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  1. Jun 06, 2017
    • Davide Italiano's avatar
      [SelectionDAG] Update the dominator after splitting critical edges. · fb4d5c09
      Davide Italiano authored 
      Running `llc -verify-dom-info` on the attached testcase results in a
crash in the verifier, due to a stale dominator tree.

i.e.

  DominatorTree is not up to date!
  Computed:
  =============================--------------------------------
  Inorder Dominator Tree:
    [1] %safe_mod_func_uint8_t_u_u.exit.i.i.i {0,7}
      [2] %lor.lhs.false.i61.i.i.i {1,2}
      [2] %safe_mod_func_int8_t_s_s.exit.i.i.i {3,6}
        [3] %safe_div_func_int64_t_s_s.exit66.i.i.i {4,5}

  Actual:
  =============================--------------------------------
  Inorder Dominator Tree:
    [1] %safe_mod_func_uint8_t_u_u.exit.i.i.i {0,9}
      [2] %lor.lhs.false.i61.i.i.i {1,2}
      [2] %safe_mod_func_int8_t_s_s.exit.i.i.i {3,8}
        [3] %safe_div_func_int64_t_s_s.exit66.i.i.i {4,5}
        [3] %safe_mod_func_int8_t_s_s.exit.i.i.i.lor.lhs.false.i61.i.i.i_crit_edge {6,7}

This is because in `SelectionDAGIsel` we split critical edges without
updating the corresponding dominator for the function (and we claim
in `MachineFunctionPass::getAnalysisUsage()` that the domtree is preserved).

We could either stop preserving the domtree in `getAnalysisUsage`
or tell `splitCriticalEdge()` to update it.
As the second option is easy to implement, that's the one I chose.

Differential Revision:  https://reviews.llvm.org/D33800

llvm-svn: 304742
      fb4d5c09
    • Zachary Turner's avatar
      [CodeView] Fix endianness bug. · 88101dad
      Zachary Turner authored 
      We should be outputting in little endian, but we were writing
in host endianness.

llvm-svn: 304741
      88101dad
    • Richard Smith's avatar
      Fix memory leak exposed by r304726. · f878a84c
      Richard Smith authored 
      When giving a ContentCache a null buffer, ignore the DoNotFree flag rather than
inheriting it onto whatever buffer we end up using for the file. Also ensure
that the main buffer is properly destroyed.

llvm-svn: 304740
      f878a84c
  3. Jun 05, 2017