diff options
Diffstat (limited to '')
| -rw-r--r-- | src/runtime/cgo/asm_s390x.s | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/src/runtime/cgo/asm_s390x.s b/src/runtime/cgo/asm_s390x.s new file mode 100644 index 0000000..8f74fd5 --- /dev/null +++ b/src/runtime/cgo/asm_s390x.s @@ -0,0 +1,68 @@ +// 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. + +#include "textflag.h" + +// Set the x_crosscall2_ptr C function pointer variable point to crosscall2. +// It's such a pointer chain: _crosscall2_ptr -> x_crosscall2_ptr -> crosscall2 +// Use a local trampoline, to avoid taking the address of a dynamically exported +// function. +TEXT ·set_crosscall2(SB),NOSPLIT,$0-0 + MOVD _crosscall2_ptr(SB), R1 + MOVD $crosscall2_trampoline<>(SB), R2 + MOVD R2, (R1) + RET + +TEXT crosscall2_trampoline<>(SB),NOSPLIT,$0-0 + JMP crosscall2(SB) + +// Called by C code generated by cmd/cgo. +// func crosscall2(fn, a unsafe.Pointer, n int32, ctxt uintptr) +// Saves C callee-saved registers and calls cgocallback with three arguments. +// fn is the PC of a func(a unsafe.Pointer) function. +TEXT crosscall2(SB),NOSPLIT|NOFRAME,$0 + // Start with standard C stack frame layout and linkage. + + // Save R6-R15 in the register save area of the calling function. + STMG R6, R15, 48(R15) + + // Allocate 96 bytes on the stack. + MOVD $-96(R15), R15 + + // Save F8-F15 in our stack frame. + FMOVD F8, 32(R15) + FMOVD F9, 40(R15) + FMOVD F10, 48(R15) + FMOVD F11, 56(R15) + FMOVD F12, 64(R15) + FMOVD F13, 72(R15) + FMOVD F14, 80(R15) + FMOVD F15, 88(R15) + + // Initialize Go ABI environment. + BL runtime·load_g(SB) + + MOVD R2, 8(R15) // fn unsafe.Pointer + MOVD R3, 16(R15) // a unsafe.Pointer + // Skip R4 = n uint32 + MOVD R5, 24(R15) // ctxt uintptr + BL runtime·cgocallback(SB) + + FMOVD 32(R15), F8 + FMOVD 40(R15), F9 + FMOVD 48(R15), F10 + FMOVD 56(R15), F11 + FMOVD 64(R15), F12 + FMOVD 72(R15), F13 + FMOVD 80(R15), F14 + FMOVD 88(R15), F15 + + // De-allocate stack frame. + MOVD $96(R15), R15 + + // Restore R6-R15. + LMG 48(R15), R6, R15 + + RET + |