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// Copyright 2009 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.
#include "amd64/asm.h"
TEXT _rt0_amd64(SB),7,$-8
// copy arguments forward on an even stack
MOVQ 0(DI), AX // argc
LEAQ 8(DI), BX // argv
SUBQ $(4*8+7), SP // 2args 2auto
ANDQ $~15, SP
MOVQ AX, 16(SP)
MOVQ BX, 24(SP)
// if there is an initcgo, call it.
MOVQ initcgo(SB), AX
TESTQ AX, AX
JZ needtls
CALL AX
JMP ok
needtls:
LEAQ runtime·tls0(SB), DI
CALL runtime·settls(SB)
// store through it, to make sure it works
get_tls(BX)
MOVQ $0x123, g(BX)
MOVQ runtime·tls0(SB), AX
CMPQ AX, $0x123
JEQ 2(PC)
MOVL AX, 0 // abort
ok:
// set the per-goroutine and per-mach "registers"
get_tls(BX)
LEAQ runtime·g0(SB), CX
MOVQ CX, g(BX)
LEAQ runtime·m0(SB), AX
MOVQ AX, m(BX)
// save m->g0 = g0
MOVQ CX, m_g0(AX)
// create istack out of the given (operating system) stack
LEAQ (-8192+104)(SP), AX
MOVQ AX, g_stackguard(CX)
MOVQ SP, g_stackbase(CX)
CLD // convention is D is always left cleared
CALL runtime·check(SB)
MOVL 16(SP), AX // copy argc
MOVL AX, 0(SP)
MOVQ 24(SP), AX // copy argv
MOVQ AX, 8(SP)
CALL runtime·args(SB)
CALL runtime·osinit(SB)
CALL runtime·schedinit(SB)
// create a new goroutine to start program
PUSHQ $runtime·mainstart(SB) // entry
PUSHQ $0 // arg size
CALL runtime·newproc(SB)
POPQ AX
POPQ AX
// start this M
CALL runtime·mstart(SB)
CALL runtime·notok(SB) // never returns
RET
TEXT runtime·mainstart(SB),7,$0
CALL main·init(SB)
CALL runtime·initdone(SB)
CALL main·main(SB)
PUSHQ $0
CALL runtime·exit(SB)
POPQ AX
CALL runtime·notok(SB)
RET
TEXT runtime·breakpoint(SB),7,$0
BYTE $0xcc
RET
/*
* go-routine
*/
// void gosave(Gobuf*)
// save state in Gobuf; setjmp
TEXT runtime·gosave(SB), 7, $0
MOVQ 8(SP), AX // gobuf
LEAQ 8(SP), BX // caller's SP
MOVQ BX, gobuf_sp(AX)
MOVQ 0(SP), BX // caller's PC
MOVQ BX, gobuf_pc(AX)
get_tls(CX)
MOVQ g(CX), BX
MOVQ BX, gobuf_g(AX)
RET
// void gogo(Gobuf*, uintptr)
// restore state from Gobuf; longjmp
TEXT runtime·gogo(SB), 7, $0
MOVQ 16(SP), AX // return 2nd arg
MOVQ 8(SP), BX // gobuf
MOVQ gobuf_g(BX), DX
MOVQ 0(DX), CX // make sure g != nil
get_tls(CX)
MOVQ DX, g(CX)
MOVQ gobuf_sp(BX), SP // restore SP
MOVQ gobuf_pc(BX), BX
JMP BX
// void gogocall(Gobuf*, void (*fn)(void))
// restore state from Gobuf but then call fn.
// (call fn, returning to state in Gobuf)
TEXT runtime·gogocall(SB), 7, $0
MOVQ 16(SP), AX // fn
MOVQ 8(SP), BX // gobuf
MOVQ gobuf_g(BX), DX
get_tls(CX)
MOVQ DX, g(CX)
MOVQ 0(DX), CX // make sure g != nil
MOVQ gobuf_sp(BX), SP // restore SP
MOVQ gobuf_pc(BX), BX
PUSHQ BX
JMP AX
POPQ BX // not reached
// void mcall(void (*fn)(G*))
// Switch to m->g0's stack, call fn(g).
// Fn must never return. It should gogo(&g->gobuf)
// to keep running g.
TEXT runtime·mcall(SB), 7, $0
MOVQ fn+0(FP), DI
get_tls(CX)
MOVQ g(CX), AX // save state in g->gobuf
MOVQ 0(SP), BX // caller's PC
MOVQ BX, (g_sched+gobuf_pc)(AX)
LEAQ 8(SP), BX // caller's SP
MOVQ BX, (g_sched+gobuf_sp)(AX)
MOVQ AX, (g_sched+gobuf_g)(AX)
// switch to m->g0 & its stack, call fn
MOVQ m(CX), BX
MOVQ m_g0(BX), SI
CMPQ SI, AX // if g == m->g0 call badmcall
JNE 2(PC)
CALL runtime·badmcall(SB)
MOVQ SI, g(CX) // g = m->g0
MOVQ (g_sched+gobuf_sp)(SI), SP // sp = m->g0->gobuf.sp
PUSHQ AX
CALL DI
POPQ AX
CALL runtime·badmcall2(SB)
RET
/*
* support for morestack
*/
// Called during function prolog when more stack is needed.
// Caller has already done get_tls(CX); MOVQ m(CX), BX.
TEXT runtime·morestack(SB),7,$0
// Cannot grow scheduler stack (m->g0).
MOVQ m_g0(BX), SI
CMPQ g(CX), SI
JNE 2(PC)
INT $3
// Called from f.
// Set m->morebuf to f's caller.
MOVQ 8(SP), AX // f's caller's PC
MOVQ AX, (m_morebuf+gobuf_pc)(BX)
LEAQ 16(SP), AX // f's caller's SP
MOVQ AX, (m_morebuf+gobuf_sp)(BX)
MOVQ AX, m_moreargp(BX)
get_tls(CX)
MOVQ g(CX), SI
MOVQ SI, (m_morebuf+gobuf_g)(BX)
// Set m->morepc to f's PC.
MOVQ 0(SP), AX
MOVQ AX, m_morepc(BX)
// Call newstack on m->g0's stack.
MOVQ m_g0(BX), BP
MOVQ BP, g(CX)
MOVQ (g_sched+gobuf_sp)(BP), SP
CALL runtime·newstack(SB)
MOVQ $0, 0x1003 // crash if newstack returns
RET
// Called from reflection library. Mimics morestack,
// reuses stack growth code to create a frame
// with the desired args running the desired function.
//
// func call(fn *byte, arg *byte, argsize uint32).
TEXT reflect·call(SB), 7, $0
get_tls(CX)
MOVQ m(CX), BX
// Save our caller's state as the PC and SP to
// restore when returning from f.
MOVQ 0(SP), AX // our caller's PC
MOVQ AX, (m_morebuf+gobuf_pc)(BX)
LEAQ 8(SP), AX // our caller's SP
MOVQ AX, (m_morebuf+gobuf_sp)(BX)
MOVQ g(CX), AX
MOVQ AX, (m_morebuf+gobuf_g)(BX)
// Set up morestack arguments to call f on a new stack.
// We set f's frame size to 1, as a hint to newstack
// that this is a call from reflect·call.
// If it turns out that f needs a larger frame than
// the default stack, f's usual stack growth prolog will
// allocate a new segment (and recopy the arguments).
MOVQ 8(SP), AX // fn
MOVQ 16(SP), DX // arg frame
MOVL 24(SP), CX // arg size
MOVQ AX, m_morepc(BX) // f's PC
MOVQ DX, m_moreargp(BX) // argument frame pointer
MOVL CX, m_moreargsize(BX) // f's argument size
MOVL $1, m_moreframesize(BX) // f's frame size
// Call newstack on m->g0's stack.
MOVQ m_g0(BX), BP
get_tls(CX)
MOVQ BP, g(CX)
MOVQ (g_sched+gobuf_sp)(BP), SP
CALL runtime·newstack(SB)
MOVQ $0, 0x1103 // crash if newstack returns
RET
// Return point when leaving stack.
TEXT runtime·lessstack(SB), 7, $0
// Save return value in m->cret
get_tls(CX)
MOVQ m(CX), BX
MOVQ AX, m_cret(BX)
// Call oldstack on m->g0's stack.
MOVQ m_g0(BX), BP
MOVQ BP, g(CX)
MOVQ (g_sched+gobuf_sp)(BP), SP
CALL runtime·oldstack(SB)
MOVQ $0, 0x1004 // crash if oldstack returns
RET
// morestack trampolines
TEXT runtime·morestack00(SB),7,$0
get_tls(CX)
MOVQ m(CX), BX
MOVQ $0, AX
MOVQ AX, m_moreframesize(BX)
MOVQ $runtime·morestack(SB), AX
JMP AX
TEXT runtime·morestack01(SB),7,$0
get_tls(CX)
MOVQ m(CX), BX
SHLQ $32, AX
MOVQ AX, m_moreframesize(BX)
MOVQ $runtime·morestack(SB), AX
JMP AX
TEXT runtime·morestack10(SB),7,$0
get_tls(CX)
MOVQ m(CX), BX
MOVLQZX AX, AX
MOVQ AX, m_moreframesize(BX)
MOVQ $runtime·morestack(SB), AX
JMP AX
TEXT runtime·morestack11(SB),7,$0
get_tls(CX)
MOVQ m(CX), BX
MOVQ AX, m_moreframesize(BX)
MOVQ $runtime·morestack(SB), AX
JMP AX
// subcases of morestack01
// with const of 8,16,...48
TEXT runtime·morestack8(SB),7,$0
PUSHQ $1
MOVQ $morestack<>(SB), AX
JMP AX
TEXT runtime·morestack16(SB),7,$0
PUSHQ $2
MOVQ $morestack<>(SB), AX
JMP AX
TEXT runtime·morestack24(SB),7,$0
PUSHQ $3
MOVQ $morestack<>(SB), AX
JMP AX
TEXT runtime·morestack32(SB),7,$0
PUSHQ $4
MOVQ $morestack<>(SB), AX
JMP AX
TEXT runtime·morestack40(SB),7,$0
PUSHQ $5
MOVQ $morestack<>(SB), AX
JMP AX
TEXT runtime·morestack48(SB),7,$0
PUSHQ $6
MOVQ $morestack<>(SB), AX
JMP AX
TEXT morestack<>(SB),7,$0
get_tls(CX)
MOVQ m(CX), BX
POPQ AX
SHLQ $35, AX
MOVQ AX, m_moreframesize(BX)
MOVQ $runtime·morestack(SB), AX
JMP AX
// bool cas(int32 *val, int32 old, int32 new)
// Atomically:
// if(*val == old){
// *val = new;
// return 1;
// } else
// return 0;
TEXT runtime·cas(SB), 7, $0
MOVQ 8(SP), BX
MOVL 16(SP), AX
MOVL 20(SP), CX
LOCK
CMPXCHGL CX, 0(BX)
JZ 3(PC)
MOVL $0, AX
RET
MOVL $1, AX
RET
// bool casp(void **val, void *old, void *new)
// Atomically:
// if(*val == old){
// *val = new;
// return 1;
// } else
// return 0;
TEXT runtime·casp(SB), 7, $0
MOVQ 8(SP), BX
MOVQ 16(SP), AX
MOVQ 24(SP), CX
LOCK
CMPXCHGQ CX, 0(BX)
JZ 3(PC)
MOVL $0, AX
RET
MOVL $1, AX
RET
// void jmpdefer(fn, sp);
// called from deferreturn.
// 1. pop the caller
// 2. sub 5 bytes from the callers return
// 3. jmp to the argument
TEXT runtime·jmpdefer(SB), 7, $0
MOVQ 8(SP), AX // fn
MOVQ 16(SP), BX // caller sp
LEAQ -8(BX), SP // caller sp after CALL
SUBQ $5, (SP) // return to CALL again
JMP AX // but first run the deferred function
// Dummy function to use in saved gobuf.PC,
// to match SP pointing at a return address.
// The gobuf.PC is unused by the contortions here
// but setting it to return will make the traceback code work.
TEXT return<>(SB),7,$0
RET
// asmcgocall(void(*fn)(void*), void *arg)
// Call fn(arg) on the scheduler stack,
// aligned appropriately for the gcc ABI.
// See cgocall.c for more details.
TEXT runtime·asmcgocall(SB),7,$0
MOVQ fn+0(FP), AX
MOVQ arg+8(FP), BX
MOVQ SP, DX
// Figure out if we need to switch to m->g0 stack.
// We get called to create new OS threads too, and those
// come in on the m->g0 stack already.
get_tls(CX)
MOVQ m(CX), BP
MOVQ m_g0(BP), SI
MOVQ g(CX), DI
CMPQ SI, DI
JEQ 6(PC)
MOVQ SP, (g_sched+gobuf_sp)(DI)
MOVQ $return<>(SB), (g_sched+gobuf_pc)(DI)
MOVQ DI, (g_sched+gobuf_g)(DI)
MOVQ SI, g(CX)
MOVQ (g_sched+gobuf_sp)(SI), SP
// Now on a scheduling stack (a pthread-created stack).
SUBQ $32, SP
ANDQ $~15, SP // alignment for gcc ABI
MOVQ DI, 16(SP) // save g
MOVQ DX, 8(SP) // save SP
MOVQ BX, DI // DI = first argument in AMD64 ABI
CALL AX
// Restore registers, g, stack pointer.
get_tls(CX)
MOVQ 16(SP), DI
MOVQ DI, g(CX)
MOVQ 8(SP), SP
RET
// cgocallback(void (*fn)(void*), void *frame, uintptr framesize)
// See cgocall.c for more details.
TEXT runtime·cgocallback(SB),7,$24
MOVQ fn+0(FP), AX
MOVQ frame+8(FP), BX
MOVQ framesize+16(FP), DX
// Save current m->g0->sched.sp on stack and then set it to SP.
get_tls(CX)
MOVQ m(CX), BP
MOVQ m_g0(BP), SI
PUSHQ (g_sched+gobuf_sp)(SI)
MOVQ SP, (g_sched+gobuf_sp)(SI)
// Switch to m->curg stack and call runtime.cgocallback
// with the three arguments. Because we are taking over
// the execution of m->curg but *not* resuming what had
// been running, we need to save that information (m->curg->gobuf)
// so that we can restore it when we're done.
// We can restore m->curg->gobuf.sp easily, because calling
// runtime.cgocallback leaves SP unchanged upon return.
// To save m->curg->gobuf.pc, we push it onto the stack.
// This has the added benefit that it looks to the traceback
// routine like cgocallback is going to return to that
// PC (because we defined cgocallback to have
// a frame size of 24, the same amount that we use below),
// so that the traceback will seamlessly trace back into
// the earlier calls.
MOVQ m_curg(BP), SI
MOVQ SI, g(CX)
MOVQ (g_sched+gobuf_sp)(SI), DI // prepare stack as DI
// Push gobuf.pc
MOVQ (g_sched+gobuf_pc)(SI), BP
SUBQ $8, DI
MOVQ BP, 0(DI)
// Push arguments to cgocallbackg.
// Frame size here must match the frame size above
// to trick traceback routines into doing the right thing.
SUBQ $24, DI
MOVQ AX, 0(DI)
MOVQ BX, 8(DI)
MOVQ DX, 16(DI)
// Switch stack and make the call.
MOVQ DI, SP
CALL runtime·cgocallbackg(SB)
// Restore g->gobuf (== m->curg->gobuf) from saved values.
get_tls(CX)
MOVQ g(CX), SI
MOVQ 24(SP), BP
MOVQ BP, (g_sched+gobuf_pc)(SI)
LEAQ (24+8)(SP), DI
MOVQ DI, (g_sched+gobuf_sp)(SI)
// Switch back to m->g0's stack and restore m->g0->sched.sp.
// (Unlike m->curg, the g0 goroutine never uses sched.pc,
// so we do not have to restore it.)
MOVQ m(CX), BP
MOVQ m_g0(BP), SI
MOVQ SI, g(CX)
MOVQ (g_sched+gobuf_sp)(SI), SP
POPQ (g_sched+gobuf_sp)(SI)
// Done!
RET
// check that SP is in range [g->stackbase, g->stackguard)
TEXT runtime·stackcheck(SB), 7, $0
get_tls(CX)
MOVQ g(CX), AX
CMPQ g_stackbase(AX), SP
JHI 2(PC)
INT $3
CMPQ SP, g_stackguard(AX)
JHI 2(PC)
INT $3
RET
TEXT runtime·memclr(SB),7,$0
MOVQ 8(SP), DI // arg 1 addr
MOVQ 16(SP), CX // arg 2 count
ADDQ $7, CX
SHRQ $3, CX
MOVQ $0, AX
CLD
REP
STOSQ
RET
TEXT runtime·getcallerpc(SB),7,$0
MOVQ x+0(FP),AX // addr of first arg
MOVQ -8(AX),AX // get calling pc
RET
TEXT runtime·setcallerpc(SB),7,$0
MOVQ x+0(FP),AX // addr of first arg
MOVQ x+8(FP), BX
MOVQ BX, -8(AX) // set calling pc
RET
TEXT runtime·getcallersp(SB),7,$0
MOVQ sp+0(FP), AX
RET
GLOBL runtime·tls0(SB), $64
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