Michael Gottesman e7a1e3ee82 [block-freq] Add BlockFrequency::scale that returns a remainder from the division and make the private scale in BlockFrequency more performant. ... This change is the first in a series of changes improving LLVM's Block Frequency propogation implementation to not lose probability mass in branchy code when propogating block frequency information from a basic block to its successors. This patch is a simple infrastructure improvement that does not actually modify the block frequency algorithm. The specific changes are: 1. Changes the division algorithm used when scaling block frequencies by branch probabilities to a short division algorithm. This gives us the remainder for free as well as provides a nice speed boost. When I benched the old routine and the new routine on a Sandy Bridge iMac with disabled turbo mode performing 8192 iterations on an array of length 32768, I saw ~600% increase in speed in mean/median performance. 2. Exposes a scale method that returns a remainder. This is important so we can ensure that when we scale a block frequency by some branch probability BP = N/D, the remainder from the division by D can be retrieved and propagated to other children to ensure no probability mass is lost (more to come on this). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194950 91177308-0d34-0410-b5e6-96231b3b80d8		2013-11-17 03:25:24 +00:00
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ADT	[weak vtables] Remove a bunch of weak vtables	2013-11-15 22:34:48 +00:00
Analysis	Fix an oversight in isPotentiallyReachable where we wouldn't do any CFG-walking	2013-08-13 00:03:47 +00:00
Bitcode	llvm/unittests: Use OwningPtr to fix --vg-leak.	2013-01-23 08:33:13 +00:00
CodeGen	DIEHash: Summary hashing of member functions	2013-10-25 20:04:25 +00:00
DebugInfo	DWARF parser: propery handle DW_FORM_ref_sig8 and fix Windows build.	2013-10-29 16:32:19 +00:00
ExecutionEngine	[weak vtables] Remove a bunch of weak vtables	2013-11-15 22:34:48 +00:00
IR	[PM] Completely remove support for explicit 'require' methods on the	2013-11-17 03:18:05 +00:00
MC	Fix MCDataAtom never calling remap when adding data.	2013-10-16 18:26:16 +00:00
Object	Update incorrect file headers.	2013-08-01 18:42:28 +00:00
Option	Option parsing: support case-insensitive option matching.	2013-08-28 20:04:31 +00:00
Support	[block-freq] Add BlockFrequency::scale that returns a remainder from the division and make the private scale in BlockFrequency more performant.	2013-11-17 03:25:24 +00:00
Transforms	Introduce SpecialCaseList::isIn overload for GlobalAliases.	2013-08-19 19:00:35 +00:00
CMakeLists.txt	Fix MCDataAtom never calling remap when adding data.	2013-10-16 18:26:16 +00:00
Makefile	Revert "Move copying of global initializers below the cloning of functions."	2013-11-09 00:43:18 +00:00
Makefile.unittest	build/unittests: Fix llvm-config names for gtest libraries, and bring Makefile	2011-12-15 23:35:08 +00:00