runtime: added go files for mips64 architecture support
Change-Id: Ia496470e48b3c5d39fb9fef99fac356dfb73a949
Reviewed-on: https://go-review.googlesource.com/14927
Reviewed-by: Minux Ma <minux@golang.org>
diff --git a/src/runtime/sys_mips64x.go b/src/runtime/sys_mips64x.go
new file mode 100644
index 0000000..9e7d805
--- /dev/null
+++ b/src/runtime/sys_mips64x.go
@@ -0,0 +1,43 @@
+// Copyright 2015 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.
+
+// +build mips64 mips64le
+
+package runtime
+
+import "unsafe"
+
+// adjust Gobuf as if it executed a call to fn with context ctxt
+// and then did an immediate Gosave.
+func gostartcall(buf *gobuf, fn, ctxt unsafe.Pointer) {
+ if buf.lr != 0 {
+ throw("invalid use of gostartcall")
+ }
+ buf.lr = buf.pc
+ buf.pc = uintptr(fn)
+ buf.ctxt = ctxt
+}
+
+// Called to rewind context saved during morestack back to beginning of function.
+// To help us, the linker emits a jmp back to the beginning right after the
+// call to morestack. We just have to decode and apply that jump.
+func rewindmorestack(buf *gobuf) {
+ var inst uint32
+ if buf.pc&3 == 0 && buf.pc != 0 {
+ inst = *(*uint32)(unsafe.Pointer(buf.pc))
+ if inst>>26 == 2 { // JMP addr
+ //print("runtime: rewind pc=", hex(buf.pc), " to pc=", hex(buf.pc &^ uintptr(1<<28-1) | uintptr((inst&^0xfc000000)<<2)), "\n");
+ buf.pc &^= 1<<28 - 1
+ buf.pc |= uintptr((inst &^ 0xfc000000) << 2)
+ return
+ }
+ if inst>>16 == 0x1000 { // BEQ R0, R0, offset
+ //print("runtime: rewind pc=", hex(buf.pc), " to pc=", hex(buf.pc + uintptr(int32(int16(inst&0xffff))<<2 + 4)), "\n");
+ buf.pc += uintptr(int32(int16(inst&0xffff))<<2 + 4)
+ return
+ }
+ }
+ print("runtime: pc=", hex(buf.pc), " ", hex(inst), "\n")
+ throw("runtime: misuse of rewindmorestack")
+}
