runtime: use uintXX instead of *byte for si_addr on Darwin

Currently, Darwin's siginfo type uses *byte for the si_addr
field. This results in unwanted write barriers in set_sigaddr. It's
also pointless since it never points to anything real and the get/set
methods return/take uintXX and cast it from/to the pointer.

All other arches use a uint type for this field. Change Darwin to
match. This simplifies the get/set methods and eliminates the unwanted
write barriers.

Change-Id: Ifdb5646d35e1f2f6808b87a3d59745ec9718add1
Reviewed-on: https://go-review.googlesource.com/8086
Reviewed-by: Austin Clements <austin@google.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/runtime/signal_darwin_amd64.go b/src/runtime/signal_darwin_amd64.go
index 409bc6d575..dbf044814c 100644
--- a/src/runtime/signal_darwin_amd64.go
+++ b/src/runtime/signal_darwin_amd64.go
@@ -34,9 +34,9 @@ func (c *sigctxt) cs() uint64      { return c.regs().cs }
 func (c *sigctxt) fs() uint64      { return c.regs().fs }
 func (c *sigctxt) gs() uint64      { return c.regs().gs }
 func (c *sigctxt) sigcode() uint64 { return uint64(c.info.si_code) }
-func (c *sigctxt) sigaddr() uint64 { return uint64(uintptr(unsafe.Pointer(c.info.si_addr))) }
+func (c *sigctxt) sigaddr() uint64 { return c.info.si_addr }
 
 func (c *sigctxt) set_rip(x uint64)     { c.regs().rip = x }
 func (c *sigctxt) set_rsp(x uint64)     { c.regs().rsp = x }
 func (c *sigctxt) set_sigcode(x uint64) { c.info.si_code = int32(x) }
-func (c *sigctxt) set_sigaddr(x uint64) { c.info.si_addr = (*byte)(unsafe.Pointer(uintptr(x))) }
+func (c *sigctxt) set_sigaddr(x uint64) { c.info.si_addr = x }