diff options
Diffstat (limited to '')
| -rw-r--r-- | src/runtime/cgo/gcc_s390x.S | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/src/runtime/cgo/gcc_s390x.S b/src/runtime/cgo/gcc_s390x.S new file mode 100644 index 0000000..614de4b --- /dev/null +++ b/src/runtime/cgo/gcc_s390x.S @@ -0,0 +1,56 @@ +// 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 |