runtime: add support for linux/arm64

Change-Id: Ibda6a5bedaff57fd161d63fc04ad260931d34413
Reviewed-on: https://go-review.googlesource.com/7142
Reviewed-by: Russ Cox <rsc@golang.org>

1 files changed, 139 insertions, 0 deletions

diff --git a/src/runtime/signal_arm64.go b/src/runtime/signal_arm64.go
new file mode 100644
index 0000000000..cc8985872c
--- /dev/null
+++ b/src/runtime/signal_arm64.go
@@ -0,0 +1,139 @@
+// 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.
+
+// +build linux
+
+package runtime
+
+import "unsafe"
+
+func dumpregs(c *sigctxt) {
+	print("r0      ", hex(c.r0()), "\n")
+	print("r1      ", hex(c.r1()), "\n")
+	print("r2      ", hex(c.r2()), "\n")
+	print("r3      ", hex(c.r3()), "\n")
+	print("r4      ", hex(c.r4()), "\n")
+	print("r5      ", hex(c.r5()), "\n")
+	print("r6      ", hex(c.r6()), "\n")
+	print("r7      ", hex(c.r7()), "\n")
+	print("r8      ", hex(c.r8()), "\n")
+	print("r9      ", hex(c.r9()), "\n")
+	print("r10     ", hex(c.r10()), "\n")
+	print("r11     ", hex(c.r11()), "\n")
+	print("r12     ", hex(c.r12()), "\n")
+	print("r13     ", hex(c.r13()), "\n")
+	print("r14     ", hex(c.r14()), "\n")
+	print("r15     ", hex(c.r15()), "\n")
+	print("r16     ", hex(c.r16()), "\n")
+	print("r17     ", hex(c.r17()), "\n")
+	print("r18     ", hex(c.r18()), "\n")
+	print("r19     ", hex(c.r19()), "\n")
+	print("r20     ", hex(c.r20()), "\n")
+	print("r21     ", hex(c.r21()), "\n")
+	print("r22     ", hex(c.r22()), "\n")
+	print("r23     ", hex(c.r23()), "\n")
+	print("r24     ", hex(c.r24()), "\n")
+	print("r25     ", hex(c.r25()), "\n")
+	print("r26     ", hex(c.r26()), "\n")
+	print("r27     ", hex(c.r27()), "\n")
+	print("r28     ", hex(c.r28()), "\n")
+	print("r29     ", hex(c.r29()), "\n")
+	print("lr      ", hex(c.lr()), "\n")
+	print("sp      ", hex(c.sp()), "\n")
+	print("pc      ", hex(c.pc()), "\n")
+	print("fault   ", hex(c.fault()), "\n")
+}
+
+func sighandler(sig uint32, info *siginfo, ctxt unsafe.Pointer, gp *g) {
+	_g_ := getg()
+	c := &sigctxt{info, ctxt}
+
+	if sig == _SIGPROF {
+		sigprof(uintptr(c.pc()), uintptr(c.sp()), uintptr(c.lr()), gp, _g_.m)
+		return
+	}
+
+	flags := int32(_SigThrow)
+	if sig < uint32(len(sigtable)) {
+		flags = sigtable[sig].flags
+	}
+	if c.sigcode() != _SI_USER && flags&_SigPanic != 0 {
+		// Make it look like a call to the signal func.
+		// Have to pass arguments out of band since
+		// augmenting the stack frame would break
+		// the unwinding code.
+		gp.sig = sig
+		gp.sigcode0 = uintptr(c.sigcode())
+		gp.sigcode1 = uintptr(c.fault())
+		gp.sigpc = uintptr(c.pc())
+
+		// We arrange lr, and pc to pretend the panicking
+		// function calls sigpanic directly.
+		// Always save LR to stack so that panics in leaf
+		// functions are correctly handled. This smashes
+		// the stack frame but we're not going back there
+		// anyway.
+		sp := c.sp() - spAlign // needs only sizeof uint64, but must align the stack
+		c.set_sp(sp)
+		*(*uint64)(unsafe.Pointer(uintptr(sp))) = c.lr()
+
+		// Don't bother saving PC if it's zero, which is
+		// probably a call to a nil func: the old link register
+		// is more useful in the stack trace.
+		if gp.sigpc != 0 {
+			c.set_lr(uint64(gp.sigpc))
+		}
+
+		// In case we are panicking from external C code
+		c.set_r28(uint64(uintptr(unsafe.Pointer(gp))))
+		c.set_pc(uint64(funcPC(sigpanic)))
+		return
+	}
+
+	if c.sigcode() == _SI_USER || flags&_SigNotify != 0 {
+		if sigsend(sig) {
+			return
+		}
+	}
+
+	if flags&_SigKill != 0 {
+		exit(2)
+	}
+
+	if flags&_SigThrow == 0 {
+		return
+	}
+
+	_g_.m.throwing = 1
+	_g_.m.caughtsig = gp
+	startpanic()
+
+	if sig < uint32(len(sigtable)) {
+		print(sigtable[sig].name, "\n")
+	} else {
+		print("Signal ", sig, "\n")
+	}
+
+	print("PC=", hex(c.pc()), "\n")
+	if _g_.m.lockedg != nil && _g_.m.ncgo > 0 && gp == _g_.m.g0 {
+		print("signal arrived during cgo execution\n")
+		gp = _g_.m.lockedg
+	}
+	print("\n")
+
+	var docrash bool
+	if gotraceback(&docrash) > 0 {
+		goroutineheader(gp)
+		tracebacktrap(uintptr(c.pc()), uintptr(c.sp()), uintptr(c.lr()), gp)
+		tracebackothers(gp)
+		print("\n")
+		dumpregs(c)
+	}
+
+	if docrash {
+		crash()
+	}
+
+	exit(2)
+}