llvm-project

History

Erich Keane 892e633194 Fix r350643 to limit COFF emission to <= 32 BYTES instead of BITS. The patch in r350643 incorrectly sets the COFF emission based on bits instead of bytes. This patch converts the 32 via CharUnits to bits to compare the correct values. Change-Id: Icf38a16470ad5ae3531374969c033557ddb0d323 llvm-svn: 353411		2019-02-07 15:14:11 +00:00
..
ABIInfo.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
Address.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
BackendUtil.cpp	[NewPM][MSan] Add Options Handling	2019-02-04 21:02:49 +00:00
CGAtomic.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGBlocks.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGBlocks.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGBuilder.h	Minor cleanup: remove CGBuild::CreateConstByteGEP overloads taking a Value.	2019-02-05 19:01:33 +00:00
CGBuiltin.cpp	[COFF, ARM64] Add ARM64 support for MS intrinsic _fastfail	2019-02-06 20:08:26 +00:00
CGCUDANV.cpp	Basic CUDA-10 support.	2019-02-05 22:38:58 +00:00
CGCUDARuntime.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGCUDARuntime.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGCXX.cpp	[opaque pointer types] Pass through function types for TLS	2019-02-07 01:14:17 +00:00
CGCXXABI.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGCXXABI.h	[opaque pointer types] Pass through function types for TLS	2019-02-07 01:14:17 +00:00
CGCall.cpp	[opaque pointer types] Make EmitCall pass Function Types to	2019-02-07 01:15:41 +00:00
CGCall.h	[opaque pointer types] Make EmitCall pass Function Types to	2019-02-07 01:15:41 +00:00
CGClass.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGCleanup.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGCleanup.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGCoroutine.cpp	[opaque pointer types] Trivial changes towards CallInst requiring	2019-02-03 21:53:49 +00:00
CGDebugInfo.cpp	Fix a missing word in comment	2019-02-05 21:21:01 +00:00
CGDebugInfo.h	Reland r345009 "[DebugInfo] Generate debug information for labels."	2019-01-24 05:34:29 +00:00
CGDecl.cpp	[opaque pointer types] More trivial changes to pass FunctionType to CallInst.	2019-02-05 19:17:50 +00:00
CGDeclCXX.cpp	[opaque pointer types] Pass through function types for TLS	2019-02-07 01:14:17 +00:00
CGException.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGExpr.cpp	[opaque pointer types] Pass through function types for TLS	2019-02-07 01:14:17 +00:00
CGExprAgg.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGExprCXX.cpp	Fix MSVC constructor call extension after `b92d290e48` (r353181).	2019-02-06 00:06:03 +00:00
CGExprComplex.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGExprConstant.cpp	[CodeGen] Always use string computed in Sema for PredefinedExpr	2019-01-22 00:11:17 +00:00
CGExprScalar.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGGPUBuiltin.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGLoopInfo.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGLoopInfo.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGNonTrivialStruct.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGObjC.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGObjCGNU.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGObjCMac.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGObjCRuntime.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGObjCRuntime.h	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGOpenCLRuntime.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGOpenCLRuntime.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGOpenMPRuntime.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGOpenMPRuntime.h	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGOpenMPRuntimeNVPTX.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGOpenMPRuntimeNVPTX.h	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGRecordLayout.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGRecordLayoutBuilder.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGStmt.cpp	Cleanup: replace uses of CallSite with CallBase.	2019-01-30 02:54:28 +00:00
CGStmtOpenMP.cpp	[opaque pointer types] Pass function types for runtime function calls.	2019-02-05 16:42:33 +00:00
CGVTT.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGVTables.cpp	[opaque pointer types] More trivial changes to pass FunctionType to CallInst.	2019-02-05 19:17:50 +00:00
CGVTables.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CGValue.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CMakeLists.txt	[CodeGen] Fix -DBUILD_SHARED_LIBS=on build after rC348907	2018-12-12 06:07:33 +00:00
CodeGenABITypes.cpp	Remove redundant FunctionDecl argument from a couple functions.	2019-02-02 01:48:23 +00:00
CodeGenAction.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CodeGenFunction.cpp	[opaque pointer types] Trivial changes towards CallInst requiring	2019-02-03 21:53:49 +00:00
CodeGenFunction.h	[opaque pointer types] Pass through function types for TLS	2019-02-07 01:14:17 +00:00
CodeGenModule.cpp	Fix r350643 to limit COFF emission to <= 32 BYTES instead of BITS.	2019-02-07 15:14:11 +00:00
CodeGenModule.h	[opaque pointer types] Pass through function types for TLS	2019-02-07 01:14:17 +00:00
CodeGenPGO.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CodeGenPGO.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CodeGenTBAA.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CodeGenTBAA.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CodeGenTypeCache.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CodeGenTypes.cpp	Remove redundant FunctionDecl argument from a couple functions.	2019-02-02 01:48:23 +00:00
CodeGenTypes.h	[opaque pointer types] Fix the CallInfo passed to EmitCall in some	2019-02-05 16:05:50 +00:00
ConstantEmitter.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ConstantInitBuilder.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CoverageMappingGen.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CoverageMappingGen.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
EHScopeStack.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ItaniumCXXABI.cpp	[opaque pointer types] Pass through function types for TLS	2019-02-07 01:14:17 +00:00
MacroPPCallbacks.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MacroPPCallbacks.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MicrosoftCXXABI.cpp	[opaque pointer types] Pass through function types for TLS	2019-02-07 01:14:17 +00:00
ModuleBuilder.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ObjectFilePCHContainerOperations.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
README.txt	…
SanitizerMetadata.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SanitizerMetadata.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SwiftCallingConv.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
TargetInfo.cpp	Minor cleanup: remove CGBuild::CreateConstByteGEP overloads taking a Value.	2019-02-05 19:01:33 +00:00
TargetInfo.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
VarBypassDetector.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
VarBypassDetector.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +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!

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