[M3commit] [modula3/cm3] 80fac0: In M3CG_LLVM, function DebugObject, extensive rewo...

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/modula3/cm3
  Commit: 80fac04c0ba0e2d87cb03c7d16532211b014e159
      https://github.com/modula3/cm3/commit/80fac04c0ba0e2d87cb03c7d16532211b014e159
  Author: Rodney Bates <rodney.m.bates at acm.org>
  Date:   2016-02-27 (Sat, 27 Feb 2016)

  Changed paths:
    M m3-sys/llvm3.6.1/src/M3CG_LLVM.m3

  Log Message:
  -----------
  In M3CG_LLVM, function DebugObject, extensive rework.

This function was a hastily cobbled-up mess that resulted from a
merge during the change to llvm-3.6.1, patched to just compile.
This change cleans it up greatly.  It necessarily uses the newly-
bound replaceAllUsesWith on MDNodes, because there is a very
local cycle in building object type debug info with a supertype.

More needs to be done with nonlocal cycles, predefined object types,
and the supertype of TEXT is questionable.  Also, DebugRecord is
a similar poorly merged mess.