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.file "gcc_amd64.S" 6 7/* 8 * Apple still insists on underscore prefixes for C function names. 9 */ 10#if defined(__APPLE__) 11#define EXT(s) _##s 12#else 13#define EXT(s) s 14#endif 15 16/* 17 * void crosscall1(void (*fn)(void), void (*setg_gcc)(void*), void *g) 18 * 19 * Calling into the gc tool chain, where all registers are caller save. 20 * Called from standard x86-64 ABI, where %rbx, %rbp, %r12-%r15 21 * are callee-save so they must be saved explicitly. 22 * The standard x86-64 ABI passes the three arguments m, g, fn 23 * in %rdi, %rsi, %rdx. 24 */ 25.globl EXT(crosscall1) 26EXT(crosscall1): 27 pushq %rbx 28 pushq %rbp 29 pushq %r12 30 pushq %r13 31 pushq %r14 32 pushq %r15 33 34#if defined(_WIN64) 35 movq %r8, %rdi /* arg of setg_gcc */ 36 call *%rdx /* setg_gcc */ 37 call *%rcx /* fn */ 38#else 39 movq %rdi, %rbx 40 movq %rdx, %rdi /* arg of setg_gcc */ 41 call *%rsi /* setg_gcc */ 42 call *%rbx /* fn */ 43#endif 44 45 popq %r15 46 popq %r14 47 popq %r13 48 popq %r12 49 popq %rbp 50 popq %rbx 51 ret 52 53#ifdef __ELF__ 54.section .note.GNU-stack,"",@progbits 55#endif 56