forked from OSchip/llvm-project
fe96e0b6be
property references to use a new PseudoObjectExpr expression which pairs a syntactic form of the expression with a set of semantic expressions implementing it. This should significantly reduce the complexity required elsewhere in the compiler to deal with these kinds of expressions (e.g. IR generation's special l-value kind, the static analyzer's Message abstraction), at the lower cost of specifically dealing with the odd AST structure of these expressions. It should also greatly simplify efforts to implement similar language features in the future, most notably Managed C++'s properties and indexed properties. Most of the effort here is in dealing with the various clients of the AST. I've gone ahead and simplified the ObjC rewriter's use of properties; other clients, like IR-gen and the static analyzer, have all the old complexity *and* all the new complexity, at least temporarily. Many thanks to Ted for writing and advising on the necessary changes to the static analyzer. I've xfailed a small diagnostics regression in the static analyzer at Ted's request. llvm-svn: 143867 |
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.. | ||
ABIInfo.h | ||
BackendUtil.cpp | ||
CGBlocks.cpp | ||
CGBlocks.h | ||
CGBuilder.h | ||
CGBuiltin.cpp | ||
CGCUDANV.cpp | ||
CGCUDARuntime.cpp | ||
CGCUDARuntime.h | ||
CGCXX.cpp | ||
CGCXXABI.cpp | ||
CGCXXABI.h | ||
CGCall.cpp | ||
CGCall.h | ||
CGClass.cpp | ||
CGCleanup.cpp | ||
CGCleanup.h | ||
CGDebugInfo.cpp | ||
CGDebugInfo.h | ||
CGDecl.cpp | ||
CGDeclCXX.cpp | ||
CGException.cpp | ||
CGException.h | ||
CGExpr.cpp | ||
CGExprAgg.cpp | ||
CGExprCXX.cpp | ||
CGExprComplex.cpp | ||
CGExprConstant.cpp | ||
CGExprScalar.cpp | ||
CGObjC.cpp | ||
CGObjCGNU.cpp | ||
CGObjCMac.cpp | ||
CGObjCRuntime.cpp | ||
CGObjCRuntime.h | ||
CGOpenCLRuntime.cpp | ||
CGOpenCLRuntime.h | ||
CGRTTI.cpp | ||
CGRecordLayout.h | ||
CGRecordLayoutBuilder.cpp | ||
CGStmt.cpp | ||
CGTemporaries.cpp | ||
CGVTT.cpp | ||
CGVTables.cpp | ||
CGVTables.h | ||
CGValue.h | ||
CMakeLists.txt | ||
CodeGenAction.cpp | ||
CodeGenFunction.cpp | ||
CodeGenFunction.h | ||
CodeGenModule.cpp | ||
CodeGenModule.h | ||
CodeGenTBAA.cpp | ||
CodeGenTBAA.h | ||
CodeGenTypes.cpp | ||
CodeGenTypes.h | ||
ItaniumCXXABI.cpp | ||
Makefile | ||
MicrosoftCXXABI.cpp | ||
ModuleBuilder.cpp | ||
README.txt | ||
TargetInfo.cpp | ||
TargetInfo.h |
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! //===---------------------------------------------------------------------===//