mirror of
https://github.com/golang/go
synced 2024-11-19 16:04:48 -07:00
52 lines
1.5 KiB
ArmAsm
52 lines
1.5 KiB
ArmAsm
|
// 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 "go_asm.h"
|
||
|
|
#include "go_tls.h"
|
||
|
|
#include "funcdata.h"
|
||
|
|
#include "textflag.h"
|
||
|
|
|
||
|
|
// We have to resort to TLS variable to save g (R13).
|
||
|
|
// One reason is that external code might trigger
|
||
|
|
// SIGSEGV, and our runtime.sigtramp don't even know we
|
||
|
|
// are in external code, and will continue to use R13,
|
||
|
|
// this might well result in another SIGSEGV.
|
||
|
|
|
||
|
|
// save_g saves the g register into pthread-provided
|
||
|
|
// thread-local memory, so that we can call externally compiled
|
||
|
|
// s390x code that will overwrite this register.
|
||
|
|
//
|
||
|
|
// If !iscgo, this is a no-op.
|
||
|
|
//
|
||
|
|
// NOTE: setg_gcc<> assume this clobbers only R10 and R11.
|
||
|
|
TEXT runtime·save_g(SB),NOSPLIT|NOFRAME,$0-0
|
||
|
|
MOVB runtime·iscgo(SB), R10
|
||
|
|
CMPBEQ R10, $0, nocgo
|
||
|
|
MOVW AR0, R11
|
||
|
|
SLD $32, R11
|
||
|
|
MOVW AR1, R11
|
||
|
|
MOVD runtime·tls_g(SB), R10
|
||
|
|
MOVD g, 0(R10)(R11*1)
|
||
|
|
nocgo:
|
||
|
|
RET
|
||
|
|
|
||
|
|
// load_g loads the g register from pthread-provided
|
||
|
|
// thread-local memory, for use after calling externally compiled
|
||
|
|
// s390x code that overwrote those registers.
|
||
|
|
//
|
||
|
|
// This is never called directly from C code (it doesn't have to
|
||
|
|
// follow the C ABI), but it may be called from a C context, where the
|
||
|
|
// usual Go registers aren't set up.
|
||
|
|
//
|
||
|
|
// NOTE: _cgo_topofstack assumes this only clobbers g (R13), R10 and R11.
|
||
|
|
TEXT runtime·load_g(SB),NOSPLIT|NOFRAME,$0-0
|
||
|
|
MOVW AR0, R11
|
||
|
|
SLD $32, R11
|
||
|
|
MOVW AR1, R11
|
||
|
|
MOVD runtime·tls_g(SB), R10
|
||
|
|
MOVD 0(R10)(R11*1), g
|
||
|
|
RET
|
||
|
|
|
||
|
|
GLOBL runtime·tls_g+0(SB),TLSBSS,$8
|