forked from OSchip/llvm-project
d6e6bf1808
APInt::slt was copying the LHS and RHS in to temporaries then making them unsigned so that it could use an unsigned comparision. It did this even on the paths which were trivial to give results for, such as the sign bit of the LHS being set while RHS was not set. This changes the logic to return out immediately in the trivial cases, and use an unsigned comparison in the remaining cases. But this time, just use the unsigned comparison directly without creating any temporaries. This works because, for example: true = (-2 slt -1) = (0xFE ult 0xFF) Also added some tests explicitly for slt with APInt's larger than 64-bits so that this new code is tested. Using the memory for 'opt -O2 verify-uselistorder.lto.opt.bc -o opt.bc' (see r236629 for details), this reduces the number of allocations from 26.8M to 23.9M. llvm-svn: 270881 |
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.. | ||
Unix | ||
Windows | ||
APFloat.cpp | ||
APInt.cpp | ||
APSInt.cpp | ||
ARMBuildAttrs.cpp | ||
ARMWinEH.cpp | ||
Allocator.cpp | ||
Atomic.cpp | ||
BlockFrequency.cpp | ||
BranchProbability.cpp | ||
CMakeLists.txt | ||
COM.cpp | ||
COPYRIGHT.regex | ||
CachePruning.cpp | ||
CommandLine.cpp | ||
Compression.cpp | ||
ConvertUTF.c | ||
ConvertUTFWrapper.cpp | ||
CrashRecoveryContext.cpp | ||
DAGDeltaAlgorithm.cpp | ||
DataExtractor.cpp | ||
DataStream.cpp | ||
Debug.cpp | ||
DeltaAlgorithm.cpp | ||
Dwarf.cpp | ||
DynamicLibrary.cpp | ||
Errno.cpp | ||
Error.cpp | ||
ErrorHandling.cpp | ||
FileOutputBuffer.cpp | ||
FileUtilities.cpp | ||
FoldingSet.cpp | ||
FormattedStream.cpp | ||
GraphWriter.cpp | ||
Hashing.cpp | ||
Host.cpp | ||
IntEqClasses.cpp | ||
IntervalMap.cpp | ||
IntrusiveRefCntPtr.cpp | ||
JamCRC.cpp | ||
LEB128.cpp | ||
LLVMBuild.txt | ||
LineIterator.cpp | ||
Locale.cpp | ||
LockFileManager.cpp | ||
MD5.cpp | ||
ManagedStatic.cpp | ||
MathExtras.cpp | ||
Memory.cpp | ||
MemoryBuffer.cpp | ||
MemoryObject.cpp | ||
Mutex.cpp | ||
Options.cpp | ||
Path.cpp | ||
PluginLoader.cpp | ||
PrettyStackTrace.cpp | ||
Process.cpp | ||
Program.cpp | ||
README.txt.system | ||
RWMutex.cpp | ||
RandomNumberGenerator.cpp | ||
Regex.cpp | ||
SHA1.cpp | ||
ScaledNumber.cpp | ||
ScopedPrinter.cpp | ||
SearchForAddressOfSpecialSymbol.cpp | ||
Signals.cpp | ||
SmallPtrSet.cpp | ||
SmallVector.cpp | ||
SourceMgr.cpp | ||
SpecialCaseList.cpp | ||
Statistic.cpp | ||
StreamingMemoryObject.cpp | ||
StringExtras.cpp | ||
StringMap.cpp | ||
StringPool.cpp | ||
StringRef.cpp | ||
StringSaver.cpp | ||
SystemUtils.cpp | ||
TargetParser.cpp | ||
TargetRegistry.cpp | ||
ThreadLocal.cpp | ||
ThreadPool.cpp | ||
Threading.cpp | ||
TimeValue.cpp | ||
Timer.cpp | ||
ToolOutputFile.cpp | ||
Triple.cpp | ||
Twine.cpp | ||
Unicode.cpp | ||
Valgrind.cpp | ||
Watchdog.cpp | ||
YAMLParser.cpp | ||
YAMLTraits.cpp | ||
circular_raw_ostream.cpp | ||
raw_os_ostream.cpp | ||
raw_ostream.cpp | ||
regcclass.h | ||
regcname.h | ||
regcomp.c | ||
regengine.inc | ||
regerror.c | ||
regex2.h | ||
regex_impl.h | ||
regexec.c | ||
regfree.c | ||
regstrlcpy.c | ||
regutils.h |
README.txt.system
Design Of lib/System ==================== The software in this directory is designed to completely shield LLVM from any and all operating system specific functionality. It is not intended to be a complete operating system wrapper (such as ACE), but only to provide the functionality necessary to support LLVM. The software located here, of necessity, has very specific and stringent design rules. Violation of these rules means that cracks in the shield could form and the primary goal of the library is defeated. By consistently using this library, LLVM becomes more easily ported to new platforms since the only thing requiring porting is this library. Complete documentation for the library can be found in the file: llvm/docs/SystemLibrary.html or at this URL: http://llvm.org/docs/SystemLibrary.html While we recommend that you read the more detailed documentation, for the impatient, here's a high level summary of the library's requirements. 1. No system header files are to be exposed through the interface. 2. Std C++ and Std C header files are okay to be exposed through the interface. 3. No exposed system-specific functions. 4. No exposed system-specific data. 5. Data in lib/System classes must use only simple C++ intrinsic types. 6. Errors are handled by returning "true" and setting an optional std::string 7. Library must not throw any exceptions, period. 8. Interface functions must not have throw() specifications. 9. No duplicate function impementations are permitted within an operating system class. To accomplish these requirements, the library has numerous design criteria that must be satisfied. Here's a high level summary of the library's design criteria: 1. No unused functionality (only what LLVM needs) 2. High-Level Interfaces 3. Use Opaque Classes 4. Common Implementations 5. Multiple Implementations 6. Minimize Memory Allocation 7. No Virtual Methods