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  1. Feb 16, 2012
    • Akira Hatanaka's avatar
      Remove trailing whitespace. Add newline. · 4705b0cc
      Akira Hatanaka authored
      llvm-svn: 150706
      4705b0cc
    • Lang Hames's avatar
      55a2a961
    • Lang Hames's avatar
      FPSCR shouldn't be reserved. · 11ca986b
      Lang Hames authored
      llvm-svn: 150654
      11ca986b
    • Jakob Stoklund Olesen's avatar
      Enable register mask operands for x86 calls. · 8a450cb2
      Jakob Stoklund Olesen authored
      Call instructions no longer have a list of 43 call-clobbered registers.
      Instead, they get a single register mask operand with a bit vector of
      call-preserved registers.
      
      This saves a lot of memory, 42 x 32 bytes = 1344 bytes per call
      instruction, and it speeds up building call instructions because those
      43 imp-def operands no longer need to be added to use-def lists. (And
      removed and shifted and re-added for every explicit call operand).
      
      Passes like LiveVariables, LiveIntervals, RAGreedy, PEI, and
      BranchFolding are significantly faster because they can deal with call
      clobbers in bulk.
      
      Overall, clang -O2 is between 0% and 8% faster, uniformly distributed
      depending on call density in the compiled code.  Debug builds using
      clang -O0 are 0% - 3% faster.
      
      I have verified that this patch doesn't change the assembly generated
      for the LLVM nightly test suite when building with -disable-copyprop
      and -disable-branch-fold.
      
      Branch folding behaves slightly differently in a few cases because call
      instructions have different hash values now.
      
      Copy propagation flushes its data structures when it crosses a register
      mask operand. This causes it to leave a few dead copies behind, on the
      order of 20 instruction across the entire nightly test suite, including
      SPEC. Fixing this properly would require the pass to use different data
      structures.
      
      llvm-svn: 150638
      8a450cb2
  2. Feb 15, 2012
  3. Feb 14, 2012
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