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mirror of https://github.com/RPCS3/llvm.git synced 2024-12-30 08:24:12 +00:00
llvm/lib/Analysis
Eli Friedman b42a626122 PR2621: Improvements to the SCEV AddRec binomial expansion. This
version uses a new algorithm for evaluating the binomial coefficients 
which is significantly more efficient for AddRecs of more than 2 terms 
(see the comments in the code for details on how the algorithm works).  
It also fixes some bugs: it removes the arbitrary length restriction for 
AddRecs, it fixes the silent generation of incorrect code for AddRecs 
which require a wide calculation width, and it fixes an issue where we 
were incorrectly truncating the iteration count too far when evaluating 
an AddRec expression narrower than the induction variable.

There are still a few related issues I know of: I think there's 
still an issue with the SCEVExpander expansion of AddRec in terms of
the width of the induction variable used.  The hack to avoid generating 
too-wide integers shouldn't be necessary; instead, the callers should be 
considering the cost of the expansion before expanding it (in addition 
to not expanding too-wide integers, we might not want to expand 
expressions that are really expensive, especially when optimizing for 
size; calculating an length-17 32-bit AddRec currently generates about 250 
instructions of straight-line code on X86).  Also, for long 32-bit 
AddRecs on X86, CodeGen really sucks at scheduling the code.  I'm planning on 
filing follow-up PRs for these issues.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54332 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-04 23:49:06 +00:00
..
IPA Replace two manual loops with calls to CallSite::hasArguments (no functional changes). 2008-06-04 16:57:50 +00:00
AliasAnalysis.cpp Fix a copy+paste error in a comment. 2008-05-30 00:02:02 +00:00
AliasAnalysisCounter.cpp
AliasAnalysisEvaluator.cpp
AliasDebugger.cpp
AliasSetTracker.cpp
Analysis.cpp
BasicAliasAnalysis.cpp simplify some code by using a helper function. This really really 2008-06-16 06:38:26 +00:00
CFGPrinter.cpp
ConstantFolding.cpp Fix minor issues with VICmp/VFCmp constant expressions 2008-07-25 17:35:37 +00:00
InstCount.cpp
Interval.cpp
IntervalPartition.cpp fix warning when assertions disabled. 2008-06-21 19:48:22 +00:00
LibCallAliasAnalysis.cpp Expose a public interface to this pass. 2008-06-05 23:45:18 +00:00
LibCallSemantics.cpp
LoadValueNumbering.cpp Use find instead of lower_bound. 2008-07-11 20:58:19 +00:00
LoopInfo.cpp
LoopPass.cpp Fix spelling of "hierarchy" in comments. 2008-07-11 22:51:32 +00:00
LoopVR.cpp Add a value range analysis that lazily computes ranges using ScalarEvolutions. 2008-06-30 00:04:21 +00:00
Makefile
MemoryDependenceAnalysis.cpp Fix a subtle bug when removing instructions from memdep. In very specific 2008-07-28 16:00:58 +00:00
PostDominators.cpp Add newline at end of file. 2008-05-29 21:05:16 +00:00
ProfileInfo.cpp
ProfileInfoLoader.cpp
ProfileInfoLoaderPass.cpp
ScalarEvolution.cpp PR2621: Improvements to the SCEV AddRec binomial expansion. This 2008-08-04 23:49:06 +00:00
ScalarEvolutionExpander.cpp Expand SCEVUDiv of power of 2 to a lshr instruction. 2008-07-08 05:05:37 +00:00
SparsePropagation.cpp Use Function::getEntryBlock instead of Function::begin, for clarity. 2008-05-27 20:55:29 +00:00
Trace.cpp
ValueNumbering.cpp Update comments and documentation to reflect that GCSE and ValueNumbering are 2008-06-05 07:55:49 +00:00
ValueTracking.cpp Don't use ++idx_begin when I actually mean idx_begin + 1, especially since we 2008-07-16 10:47:35 +00:00