github.com/xushiwei/go@v0.0.0-20130601165731-2b9d83f45bc9/src/pkg/runtime/cgo/asm_arm.s (about)

     1  // Copyright 2012 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   * void crosscall2(void (*fn)(void*, int32), void*, int32)
     7   * Save registers and call fn with two arguments.
     8   */
     9  TEXT crosscall2(SB),7,$-4
    10  	/* 
    11  	 * We still need to save all callee save register as before, and then
    12  	 *  push 2 args for fn (R1 and R2).
    13  	 * Also note that at procedure entry in 5c/5g world, 4(R13) will be the
    14  	 *  first arg, so we must push another dummy reg (R0) for 0(R13).
    15  	 *  Additionally, cgo_tls_set_gm will clobber R0, so we need to save R0
    16  	 *  nevertheless.
    17  	 */
    18  	MOVM.WP	[R0, R1, R2, R4, R5, R6, R7, R8, R9, R10, R11, R12, R14], (R13)
    19  	MOVW	_cgo_load_gm(SB), R0
    20  	BL	(R0)
    21  	MOVW	PC, R14
    22  	MOVW	0(R13), PC
    23  	MOVM.IAW	(R13), [R0, R1, R2, R4, R5, R6, R7, R8, R9, R10, R11, R12, PC]