Duncan P. N. Exon Smith d905bba691 blockfreq: Approximate irreducible control flow ... Previously, irreducible backedges were ignored. With this commit, irreducible SCCs are discovered on the fly, and modelled as loops with multiple headers. This approximation specifies the headers of irreducible sub-SCCs as its entry blocks and all nodes that are targets of a backedge within it (excluding backedges within true sub-loops). Block frequency calculations act as if we insert a new block that intercepts all the edges to the headers. All backedges and entries to the irreducible SCC point to this imaginary block. This imaginary block has an edge (with even probability) to each header block. The result is now reasonable enough that I've added a number of testcases for irreducible control flow. I've outlined in `BlockFrequencyInfoImpl.h` ways to improve the approximation. <rdar://problem/14292693> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207286 91177308-0d34-0410-b5e6-96231b3b80d8		2014-04-25 23:08:57 +00:00
..
BasicAA	PR15967 Fix in basicaa for faulty returning no alias.	2014-03-26 21:30:19 +00:00
BlockFrequencyInfo	blockfreq: Approximate irreducible control flow	2014-04-25 23:08:57 +00:00
BranchProbabilityInfo	Fix a bug in which BranchProbabilityInfo wasn't setting branch weights of basic blocks inside loops correctly.	2014-04-14 16:56:19 +00:00
CallGraph
CostModel	Don't assert in BasicTTI::getMemoryOpCost for non-simple types	2014-04-14 05:59:09 +00:00
Delinearization	in findGCD of multiply expr return the gcd	2014-04-08 21:21:05 +00:00
DependenceAnalysis
Dominators
GlobalsModRef
LazyCallGraph	[LCG] Add support for building persistent and connected SCCs to the	2014-04-18 10:50:32 +00:00
Lint
LoopInfo
MemoryDependenceAnalysis
PostDominators
RegionInfo
ScalarEvolution
TypeBasedAliasAnalysis