llvm-6502/test/Analysis
Andrea Di Biagio 60e9a53c21 [CostModel][x86] Improved cost model for alternate shuffles.
This patch:
 1) Improves the cost model for x86 alternate shuffles (originally
added at revision 211339);
 2) Teaches the Cost Model Analysis pass how to analyze alternate shuffles.

Alternate shuffles are a special kind of blend; on x86, we can often
easily lowered alternate shuffled into single blend
instruction (depending on the subtarget features).

The existing cost model didn't take into account subtarget features.
Also, it had a couple of "dead" entries for vector types that are never
legal (example: on x86 types v2i32 and v2f32 are not legal; those are
always either promoted or widened to 128-bit vector types).

The new x86 cost model takes into account what target features we have
before returning the shuffle cost (i.e. the number of instructions
after the blend is lowered/expanded).

This patch also teaches the Cost Model Analysis how to identify and analyze
alternate shuffles (i.e. 'SK_Alternate' shufflevector instructions):
 - added function 'isAlternateVectorMask';
 - added some logic to check if an instruction is a alternate shuffle and, in
   case, call the target specific TTI to get the corresponding shuffle cost;
 - added a test to verify the cost model analysis on alternate shuffles.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212296 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-03 22:24:18 +00:00
..
BasicAA
BlockFrequencyInfo Fix typos 2014-05-15 01:52:21 +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 [CostModel][x86] Improved cost model for alternate shuffles. 2014-07-03 22:24:18 +00:00
Delinearization ScalarEvolution: Derive element size from the type of the loaded element 2014-06-08 19:21:20 +00:00
DependenceAnalysis remove constant terms 2014-05-27 22:41:45 +00:00
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 Adding testcase for PR18886. 2014-05-27 06:44:25 +00:00
TypeBasedAliasAnalysis