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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 $~7, SP
MOVQ AX, 16(SP)
MOVQ BX, 24(SP)
// set the per-goroutine and per-mach registers
LEAQ m0(SB), m
LEAQ g0(SB), g
MOVQ g, m_g0(m) // m has pointer to its g0
// create istack out of the given (operating system) stack
LEAQ (-8192+104)(SP), AX
MOVQ AX, g_stackguard(g)
MOVQ SP, g_stackbase(g)
CLD // convention is D is always left cleared
CALL check(SB)
MOVL 16(SP), AX // copy argc
MOVL AX, 0(SP)
MOVQ 24(SP), AX // copy argv
MOVQ AX, 8(SP)
CALL args(SB)
CALL osinit(SB)
CALL schedinit(SB)
// create a new goroutine to start program
PUSHQ $mainstart(SB) // entry
PUSHQ $0 // arg size
CALL runtime·newproc(SB)
POPQ AX
POPQ AX
// start this M
CALL mstart(SB)
CALL notok(SB) // never returns
RET
TEXT mainstart(SB),7,$0
CALL main·init(SB)
CALL initdone(SB)
CALL main·main(SB)
PUSHQ $0
CALL exit(SB)
POPQ AX
CALL notok(SB)
RET
TEXT breakpoint(SB),7,$0
BYTE $0xcc
RET
/*
* go-routine
*/
// uintptr gosave(Gobuf*)
// save state in Gobuf; setjmp
TEXT 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)
MOVQ g, gobuf_g(AX)
MOVL $0, AX // return 0
RET
// void gogo(Gobuf*, uintptr)
// restore state from Gobuf; longjmp
TEXT gogo(SB), 7, $0
MOVQ 16(SP), AX // return 2nd arg
MOVQ 8(SP), BX // gobuf
MOVQ gobuf_g(BX), g
MOVQ 0(g), CX // make sure g != nil
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 gogocall(SB), 7, $0
MOVQ 16(SP), AX // fn
MOVQ 8(SP), BX // gobuf
MOVQ gobuf_g(BX), g
MOVQ 0(g), 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
/*
* support for morestack
*/
// Called during function prolog when more stack is needed.
TEXT runtime·morestack(SB),7,$0
// 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)(m)
LEAQ 16(SP), AX // f's caller's SP
MOVQ AX, (m_morebuf+gobuf_sp)(m)
MOVQ AX, (m_morefp)(m)
MOVQ g, (m_morebuf+gobuf_g)(m)
// Set m->morepc to f's PC.
MOVQ 0(SP), AX
MOVQ AX, m_morepc(m)
// Call newstack on m's scheduling stack.
MOVQ m_g0(m), g
MOVQ (m_sched+gobuf_sp)(m), SP
CALL 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
// 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)(m)
LEAQ 8(SP), AX // our caller's SP
MOVQ AX, (m_morebuf+gobuf_sp)(m)
MOVQ g, (m_morebuf+gobuf_g)(m)
// Set up morestack arguments to call f on a new stack.
// We set f's frame size to zero, meaning
// allocate a standard sized stack segment.
// If it turns out that f needs a larger frame than this,
// f's usual stack growth prolog will allocate
// a new segment (and recopy the arguments).
MOVQ 8(SP), AX // fn
MOVQ 16(SP), BX // arg frame
MOVL 24(SP), CX // arg size
MOVQ AX, m_morepc(m) // f's PC
MOVQ BX, m_morefp(m) // argument frame pointer
MOVL CX, m_moreargs(m) // f's argument size
MOVL $0, m_moreframe(m) // f's frame size
// Call newstack on m's scheduling stack.
MOVQ m_g0(m), g
MOVQ (m_sched+gobuf_sp)(m), SP
CALL 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
MOVQ AX, m_cret(m)
// Call oldstack on m's scheduling stack.
MOVQ m_g0(m), g
MOVQ (m_sched+gobuf_sp)(m), SP
CALL oldstack(SB)
MOVQ $0, 0x1004 // crash if oldstack returns
RET
// morestack trampolines
TEXT runtime·morestack00+0(SB),7,$0
MOVQ $0, AX
MOVQ AX, m_moreframe(m)
MOVQ $runtime·morestack+0(SB), AX
JMP AX
TEXT runtime·morestack01+0(SB),7,$0
SHLQ $32, AX
MOVQ AX, m_moreframe(m)
MOVQ $runtime·morestack+0(SB), AX
JMP AX
TEXT runtime·morestack10+0(SB),7,$0
MOVLQZX AX, AX
MOVQ AX, m_moreframe(m)
MOVQ $runtime·morestack+0(SB), AX
JMP AX
TEXT runtime·morestack11+0(SB),7,$0
MOVQ AX, m_moreframe(m)
MOVQ $runtime·morestack+0(SB), AX
JMP AX
// subcases of morestack01
// with const of 8,16,...48
TEXT runtime·morestack8(SB),7,$0
PUSHQ $1
MOVQ $runtime·morestackx(SB), AX
JMP AX
TEXT runtime·morestack16(SB),7,$0
PUSHQ $2
MOVQ $runtime·morestackx(SB), AX
JMP AX
TEXT runtime·morestack24(SB),7,$0
PUSHQ $3
MOVQ $runtime·morestackx(SB), AX
JMP AX
TEXT runtime·morestack32(SB),7,$0
PUSHQ $4
MOVQ $runtime·morestackx(SB), AX
JMP AX
TEXT runtime·morestack40(SB),7,$0
PUSHQ $5
MOVQ $runtime·morestackx(SB), AX
JMP AX
TEXT runtime·morestack48(SB),7,$0
PUSHQ $6
MOVQ $runtime·morestackx(SB), AX
JMP AX
TEXT runtime·morestackx(SB),7,$0
POPQ AX
SHLQ $35, AX
MOVQ AX, m_moreframe(m)
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 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
// 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 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
// runcgo(void(*fn)(void*), void *arg)
// Call fn(arg) on the scheduler stack,
// aligned appropriately for the gcc ABI.
// Save g and m across the call,
// since the foreign code might reuse them.
TEXT runcgo(SB),7,$32
// Save old registers.
MOVQ fn+0(FP),AX
MOVQ arg+8(FP),DI // DI = first argument in AMD64 ABI
MOVQ SP, CX
// Figure out if we need to switch to m->g0 stack.
MOVQ m_g0(m), R8
CMPQ R8, g
JEQ 2(PC)
MOVQ (m_sched+gobuf_sp)(m), SP
// Now on a scheduling stack (a pthread-created stack).
SUBQ $32, SP
ANDQ $~15, SP // alignment for gcc ABI
MOVQ g, 24(SP) // save old g, m, SP
MOVQ m, 16(SP)
MOVQ CX, 8(SP)
CALL AX
// Restore registers, stack pointer.
MOVQ 16(SP), m
MOVQ 24(SP), g
MOVQ 8(SP), SP
RET
// check that SP is in range [g->stackbase, g->stackguard)
TEXT stackcheck(SB), 7, $0
CMPQ g_stackbase(g), SP
JHI 2(PC)
INT $3
CMPQ SP, g_stackguard(g)
JHI 2(PC)
INT $3
RET
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