...

Text file src/runtime/sys_linux_amd64.s

Documentation: runtime

     1// Copyright 2009 The Go Authors. All rights reserved.
     2// Use of this source code is governed by a BSD-style
     3// license that can be found in the LICENSE file.
     4
     5//
     6// System calls and other sys.stuff for AMD64, Linux
     7//
     8
     9#include "go_asm.h"
    10#include "go_tls.h"
    11#include "textflag.h"
    12#include "cgo/abi_amd64.h"
    13
    14#define AT_FDCWD -100
    15
    16#define SYS_read		0
    17#define SYS_write		1
    18#define SYS_close		3
    19#define SYS_mmap		9
    20#define SYS_munmap		11
    21#define SYS_brk 		12
    22#define SYS_rt_sigaction	13
    23#define SYS_rt_sigprocmask	14
    24#define SYS_rt_sigreturn	15
    25#define SYS_sched_yield 	24
    26#define SYS_mincore		27
    27#define SYS_madvise		28
    28#define SYS_nanosleep		35
    29#define SYS_setittimer		38
    30#define SYS_getpid		39
    31#define SYS_socket		41
    32#define SYS_connect		42
    33#define SYS_clone		56
    34#define SYS_exit		60
    35#define SYS_kill		62
    36#define SYS_sigaltstack 	131
    37#define SYS_arch_prctl		158
    38#define SYS_gettid		186
    39#define SYS_futex		202
    40#define SYS_sched_getaffinity	204
    41#define SYS_timer_create	222
    42#define SYS_timer_settime	223
    43#define SYS_timer_delete	226
    44#define SYS_clock_gettime	228
    45#define SYS_exit_group		231
    46#define SYS_tgkill		234
    47#define SYS_openat		257
    48#define SYS_faccessat		269
    49#define SYS_pipe2		293
    50
    51TEXT runtime·exit(SB),NOSPLIT,$0-4
    52	MOVL	code+0(FP), DI
    53	MOVL	$SYS_exit_group, AX
    54	SYSCALL
    55	RET
    56
    57// func exitThread(wait *atomic.Uint32)
    58TEXT runtime·exitThread(SB),NOSPLIT,$0-8
    59	MOVQ	wait+0(FP), AX
    60	// We're done using the stack.
    61	MOVL	$0, (AX)
    62	MOVL	$0, DI	// exit code
    63	MOVL	$SYS_exit, AX
    64	SYSCALL
    65	// We may not even have a stack any more.
    66	INT	$3
    67	JMP	0(PC)
    68
    69TEXT runtime·open(SB),NOSPLIT,$0-20
    70	// This uses openat instead of open, because Android O blocks open.
    71	MOVL	$AT_FDCWD, DI // AT_FDCWD, so this acts like open
    72	MOVQ	name+0(FP), SI
    73	MOVL	mode+8(FP), DX
    74	MOVL	perm+12(FP), R10
    75	MOVL	$SYS_openat, AX
    76	SYSCALL
    77	CMPQ	AX, $0xfffffffffffff001
    78	JLS	2(PC)
    79	MOVL	$-1, AX
    80	MOVL	AX, ret+16(FP)
    81	RET
    82
    83TEXT runtime·closefd(SB),NOSPLIT,$0-12
    84	MOVL	fd+0(FP), DI
    85	MOVL	$SYS_close, AX
    86	SYSCALL
    87	CMPQ	AX, $0xfffffffffffff001
    88	JLS	2(PC)
    89	MOVL	$-1, AX
    90	MOVL	AX, ret+8(FP)
    91	RET
    92
    93TEXT runtime·write1(SB),NOSPLIT,$0-28
    94	MOVQ	fd+0(FP), DI
    95	MOVQ	p+8(FP), SI
    96	MOVL	n+16(FP), DX
    97	MOVL	$SYS_write, AX
    98	SYSCALL
    99	MOVL	AX, ret+24(FP)
   100	RET
   101
   102TEXT runtime·read(SB),NOSPLIT,$0-28
   103	MOVL	fd+0(FP), DI
   104	MOVQ	p+8(FP), SI
   105	MOVL	n+16(FP), DX
   106	MOVL	$SYS_read, AX
   107	SYSCALL
   108	MOVL	AX, ret+24(FP)
   109	RET
   110
   111// func pipe2(flags int32) (r, w int32, errno int32)
   112TEXT runtime·pipe2(SB),NOSPLIT,$0-20
   113	LEAQ	r+8(FP), DI
   114	MOVL	flags+0(FP), SI
   115	MOVL	$SYS_pipe2, AX
   116	SYSCALL
   117	MOVL	AX, errno+16(FP)
   118	RET
   119
   120TEXT runtime·usleep(SB),NOSPLIT,$16
   121	MOVL	$0, DX
   122	MOVL	usec+0(FP), AX
   123	MOVL	$1000000, CX
   124	DIVL	CX
   125	MOVQ	AX, 0(SP)
   126	MOVL	$1000, AX	// usec to nsec
   127	MULL	DX
   128	MOVQ	AX, 8(SP)
   129
   130	// nanosleep(&ts, 0)
   131	MOVQ	SP, DI
   132	MOVL	$0, SI
   133	MOVL	$SYS_nanosleep, AX
   134	SYSCALL
   135	RET
   136
   137TEXT runtime·gettid(SB),NOSPLIT,$0-4
   138	MOVL	$SYS_gettid, AX
   139	SYSCALL
   140	MOVL	AX, ret+0(FP)
   141	RET
   142
   143TEXT runtime·raise(SB),NOSPLIT,$0
   144	MOVL	$SYS_getpid, AX
   145	SYSCALL
   146	MOVL	AX, R12
   147	MOVL	$SYS_gettid, AX
   148	SYSCALL
   149	MOVL	AX, SI	// arg 2 tid
   150	MOVL	R12, DI	// arg 1 pid
   151	MOVL	sig+0(FP), DX	// arg 3
   152	MOVL	$SYS_tgkill, AX
   153	SYSCALL
   154	RET
   155
   156TEXT runtime·raiseproc(SB),NOSPLIT,$0
   157	MOVL	$SYS_getpid, AX
   158	SYSCALL
   159	MOVL	AX, DI	// arg 1 pid
   160	MOVL	sig+0(FP), SI	// arg 2
   161	MOVL	$SYS_kill, AX
   162	SYSCALL
   163	RET
   164
   165TEXT ·getpid(SB),NOSPLIT,$0-8
   166	MOVL	$SYS_getpid, AX
   167	SYSCALL
   168	MOVQ	AX, ret+0(FP)
   169	RET
   170
   171TEXT ·tgkill(SB),NOSPLIT,$0
   172	MOVQ	tgid+0(FP), DI
   173	MOVQ	tid+8(FP), SI
   174	MOVQ	sig+16(FP), DX
   175	MOVL	$SYS_tgkill, AX
   176	SYSCALL
   177	RET
   178
   179TEXT runtime·setitimer(SB),NOSPLIT,$0-24
   180	MOVL	mode+0(FP), DI
   181	MOVQ	new+8(FP), SI
   182	MOVQ	old+16(FP), DX
   183	MOVL	$SYS_setittimer, AX
   184	SYSCALL
   185	RET
   186
   187TEXT runtime·timer_create(SB),NOSPLIT,$0-28
   188	MOVL	clockid+0(FP), DI
   189	MOVQ	sevp+8(FP), SI
   190	MOVQ	timerid+16(FP), DX
   191	MOVL	$SYS_timer_create, AX
   192	SYSCALL
   193	MOVL	AX, ret+24(FP)
   194	RET
   195
   196TEXT runtime·timer_settime(SB),NOSPLIT,$0-28
   197	MOVL	timerid+0(FP), DI
   198	MOVL	flags+4(FP), SI
   199	MOVQ	new+8(FP), DX
   200	MOVQ	old+16(FP), R10
   201	MOVL	$SYS_timer_settime, AX
   202	SYSCALL
   203	MOVL	AX, ret+24(FP)
   204	RET
   205
   206TEXT runtime·timer_delete(SB),NOSPLIT,$0-12
   207	MOVL	timerid+0(FP), DI
   208	MOVL	$SYS_timer_delete, AX
   209	SYSCALL
   210	MOVL	AX, ret+8(FP)
   211	RET
   212
   213TEXT runtime·mincore(SB),NOSPLIT,$0-28
   214	MOVQ	addr+0(FP), DI
   215	MOVQ	n+8(FP), SI
   216	MOVQ	dst+16(FP), DX
   217	MOVL	$SYS_mincore, AX
   218	SYSCALL
   219	MOVL	AX, ret+24(FP)
   220	RET
   221
   222// func nanotime1() int64
   223TEXT runtime·nanotime1(SB),NOSPLIT,$16-8
   224	// We don't know how much stack space the VDSO code will need,
   225	// so switch to g0.
   226	// In particular, a kernel configured with CONFIG_OPTIMIZE_INLINING=n
   227	// and hardening can use a full page of stack space in gettime_sym
   228	// due to stack probes inserted to avoid stack/heap collisions.
   229	// See issue #20427.
   230
   231	MOVQ	SP, R12	// Save old SP; R12 unchanged by C code.
   232
   233	MOVQ	g_m(R14), BX // BX unchanged by C code.
   234
   235	// Set vdsoPC and vdsoSP for SIGPROF traceback.
   236	// Save the old values on stack and restore them on exit,
   237	// so this function is reentrant.
   238	MOVQ	m_vdsoPC(BX), CX
   239	MOVQ	m_vdsoSP(BX), DX
   240	MOVQ	CX, 0(SP)
   241	MOVQ	DX, 8(SP)
   242
   243	LEAQ	ret+0(FP), DX
   244	MOVQ	-8(DX), CX
   245	MOVQ	CX, m_vdsoPC(BX)
   246	MOVQ	DX, m_vdsoSP(BX)
   247
   248	CMPQ	R14, m_curg(BX)	// Only switch if on curg.
   249	JNE	noswitch
   250
   251	MOVQ	m_g0(BX), DX
   252	MOVQ	(g_sched+gobuf_sp)(DX), SP	// Set SP to g0 stack
   253
   254noswitch:
   255	SUBQ	$16, SP		// Space for results
   256	ANDQ	$~15, SP	// Align for C code
   257
   258	MOVL	$1, DI // CLOCK_MONOTONIC
   259	LEAQ	0(SP), SI
   260	MOVQ	runtime·vdsoClockgettimeSym(SB), AX
   261	CMPQ	AX, $0
   262	JEQ	fallback
   263	CALL	AX
   264ret:
   265	MOVQ	0(SP), AX	// sec
   266	MOVQ	8(SP), DX	// nsec
   267	MOVQ	R12, SP		// Restore real SP
   268	// Restore vdsoPC, vdsoSP
   269	// We don't worry about being signaled between the two stores.
   270	// If we are not in a signal handler, we'll restore vdsoSP to 0,
   271	// and no one will care about vdsoPC. If we are in a signal handler,
   272	// we cannot receive another signal.
   273	MOVQ	8(SP), CX
   274	MOVQ	CX, m_vdsoSP(BX)
   275	MOVQ	0(SP), CX
   276	MOVQ	CX, m_vdsoPC(BX)
   277	// sec is in AX, nsec in DX
   278	// return nsec in AX
   279	IMULQ	$1000000000, AX
   280	ADDQ	DX, AX
   281	MOVQ	AX, ret+0(FP)
   282	RET
   283fallback:
   284	MOVQ	$SYS_clock_gettime, AX
   285	SYSCALL
   286	JMP	ret
   287
   288TEXT runtime·rtsigprocmask(SB),NOSPLIT,$0-28
   289	MOVL	how+0(FP), DI
   290	MOVQ	new+8(FP), SI
   291	MOVQ	old+16(FP), DX
   292	MOVL	size+24(FP), R10
   293	MOVL	$SYS_rt_sigprocmask, AX
   294	SYSCALL
   295	CMPQ	AX, $0xfffffffffffff001
   296	JLS	2(PC)
   297	MOVL	$0xf1, 0xf1  // crash
   298	RET
   299
   300TEXT runtime·rt_sigaction(SB),NOSPLIT,$0-36
   301	MOVQ	sig+0(FP), DI
   302	MOVQ	new+8(FP), SI
   303	MOVQ	old+16(FP), DX
   304	MOVQ	size+24(FP), R10
   305	MOVL	$SYS_rt_sigaction, AX
   306	SYSCALL
   307	MOVL	AX, ret+32(FP)
   308	RET
   309
   310// Call the function stored in _cgo_sigaction using the GCC calling convention.
   311TEXT runtime·callCgoSigaction(SB),NOSPLIT,$16
   312	MOVQ	sig+0(FP), DI
   313	MOVQ	new+8(FP), SI
   314	MOVQ	old+16(FP), DX
   315	MOVQ	_cgo_sigaction(SB), AX
   316	MOVQ	SP, BX	// callee-saved
   317	ANDQ	$~15, SP	// alignment as per amd64 psABI
   318	CALL	AX
   319	MOVQ	BX, SP
   320	MOVL	AX, ret+24(FP)
   321	RET
   322
   323TEXT runtime·sigfwd(SB),NOSPLIT,$0-32
   324	MOVQ	fn+0(FP),    AX
   325	MOVL	sig+8(FP),   DI
   326	MOVQ	info+16(FP), SI
   327	MOVQ	ctx+24(FP),  DX
   328	MOVQ	SP, BX		// callee-saved
   329	ANDQ	$~15, SP     // alignment for x86_64 ABI
   330	CALL	AX
   331	MOVQ	BX, SP
   332	RET
   333
   334// Called using C ABI.
   335TEXT runtime·sigtramp(SB),NOSPLIT|TOPFRAME|NOFRAME,$0
   336	// Transition from C ABI to Go ABI.
   337	PUSH_REGS_HOST_TO_ABI0()
   338
   339	// Set up ABIInternal environment: g in R14, cleared X15.
   340	get_tls(R12)
   341	MOVQ	g(R12), R14
   342	PXOR	X15, X15
   343
   344	// Reserve space for spill slots.
   345	NOP	SP		// disable vet stack checking
   346	ADJSP   $24
   347
   348	// Call into the Go signal handler
   349	MOVQ	DI, AX	// sig
   350	MOVQ	SI, BX	// info
   351	MOVQ	DX, CX	// ctx
   352	CALL	·sigtrampgo<ABIInternal>(SB)
   353
   354	ADJSP	$-24
   355
   356	POP_REGS_HOST_TO_ABI0()
   357	RET
   358
   359// Called using C ABI.
   360TEXT runtime·sigprofNonGoWrapper<>(SB),NOSPLIT|NOFRAME,$0
   361	// Transition from C ABI to Go ABI.
   362	PUSH_REGS_HOST_TO_ABI0()
   363
   364	// Set up ABIInternal environment: g in R14, cleared X15.
   365	get_tls(R12)
   366	MOVQ	g(R12), R14
   367	PXOR	X15, X15
   368
   369	// Reserve space for spill slots.
   370	NOP	SP		// disable vet stack checking
   371	ADJSP   $24
   372
   373	// Call into the Go signal handler
   374	MOVQ	DI, AX	// sig
   375	MOVQ	SI, BX	// info
   376	MOVQ	DX, CX	// ctx
   377	CALL	·sigprofNonGo<ABIInternal>(SB)
   378
   379	ADJSP	$-24
   380
   381	POP_REGS_HOST_TO_ABI0()
   382	RET
   383
   384// Used instead of sigtramp in programs that use cgo.
   385// Arguments from kernel are in DI, SI, DX.
   386TEXT runtime·cgoSigtramp(SB),NOSPLIT,$0
   387	// If no traceback function, do usual sigtramp.
   388	MOVQ	runtime·cgoTraceback(SB), AX
   389	TESTQ	AX, AX
   390	JZ	sigtramp
   391
   392	// If no traceback support function, which means that
   393	// runtime/cgo was not linked in, do usual sigtramp.
   394	MOVQ	_cgo_callers(SB), AX
   395	TESTQ	AX, AX
   396	JZ	sigtramp
   397
   398	// Figure out if we are currently in a cgo call.
   399	// If not, just do usual sigtramp.
   400	get_tls(CX)
   401	MOVQ	g(CX),AX
   402	TESTQ	AX, AX
   403	JZ	sigtrampnog     // g == nil
   404	MOVQ	g_m(AX), AX
   405	TESTQ	AX, AX
   406	JZ	sigtramp        // g.m == nil
   407	MOVL	m_ncgo(AX), CX
   408	TESTL	CX, CX
   409	JZ	sigtramp        // g.m.ncgo == 0
   410	MOVQ	m_curg(AX), CX
   411	TESTQ	CX, CX
   412	JZ	sigtramp        // g.m.curg == nil
   413	MOVQ	g_syscallsp(CX), CX
   414	TESTQ	CX, CX
   415	JZ	sigtramp        // g.m.curg.syscallsp == 0
   416	MOVQ	m_cgoCallers(AX), R8
   417	TESTQ	R8, R8
   418	JZ	sigtramp        // g.m.cgoCallers == nil
   419	MOVL	m_cgoCallersUse(AX), CX
   420	TESTL	CX, CX
   421	JNZ	sigtramp	// g.m.cgoCallersUse != 0
   422
   423	// Jump to a function in runtime/cgo.
   424	// That function, written in C, will call the user's traceback
   425	// function with proper unwind info, and will then call back here.
   426	// The first three arguments, and the fifth, are already in registers.
   427	// Set the two remaining arguments now.
   428	MOVQ	runtime·cgoTraceback(SB), CX
   429	MOVQ	$runtime·sigtramp(SB), R9
   430	MOVQ	_cgo_callers(SB), AX
   431	JMP	AX
   432
   433sigtramp:
   434	JMP	runtime·sigtramp(SB)
   435
   436sigtrampnog:
   437	// Signal arrived on a non-Go thread. If this is SIGPROF, get a
   438	// stack trace.
   439	CMPL	DI, $27 // 27 == SIGPROF
   440	JNZ	sigtramp
   441
   442	// Lock sigprofCallersUse.
   443	MOVL	$0, AX
   444	MOVL	$1, CX
   445	MOVQ	$runtime·sigprofCallersUse(SB), R11
   446	LOCK
   447	CMPXCHGL	CX, 0(R11)
   448	JNZ	sigtramp  // Skip stack trace if already locked.
   449
   450	// Jump to the traceback function in runtime/cgo.
   451	// It will call back to sigprofNonGo, via sigprofNonGoWrapper, to convert
   452	// the arguments to the Go calling convention.
   453	// First three arguments to traceback function are in registers already.
   454	MOVQ	runtime·cgoTraceback(SB), CX
   455	MOVQ	$runtime·sigprofCallers(SB), R8
   456	MOVQ	$runtime·sigprofNonGoWrapper<>(SB), R9
   457	MOVQ	_cgo_callers(SB), AX
   458	JMP	AX
   459
   460// For cgo unwinding to work, this function must look precisely like
   461// the one in glibc. The glibc source code is:
   462// https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/x86_64/libc_sigaction.c;h=afdce87381228f0cf32fa9fa6c8c4efa5179065c#l80
   463// The code that cares about the precise instructions used is:
   464// https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=libgcc/config/i386/linux-unwind.h;h=5486223d60272c73d5103b29ae592d2ee998e1cf#l49
   465//
   466// For gdb unwinding to work, this function must look precisely like the one in
   467// glibc and must be named "__restore_rt" or contain the string "sigaction" in
   468// the name. The gdb source code is:
   469// https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=gdb/amd64-linux-tdep.c;h=cbbac1a0c64e1deb8181b9d0ff6404e328e2979d#l178
   470TEXT runtime·sigreturn__sigaction(SB),NOSPLIT,$0
   471	MOVQ	$SYS_rt_sigreturn, AX
   472	SYSCALL
   473	INT $3	// not reached
   474
   475TEXT runtime·sysMmap(SB),NOSPLIT,$0
   476	MOVQ	addr+0(FP), DI
   477	MOVQ	n+8(FP), SI
   478	MOVL	prot+16(FP), DX
   479	MOVL	flags+20(FP), R10
   480	MOVL	fd+24(FP), R8
   481	MOVL	off+28(FP), R9
   482
   483	MOVL	$SYS_mmap, AX
   484	SYSCALL
   485	CMPQ	AX, $0xfffffffffffff001
   486	JLS	ok
   487	NOTQ	AX
   488	INCQ	AX
   489	MOVQ	$0, p+32(FP)
   490	MOVQ	AX, err+40(FP)
   491	RET
   492ok:
   493	MOVQ	AX, p+32(FP)
   494	MOVQ	$0, err+40(FP)
   495	RET
   496
   497// Call the function stored in _cgo_mmap using the GCC calling convention.
   498// This must be called on the system stack.
   499TEXT runtime·callCgoMmap(SB),NOSPLIT,$16
   500	MOVQ	addr+0(FP), DI
   501	MOVQ	n+8(FP), SI
   502	MOVL	prot+16(FP), DX
   503	MOVL	flags+20(FP), CX
   504	MOVL	fd+24(FP), R8
   505	MOVL	off+28(FP), R9
   506	MOVQ	_cgo_mmap(SB), AX
   507	MOVQ	SP, BX
   508	ANDQ	$~15, SP	// alignment as per amd64 psABI
   509	MOVQ	BX, 0(SP)
   510	CALL	AX
   511	MOVQ	0(SP), SP
   512	MOVQ	AX, ret+32(FP)
   513	RET
   514
   515TEXT runtime·sysMunmap(SB),NOSPLIT,$0
   516	MOVQ	addr+0(FP), DI
   517	MOVQ	n+8(FP), SI
   518	MOVQ	$SYS_munmap, AX
   519	SYSCALL
   520	CMPQ	AX, $0xfffffffffffff001
   521	JLS	2(PC)
   522	MOVL	$0xf1, 0xf1  // crash
   523	RET
   524
   525// Call the function stored in _cgo_munmap using the GCC calling convention.
   526// This must be called on the system stack.
   527TEXT runtime·callCgoMunmap(SB),NOSPLIT,$16-16
   528	MOVQ	addr+0(FP), DI
   529	MOVQ	n+8(FP), SI
   530	MOVQ	_cgo_munmap(SB), AX
   531	MOVQ	SP, BX
   532	ANDQ	$~15, SP	// alignment as per amd64 psABI
   533	MOVQ	BX, 0(SP)
   534	CALL	AX
   535	MOVQ	0(SP), SP
   536	RET
   537
   538TEXT runtime·madvise(SB),NOSPLIT,$0
   539	MOVQ	addr+0(FP), DI
   540	MOVQ	n+8(FP), SI
   541	MOVL	flags+16(FP), DX
   542	MOVQ	$SYS_madvise, AX
   543	SYSCALL
   544	MOVL	AX, ret+24(FP)
   545	RET
   546
   547// int64 futex(int32 *uaddr, int32 op, int32 val,
   548//	struct timespec *timeout, int32 *uaddr2, int32 val2);
   549TEXT runtime·futex(SB),NOSPLIT,$0
   550	MOVQ	addr+0(FP), DI
   551	MOVL	op+8(FP), SI
   552	MOVL	val+12(FP), DX
   553	MOVQ	ts+16(FP), R10
   554	MOVQ	addr2+24(FP), R8
   555	MOVL	val3+32(FP), R9
   556	MOVL	$SYS_futex, AX
   557	SYSCALL
   558	MOVL	AX, ret+40(FP)
   559	RET
   560
   561// int32 clone(int32 flags, void *stk, M *mp, G *gp, void (*fn)(void));
   562TEXT runtime·clone(SB),NOSPLIT|NOFRAME,$0
   563	MOVL	flags+0(FP), DI
   564	MOVQ	stk+8(FP), SI
   565	MOVQ	$0, DX
   566	MOVQ	$0, R10
   567	MOVQ    $0, R8
   568	// Copy mp, gp, fn off parent stack for use by child.
   569	// Careful: Linux system call clobbers CX and R11.
   570	MOVQ	mp+16(FP), R13
   571	MOVQ	gp+24(FP), R9
   572	MOVQ	fn+32(FP), R12
   573	CMPQ	R13, $0    // m
   574	JEQ	nog1
   575	CMPQ	R9, $0    // g
   576	JEQ	nog1
   577	LEAQ	m_tls(R13), R8
   578#ifdef GOOS_android
   579	// Android stores the TLS offset in runtime·tls_g.
   580	SUBQ	runtime·tls_g(SB), R8
   581#else
   582	ADDQ	$8, R8	// ELF wants to use -8(FS)
   583#endif
   584	ORQ 	$0x00080000, DI //add flag CLONE_SETTLS(0x00080000) to call clone
   585nog1:
   586	MOVL	$SYS_clone, AX
   587	SYSCALL
   588
   589	// In parent, return.
   590	CMPQ	AX, $0
   591	JEQ	3(PC)
   592	MOVL	AX, ret+40(FP)
   593	RET
   594
   595	// In child, on new stack.
   596	MOVQ	SI, SP
   597
   598	// If g or m are nil, skip Go-related setup.
   599	CMPQ	R13, $0    // m
   600	JEQ	nog2
   601	CMPQ	R9, $0    // g
   602	JEQ	nog2
   603
   604	// Initialize m->procid to Linux tid
   605	MOVL	$SYS_gettid, AX
   606	SYSCALL
   607	MOVQ	AX, m_procid(R13)
   608
   609	// In child, set up new stack
   610	get_tls(CX)
   611	MOVQ	R13, g_m(R9)
   612	MOVQ	R9, g(CX)
   613	MOVQ	R9, R14 // set g register
   614	CALL	runtime·stackcheck(SB)
   615
   616nog2:
   617	// Call fn. This is the PC of an ABI0 function.
   618	CALL	R12
   619
   620	// It shouldn't return. If it does, exit that thread.
   621	MOVL	$111, DI
   622	MOVL	$SYS_exit, AX
   623	SYSCALL
   624	JMP	-3(PC)	// keep exiting
   625
   626TEXT runtime·sigaltstack(SB),NOSPLIT,$0
   627	MOVQ	new+0(FP), DI
   628	MOVQ	old+8(FP), SI
   629	MOVQ	$SYS_sigaltstack, AX
   630	SYSCALL
   631	CMPQ	AX, $0xfffffffffffff001
   632	JLS	2(PC)
   633	MOVL	$0xf1, 0xf1  // crash
   634	RET
   635
   636// set tls base to DI
   637TEXT runtime·settls(SB),NOSPLIT,$32
   638#ifdef GOOS_android
   639	// Android stores the TLS offset in runtime·tls_g.
   640	SUBQ	runtime·tls_g(SB), DI
   641#else
   642	ADDQ	$8, DI	// ELF wants to use -8(FS)
   643#endif
   644	MOVQ	DI, SI
   645	MOVQ	$0x1002, DI	// ARCH_SET_FS
   646	MOVQ	$SYS_arch_prctl, AX
   647	SYSCALL
   648	CMPQ	AX, $0xfffffffffffff001
   649	JLS	2(PC)
   650	MOVL	$0xf1, 0xf1  // crash
   651	RET
   652
   653TEXT runtime·osyield(SB),NOSPLIT,$0
   654	MOVL	$SYS_sched_yield, AX
   655	SYSCALL
   656	RET
   657
   658TEXT runtime·sched_getaffinity(SB),NOSPLIT,$0
   659	MOVQ	pid+0(FP), DI
   660	MOVQ	len+8(FP), SI
   661	MOVQ	buf+16(FP), DX
   662	MOVL	$SYS_sched_getaffinity, AX
   663	SYSCALL
   664	MOVL	AX, ret+24(FP)
   665	RET
   666
   667// int access(const char *name, int mode)
   668TEXT runtime·access(SB),NOSPLIT,$0
   669	// This uses faccessat instead of access, because Android O blocks access.
   670	MOVL	$AT_FDCWD, DI // AT_FDCWD, so this acts like access
   671	MOVQ	name+0(FP), SI
   672	MOVL	mode+8(FP), DX
   673	MOVL	$0, R10
   674	MOVL	$SYS_faccessat, AX
   675	SYSCALL
   676	MOVL	AX, ret+16(FP)
   677	RET
   678
   679// int connect(int fd, const struct sockaddr *addr, socklen_t addrlen)
   680TEXT runtime·connect(SB),NOSPLIT,$0-28
   681	MOVL	fd+0(FP), DI
   682	MOVQ	addr+8(FP), SI
   683	MOVL	len+16(FP), DX
   684	MOVL	$SYS_connect, AX
   685	SYSCALL
   686	MOVL	AX, ret+24(FP)
   687	RET
   688
   689// int socket(int domain, int type, int protocol)
   690TEXT runtime·socket(SB),NOSPLIT,$0-20
   691	MOVL	domain+0(FP), DI
   692	MOVL	typ+4(FP), SI
   693	MOVL	prot+8(FP), DX
   694	MOVL	$SYS_socket, AX
   695	SYSCALL
   696	MOVL	AX, ret+16(FP)
   697	RET
   698
   699// func sbrk0() uintptr
   700TEXT runtime·sbrk0(SB),NOSPLIT,$0-8
   701	// Implemented as brk(NULL).
   702	MOVQ	$0, DI
   703	MOVL	$SYS_brk, AX
   704	SYSCALL
   705	MOVQ	AX, ret+0(FP)
   706	RET

View as plain text