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  1. Jan 13, 2012
  2. Jan 10, 2012
  3. Jan 07, 2012
    • Evan Cheng's avatar
      Added a late machine instruction copy propagation pass. This catches · 00b1a3cd
      Evan Cheng authored
      opportunities that only present themselves after late optimizations
      such as tail duplication .e.g.
      ## BB#1:
              movl    %eax, %ecx
              movl    %ecx, %eax
              ret
      
      The register allocator also leaves some of them around (due to false
      dep between copies from phi-elimination, etc.)
      
      This required some changes in codegen passes. Post-ra scheduler and the
      pseudo-instruction expansion passes have been moved after branch folding
      and tail merging. They were before branch folding before because it did
      not always update block livein's. That's fixed now. The pass change makes
      independently since we want to properly schedule instructions after
      branch folding / tail duplication.
      
      rdar://10428165
      rdar://10640363
      
      llvm-svn: 147716
      00b1a3cd
  4. Dec 02, 2011
    • Nick Lewycky's avatar
      Move global variables in TargetMachine into new TargetOptions class. As an API · 50f02cb2
      Nick Lewycky authored
      change, now you need a TargetOptions object to create a TargetMachine. Clang
      patch to follow.
      
      One small functionality change in PTX. PTX had commented out the machine
      verifier parts in their copy of printAndVerify. That now calls the version in
      LLVMTargetMachine. Users of PTX who need verification disabled should rely on
      not passing the command-line flag to enable it.
      
      llvm-svn: 145714
      50f02cb2
  5. Nov 16, 2011
  6. Nov 02, 2011
    • Chandler Carruth's avatar
      Begin collecting some of the statistics for block placement discussed on · ae4e800c
      Chandler Carruth authored
      the mailing list. Suggestions for other statistics to collect would be
      awesome. =]
      
      Currently these are implemented as a separate pass guarded by a separate
      flag. I'm not thrilled by that, but I wanted to be able to collect the
      statistics for the old code placement as well as the new in order to
      have a point of comparison. I'm planning on folding them into the single
      pass if / when there is only one pass of interest.
      
      llvm-svn: 143537
      ae4e800c
  7. Oct 25, 2011
  8. Oct 21, 2011
    • Chandler Carruth's avatar
      Implement a block placement pass based on the branch probability and · 10281425
      Chandler Carruth authored
      block frequency analyses. This differs substantially from the existing
      block-placement pass in LLVM:
      
      1) It operates on the Machine-IR in the CodeGen layer. This exposes much
         more (and more precise) information and opportunities. Also, the
         results are more stable due to fewer transforms ocurring after the
         pass runs.
      2) It uses the generalized probability and frequency analyses. These can
         model static heuristics, code annotation derived heuristics as well
         as eventual profile loading. By basing the optimization on the
         analysis interface it can work from any (or a combination) of these
         inputs.
      3) It uses a more aggressive algorithm, both building chains from tho
         bottom up to maximize benefit, and using an SCC-based walk to layout
         chains of blocks in a profitable ordering without O(N^2) iterations
         which the old pass involves.
      
      The pass is currently gated behind a flag, and not enabled by default
      because it still needs to grow some important features. Most notably, it
      needs to support loop aligning and careful layout of loop structures
      much as done by hand currently in CodePlacementOpt. Once it supports
      these, and has sufficient testing and quality tuning, it should replace
      both of these passes.
      
      Thanks to Nick Lewycky and Richard Smith for help authoring & debugging
      this, and to Jakob, Andy, Eric, Jim, and probably a few others I'm
      forgetting for reviewing and answering all my questions. Writing
      a backend pass is *sooo* much better now than it used to be. =D
      
      llvm-svn: 142641
      10281425
  9. Oct 18, 2011
    • Nick Lewycky's avatar
      Add support for a new extension to the .file directive: · 40f8f2ff
      Nick Lewycky authored
        .file filenumber "directory" "filename"
      
      This removes one join+split of the directory+filename in MC internals. Because
      bitcode files have independent fields for directory and filenames in debug info,
      this patch may change the .o files written by existing .bc files.
      
      llvm-svn: 142300
      40f8f2ff
  10. Sep 30, 2011
  11. Sep 28, 2011
    • Bill Wendling's avatar
      Don't conditionalize execution of the SjLj EH prepare pass. · e6138e3a
      Bill Wendling authored
      We may need an SjLj EH preparation pass for some call site information, at least
      in the short term.
      
      llvm-svn: 140674
      e6138e3a
    • Bill Wendling's avatar
      This is the start of the new SjLj EH preparation pass, which will replace the · 354ff9e3
      Bill Wendling authored
      current IR-level pass.
      
      The old SjLj EH pass has some problems, especially with the new EH model. Most
      significantly, it violates some of the new restrictions the new model has. For
      instance, the 'dispatch' table wants to jump to the landing pad, but we cannot
      allow that because only an invoke's unwind edge can jump to a landing pad. This
      requires us to mangle the code something awful. In addition, we need to keep the
      now dead landingpad instructions around instead of CSE'ing them because the
      DWARF emitter uses that information (they are dead because no control flow edge
      will execute them - the control flow edge from an invoke's unwind is superceded
      by the edge coming from the dispatch).
      
      Basically, this pass belongs not at the IR level where SSA is king, but at the
      code-gen level, where we have more flexibility.
      
      llvm-svn: 140646
      354ff9e3
  12. Sep 25, 2011
  13. Sep 07, 2011
  14. Aug 24, 2011
  15. Aug 19, 2011
  16. Jul 26, 2011
  17. Jul 20, 2011
  18. Jul 19, 2011
  19. Jul 18, 2011
  20. Jul 15, 2011
  21. Jul 11, 2011
    • Evan Cheng's avatar
      - Eliminate MCCodeEmitter's dependency on TargetMachine. It now uses MCInstrInfo · c5e6d2f5
      Evan Cheng authored
        and MCSubtargetInfo.
      - Added methods to update subtarget features (used when targets automatically
        detect subtarget features or switch modes).
      - Teach X86Subtarget to update MCSubtargetInfo features bits since the
        MCSubtargetInfo layer can be shared with other modules.
      - These fixes .code 16 / .code 32 support since mode switch is updated in
        MCSubtargetInfo so MC code emitter can do the right thing.
      
      llvm-svn: 134884
      c5e6d2f5
  22. Jul 08, 2011
    • Evan Cheng's avatar
      Eliminate asm parser's dependency on TargetMachine: · 4d1ca96b
      Evan Cheng authored
      - Each target asm parser now creates its own MCSubtatgetInfo (if needed).
      - Changed AssemblerPredicate to take subtarget features which tablegen uses
        to generate asm matcher subtarget feature queries. e.g.
        "ModeThumb,FeatureThumb2" is translated to
        "(Bits & ModeThumb) != 0 && (Bits & FeatureThumb2) != 0".
      
      llvm-svn: 134678
      4d1ca96b
  23. Jul 06, 2011
  24. Jul 04, 2011
    • Rafael Espindola's avatar
      Move early tail duplication earlier. · c74d9378
      Rafael Espindola authored
      This fixes the issue noted in PR10251 where early tail dup of bbs with
      indirectbr would cause a bb to be duplicated into a loop preheader
      and then into its predecessors, creating phi nodes with identical
      operands just before register allocation.
      
      This helps with jsinterp.o size (__TEXT goes from 163568 to 126656)
      and a bit with performance 1.005x faster on sunspider (jits still enabled).
      
      The result on webkit with the jit disabled is more significant: 1.021x faster.
      
      llvm-svn: 134372
      c74d9378
  25. Jun 17, 2011
    • Bill Wendling's avatar
      b74b9de1
    • Bill Wendling's avatar
      Add an option that allows one to "decode" the LSDA. · e303114b
      Bill Wendling authored
      The LSDA is a bit difficult for the non-initiated to read. Even with comments,
      it's not always clear what's going on. This wraps the ASM streamer in a class
      that retains the LSDA and then emits a human-readable description of what's
      going on in it.
      
      So instead of having to make sense of:
      
      Lexception1:
              .byte   255
              .byte   155
              .byte   168
              .space  1
              .byte   3
              .byte   26
      Lset0 = Ltmp7-Leh_func_begin1
            .long     Lset0
      Lset1 = Ltmp812-Ltmp7
            .long     Lset1
      Lset2 = Ltmp913-Leh_func_begin1
            .long     Lset2
            .byte     3
      Lset3 = Ltmp812-Leh_func_begin1
            .long     Lset3
      Lset4 = Leh_func_end1-Ltmp812
            .long     Lset4
            .long     0
            .byte     0
            .byte     1
            .byte     0
            .byte     2
            .byte     125
            .long     __ZTIi@GOTPCREL+4
            .long     __ZTIPKc@GOTPCREL+4
      
      you can read this instead:
      
      ## Exception Handling Table: Lexception1
      ##  @LPStart Encoding: omit
      ##    @TType Encoding: indirect pcrel sdata4
      ##        @TType Base: 40 bytes
      ## @CallSite Encoding: udata4
      ## @Action Table Size: 26 bytes
      
      ## Action 1:
      ##   A throw between Ltmp7 and Ltmp812 jumps to Ltmp913 on an exception.
      ##     For type(s):  __ZTIi@GOTPCREL+4 __ZTIPKc@GOTPCREL+4
      ## Action 2:
      ##   A throw between Ltmp812 and Leh_func_end1 does not have a landing pad.
      
      llvm-svn: 133286
      e303114b
  26. Jun 16, 2011
  27. May 28, 2011
  28. May 22, 2011
  29. May 06, 2011
  30. Apr 30, 2011
  31. Mar 29, 2011
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