test/CodeGenCXX · a530e823ed2793ac149de7a984014e242a787682 · HPC2SE-Project / pacxx-clang

[ubsan] Skip alignment checks on allocas with known alignment

Vedant Kumar authored 7 years ago

It's possible to determine the alignment of an alloca at compile-time.
Use this information to skip emitting some runtime alignment checks.

Testing: check-clang, check-ubsan.

This significantly reduces the amount of alignment checks we emit when
compiling X86ISelLowering.cpp. Here are the numbers from patched/unpatched
clangs based on r301361.

  ------------------------------------------
  | Setup          | # of alignment checks |
  ------------------------------------------
  | unpatched, -O0 |                 47195 |
  | patched, -O0   |                 30876 | (-34.6%)
  ------------------------------------------

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@301377 91177308-0d34-0410-b5e6-96231b3b80d8

fb77f039

History

fb77f039 7 years ago

History

Name	Last commit	Last update
..
Inputs
2003-11-02-WeakLinkage.cpp
2003-11-18-PtrMemConstantInitializer.cpp
2003-11-27-MultipleInheritanceThunk.cpp
2003-11-29-DuplicatedCleanupTest.cpp
2003-12-08-ArrayOfPtrToMemberFunc.cpp
2004-01-11-DynamicInitializedConstant.cpp
2004-03-08-ReinterpretCastCopy.cpp
2004-03-09-UnmangledBuiltinMethods.cpp
2004-03-15-CleanupsAndGotos.cpp
2004-06-08-LateTemplateInstantiation.cpp
2004-09-27-DidntEmitTemplate.cpp
2004-11-27-ExceptionCleanupAssertion.cpp
2004-11-27-FriendDefaultArgCrash.cpp
2005-01-03-StaticInitializers.cpp
2005-02-11-AnonymousUnion.cpp
2005-02-13-BadDynamicInit.cpp
2005-02-19-BitfieldStructCrash.cpp
2005-02-19-UnnamedVirtualThunkArgument.cpp
2005-02-20-BrokenReferenceTest.cpp
2006-03-01-GimplifyCrash.cpp
2006-03-06-C++RecurseCrash.cpp
2006-09-12-OpaqueStructCrash.cpp
2006-10-30-ClassBitfield.cpp
2006-11-20-GlobalSymbols.cpp
2006-11-30-ConstantExprCrash.cpp
2007-01-02-UnboundedArray.cpp
2007-01-06-PtrMethodInit.cpp
2007-04-05-PackedBitFields-1.cpp
2007-04-05-PackedBitFieldsOverlap-2.cpp
2007-04-05-PackedBitFieldsOverlap.cpp
2007-04-05-PackedBitFieldsSmall.cpp
2007-04-05-StructPackedFieldUnpacked.cpp
2007-04-10-PackedUnion.cpp
2007-04-14-FNoBuiltin.cpp
2007-05-03-VectorInit.cpp
2007-07-29-RestrictPtrArg.cpp
2007-07-29-RestrictRefArg.cpp
2007-09-10-RecursiveTypeResolution.cpp
2007-10-01-StructResize.cpp
2008-01-12-VecInit.cpp
2008-05-07-CrazyOffsetOf.cpp
2009-03-17-dbg.cpp
2009-04-23-bool2.cpp
2009-05-04-PureConstNounwind.cpp
2009-06-16-DebugInfoCrash.cpp
2009-07-16-Using.cpp
2009-08-05-ZeroInitWidth.cpp
2009-08-11-VectorRetTy.cpp
2009-09-09-packed-layout.cpp
2009-10-27-crash.cpp
2009-12-23-MissingSext.cpp
2010-03-09-AnonAggregate.cpp
2010-05-10-Var-DbgInfo.cpp
2010-05-11-alwaysinlineinstantiation.cpp
2010-05-12-PtrToMember-Dbg.cpp
2010-06-21-LocalVarDbg.cpp
2010-06-22-BitfieldInit.cpp
2010-06-22-ZeroBitfield.cpp
2010-07-23-DeclLoc.cpp
2011-12-19-init-list-ctor.cpp
2012-02-06-VecInitialization.cpp
2012-03-16-StoreAlign.cpp
DynArrayInit.cpp
PR19955.cpp
PR20038.cpp
PR24289.cpp
PR26569.cpp
PR28220.cpp
PR28523.cpp
PR4827-cast.cpp
PR4983-constructor-conversion.cpp
PR5050-constructor-conversion.cpp
PR5093-static-member-function.cpp
PR5834-constructor-conversion.cpp
PR5863-unreachable-block.cpp
PR6474.cpp
__null.cpp
aarch64-aapcs-zerolength-bitfield.cpp
aarch64-arguments.cpp
aarch64-cxxabi.cpp
aarch64-mangle-neon-vectors.cpp
aarch64-neon.cpp
abstract-class-ctors-dtors.cpp
address-of-fntemplate.cpp
address-space-ref.cpp
alias-available-externally.cpp
align-avx-complete-objects.cpp
alignment.cpp
alloc-size.cpp
alloca-align.cpp
anonymous-namespaces.cpp
anonymous-union-member-initializer.cpp
apple-kext-guard-variable.cpp
apple-kext-indirect-call-2.cpp
apple-kext-indirect-call.cpp
apple-kext-indirect-virtual-dtor-call.cpp
apple-kext-linkage.cpp
apple-kext-no-staticinit-section.cpp
apple-kext.cpp