Adding upstream version 1.21.8.upstream/1.21.8

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 51 insertions, 0 deletions

diff --git a/src/runtime/tls_ppc64x.s b/src/runtime/tls_ppc64x.s
new file mode 100644
index 0000000..17aec9f
--- /dev/null
+++ b/src/runtime/tls_ppc64x.s
@@ -0,0 +1,51 @@
+// Copyright 2014 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.
+
+//go:build ppc64 || ppc64le
+
+#include "go_asm.h"
+#include "go_tls.h"
+#include "funcdata.h"
+#include "textflag.h"
+
+// We have to resort to TLS variable to save g (R30).
+// 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 R30,
+// 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
+// ppc64 code that will overwrite this register.
+//
+// If !iscgo, this is a no-op.
+//
+// NOTE: setg_gcc<> assume this clobbers only R31.
+TEXT runtime·save_g(SB),NOSPLIT|NOFRAME,$0-0
+#ifndef GOOS_aix
+	MOVBZ	runtime·iscgo(SB), R31
+	CMP	R31, $0
+	BEQ	nocgo
+#endif
+	MOVD	runtime·tls_g(SB), R31
+	MOVD	g, 0(R31)
+
+nocgo:
+	RET
+
+// load_g loads the g register from pthread-provided
+// thread-local memory, for use after calling externally compiled
+// ppc64 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 (R30), and R31.
+TEXT runtime·load_g(SB),NOSPLIT|NOFRAME,$0-0
+	MOVD	runtime·tls_g(SB), R31
+	MOVD	0(R31), g
+	RET
+
+GLOBL runtime·tls_g+0(SB), TLSBSS+DUPOK, $8