Skip to content
  1. Jan 30, 2012
  2. Jan 29, 2012
  3. Jan 28, 2012
  4. Jan 27, 2012
  5. Jan 26, 2012
  6. Jan 25, 2012
  7. Jan 24, 2012
  8. Jan 23, 2012
  9. Jan 20, 2012
    • David Blaikie's avatar
      More dead code removal (using -Wunreachable-code) · 46a9f016
      David Blaikie authored
      llvm-svn: 148578
      46a9f016
    • Andrew Trick's avatar
      Handle a corner case with IV chain collection with bailout instead of assert. · b9c822ab
      Andrew Trick authored
      Fixes PR11783: bad cast to AddRecExpr.
      
      llvm-svn: 148572
      b9c822ab
    • Kostya Serebryany's avatar
      Extend Attributes to 64 bits · a5054ad2
      Kostya Serebryany authored
      Problem: LLVM needs more function attributes than currently available (32 bits).
      One such proposed attribute is "address_safety", which shows that a function is being checked for address safety (by AddressSanitizer, SAFECode, etc).
      
      Solution:
      - extend the Attributes from 32 bits to 64-bits
      - wrap the object into a class so that unsigned is never erroneously used instead
      - change "unsigned" to "Attributes" throughout the code, including one place in clang.
      - the class has no "operator uint64 ()", but it has "uint64_t Raw() " to support packing/unpacking.
      - the class has "safe operator bool()" to support the common idiom:  if (Attributes attr = getAttrs()) useAttrs(attr);
      - The CTOR from uint64_t is marked explicit, so I had to add a few explicit CTOR calls
      - Add the new attribute "address_safety". Doing it in the same commit to check that attributes beyond first 32 bits actually work.
      - Some of the functions from the Attribute namespace are worth moving inside the class, but I'd prefer to have it as a separate commit.
      
      Tested:
      "make check" on Linux (32-bit and 64-bit) and Mac (10.6)
      built/run spec CPU 2006 on Linux with clang -O2.
      
      
      This change will break clang build in lib/CodeGen/CGCall.cpp.
      The following patch will fix it.
      
      llvm-svn: 148553
      a5054ad2
    • Andrew Trick's avatar
      SCEVExpander fixes. Affects LSR and indvars. · c908b43d
      Andrew Trick authored
      LSR has gradually been improved to more aggressively reuse existing code, particularly existing phi cycles. This exposed problems with the SCEVExpander's sloppy treatment of its insertion point. I applied some rigor to the insertion point problem that will hopefully avoid an endless bug cycle in this area. Changes:
      
      - Always used properlyDominates to check safe code hoisting.
      
      - The insertion point provided to SCEV is now considered a lower bound. This is usually a block terminator or the use itself. Under no cirumstance may SCEVExpander insert below this point.
      
      - LSR is reponsible for finding a "canonical" insertion point across expansion of different expressions.
      
      - Robust logic to determine whether IV increments are in "expanded" form and/or can be safely hoisted above some insertion point.
      
      Fixes PR11783: SCEVExpander assert.
      
      llvm-svn: 148535
      c908b43d
  10. Jan 19, 2012
  11. Jan 18, 2012
  12. Jan 17, 2012
  13. Jan 16, 2012
  14. Jan 15, 2012
  15. Jan 14, 2012
  16. Jan 13, 2012
  17. Jan 11, 2012
  18. Jan 10, 2012
    • Andrew Trick's avatar
      Enable LSR IV Chains with sufficient heuristics. · d5d2db9a
      Andrew Trick authored
      These heuristics are sufficient for enabling IV chains by
      default. Performance analysis has been done for i386, x86_64, and
      thumbv7. The optimization is rarely important, but can significantly
      speed up certain cases by eliminating spill code within the
      loop. Unrolled loops are prime candidates for IV chains. In many
      cases, the final code could still be improved with more target
      specific optimization following LSR. The goal of this feature is for
      LSR to make the best choice of induction variables.
      
      Instruction selection may not completely take advantage of this
      feature yet. As a result, there could be cases of slight code size
      increase.
      
      Code size can be worse on x86 because it doesn't support postincrement
      addressing. In fact, when chains are formed, you may see redundant
      address plus stride addition in the addressing mode. GenerateIVChains
      tries to compensate for the common cases.
      
      On ARM, code size increase can be mitigated by using postincrement
      addressing, but downstream codegen currently misses some opportunities.
      
      llvm-svn: 147826
      d5d2db9a
  19. Jan 09, 2012
    • Andrew Trick's avatar
      Adding IV chain generation to LSR. · 248d410e
      Andrew Trick authored
      After collecting chains, check if any should be materialized. If so,
      hide the chained IV users from the LSR solver. LSR will only solve for
      the head of the chain. GenerateIVChains will then materialize the
      chained IV users by computing the IV relative to its previous value in
      the chain.
      
      In theory, chained IV users could be exposed to LSR's solver. This
      would be considerably complicated to implement and I'm not aware of a
      case where we need it. In practice it's more important to
      intelligently prune the search space of nontrivial loops before
      running the solver, otherwise the solver is often forced to prune the
      most optimal solutions. Hiding the chained users does this well, so
      that LSR is more likely to find the best IV for the chain as a whole.
      
      llvm-svn: 147801
      248d410e
Loading