From f68878f0fc542708bbe1dc4f131d32b21fac0d3c Mon Sep 17 00:00:00 2001 From: Joel Sing Date: Tue, 8 Dec 2020 04:30:22 +1100 Subject: [PATCH] cmd/dist,runtime: support cgo on openbsd/mips64 Add support for cgo on openbsd/mips64. Fixes #43005 Change-Id: I2386204f53fa984a01a9d89f0b6c96455768f326 Reviewed-on: https://go-review.googlesource.com/c/go/+/275896 Trust: Joel Sing Run-TryBot: Joel Sing Reviewed-by: Cherry Zhang --- src/cmd/dist/build.go | 2 +- src/cmd/link/internal/mips64/asm.go | 15 ++++++- src/cmd/nm/nm_cgo_test.go | 2 +- src/runtime/cgo/gcc_openbsd_mips64.c | 67 ++++++++++++++++++++++++++++ 4 files changed, 83 insertions(+), 3 deletions(-) create mode 100644 src/runtime/cgo/gcc_openbsd_mips64.c diff --git a/src/cmd/dist/build.go b/src/cmd/dist/build.go index c81fe6a586..00e23ef179 100644 --- a/src/cmd/dist/build.go +++ b/src/cmd/dist/build.go @@ -1590,7 +1590,7 @@ var cgoEnabled = map[string]bool{ "openbsd/amd64": true, "openbsd/arm": true, "openbsd/arm64": true, - "openbsd/mips64": false, + "openbsd/mips64": true, "plan9/386": false, "plan9/amd64": false, "plan9/arm": false, diff --git a/src/cmd/link/internal/mips64/asm.go b/src/cmd/link/internal/mips64/asm.go index 55b4ba2fc8..f7f91d1e8b 100644 --- a/src/cmd/link/internal/mips64/asm.go +++ b/src/cmd/link/internal/mips64/asm.go @@ -52,6 +52,8 @@ func elfreloc1(ctxt *ld.Link, out *ld.OutBuf, ldr *loader.Loader, s loader.Sym, // type uint8 // addend int64 + addend := r.Xadd + out.Write64(uint64(sectoff)) elfsym := ld.ElfSymForReloc(ctxt, r.Xsym) @@ -77,11 +79,17 @@ func elfreloc1(ctxt *ld.Link, out *ld.OutBuf, ldr *loader.Loader, s loader.Sym, out.Write8(uint8(elf.R_MIPS_HI16)) case objabi.R_ADDRMIPSTLS: out.Write8(uint8(elf.R_MIPS_TLS_TPREL_LO16)) + if ctxt.Target.IsOpenbsd() { + // OpenBSD mips64 does not currently offset TLS by 0x7000, + // as such we need to add this back to get the correct offset + // via the external linker. + addend += 0x7000 + } case objabi.R_CALLMIPS, objabi.R_JMPMIPS: out.Write8(uint8(elf.R_MIPS_26)) } - out.Write64(uint64(r.Xadd)) + out.Write64(uint64(addend)) return true } @@ -124,6 +132,11 @@ func archreloc(target *ld.Target, ldr *loader.Loader, syms *ld.ArchSyms, r loade case objabi.R_ADDRMIPSTLS: // thread pointer is at 0x7000 offset from the start of TLS data area t := ldr.SymValue(rs) + r.Add() - 0x7000 + if target.IsOpenbsd() { + // OpenBSD mips64 does not currently offset TLS by 0x7000, + // as such we need to add this back to get the correct offset. + t += 0x7000 + } if t < -32768 || t >= 32678 { ldr.Errorf(s, "TLS offset out of range %d", t) } diff --git a/src/cmd/nm/nm_cgo_test.go b/src/cmd/nm/nm_cgo_test.go index d0937904a2..1544be041a 100644 --- a/src/cmd/nm/nm_cgo_test.go +++ b/src/cmd/nm/nm_cgo_test.go @@ -30,7 +30,7 @@ func canInternalLink() bool { } case "openbsd": switch runtime.GOARCH { - case "arm64": + case "arm64", "mips64": return false } case "windows": diff --git a/src/runtime/cgo/gcc_openbsd_mips64.c b/src/runtime/cgo/gcc_openbsd_mips64.c new file mode 100644 index 0000000000..79f039a373 --- /dev/null +++ b/src/runtime/cgo/gcc_openbsd_mips64.c @@ -0,0 +1,67 @@ +// Copyright 2020 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 +#include +#include +#include +#include "libcgo.h" +#include "libcgo_unix.h" + +static void* threadentry(void*); +static void (*setg_gcc)(void*); + +void +x_cgo_init(G *g, void (*setg)(void*)) +{ + pthread_attr_t attr; + size_t size; + + setg_gcc = setg; + pthread_attr_init(&attr); + pthread_attr_getstacksize(&attr, &size); + g->stacklo = (uintptr)&attr - size + 4096; + pthread_attr_destroy(&attr); +} + +void +_cgo_sys_thread_start(ThreadStart *ts) +{ + pthread_attr_t attr; + sigset_t ign, oset; + pthread_t p; + size_t size; + int err; + + sigfillset(&ign); + pthread_sigmask(SIG_SETMASK, &ign, &oset); + + pthread_attr_init(&attr); + pthread_attr_getstacksize(&attr, &size); + + // Leave stacklo=0 and set stackhi=size; mstart will do the rest. + ts->g->stackhi = size; + err = _cgo_try_pthread_create(&p, &attr, threadentry, ts); + + pthread_sigmask(SIG_SETMASK, &oset, nil); + + if (err != 0) { + fprintf(stderr, "runtime/cgo: pthread_create failed: %s\n", strerror(err)); + abort(); + } +} + +extern void crosscall1(void (*fn)(void), void (*setg_gcc)(void*), void *g); + +static void* +threadentry(void *v) +{ + ThreadStart ts; + + ts = *(ThreadStart*)v; + free(v); + + crosscall1(ts.fn, setg_gcc, (void*)ts.g); + return nil; +}