diff options
Diffstat (limited to 'contrib/llvm/lib/Support/Debug.cpp')
| -rw-r--r-- | contrib/llvm/lib/Support/Debug.cpp | 134 | 
1 files changed, 134 insertions, 0 deletions
| diff --git a/contrib/llvm/lib/Support/Debug.cpp b/contrib/llvm/lib/Support/Debug.cpp new file mode 100644 index 000000000000..ad4d4ef1d928 --- /dev/null +++ b/contrib/llvm/lib/Support/Debug.cpp @@ -0,0 +1,134 @@ +//===-- Debug.cpp - An easy way to add debug output to your code ----------===// +// +//                     The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements a handy way of adding debugging information to your +// code, without it being enabled all of the time, and without having to add +// command line options to enable it. +// +// In particular, just wrap your code with the DEBUG() macro, and it will be +// enabled automatically if you specify '-debug' on the command-line. +// Alternatively, you can also use the SET_DEBUG_TYPE("foo") macro to specify +// that your debug code belongs to class "foo".  Then, on the command line, you +// can specify '-debug-only=foo' to enable JUST the debug information for the +// foo class. +// +// When compiling without assertions, the -debug-* options and all code in +// DEBUG() statements disappears, so it does not affect the runtime of the code. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/Debug.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/Signals.h" +#include "llvm/Support/circular_raw_ostream.h" + +using namespace llvm; + +// All Debug.h functionality is a no-op in NDEBUG mode. +#ifndef NDEBUG +bool llvm::DebugFlag;  // DebugFlag - Exported boolean set by the -debug option + +// -debug - Command line option to enable the DEBUG statements in the passes. +// This flag may only be enabled in debug builds. +static cl::opt<bool, true> +Debug("debug", cl::desc("Enable debug output"), cl::Hidden, +      cl::location(DebugFlag)); + +// -debug-buffer-size - Buffer the last N characters of debug output +//until program termination. +static cl::opt<unsigned> +DebugBufferSize("debug-buffer-size", +                cl::desc("Buffer the last N characters of debug output " +                         "until program termination. " +                         "[default 0 -- immediate print-out]"), +                cl::Hidden, +                cl::init(0)); + +static std::string CurrentDebugType; + +namespace { + +struct DebugOnlyOpt { +  void operator=(const std::string &Val) const { +    DebugFlag |= !Val.empty(); +    CurrentDebugType = Val; +  } +}; + +} + +static DebugOnlyOpt DebugOnlyOptLoc; + +static cl::opt<DebugOnlyOpt, true, cl::parser<std::string> > +DebugOnly("debug-only", cl::desc("Enable a specific type of debug output"), +          cl::Hidden, cl::value_desc("debug string"), +          cl::location(DebugOnlyOptLoc), cl::ValueRequired); + +// Signal handlers - dump debug output on termination. +static void debug_user_sig_handler(void *Cookie) { +  // This is a bit sneaky.  Since this is under #ifndef NDEBUG, we +  // know that debug mode is enabled and dbgs() really is a +  // circular_raw_ostream.  If NDEBUG is defined, then dbgs() == +  // errs() but this will never be invoked. +  llvm::circular_raw_ostream *dbgout = +    static_cast<llvm::circular_raw_ostream *>(&llvm::dbgs()); +  dbgout->flushBufferWithBanner(); +} + +// isCurrentDebugType - Return true if the specified string is the debug type +// specified on the command line, or if none was specified on the command line +// with the -debug-only=X option. +// +bool llvm::isCurrentDebugType(const char *DebugType) { +  return CurrentDebugType.empty() || DebugType == CurrentDebugType; +} + +/// setCurrentDebugType - Set the current debug type, as if the -debug-only=X +/// option were specified.  Note that DebugFlag also needs to be set to true for +/// debug output to be produced. +/// +void llvm::setCurrentDebugType(const char *Type) { +  CurrentDebugType = Type; +} + +/// dbgs - Return a circular-buffered debug stream. +raw_ostream &llvm::dbgs() { +  // Do one-time initialization in a thread-safe way. +  static struct dbgstream { +    circular_raw_ostream strm; + +    dbgstream() : +        strm(errs(), "*** Debug Log Output ***\n", +             (!EnableDebugBuffering || !DebugFlag) ? 0 : DebugBufferSize) { +      if (EnableDebugBuffering && DebugFlag && DebugBufferSize != 0) +        // TODO: Add a handler for SIGUSER1-type signals so the user can +        // force a debug dump. +        sys::AddSignalHandler(&debug_user_sig_handler, nullptr); +      // Otherwise we've already set the debug stream buffer size to +      // zero, disabling buffering so it will output directly to errs(). +    } +  } thestrm; + +  return thestrm.strm; +} + +#else +// Avoid "has no symbols" warning. +namespace llvm { +  /// dbgs - Return errs(). +  raw_ostream &dbgs() { +    return errs(); +  } +} + +#endif + +/// EnableDebugBuffering - Turn on signal handler installation. +/// +bool llvm::EnableDebugBuffering = false; | 
