llvm-project/clang/lib/CodeGen
Reid Kleckner 4982b82b73 [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32
This fixes PR15768, where the sret parameter and the 'this' parameter
are in the wrong order.

Instance methods compiled by MSVC never return records in registers,
they always return indirectly through an sret pointer.  That sret
pointer always comes after the 'this' parameter, for both __cdecl and
__thiscall methods.

Unfortunately, the same is true for other calling conventions, so we'll
have to change the overall approach here relatively soon.

Reviewers: rsmith

Differential Revision: http://llvm-reviews.chandlerc.com/D2664

llvm-svn: 200587
2014-01-31 22:54:50 +00:00
..
ABIInfo.h Sort all the #include lines with LLVM's utils/sort_includes.py which 2014-01-07 11:51:46 +00:00
BackendUtil.cpp [asan] Remove -fsanitize-address-zero-base-shadow command line 2014-01-16 10:19:31 +00:00
CGAtomic.cpp Add CodeGenABITypes.h for use in LLDB. 2013-10-30 21:53:58 +00:00
CGBlocks.cpp [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
CGBlocks.h Remove useless 'llvm::' qualifier from names like StringRef and others that are 2013-01-12 19:30:44 +00:00
CGBuilder.h Rewrite #includes for llvm/Foo.h to llvm/IR/Foo.h as appropriate to 2013-01-02 11:45:17 +00:00
CGBuiltin.cpp ARM & AArch64: unify the rest of the completely shared NEON implementations 2014-01-31 10:46:52 +00:00
CGCUDANV.cpp Use the actual ABI-determined C calling convention for runtime 2013-02-28 19:01:20 +00:00
CGCUDARuntime.cpp CodeGen: Initial instrumentation based PGO implementation 2014-01-06 22:27:43 +00:00
CGCUDARuntime.h CUDA: IR generation support for device stubs 2011-10-06 18:51:56 +00:00
CGCXX.cpp [ms-abi] Always generate complete constructors in the Microsoft C++ ABI 2014-01-13 22:57:31 +00:00
CGCXXABI.cpp [ms-cxxabi] The 'most derived' ctor parameter usually comes last 2013-12-17 19:46:40 +00:00
CGCXXABI.h [ms-cxxabi] The 'most derived' ctor parameter usually comes last 2013-12-17 19:46:40 +00:00
CGCall.cpp [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
CGCall.h Add CodeGenABITypes.h for use in LLDB. 2013-10-30 21:53:58 +00:00
CGClass.cpp Rename getResultType() on function and method declarations to getReturnType() 2014-01-25 16:55:45 +00:00
CGCleanup.cpp Revert "CodeGen: Simplify CodeGenFunction::EmitCaseStmt" 2014-01-21 00:35:11 +00:00
CGCleanup.h Fix leak in lib/CodeGen/CGException.cpp, PR18318 2014-01-09 09:22:32 +00:00
CGDebugInfo.cpp Rename getResultType() on function and method declarations to getReturnType() 2014-01-25 16:55:45 +00:00
CGDebugInfo.h Debug info: Refactor NoLocation and ArtificialLocation to use a common base 2014-01-17 00:15:10 +00:00
CGDecl.cpp Fix a tranche of comment, test and doc typos 2013-12-05 16:25:25 +00:00
CGDeclCXX.cpp [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
CGException.cpp Debug info: Refactor NoLocation and ArtificialLocation to use a common base 2014-01-17 00:15:10 +00:00
CGExpr.cpp Rename getResultType() on function and method declarations to getReturnType() 2014-01-25 16:55:45 +00:00
CGExprAgg.cpp Handle va_arg on struct types for the le32 target (PNaCl and Emscripten) 2014-01-22 20:11:01 +00:00
CGExprCXX.cpp Rename getResultType() on function and method declarations to getReturnType() 2014-01-25 16:55:45 +00:00
CGExprComplex.cpp CodeGen: Rename adjustFallThroughCount -> adjustForControlFlow 2014-01-13 21:24:22 +00:00
CGExprConstant.cpp Rename isBuiltinCall() to getBuiltinCallee() 2013-12-28 21:59:02 +00:00
CGExprScalar.cpp Rename getResultType() on function and method declarations to getReturnType() 2014-01-25 16:55:45 +00:00
CGObjC.cpp [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
CGObjCGNU.cpp Use getPointerSizeInBits. 2014-01-09 21:32:51 +00:00
CGObjCMac.cpp [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
CGObjCRuntime.cpp Add CodeGenABITypes.h for use in LLDB. 2013-10-30 21:53:58 +00:00
CGObjCRuntime.h Use the actual ABI-determined C calling convention for runtime 2013-02-28 19:01:20 +00:00
CGOpenCLRuntime.cpp The OpenCL specification states that images are allocated 2014-01-09 13:37:30 +00:00
CGOpenCLRuntime.h Rewrite #includes for llvm/Foo.h to llvm/IR/Foo.h as appropriate to 2013-01-02 11:45:17 +00:00
CGRTTI.cpp Fix vbtable indices when a class shares the vbptr with a non-virtual base 2013-11-05 15:54:58 +00:00
CGRecordLayout.h Correct hyphenations in comments and assert messages 2013-12-05 04:47:09 +00:00
CGRecordLayoutBuilder.cpp Fixing PR18430 by checking that the size of bitfields plus padding does not 2014-01-29 00:09:16 +00:00
CGStmt.cpp [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
CGVTT.cpp Eliminate the ItaniumVTableContext object from CodeGenVTables 2013-12-20 23:58:52 +00:00
CGVTables.cpp Rename getResultType() on function and method declarations to getReturnType() 2014-01-25 16:55:45 +00:00
CGVTables.h Eliminate the ItaniumVTableContext object from CodeGenVTables 2013-12-20 23:58:52 +00:00
CGValue.h Simplify atomic load/store IRGen. 2013-07-11 01:32:21 +00:00
CMakeLists.txt Properly sort CMake list. NFC. 2014-01-06 23:20:52 +00:00
CodeGenABITypes.cpp [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
CodeGenAction.cpp Update for getLazyBitcodeModule API change. 2014-01-13 18:31:09 +00:00
CodeGenFunction.cpp Rename getResultType() on function and method declarations to getReturnType() 2014-01-25 16:55:45 +00:00
CodeGenFunction.h ARM & AArch64: move shared vld/vst intrinsics to common implementation. 2014-01-31 10:46:45 +00:00
CodeGenModule.cpp Enforce safe usage of DiagnosticsEngine::getCustomDiagID() 2014-01-26 06:17:37 +00:00
CodeGenModule.h CodeGen: Initial instrumentation based PGO implementation 2014-01-06 22:27:43 +00:00
CodeGenPGO.cpp Enforce safe usage of DiagnosticsEngine::getCustomDiagID() 2014-01-26 06:17:37 +00:00
CodeGenPGO.h CodeGen: Rename adjustFallThroughCount -> adjustForControlFlow 2014-01-13 21:24:22 +00:00
CodeGenTBAA.cpp Add a mangler entry point for TBAA rather than using RTTI directly 2013-11-19 23:23:00 +00:00
CodeGenTBAA.h Fixed comment typo. 2013-06-08 00:27:19 +00:00
CodeGenTypes.cpp Rename getResultType() on function and method declarations to getReturnType() 2014-01-25 16:55:45 +00:00
CodeGenTypes.h [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
EHScopeStack.h Sort all the #include lines with LLVM's utils/sort_includes.py which 2014-01-07 11:51:46 +00:00
ItaniumCXXABI.cpp [ms-cxxabi] The 'most derived' ctor parameter usually comes last 2013-12-17 19:46:40 +00:00
Makefile
MicrosoftCXXABI.cpp Revert "Revert r199416, "MS ABI: Improve selection of an inheritance model"" 2014-01-17 09:01:00 +00:00
ModuleBuilder.cpp Sort all the #include lines with LLVM's utils/sort_includes.py which 2014-01-07 11:51:46 +00:00
README.txt
TargetInfo.cpp [ms-cxxabi] Use x86_cdeclmethodcc for __cdecl methods on win32 2014-01-31 22:54:50 +00:00
TargetInfo.h Sort all the #include lines with LLVM's utils/sort_includes.py which 2014-01-07 11:51:46 +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!

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