1. 04 Feb, 2009 2 commits
  2. 03 Feb, 2009 1 commit
  3. 02 Feb, 2009 1 commit
  4. 20 Jan, 2009 1 commit
  5. 16 Jan, 2009 1 commit
  6. 14 Jan, 2009 1 commit
  7. 10 Jan, 2009 1 commit
  8. 17 Oct, 2008 1 commit
  9. 16 Oct, 2008 1 commit
    • dias@eecs.harvard.edu's avatar
      Fixed linear regalloc bug, dropped some tracing code · c62b824e
      dias@eecs.harvard.edu authored
      o The linear-scan register allocator sometimes allocated a block
        before allocating one of its predecessors, which could lead
        to inconsistent allocations. Now, we allocate a block only
        if a predecessor has set the "incoming" assignments for the block
        (or if it's the procedure's entry block).
      o Also commented out some tracing code on the new codegen path.
      c62b824e
  10. 13 Oct, 2008 1 commit
    • dias@eecs.harvard.edu's avatar
      Big collection of patches for the new codegen branch. · e6243a81
      dias@eecs.harvard.edu authored
      o Fixed bug that emitted the copy-in code for closure entry
        in the wrong place -- at the initialization of the closure.
      o Refactored some of the closure entry code.
      o Added code to check that no LocalRegs are live-in to a procedure
         -- trip up some buggy programs earlier
      o Fixed environment bindings for thunks
         -- we weren't (re)binding the free variables in a thunk
      o Fixed a bug in proc-point splitting that dropped some updates
        to the entry block in a procedure.
      o Fixed improper calls to code that generates CmmLit's for strings
      o New invariant on cg_loc in CgIdInfo: the expression is always tagged
      o Code to load free vars on entry to a thunk was (wrongly) placed before
        the heap check.
      o Some of the StgCmm code was redundantly passing around Id's
        along with CgIdInfo's; no more.
      o Initialize the LocalReg's that point to a closure before allocating and
        initializing the closure itself -- otherwise, we have problems with
        recursive closure bindings
      o BlockEnv and BlockSet types are now abstract.
      o Update frames:
        - push arguments in Old call area
        - keep track of the return sp in the FCode monad
        - keep the return sp in every call, tail call, and return
            (because it might be different at different call sites,
             e.g. tail calls to the gc after a heap check are performed
                  before pushing the update frame)
        - set the sp appropriately on returns and tail calls
      o Reduce call, tail call, and return to a single LastCall node
      o Added slow entry code, using different calling conventions on entry and tail call
      o More fixes to the calling convention code.
        The tricky stuff is all about the closure environment: it must be passed in R1,
        but in non-closures, there is no such argument, so we can't treat all arguments
        the same way: the closure environment is special. Maybe the right step forward
        would be to define a different calling convention for closure arguments.
      o Let-no-escapes need to be emitted out-of-line -- otherwise, we drop code.
      o Respect RTS requirement of word alignment for pointers
        My stack allocation can pack sub-word values into a single word on the stack,
        but it wasn't requiring word-alignment for pointers. It does now,
        by word-aligning both pointer registers and call areas.
      o CmmLint was over-aggresively ruling out non-word-aligned memory references,
        which may be kosher now that we can spill small values into a single word.
      o Wrong label order on a conditional branch when compiling switches.
      o void args weren't dropped in many cases.
        To help prevent this kind of mistake, I defined a NonVoid wrapper,
        which I'm applying only to Id's for now, although there are probably
        other good candidates.
      o A little code refactoring: separate modules for procpoint analysis splitting, 
        stack layout, and building infotables.
      o Stack limit check: insert along with the heap limit check, using a symbolic
        constant (a special CmmLit), then replace it when the stack layout is known.
      o Removed last node: MidAddToContext 
      o Adding block id as a literal: means that the lowering of the calling conventions
        no longer has to produce labels early, which was inhibiting common-block elimination.
        Will also make it easier for the non-procpoint-splitting path.
      o Info tables: don't try to describe the update frame!
      o Over aggressive use of NonVoid!!!!
        Don't drop the non-void args before setting the type of the closure!!!
      o Sanity checking:
        Added a pass to stub dead dead slots on the stack
        (only ~10 lines with the dataflow framework)
      o More sanity checking:
        Check that incoming pointer arguments are non-stubbed.
        Note: these checks are still subject to dead-code removal, but they should
        still be quite helpful.
      o Better sanity checking: why stop at function arguments?
        Instead, in mkAssign, check that _any_ assignment to a pointer type is non-null
        -- the sooner the crash, the easier it is to debug.
        Still need to add the debugging flag to turn these checks on explicitly.
      o Fixed yet another calling convention bug.
        This time, the calls to the GC were wrong. I've added a new convention
        for GC calls and invoked it where appropriate.
        We should really straighten out the calling convention stuff:
          some of the code (and documentation) is spread across the compiler,
          and there's some magical use of the node register that should really
          be handled (not avoided) by calling conventions.
      o Switch bug: the arms in mkCmmLitSwitch weren't returning to a single join point.
      o Environment shadowing problem in Stg->Cmm:
        When a closure f is bound at the top-level, we should not bind f to the
        node register on entry to the closure.
        Why? Because if the body of f contains a let-bound closure g that refers
        to f, we want to make sure that it refers to the static closure for f.
        Normally, this would all be fine, because when we compile a closure,
        we rebind free variables in the environment. But f doesn't look like
        a free variable because it's a static value. So, the binding for f
        remains in the environment when we compile g, inconveniently referring
        to the wrong thing.
        Now, I bind the variable in the local environment only if the closure is not
        bound at the top level. It's still okay to make assumptions about the
        node holding the closure environment; we just won't find the binding
        in the environment, so code that names the closure will now directly
        get the label of the static closure, not the node register holding a
        pointer to the static closure.
      o Don't generate bogus Cmm code containing SRTs during the STG -> Cmm pass!
        The tables made reference to some labels that don't exist when we compute and
        generate the tables in the back end.
      o Safe foreign calls need some special treatment (at least until we have the integrated
        codegen). In particular:
        o they need info tables
        o they are not procpoints -- the successor had better be in the same procedure
        o we cannot (yet) implement the calling conventions early, which means we have
          to carry the calling-conv info all the way to the end
      o We weren't following the old convention when registering a module.
        Now, we use update frames to push any new modules that have to be registered
        and enter the youngest one on the stack.
        We also use the update frame machinery to specify that the return should pop
        the return address off the stack.
      o At each safe foreign call, an infotable must be at the bottom of the stack,
        and the TSO->sp must point to it.
      o More problems with void args in a direct call to a function:
        We were checking the args (minus voids) to check whether the call was saturated,
        which caused problems when the function really wasn't saturated because it
        took an extra void argument.
      o Forgot to distinguish integer != from floating != during Stg->Cmm
      o Updating slotEnv and areaMap to include safe foreign calls
        The dataflow analyses that produce the slotEnv and areaMap give
        results for each basic block, but we also need the results for
        a safe foreign call, which is a middle node.
        After running the dataflow analysis, we have another pass that
        updates the results to includ any safe foreign calls.
      o Added a static flag for the debugging technique that inserts
        instructions to stub dead slots on the stack and crashes when
        a stubbed value is loaded into a pointer-typed LocalReg.
      o C back end expects to see return continuations before their call sites.
        Sorted the flowgraphs appropriately after splitting.
      o PrimOp calling conventions are special -- unlimited registers, no stack
        Yet another calling convention...
      o More void value problems: if the RHS of a case arm is a void-typed variable,
        don't try to return it.
      o When calling some primOp, they may allocate memory; if so, we need to
        do a heap check when we return from the call.
      e6243a81
  11. 31 Jul, 2008 1 commit
  12. 21 Jul, 2008 1 commit
  13. 29 May, 2008 1 commit
    • dias@eecs.harvard.edu's avatar
      Replacing copyins and copyouts with data-movement instructions · 0d80489c
      dias@eecs.harvard.edu authored
      o Moved BlockId stuff to a new file to avoid module recursion
      o Defined stack areas for parameter-passing locations and spill slots
      o Part way through replacing copy in and copy out nodes
        - added movement instructions for stack pointer
        - added movement instructions for call and return parameters
          (but not with the proper calling conventions)
      o Inserting spills and reloads for proc points is now procpoint-aware
        (it was relying on the presence of a CopyIn node as a proxy for
         procpoint knowledge)
      o Changed ZipDataflow to expect AGraphs (instead of being polymorphic in
         the type of graph)
      0d80489c
  14. 30 Apr, 2008 1 commit
    • Ian Lynagh's avatar
      Update a panic message · 7dd753a0
      Ian Lynagh authored
      It was (panic "RegisterAlloc.joinToTargets"), but had since moved to
      RegAllocLinear.makeRegMovementGraph.
      7dd753a0
  15. 12 Apr, 2008 1 commit
  16. 29 Mar, 2008 2 commits
  17. 07 Feb, 2008 2 commits
  18. 02 Jan, 2008 1 commit
  19. 05 Oct, 2007 1 commit
  20. 21 Sep, 2007 1 commit
  21. 08 Sep, 2007 1 commit
  22. 07 Sep, 2007 2 commits
    • nr@eecs.harvard.edu's avatar
      a good deal of salutory renaming · fd8d0411
      nr@eecs.harvard.edu authored
      I've renamed a number of type and data constructors within Cmm so that
      the names used in the compiler may more closely reflect the C--
      specification 2.1.  I've done a bit of other renaming as well.
      Highlights:
      
        CmmFormal and CmmActual now bear a CmmKind (which for now is a
                                                    MachHint as before)
        CmmFormals = [CmmFormal] and CmmActuals = [CmmActual]
        
        suitable changes have been made to both code and nonterminals in the
        Cmm parser (which is as yet untested)
      
        For reasons I don't understand, parts of the code generator use a
        sequence of 'formal parameters' with no C-- kinds.  For these we now
        have the types
          type CmmFormalWithoutKind   = LocalReg
          type CmmFormalsWithoutKinds = [CmmFormalWithoutKind]
      
        A great many appearances of (Tau, MachHint) have been simplified to
        the appropriate CmmFormal or CmmActual, though I'm sure there are
        more opportunities.
      
        Kind and its data constructors are now renamed to
           data GCKind = GCKindPtr | GCKindNonPtr 
        to avoid confusion with the Kind used in the type checker and with CmmKind.
      
      Finally, in a somewhat unrelated bit (and in honor of Simon PJ, who
      thought of the name), the Whalley/Davidson 'transaction limit' is now
      called 'OptimizationFuel' with the net effect that there are no longer
      two unrelated uses of the abbreviation 'tx'.
      
      fd8d0411
    • simonpj@microsoft.com's avatar
      Warning police · 8672676c
      simonpj@microsoft.com authored
      8672676c
  23. 05 Sep, 2007 3 commits
  24. 04 Sep, 2007 1 commit
  25. 03 Sep, 2007 1 commit
  26. 01 Sep, 2007 1 commit
  27. 24 Aug, 2007 1 commit
  28. 23 Aug, 2007 1 commit
  29. 22 Aug, 2007 1 commit
  30. 21 Aug, 2007 1 commit
  31. 14 Aug, 2007 1 commit
    • Ben.Lippmeier@anu.edu.au's avatar
      Add graph coloring register allocator. · 0f7d268d
      Ben.Lippmeier@anu.edu.au authored
      Refactored linear allocator into separate liveness annotation and allocation stages.
      Added graph coloring allocator, use -fregs-graph to enable.
        New dump flags are
          -ddump-asm-native          -- output of cmm -> native transform.
          -ddump-asm-liveness        -- code annotated with register liveness info
          -ddump-asm-coalesce        -- output of register move coalescing
                                          (this is a separate pass when using the coloring allocator)
                                          (this could change in the future)
          -ddump-asm-regalloc        -- code after register allocation
          -ddump-asm-regalloc-stages -- blocks after each build/spill stage of coloring allocator
          -ddump-asm-conflicts       -- a global register liveness graph in graphviz format 
              
      The new register allocator will allocate some registers, but it's not
      quite ready for prime-time yet. The spill code generator needs some work...
      0f7d268d
  32. 14 Jul, 2007 1 commit
    • Clemens Fruhwirth's avatar
      joinToTargets to emit fixup code even when movement graph contains cycles · 64f0661e
      Clemens Fruhwirth authored
      First, cycles can only start of with registers and their destination
      must involve a register location. This is because memory locations are
      allocated exclusively for a virtual register and hence can never cause
      a conflict in the assignment, hence need no fixup code. Therefore, we
      only have to deal with InReg -> InReg, or InReg -> InReg/InMem
      movements.  
      
      The strategy is to take the first cycle element, which is guaranteed
      to start with a register, spill it to a fresh memory location, compute
      the fixup for the rest, and restore from the spill slot to its
      destinations. The "rest" will degenerate into an acyclic scc, so we do
      not need take care of the empty list case in CyclicScc. 
       ***END OF DESCRIPTION***
      
      Place the long patch description above the ***END OF DESCRIPTION*** marker.
      The first line of this file will be the patch name.
      
      
      This patch contains the following changes:
      
      M ./compiler/nativeGen/RegisterAlloc.hs -6 +27
      64f0661e
  33. 05 Jul, 2007 1 commit
  34. 23 Jan, 2007 1 commit
    • Simon Marlow's avatar
      Fix a bug in the liveness analysis · 79791534
      Simon Marlow authored
      We were being overly conservative, registers that were live only at a
      branch target were not recorded as being dead in the branch-not-taken
      code.
      79791534