root/src/pkg/runtime/cgo/gcc_windows_amd64.c

DEFINITIONS

1. x_cgo_init
2. _cgo_sys_thread_start
3. threadentry

// 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.

#define WIN64_LEAN_AND_MEAN
#include <windows.h>
#include <process.h>
#include <stdlib.h>
#include <stdio.h>
#include "libcgo.h"

static void threadentry(void*);

/* 2MB is default stack size for 64-bit Windows.
   Allocation granularity on Windows is typically 64 KB.
   The constant is also hardcoded in cmd/ld/pe.c (keep synchronized). */
#define STACKSIZE (2*1024*1024)

void
x_cgo_init(G *g)
{
        int tmp;
        g->stackguard = (uintptr)&tmp - STACKSIZE + 8*1024;
}


void
_cgo_sys_thread_start(ThreadStart *ts)
{
        uintptr_t thandle;

        thandle = _beginthread(threadentry, 0, ts);
        if(thandle == -1) {
                fprintf(stderr, "runtime: failed to create new OS thread (%d)\n", errno);
                abort();
        }
}

static void
threadentry(void *v)
{
        ThreadStart ts;

        ts = *(ThreadStart*)v;
        free(v);

        ts.g->stackbase = (uintptr)&ts;
        ts.g->stackguard = (uintptr)&ts - STACKSIZE + 8*1024;

        /*
         * Set specific keys in thread local storage.
         */
        asm volatile (
          "movq %0, %%gs:0x28\n"        // MOVL tls0, 0x28(GS)
          "movq %%gs:0x28, %%rax\n" // MOVQ 0x28(GS), tmp
          "movq %1, 0(%%rax)\n" // MOVQ g, 0(GS)
          "movq %2, 8(%%rax)\n" // MOVQ m, 8(GS)
          :: "r"(ts.tls), "r"(ts.g), "r"(ts.m) : "%rax"
        );

        crosscall_amd64(ts.fn);
}