• Peter Trommler's avatar
    Implement PowerPC 64-bit native code backend for Linux · d3c1dda6
    Peter Trommler authored
    Extend the PowerPC 32-bit native code generator for "64-bit
    PowerPC ELF Application Binary Interface Supplement 1.9" by
    Ian Lance Taylor and "Power Architecture 64-Bit ELF V2 ABI Specification --
    OpenPOWER ABI for Linux Supplement" by IBM.
    The latter ABI is mainly used on POWER7/7+ and POWER8
    Linux systems running in little-endian mode. The code generator
    supports both static and dynamic linking. PowerPC 64-bit
    code for ELF ABI 1.9 and 2 is mostly position independent
    anyway, and thus so is all the code emitted by the code
    generator. In other words, -fPIC does not make a difference.
    
    rts/stg/SMP.h support is implemented.
    
    Following the spirit of the introductory comment in
    PPC/CodeGen.hs, the rest of the code is a straightforward
    extension of the 32-bit implementation.
    
    Limitations:
    * Code is generated only in the medium code model, which
      is also gcc's default
    * Local symbols are not accessed directly, which seems to
      also be the case for 32-bit
    * LLVM does not work, but this does not work on 32-bit either
    * Must use the system runtime linker in GHCi, because the
      GHC linker for "static" object files (rts/Linker.c) for
      PPC 64-bit is not implemented. The system runtime
      (dynamic) linker works.
    * The handling of the system stack (register 1) is not ELF-
      compliant so stack traces break. Instead of allocating a new
      stack frame, spill code should use the "official" spill area
      in the current stack frame and deallocation code should restore
      the back chain
    * DWARF support is missing
    
    Fixes #9863
    
    Test Plan: validate (on powerpc, too)
    
    Reviewers: simonmar, trofi, erikd, austin
    
    Reviewed By: trofi
    
    Subscribers: bgamari, arnons1, kgardas, thomie
    
    Differential Revision: https://phabricator.haskell.org/D629
    
    GHC Trac Issues: #9863
    d3c1dda6
CodeGen.hs 72 KB