[commit: ghc] master: llvmGen: Compatibility with LLVM 3.5 (re #9142) (e16a342)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/e16a342d70b92fc8480793d3ec911853f0c31e44/ghc

>---------------------------------------------------------------

commit e16a342d70b92fc8480793d3ec911853f0c31e44
Author: Ben Gamari <bgamari.foss at gmail.com>
Date:   Fri Nov 21 21:05:25 2014 +0100

    llvmGen: Compatibility with LLVM 3.5 (re #9142)
    
    Due to changes in LLVM 3.5 aliases now may only refer to definitions.
    Previously to handle symbols defined outside of the current commpilation
    unit GHC would emit both an `external` declaration, as well as an alias
    pointing to it, e.g.,
    
        @stg_BCO_info = external global i8
        @stg_BCO_info$alias = alias private i8* @stg_BCO_info
    
    Where references to `stg_BCO_info` will use the alias
    `stg_BCO_info$alias`. This is not permitted under the new alias
    behavior, resulting in errors resembling,
    
        Alias must point to a definition
        i8* @"stg_BCO_info$alias"
    
    To fix this, we invert the naming relationship between aliases and
    definitions. That is, now the symbol definition takes the name
    `@stg_BCO_info$def` and references use the actual name, `@stg_BCO_info`.
    This means the external symbols can be handled by simply emitting an
    `external` declaration,
    
        @stg_BCO_info = external global i8
    
    Whereas in the case of a forward declaration we emit,
    
        @stg_BCO_info = alias private i8* @stg_BCO_info$def
    
    Reviewed By: austin
    
    Differential Revision: https://phabricator.haskell.org/D155


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e16a342d70b92fc8480793d3ec911853f0c31e44
 compiler/llvmGen/Llvm/Types.hs       |   3 +-
 compiler/llvmGen/LlvmCodeGen.hs      |   5 +-
 compiler/llvmGen/LlvmCodeGen/Base.hs | 102 +++++++++++++++++++++++++++++------
 compiler/llvmGen/LlvmCodeGen/Data.hs |  10 ++--
 compiler/llvmGen/LlvmCodeGen/Ppr.hs  |  38 ++++++++++---
 5 files changed, 127 insertions(+), 31 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc e16a342d70b92fc8480793d3ec911853f0c31e44