1 files changed, 83 insertions, 0 deletions
diff --git a/src/runtime/signal_amd64.go b/src/runtime/signal_amd64.go
new file mode 100644
index 0000000..6ab1f75
--- /dev/null
+++ b/src/runtime/signal_amd64.go
@@ -0,0 +1,83 @@
+// Copyright 2013 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 amd64
+// +build darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package runtime
+
+import (
+	"runtime/internal/sys"
+	"unsafe"
+)
+
+func dumpregs(c *sigctxt) {
+	print("rax    ", hex(c.rax()), "\n")
+	print("rbx    ", hex(c.rbx()), "\n")
+	print("rcx    ", hex(c.rcx()), "\n")
+	print("rdx    ", hex(c.rdx()), "\n")
+	print("rdi    ", hex(c.rdi()), "\n")
+	print("rsi    ", hex(c.rsi()), "\n")
+	print("rbp    ", hex(c.rbp()), "\n")
+	print("rsp    ", hex(c.rsp()), "\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("rip    ", hex(c.rip()), "\n")
+	print("rflags ", hex(c.rflags()), "\n")
+	print("cs     ", hex(c.cs()), "\n")
+	print("fs     ", hex(c.fs()), "\n")
+	print("gs     ", hex(c.gs()), "\n")
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func (c *sigctxt) sigpc() uintptr { return uintptr(c.rip()) }
+
+func (c *sigctxt) sigsp() uintptr { return uintptr(c.rsp()) }
+func (c *sigctxt) siglr() uintptr { return 0 }
+func (c *sigctxt) fault() uintptr { return uintptr(c.sigaddr()) }
+
+// preparePanic sets up the stack to look like a call to sigpanic.
+func (c *sigctxt) preparePanic(sig uint32, gp *g) {
+	// Work around Leopard bug that doesn't set FPE_INTDIV.
+	// Look at instruction to see if it is a divide.
+	// Not necessary in Snow Leopard (si_code will be != 0).
+	if GOOS == "darwin" && sig == _SIGFPE && gp.sigcode0 == 0 {
+		pc := (*[4]byte)(unsafe.Pointer(gp.sigpc))
+		i := 0
+		if pc[i]&0xF0 == 0x40 { // 64-bit REX prefix
+			i++
+		} else if pc[i] == 0x66 { // 16-bit instruction prefix
+			i++
+		}
+		if pc[i] == 0xF6 || pc[i] == 0xF7 {
+			gp.sigcode0 = _FPE_INTDIV
+		}
+	}
+
+	pc := uintptr(c.rip())
+	sp := uintptr(c.rsp())
+
+	if shouldPushSigpanic(gp, pc, *(*uintptr)(unsafe.Pointer(sp))) {
+		c.pushCall(funcPC(sigpanic), pc)
+	} else {
+		// Not safe to push the call. Just clobber the frame.
+		c.set_rip(uint64(funcPC(sigpanic)))
+	}
+}
+
+func (c *sigctxt) pushCall(targetPC, resumePC uintptr) {
+	// Make it look like we called target at resumePC.
+	sp := uintptr(c.rsp())
+	sp -= sys.PtrSize
+	*(*uintptr)(unsafe.Pointer(sp)) = resumePC
+	c.set_rsp(uint64(sp))
+	c.set_rip(uint64(targetPC))
+}