Quentin Colombet 4c2a2ac196 [LiveIntervalAnalysis] Speed up creation of live ranges for physical registers ... by using a segment set. The patch addresses a compile-time performance regression in the LiveIntervals analysis pass (see http://llvm.org/bugs/show_bug.cgi?id=18580). This regression is especially critical when compiling long functions. Our analysis had shown that the most of time is taken for generation of live intervals for physical registers. Insertions in the middle of the array of live ranges cause quadratic algorithmic complexity, which is apparently the main reason for the slow-down. Overview of changes: - The patch introduces an additional std::set<Segment>* member in LiveRange for storing segments in the phase of initial creation. The set is used if this member is not NULL, otherwise everything works the old way. - The set of operations on LiveRange used during initial creation (i.e. used by createDeadDefs and extendToUses) have been reimplemented to use the segment set if it is available. - After a live range is created the contents of the set are flushed to the segment vector, because the set is not as efficient as the vector for the later uses of the live range. After the flushing, the set is deleted and cannot be used again. - The set is only for live ranges computed in LiveIntervalAnalysis::computeLiveInRegUnits() and getRegUnit() but not in computeVirtRegs(), because I did not bring any performance benefits to computeVirtRegs() and for some examples even brought a slow down. Patch by Vaidas Gasiunas <vaidas.gasiunas@sap.com> Differential Revision: http://reviews.llvm.org/D6013 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228421 91177308-0d34-0410-b5e6-96231b3b80d8		2015-02-06 18:42:41 +00:00
..
Analysis	[LV] Move addRuntimeCheck to LoopAccessAnalysis	2015-02-06 18:31:04 +00:00
AsmParser	AsmParser: Split out LineField, NFC	2015-02-04 22:59:18 +00:00
Bitcode	IR: Initialize MDNode abbreviations en masse, NFC	2015-02-04 21:54:12 +00:00
CodeGen	[LiveIntervalAnalysis] Speed up creation of live ranges for physical registers	2015-02-06 18:42:41 +00:00
DebugInfo
ExecutionEngine	[MC] Remove various unused MCAsmInfo parameters.	2015-02-05 00:58:51 +00:00
Fuzzer	[fuzzer] add flag prefer_small_during_initial_shuffle, be a bit more verbose	2015-02-04 23:42:42 +00:00
IR	Teach isDereferenceablePointer() to look through bitcast constant expressions.	2015-02-05 09:15:37 +00:00
IRReader
LineEditor
Linker
LTO	[LTO API] split lto_codegen_compile to lto_codegen_optimize and	2015-02-03 18:39:15 +00:00
MC	Try to fix the build in MCValue.cpp	2015-02-05 01:23:14 +00:00
Object
Option
ProfileData	InstrProf: Use a stable sort when reading coverage regions	2015-02-04 00:12:18 +00:00
Support	Make helper functions/classes/globals static. NFC.	2015-02-06 17:51:54 +00:00
TableGen
Target	Don't dllexport declarations	2015-02-06 17:59:49 +00:00
Transforms	[LV] Move addRuntimeCheck to LoopAccessAnalysis	2015-02-06 18:31:04 +00:00
CMakeLists.txt
LLVMBuild.txt
Makefile