llvm-6502/lib
Tobias Edler von Koch 3659b8adc9 Analyze recursive PHI nodes in BasicAA
Summary:
This patch allows phi nodes like
  %x = phi [ %incptr, ... ] [ %var, ... ]
  %incptr = getelementptr %x, 1
to be analyzed by BasicAliasAnalysis.

In aliasPHI, we can detect incoming values that are recursive GEPs with a
constant offset. Instead of trying to analyze a recursive GEP (and failing), 
we now ignore it and instead set the size of the memory referenced by
the PHINode to UnknownSize. This represents all the possible memory
locations the pointer represented by the PHINode could be advanced to
by the GEP.

For now, this new behavior is turned off by default to allow debugging of
performance degradations seen with SPEC/x86 and Hexagon benchmarks.
The flag -basicaa-recphi turns it on.


Reviewers: hfinkel, sanjoy

Subscribers: tobiasvk_caf, sanjoy, llvm-commits

Differential Revision: http://reviews.llvm.org/D10368

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242320 91177308-0d34-0410-b5e6-96231b3b80d8
2015-07-15 19:32:22 +00:00
..
Analysis Analyze recursive PHI nodes in BasicAA 2015-07-15 19:32:22 +00:00
AsmParser Add argmemonly attribute. 2015-07-11 10:30:36 +00:00
Bitcode Add argmemonly attribute. 2015-07-11 10:30:36 +00:00
CodeGen Revert "Refactor optimizeUncoalescable logic" 2015-07-15 18:10:46 +00:00
DebugInfo Return ErrorOr from getSymbolAddress. 2015-07-03 18:19:00 +00:00
ExecutionEngine Fix the -DBUILD_SHARED_LIBS=ON build. 2015-07-07 17:48:00 +00:00
Fuzzer [lib/Fuzzer] make assertions more informative and update comments for the user-supplied mutator 2015-05-30 17:33:13 +00:00
IR Debug Info: Add basic support for external types references. 2015-07-15 17:01:41 +00:00
IRReader Return a unique_ptr from getLazyBitcodeModule and parseBitcodeFile. NFC. 2015-06-16 22:27:55 +00:00
LibDriver Initial support for writing thin archives. 2015-07-15 05:47:46 +00:00
LineEditor
Linker Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
LTO LTO: expose LTO_SYMBOL_ALIAS, which indicates that the symbol is an alias. 2015-07-04 03:42:35 +00:00
MC [MC] Correctly escape .safeseh's symbol 2015-07-13 18:51:15 +00:00
Object Initial support for writing thin archives. 2015-07-15 05:47:46 +00:00
Option [Option] Plug a leak when move-assigning an InputArgList. 2015-06-23 15:28:10 +00:00
Passes
ProfileData Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC) 2015-06-23 09:49:53 +00:00
Support -Added API for retrieving the default FPU of a CPU from TargetParser. 2015-07-15 10:46:21 +00:00
TableGen [TableGen] Change a couple methods to return an ArrayRef instead of a const std::vector reference. NFC 2015-07-06 06:23:01 +00:00
Target Revert "Look through PHIs to find additional register sources" 2015-07-15 18:10:35 +00:00
Transforms [LoopUnrolling] Handle cast instructions. 2015-07-15 00:19:51 +00:00
CMakeLists.txt LibDriver, llvm-lib: introduce. 2015-06-09 21:50:22 +00:00
LLVMBuild.txt Wrap some long lines in LLVMBuild files. NFC 2015-06-12 18:44:57 +00:00
Makefile LibDriver, llvm-lib: introduce. 2015-06-09 21:50:22 +00:00