blob: 614de4b43b867f49230c3778756da5f0af2b4390 [file] [log] [blame]
// Copyright 2016 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.
/*
* void crosscall_s390x(void (*fn)(void), void *g)
*
* Calling into the go tool chain, where all registers are caller save.
* Called from standard s390x C ABI, where r6-r13, r15, and f8-f15 are
* callee-save, so they must be saved explicitly.
*/
.globl crosscall_s390x
crosscall_s390x:
/* save r6-r15 in the register save area of the calling function */
stmg %r6, %r15, 48(%r15)
/* allocate 64 bytes of stack space to save f8-f15 */
lay %r15, -64(%r15)
/* save callee-saved floating point registers */
std %f8, 0(%r15)
std %f9, 8(%r15)
std %f10, 16(%r15)
std %f11, 24(%r15)
std %f12, 32(%r15)
std %f13, 40(%r15)
std %f14, 48(%r15)
std %f15, 56(%r15)
/* restore g pointer */
lgr %r13, %r3
/* call fn */
basr %r14, %r2
/* restore floating point registers */
ld %f8, 0(%r15)
ld %f9, 8(%r15)
ld %f10, 16(%r15)
ld %f11, 24(%r15)
ld %f12, 32(%r15)
ld %f13, 40(%r15)
ld %f14, 48(%r15)
ld %f15, 56(%r15)
/* de-allocate stack frame */
la %r15, 64(%r15)
/* restore general purpose registers */
lmg %r6, %r15, 48(%r15)
br %r14 /* restored by lmg */
#ifdef __ELF__
.section .note.GNU-stack,"",%progbits
#endif