llvm-project/clang/lib/CodeGen
Justin Lebar 5a7df9c130 Call TargetMachine::addEarlyAsPossiblePasses from BackendUtil.
Summary:
As of D18614, TargetMachine exposes a hook to add a set of passes that should
be run as early as possible.  Invoke this hook from clang when setting up the
pass manager.

Reviewers: chandlerc

Subscribers: rnk, cfe-commits, tra

Differential Revision: http://reviews.llvm.org/D18617

llvm-svn: 267764
2016-04-27 19:12:56 +00:00
..
ABIInfo.h IRGen-level lowering for the Swift calling convention. 2016-04-04 18:33:08 +00:00
Address.h Work around build failure due to GCC 4.8.1 bug. We don't completely understand 2016-02-02 23:11:49 +00:00
BackendUtil.cpp Call TargetMachine::addEarlyAsPossiblePasses from BackendUtil. 2016-04-27 19:12:56 +00:00
CGAtomic.cpp NFC: unify clang / LLVM atomic ordering 2016-04-18 18:01:49 +00:00
CGBlocks.cpp Preserve ExtParameterInfos into CGFunctionInfo. 2016-03-11 04:30:31 +00:00
CGBlocks.h Move BlockByrefHelpers back to CodeGenModule.h to placate MSVC. 2015-09-08 08:21:11 +00:00
CGBuilder.h Remove compile time PreserveName in favor of a runtime cc1 -discard-value-names option 2016-03-13 21:05:23 +00:00
CGBuiltin.cpp [AArch64] Fix D19098 fallout. 2016-04-19 20:51:00 +00:00
CGCUDABuiltin.cpp [CUDA] Don't crash when trying to printf a non-scalar object. 2016-02-11 02:00:52 +00:00
CGCUDANV.cpp [CUDA] Do not generate unnecessary runtime init code. 2016-03-02 18:28:53 +00:00
CGCUDARuntime.cpp Roll-back r250822. 2015-10-20 13:23:58 +00:00
CGCUDARuntime.h [CUDA] Emit host-side 'shadows' for device-side global variables 2016-03-02 18:28:50 +00:00
CGCXX.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CGCXXABI.cpp Add the `pass_object_size` attribute to clang. 2015-12-02 21:58:08 +00:00
CGCXXABI.h Fix use-after-free when a C++ thread_local variable gets replaced (because its 2015-12-01 01:10:48 +00:00
CGCall.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CGCall.h Don't emit exceptional stackrestore cleanups around inalloca functions 2015-10-08 00:17:45 +00:00
CGClass.cpp [modules] Remove CXX_CTOR_INITIALIZERS_OFFSETS table. Instead of storing an ID 2016-04-13 21:57:08 +00:00
CGCleanup.cpp [CodeGen] Emit lifetime.end intrinsic after objects are destructed in 2016-04-01 22:58:55 +00:00
CGCleanup.h Update for LLVM function name change. 2016-01-14 21:00:27 +00:00
CGDebugInfo.cpp PR21823: 'nodebug' attribute on global/static variables. 2016-04-27 17:37:12 +00:00
CGDebugInfo.h [OpenCL] Move OpenCLImageTypes.def from clangAST to clangBasic library. 2016-04-13 08:33:41 +00:00
CGDecl.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CGDeclCXX.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CGException.cpp [SEH] Remove nounwind/noinline from outlined finally funclets 2016-03-11 17:36:16 +00:00
CGExpr.cpp Remove redundant conditions of the form (A || (!A && B)) -> (A || B) 2016-04-11 08:26:13 +00:00
CGExprAgg.cpp Fix -Werror build. 2016-03-08 23:16:16 +00:00
CGExprCXX.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CGExprComplex.cpp [Bugfix] Fix ICE on constexpr vector splat. 2016-01-13 01:52:39 +00:00
CGExprConstant.cpp P0017R1: In C++1z, an aggregate class can have (public non-virtual) base classes; these are initialized as if they were data members. 2016-03-08 22:17:41 +00:00
CGExprScalar.cpp Revert 266186 as it breaks anything that includes type_traits on some platforms 2016-04-15 18:04:13 +00:00
CGLoopInfo.cpp CGLoopInfo: Use the MD_loop metadata kind from r264371, NFC 2016-03-25 00:38:14 +00:00
CGLoopInfo.h Add new llvm.loop.unroll.enable metadata for use with "#pragma unroll". 2015-08-10 17:29:39 +00:00
CGObjC.cpp [ObjC] Pop all cleanups created in EmitObjCForCollectionStmt before 2016-04-12 23:10:58 +00:00
CGObjCGNU.cpp Reduce the number of implicit StringRef->std::string conversions by threading StringRef through more APIs. 2016-02-13 13:42:54 +00:00
CGObjCMac.cpp ObjC Class Property: don't emit class properties on old deployment targets. 2016-04-19 19:05:03 +00:00
CGObjCRuntime.cpp Preserve ExtParameterInfos into CGFunctionInfo. 2016-03-11 04:30:31 +00:00
CGObjCRuntime.h Reduce the number of implicit StringRef->std::string conversions by threading StringRef through more APIs. 2016-02-13 13:42:54 +00:00
CGOpenCLRuntime.cpp [OpenCL] Move OpenCLImageTypes.def from clangAST to clangBasic library. 2016-04-13 08:33:41 +00:00
CGOpenCLRuntime.h [OpenCL] Pipe type support 2016-01-09 12:53:17 +00:00
CGOpenMPRuntime.cpp [OPENMP] Fix for codegen of captured variables in inlined directives. 2016-04-27 07:56:03 +00:00
CGOpenMPRuntime.h CGOpenMPRuntime.h: Prune '\param IfCond' in r267395. [-Wdocumentation] 2016-04-26 00:45:00 +00:00
CGOpenMPRuntimeNVPTX.cpp [OPENMP] Codegen for teams directive for NVPTX 2016-04-04 15:55:02 +00:00
CGOpenMPRuntimeNVPTX.h [OPENMP] Codegen for teams directive for NVPTX 2016-04-04 15:55:02 +00:00
CGRecordLayout.h Make CodeGen headers self-contained. 2016-02-02 16:05:18 +00:00
CGRecordLayoutBuilder.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CGStmt.cpp reduce indentation; NFCI 2016-04-19 17:13:14 +00:00
CGStmtOpenMP.cpp [OPENMP] Fix crash on initialization of classes with no init clause in 2016-04-27 11:38:05 +00:00
CGVTT.cpp CodeGen: Use 32-bit gep offsets to address vtable address points. 2016-03-14 19:07:10 +00:00
CGVTables.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CGVTables.h [CodeGen] Remove dead code. NFC. 2015-10-15 15:29:40 +00:00
CGValue.h [Sema] PR26444 fix crash when alignment value is >= 2**16 2016-03-02 06:48:47 +00:00
CMakeLists.txt IRGen-level lowering for the Swift calling convention. 2016-04-04 18:33:08 +00:00
CodeGenABITypes.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CodeGenAction.cpp Enable ODR uniquing of DITypes for ThinLTO backends 2016-04-20 02:23:52 +00:00
CodeGenFunction.cpp reduce indentation; NFCI 2016-04-19 18:06:33 +00:00
CodeGenFunction.h [OPENMP] Fix for codegen of captured variables in inlined directives. 2016-04-27 07:56:03 +00:00
CodeGenModule.cpp [CodeGen] Avoid ctor/dtor boilerplate with some C++11 2016-04-13 23:37:17 +00:00
CodeGenModule.h [CodeGen] Avoid ctor/dtor boilerplate with some C++11 2016-04-13 23:37:17 +00:00
CodeGenPGO.cpp PGO] PGOFuncName meta data if PGOFuncName is different from function's raw name 2016-04-22 21:19:05 +00:00
CodeGenPGO.h revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CodeGenTBAA.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
CodeGenTBAA.h Make the remaining headers self-contained. 2016-02-02 14:24:21 +00:00
CodeGenTypeCache.h Compute and preserve alignment more faithfully in IR-generation. 2015-09-08 08:05:57 +00:00
CodeGenTypes.cpp Revert 266186 as it breaks anything that includes type_traits on some platforms 2016-04-15 18:04:13 +00:00
CodeGenTypes.h IRGen-level lowering for the Swift calling convention. 2016-04-04 18:33:08 +00:00
CoverageMappingGen.cpp [Coverage] Fix the start/end locations of switch statements 2016-03-04 08:07:15 +00:00
CoverageMappingGen.h revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
EHScopeStack.h [CodeGen] Emit lifetime.end intrinsic after objects are destructed in 2016-04-01 22:58:55 +00:00
ItaniumCXXABI.cpp Revert 266186 as it breaks anything that includes type_traits on some platforms 2016-04-15 18:04:13 +00:00
MicrosoftCXXABI.cpp Silencing warnings from MSVC 2015 Update 2. Both of these changes silence "C4334 '<<': result of 32-bit shift implicitly converted to 64 bits (was 64-bit shift intended?)". NFC. 2016-03-30 21:33:34 +00:00
ModuleBuilder.cpp Fix a bug involving deferred decl emission and PCH 2016-04-22 18:46:33 +00:00
ObjectFilePCHContainerOperations.cpp revert SVN r265702, r265640 2016-04-08 16:52:00 +00:00
README.txt
SanitizerMetadata.cpp [ASan] Initial support for Kernel AddressSanitizer 2015-06-19 12:19:07 +00:00
SanitizerMetadata.h Removing LLVM_DELETED_FUNCTION, as MSVC 2012 was the last reason for requiring the macro. NFC; Clang edition. 2015-02-15 22:54:08 +00:00
SwiftCallingConv.cpp Silencing a 32-bit shift implicit conversion warning from MSVC; NFC. 2016-04-08 12:21:58 +00:00
TargetInfo.cpp [SPIR] Remove an assert mandating SPIR for OpenCL sources only. 2016-04-26 15:14:01 +00:00
TargetInfo.h IRGen-level lowering for the Swift calling convention. 2016-04-04 18:33:08 +00:00

README.txt

IRgen optimization opportunities.

//===---------------------------------------------------------------------===//

The common pattern of
--
short x; // or char, etc
(x == 10)
--
generates an zext/sext of x which can easily be avoided.

//===---------------------------------------------------------------------===//

Bitfields accesses can be shifted to simplify masking and sign
extension. For example, if the bitfield width is 8 and it is
appropriately aligned then is is a lot shorter to just load the char
directly.

//===---------------------------------------------------------------------===//

It may be worth avoiding creation of alloca's for formal arguments
for the common situation where the argument is never written to or has
its address taken. The idea would be to begin generating code by using
the argument directly and if its address is taken or it is stored to
then generate the alloca and patch up the existing code.

In theory, the same optimization could be a win for block local
variables as long as the declaration dominates all statements in the
block.

NOTE: The main case we care about this for is for -O0 -g compile time
performance, and in that scenario we will need to emit the alloca
anyway currently to emit proper debug info. So this is blocked by
being able to emit debug information which refers to an LLVM
temporary, not an alloca.

//===---------------------------------------------------------------------===//

We should try and avoid generating basic blocks which only contain
jumps. At -O0, this penalizes us all the way from IRgen (malloc &
instruction overhead), all the way down through code generation and
assembly time.

On 176.gcc:expr.ll, it looks like over 12% of basic blocks are just
direct branches!

//===---------------------------------------------------------------------===//