llvm-project/clang/lib/CodeGen
Richard Smith 69d0d2626a New -fcatch-undefined-behavior features:
* when checking that a pointer or reference refers to appropriate storage for a type, also check the alignment and perform a null check
 * check that references are bound to appropriate storage
 * check that 'this' has appropriate storage in member accesses and member function calls

llvm-svn: 162523
2012-08-24 00:54:33 +00:00
..
ABIInfo.h Handle functions with struct arguments or return types and the regparm 2012-07-31 02:44:24 +00:00
BackendUtil.cpp [driver] Add support for the --param ssp-buffer-size= driver option. 2012-08-21 16:16:06 +00:00
CGBlocks.cpp Distinguish more carefully between free functions and C++ instance methods 2012-07-07 06:41:13 +00:00
CGBlocks.h Whenever explicitly activating or deactivating a cleanup, we 2011-11-10 10:43:54 +00:00
CGBuilder.h Update Clang to reflect the new home of IRBuilder.h as of r159421. 2012-06-29 12:39:08 +00:00
CGBuiltin.cpp Attempt to fix clang bootstrap (broken by r162425). 2012-08-23 11:27:56 +00:00
CGCUDANV.cpp CUDA: IR generation support for device stubs 2011-10-06 18:51:56 +00:00
CGCUDARuntime.cpp CUDA: IR generation support for kernel call expressions 2011-10-06 18:29:37 +00:00
CGCUDARuntime.h CUDA: IR generation support for device stubs 2011-10-06 18:51:56 +00:00
CGCXX.cpp Remove get(V)BaseClassOffsetInBits, the CharUnit functions should be used instead. 2012-07-04 18:45:14 +00:00
CGCXXABI.cpp Fix PR13234 - crash when trying to report an unsupported ABI feature 2012-06-29 01:14:21 +00:00
CGCXXABI.h [Windows] Abstract pure virtual method calls in the ABI. Fix the Windows ABI to forward to the correct function. 2012-07-17 17:10:11 +00:00
CGCall.cpp Handle functions with struct arguments or return types and the regparm 2012-07-31 02:44:24 +00:00
CGCall.h Whether an argument is required (in contrast with being an 2012-02-17 03:33:10 +00:00
CGClass.cpp Fix an assertion failure with a C++ constructor initializing a 2012-08-08 03:51:37 +00:00
CGCleanup.cpp Make sure we don't emit IR for unused EH cleanups. PR13359. 2012-08-02 00:10:24 +00:00
CGCleanup.h Documentation cleanup: 2012-06-15 22:10:14 +00:00
CGDebugInfo.cpp Reapply: 2012-08-20 23:32:17 +00:00
CGDebugInfo.h Reapply: 2012-08-20 23:32:17 +00:00
CGDecl.cpp Add -ftls-model command-line flag. 2012-06-28 08:01:44 +00:00
CGDeclCXX.cpp Emit debug info for dynamic initializers. Permit __attribute__((nodebug)) on 2012-07-24 01:40:49 +00:00
CGException.cpp Add the ObjFW runtime. Patch by Jonathan Schleifer! 2012-07-12 02:07:58 +00:00
CGExpr.cpp New -fcatch-undefined-behavior features: 2012-08-24 00:54:33 +00:00
CGExprAgg.cpp New -fcatch-undefined-behavior features: 2012-08-24 00:54:33 +00:00
CGExprCXX.cpp New -fcatch-undefined-behavior features: 2012-08-24 00:54:33 +00:00
CGExprComplex.cpp Unify naming of LangOptions variable/get function across the Clang stack (Lex to AST). 2012-03-11 07:00:24 +00:00
CGExprConstant.cpp Remove get(V)BaseClassOffsetInBits, the CharUnit functions should be used instead. 2012-07-04 18:45:14 +00:00
CGExprScalar.cpp New -fcatch-undefined-behavior features: 2012-08-24 00:54:33 +00:00
CGObjC.cpp Screw around with ObjCRuntime some more, changing the 2012-08-21 02:47:43 +00:00
CGObjCGNU.cpp Fix transposed optional / required in Objective-C metadata (GNUstep runtime) 2012-08-23 12:17:21 +00:00
CGObjCMac.cpp Remove deprecated getNameAsCString methods. 2012-07-31 11:45:39 +00:00
CGObjCRuntime.cpp Distinguish more carefully between free functions and C++ instance methods 2012-07-07 06:41:13 +00:00
CGObjCRuntime.h Documentation cleanup: 2012-06-15 22:10:14 +00:00
CGOpenCLRuntime.cpp OpenCL: introduce support for function scope __local variables 2011-09-19 21:14:35 +00:00
CGOpenCLRuntime.h OpenCL: introduce support for function scope __local variables 2011-09-19 21:14:35 +00:00
CGRTTI.cpp Fix a few -Wdocumentation warnings. 2012-08-24 00:01:24 +00:00
CGRecordLayout.h Propagate lvalue alignment into bitfields. Per report on cfe-dev. 2012-06-27 21:19:48 +00:00
CGRecordLayoutBuilder.cpp Propagate lvalue alignment into bitfields. Per report on cfe-dev. 2012-06-27 21:19:48 +00:00
CGStmt.cpp [ms-inline asm] Remove an unused argument. This logic can now be reused by the 2012-08-23 20:00:18 +00:00
CGVTT.cpp simplify a bunch of code to use the well-known LLVM IR types computed by CodeGenModule. 2012-02-07 00:39:47 +00:00
CGVTables.cpp Don't crash *or* insert a bogus autorelease when emitting a 2012-07-31 00:33:55 +00:00
CGVTables.h Move VTable builder to AST 2011-09-26 01:57:12 +00:00
CGValue.h Fix for PR#13606: http://llvm.org/bugs/show_bug.cgi?id=13606 2012-08-15 18:40:30 +00:00
CMakeLists.txt clang/lib: [CMake] Update tblgen'd dependencies. 2012-07-27 06:18:33 +00:00
CodeGenAction.cpp Escape % in diagnostic message when compiling LLVM IR. 2012-03-16 22:31:42 +00:00
CodeGenFunction.cpp Change APInt to APSInt in one instance. Also change a call to operator==() to 2012-07-23 20:21:35 +00:00
CodeGenFunction.h New -fcatch-undefined-behavior features: 2012-08-24 00:54:33 +00:00
CodeGenModule.cpp Reduce duplicated hash map lookups. 2012-08-22 15:37:55 +00:00
CodeGenModule.h Add -ftls-model command-line flag. 2012-06-28 08:01:44 +00:00
CodeGenTBAA.cpp Remove unused private member variables found by clang's new -Wunused-private-field. 2012-06-06 17:32:50 +00:00
CodeGenTBAA.h Update Clang to reflect the move of MDBuilder in r160237. 2012-07-15 23:28:01 +00:00
CodeGenTypes.cpp Distinguish more carefully between free functions and C++ instance methods 2012-07-07 06:41:13 +00:00
CodeGenTypes.h Distinguish more carefully between free functions and C++ instance methods 2012-07-07 06:41:13 +00:00
ItaniumCXXABI.cpp [Windows] Abstract pure virtual method calls in the ABI. Fix the Windows ABI to forward to the correct function. 2012-07-17 17:10:11 +00:00
Makefile BUILD_ARCHIVE is the default for libraries, no need to set it. 2010-07-18 00:14:47 +00:00
MicrosoftCXXABI.cpp [Windows] Abstract pure virtual method calls in the ABI. Fix the Windows ABI to forward to the correct function. 2012-07-17 17:10:11 +00:00
ModuleBuilder.cpp Unify naming of LangOptions variable/get function across the Clang stack (Lex to AST). 2012-03-11 07:00:24 +00:00
README.txt
TargetInfo.cpp ARM: enable struct byval for AAPCS-VFP. 2012-08-13 21:23:55 +00:00
TargetInfo.h Whether an argument is required (in contrast with being an 2012-02-17 03:33:10 +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!

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