sysMunmap(SB),NOSPLIT|NOFRAME,$0
+ MOVD addr+0(FP), R0
+ MOVD n+8(FP), R1
+ MOVD $SYS_munmap, R8
+ SVC
+ CMN $4095, R0
+ BCC cool
+ MOVD R0, 0xf0(R0)
+cool:
+ RET
+
+// Call the function stored in _cgo_munmap using the GCC calling convention.
+// This must be called on the system stack.
+TEXT runtime·callCgoMunmap(SB),NOSPLIT,$0
+ MOVD addr+0(FP), R0
+ MOVD n+8(FP), R1
+ MOVD _cgo_munmap(SB), R9
+ SUB $16, RSP // reserve 16 bytes for sp-8 where fp may be saved.
+ BL R9
+ ADD $16, RSP
+ RET
+
+TEXT runtime·madvise(SB),NOSPLIT|NOFRAME,$0
+ MOVD addr+0(FP), R0
+ MOVD n+8(FP), R1
+ MOVW flags+16(FP), R2
+ MOVD $SYS_madvise, R8
+ SVC
+ MOVW R0, ret+24(FP)
+ RET
+
+// int64 futex(int32 *uaddr, int32 op, int32 val,
+// struct timespec *timeout, int32 *uaddr2, int32 val2);
+TEXT runtime·futex(SB),NOSPLIT|NOFRAME,$0
+ MOVD addr+0(FP), R0
+ MOVW op+8(FP), R1
+ MOVW val+12(FP), R2
+ MOVD ts+16(FP), R3
+ MOVD addr2+24(FP), R4
+ MOVW val3+32(FP), R5
+ MOVD $SYS_futex, R8
+ SVC
+ MOVW R0, ret+40(FP)
+ RET
+
+// int64 clone(int32 flags, void *stk, M *mp, G *gp, void (*fn)(void));
+TEXT runtime·clone(SB),NOSPLIT|NOFRAME,$0
+ MOVW flags+0(FP), R0
+ MOVD stk+8(FP), R1
+
+ // Copy mp, gp, fn off parent stack for use by child.
+ MOVD mp+16(FP), R10
+ MOVD gp+24(FP), R11
+ MOVD fn+32(FP), R12
+
+ MOVD R10, -8(R1)
+ MOVD R11, -16(R1)
+ MOVD R12, -24(R1)
+ MOVD $1234, R10
+ MOVD R10, -32(R1)
+
+ MOVD $SYS_clone, R8
+ SVC
+
+ // In parent, return.
+ CMP ZR, R0
+ BEQ child
+ MOVW R0, ret+40(FP)
+ RET
+child:
+
+ // In child, on new stack.
+ MOVD -32(RSP), R10
+ MOVD $1234, R0
+ CMP R0, R10
+ BEQ good
+ MOVD $0, R0
+ MOVD R0, (R0) // crash
+
+good:
+ // Initialize m->procid to Linux tid
+ MOVD $SYS_gettid, R8
+ SVC
+
+ MOVD -24(RSP), R12 // fn
+ MOVD -16(RSP), R11 // g
+ MOVD -8(RSP), R10 // m
+
+ CMP $0, R10
+ BEQ nog
+ CMP $0, R11
+ BEQ nog
+
+ MOVD R0, m_procid(R10)
+
+ // TODO: setup TLS.
+
+ // In child, set up new stack
+ MOVD R10, g_m(R11)
+ MOVD R11, g
+ //CALL runtime·stackcheck(SB)
+
+nog:
+ // Call fn
+ MOVD R12, R0
+ BL (R0)
+
+ // It shouldn't return. If it does, exit that thread.
+ MOVW $111, R0
+again:
+ MOVD $SYS_exit, R8
+ SVC
+ B again // keep exiting
+
+TEXT runtime·sigaltstack(SB),NOSPLIT|NOFRAME,$0
+ MOVD new+0(FP), R0
+ MOVD old+8(FP), R1
+ MOVD $SYS_sigaltstack, R8
+ SVC
+ CMN $4095, R0
+ BCC ok
+ MOVD $0, R0
+ MOVD R0, (R0) // crash
+ok:
+ RET
+
+TEXT runtime·osyield(SB),NOSPLIT|NOFRAME,$0
+ MOVD $SYS_sched_yield, R8
+ SVC
+ RET
+
+TEXT runtime·sched_getaffinity(SB),NOSPLIT|NOFRAME,$0
+ MOVD pid+0(FP), R0
+ MOVD len+8(FP), R1
+ MOVD buf+16(FP), R2
+ MOVD $SYS_sched_getaffinity, R8
+ SVC
+ MOVW R0, ret+24(FP)
+ RET
+
+// int access(const char *name, int mode)
+TEXT runtime·access(SB),NOSPLIT,$0-20
+ MOVD $AT_FDCWD, R0
+ MOVD name+0(FP), R1
+ MOVW mode+8(FP), R2
+ MOVD $SYS_faccessat, R8
+ SVC
+ MOVW R0, ret+16(FP)
+ RET
+
+// int connect(int fd, const struct sockaddr *addr, socklen_t len)
+TEXT runtime·connect(SB),NOSPLIT,$0-28
+ MOVW fd+0(FP), R0
+ MOVD addr+8(FP), R1
+ MOVW len+16(FP), R2
+ MOVD $SYS_connect, R8
+ SVC
+ MOVW R0, ret+24(FP)
+ RET
+
+// int socket(int domain, int typ, int prot)
+TEXT runtime·socket(SB),NOSPLIT,$0-20
+ MOVW domain+0(FP), R0
+ MOVW typ+4(FP), R1
+ MOVW prot+8(FP), R2
+ MOVD $SYS_socket, R8
+ SVC
+ MOVW R0, ret+16(FP)
+ RET
+
+// func sbrk0() uintptr
+TEXT runtime·sbrk0(SB),NOSPLIT,$0-8
+ // Implemented as brk(NULL).
+ MOVD $0, R0
+ MOVD $SYS_brk, R8
+ SVC
+ MOVD R0, ret+0(FP)
+ RET
+
+TEXT runtime·sigreturn(SB),NOSPLIT,$0-0
+ RET