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  1. Nov 26, 2008
  2. Nov 18, 2008
  3. Oct 27, 2008
  4. Oct 21, 2008
    • Dan Gohman's avatar
      Optimized FCMP_OEQ and FCMP_UNE for x86. · 97d95d6d
      Dan Gohman authored
      Where previously LLVM might emit code like this:
      
              ucomisd %xmm1, %xmm0
              setne   %al
              setp    %cl
              orb     %al, %cl
              jne     .LBB4_2
      
      it now emits this:
      
              ucomisd %xmm1, %xmm0
              jne     .LBB4_2
              jp      .LBB4_2
      
      It has fewer instructions and uses fewer registers, but it does
      have more branches. And in the case that this code is followed by
      a non-fallthrough edge, it may be followed by a jmp instruction,
      resulting in three branch instructions in sequence. Some effort
      is made to avoid this situation.
      
      To achieve this, X86ISelLowering.cpp now recognizes FCMP_OEQ and
      FCMP_UNE in lowered form, and replace them with code that emits
      two branches, except in the case where it would require converting
      a fall-through edge to an explicit branch.
      
      Also, X86InstrInfo.cpp's branch analysis and transform code now
      knows now to handle blocks with multiple conditional branches. It
      uses loops instead of having fixed checks for up to two
      instructions. It can now analyze and transform code generated
      from FCMP_OEQ and FCMP_UNE.
      
      llvm-svn: 57873
      97d95d6d
  5. Oct 17, 2008
  6. Oct 16, 2008
  7. Oct 11, 2008
  8. Oct 03, 2008
  9. Sep 30, 2008
  10. Sep 23, 2008
  11. Aug 30, 2008
  12. Aug 29, 2008
  13. Aug 26, 2008
  14. Aug 15, 2008
  15. Jul 08, 2008
    • Dan Gohman's avatar
      Pool-allocation for MachineInstrs, MachineBasicBlocks, and · 3b460303
      Dan Gohman authored
      MachineMemOperands. The pools are owned by MachineFunctions.
      
      This drastically reduces the number of calls to malloc/free made
      during the "Emit" phase of scheduling, as well as later phases
      in CodeGen. Combined with other changes, this speeds up the
      "instruction selection" phase of CodeGen by 10% in some cases.
      
      llvm-svn: 53212
      3b460303
  16. Jul 03, 2008
  17. Jun 28, 2008
  18. Jun 16, 2008
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  20. May 12, 2008
  21. Apr 16, 2008
  22. Mar 31, 2008
  23. Mar 25, 2008
  24. Mar 13, 2008
    • Christopher Lamb's avatar
      Get rid of a pseudo instruction and replace it with subreg based operation on... · dd55d3f1
      Christopher Lamb authored
      Get rid of a pseudo instruction and replace it with subreg based operation on real instructions, ridding the asm printers of the hack used to do this previously. In the process, update LowerSubregs to be careful about eliminating copies that have side affects. 
      
      Note: the coalescer will have to be careful about this too, when it starts coalescing insert_subreg nodes.
      llvm-svn: 48329
      dd55d3f1
  25. Mar 11, 2008
  26. Mar 10, 2008
  27. Mar 01, 2008
  28. Feb 10, 2008
  29. Feb 08, 2008
  30. Jan 11, 2008
    • Chris Lattner's avatar
      Simplify the side effect stuff a bit more and make licm/sinking · c8226f32
      Chris Lattner authored
      both work right according to the new flags.
      
      This removes the TII::isReallySideEffectFree predicate, and adds
      TII::isInvariantLoad. 
      
      It removes NeverHasSideEffects+MayHaveSideEffects and adds
      UnmodeledSideEffects as machine instr flags.  Now the clients
      can decide everything they need.
      
      I think isRematerializable can be implemented in terms of the
      flags we have now, though I will let others tackle that.
      
      llvm-svn: 45843
      c8226f32
  31. Jan 07, 2008
  32. Jan 05, 2008
  33. Jan 02, 2008
  34. Jan 01, 2008
  35. Dec 31, 2007
  36. Dec 30, 2007
    • Bill Wendling's avatar
      If we have a load of a global address that's not modified during the · 7749a901
      Bill Wendling authored
      function, then go ahead and hoist it out of the loop. This is the result:
      
      $ cat a.c
      volatile int G;
      
      int A(int N) {
        for (; N > 0; --N)
          G++;
      }
      $ llc -o - -relocation-model=pic
      _A:
      ...
      LBB1_2: # bb
              movl    L_G$non_lazy_ptr-"L1$pb"(%eax), %esi
              incl    (%esi)
              incl    %edx
              cmpl    %ecx, %edx
              jne     LBB1_2  # bb
      ...
      $ llc -o - -relocation-model=pic -machine-licm
      _A:
      ...
              movl    L_G$non_lazy_ptr-"L1$pb"(%eax), %eax
      LBB1_2: # bb
              incl    (%eax)
              incl    %edx
              cmpl    %ecx, %edx
              jne     LBB1_2  # bb
      ...
      
      I'm limiting this to the MOV32rm x86 instruction for now.
      
      llvm-svn: 45444
      7749a901
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