[GHC] #12948: Implement unwind rules for non-Intel architectures

[GHC]

#12948: Implement unwind rules for non-Intel architectures
-------------------------------------+-------------------------------------
           Reporter:  bgamari        |             Owner:
               Type:  task           |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.0.1
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 To support DWARF-based stack unwinding, a platform needs a few things,

  * Valid unwind records in `stg_stop_thread` (defined in
 `rts/StgStartup.cmm`)
  * Support in the native code generator (by implementing the
 `generateUnwindTable` field of `NcgImpl`)
  * A mapping of register numbers to DWARF register numbers (see
 `dwarfRegNo` in `nativeGhc/Dwarf/Constants.hs`)
  * For unwinding support in the runtime system:
     * Unwinding support in `libdw`
     * a `set_initial_registers` implementation (see `rts/Libdw.c`)

 Currently the only platforms that has all of these implemented is x86_64
 and i386.  Someone should pick up the other platforms.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12948>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler