Add two files lost in rebase, causing build break

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295595 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Support/DebugCounter.h

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+//===- llvm/Support/DebugCounter.h - Debug counter support ------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// \file This file provides an implementation of debug counters.  Debug counters
+// are a tool that let you narrow down a miscompilation to a specific thing
+// happening.  To give a use case: Imagine you have a file, very large, and you
+// are trying to understand the minimal transformation that breaks it.  Bugpoint
+// and bisection is often helpful here in narrowing it down to a specific pass,
+// but it's still a very large file, and a very complicated pass to try to
+// debug.  That is where debug counting steps in.  You can instrument the pass
+// with a debug counter before it does a certain thing, and depending on the
+// counts, it will either execute that thing or not.  The debug counter itself
+// consists of a skip and a count.  Skip is the number of times shouldExecute
+// needs to be called before it returns true.  Count is the number of times to
+// return true once Skip is 0.  So a skip=47, count=2 ,would skip the first 47
+// executions by returning false from shouldExecute, then execute twice, and
+// then return false again.
+// Note that a counter set to a negative number will always execute.
+
+// For a concrete example, during predicateinfo creation, the renaming pass
+// replaces each use with a renamed use.
+///
+// If I use DEBUG_COUNTER to create a counter called "predicateinfo", and
+// variable name RenameCounter, and then instrument this renaming with a debug
+// counter, like so:
+//
+// if (!DebugCounter::shouldExecute(RenameCounter)
+// <continue or return or whatever not executing looks like>
+//
+// Now I can, from the command line, make it rename or not rename certain uses
+// by setting the skip and count.
+// So for example
+// bin/opt -debug-counter=predicateinfo-skip=47,predicateinfo-count=1
+// will skip renaming the first 47 uses, then rename one, then skip the rest.
+
+#ifndef LLVM_SUPPORT_DEBUGCOUNTER_H
+#define LLVM_SUPPORT_DEBUGCOUNTER_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/UniqueVector.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include <string>
+
+namespace llvm {
+
+class DebugCounter {
+public:
+  /// \brief Returns a reference to the singleton instance.
+  static DebugCounter &instance();
+
+  // Used by the command line option parser to push a new value it parsed.
+  void push_back(const std::string &);
+
+  // Register a counter with the specified name.
+  //
+  // FIXME: Currently, counter registration is required to happen before command
+  // line option parsing. The main reason to register counters is to produce a
+  // nice list of them on the command line, but i'm not sure this is worth it.
+  static unsigned registerCounter(StringRef Name, StringRef Desc) {
+    return instance().addCounter(Name, Desc);
+  }
+  inline static bool shouldExecute(unsigned CounterName) {
+// Compile to nothing when debugging is off
+#ifdef NDEBUG
+    return true;
+#else
+    auto &Us = instance();
+    auto Result = Us.Counters.find(CounterName);
+    if (Result != Us.Counters.end()) {
+      auto &CounterPair = Result->second;
+      // We only execute while the skip (first) is zero and the count (second)
+      // is non-zero.
+      // Negative counters always execute.
+      if (CounterPair.first < 0)
+        return true;
+      if (CounterPair.first != 0) {
+        --CounterPair.first;
+        return false;
+      }
+      if (CounterPair.second < 0)
+        return true;
+      if (CounterPair.second != 0) {
+        --CounterPair.second;
+        return true;
+      }
+      return false;
+    }
+    // Didn't find the counter, should we warn?
+    return true;
+#endif // NDEBUG
+  }
+
+  // Dump or print the current counter set.
+  LLVM_DUMP_METHOD void dump() { print(dbgs()); }
+
+  void print(raw_ostream &OS);
+  
+  // Get the counter ID for a given named counter, or return 0 if none is found.
+  unsigned getCounterId(const std::string &Name) const {
+    return RegisteredCounters.idFor(Name);
+  }
+
+  // Return the number of registered counters.
+  unsigned int getNumCounters() const { return RegisteredCounters.size(); }
+
+  // Return the name and description of the counter with the given ID.
+  std::pair<StringRef, StringRef> getCounterInfo(unsigned ID) const {
+    return std::make_pair(RegisteredCounters[ID], CounterDesc.lookup(ID));
+  }
+
+  // Iterate through the registered counters
+  typedef UniqueVector<std::string> CounterVector;
+  CounterVector::const_iterator begin() const {
+    return RegisteredCounters.begin();
+  }
+  CounterVector::const_iterator end() const { return RegisteredCounters.end(); }
+
+private:
+  unsigned addCounter(const std::string &Name, const std::string &Desc) {
+    unsigned Result = RegisteredCounters.insert(Name);
+    CounterDesc[Result] = Desc;
+    return Result;
+  }
+  DenseMap<unsigned, std::pair<long, long>> Counters;
+  DenseMap<unsigned, std::string> CounterDesc;
+  CounterVector RegisteredCounters;
+};
+
+#define DEBUG_COUNTER(VARNAME, COUNTERNAME, DESC)                              \
+  static const unsigned VARNAME =                                              \
+      DebugCounter::registerCounter(COUNTERNAME, DESC);
+
+} // namespace llvm
+#endif

lib/Support/DebugCounter.cpp

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+#include "llvm/Support/DebugCounter.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/Options.h"
+
+using namespace llvm;
+
+// This class overrides the default list implementation of printing so we
+// can pretty print the list of debug counter options.  This type of
+// dynamic option is pretty rare (basically this and pass lists).
+class DebugCounterList : public cl::list<std::string, DebugCounter> {
+private:
+  using Base = cl::list<std::string, DebugCounter>;
+
+public:
+  template <class... Mods>
+  explicit DebugCounterList(Mods &&... Ms) : Base(std::forward<Mods>(Ms)...) {}
+
+private:
+  void printOptionInfo(size_t GlobalWidth) const override {
+    // This is a variant of from generic_parser_base::printOptionInfo.  Sadly,
+    // it's not easy to make it more usable.  We could get it to print these as
+    // options if we were a cl::opt and registered them, but lists don't have
+    // options, nor does the parser for std::string.  The other mechanisms for
+    // options are global and would pollute the global namespace with our
+    // counters.  Rather than go that route, we have just overridden the
+    // printing, which only a few things call anyway.
+    outs() << "  -" << ArgStr;
+    // All of the other options in CommandLine.cpp use ArgStr.size() + 6 for
+    // width, so we do the same.
+    Option::printHelpStr(HelpStr, GlobalWidth, ArgStr.size() + 6);
+    const auto &CounterInstance = DebugCounter::instance();
+    for (auto Name : CounterInstance) {
+      const auto Info =
+          CounterInstance.getCounterInfo(CounterInstance.getCounterId(Name));
+      size_t NumSpaces = GlobalWidth - Info.first.size() - 8;
+      outs() << "    =" << Info.first;
+      outs().indent(NumSpaces) << " -   " << Info.second << '\n';
+    }
+  }
+};
+
+// Create our command line option.
+static DebugCounterList DebugCounterOption(
+    "debug-counter",
+    cl::desc("Comma separated list of debug counter skip and count"),
+    cl::CommaSeparated, cl::ZeroOrMore, cl::location(DebugCounter::instance()));
+
+static ManagedStatic<DebugCounter> DC;
+
+DebugCounter &DebugCounter::instance() { return *DC; }
+
+// This is called by the command line parser when it sees a value for the
+// debug-counter option defined above.
+void DebugCounter::push_back(const std::string &Val) {
+  if (Val.empty())
+    return;
+  // The strings should come in as counter=value
+  auto CounterPair = StringRef(Val).split('=');
+  if (CounterPair.second.empty()) {
+    errs() << "DebugCounter Error: " << Val << " does not have an = in it\n";
+    return;
+  }
+  // Now we have counter=value.
+  // First, process value.
+  long CounterVal;
+  if (CounterPair.second.getAsInteger(0, CounterVal)) {
+    errs() << "DebugCounter Error: " << CounterPair.second
+           << " is not a number\n";
+    return;
+  }
+  // Now we need to see if this is the skip or the count, remove the suffix, and
+  // add it to the counter values.
+  if (CounterPair.first.endswith("-skip")) {
+    auto CounterName = CounterPair.first.drop_back(5);
+    unsigned CounterID = RegisteredCounters.idFor(CounterName);
+    if (!CounterID) {
+      errs() << "DebugCounter Error: " << CounterName
+             << " is not a registered counter\n";
+      return;
+    }
+
+    auto Res = Counters.insert({CounterID, {-1, -1}});
+    Res.first->second.first = CounterVal;
+  } else if (CounterPair.first.endswith("-count")) {
+    auto CounterName = CounterPair.first.drop_back(6);
+    unsigned CounterID = RegisteredCounters.idFor(CounterName);
+    if (!CounterID) {
+      errs() << "DebugCounter Error: " << CounterName
+             << " is not a registered counter\n";
+      return;
+    }
+
+    auto Res = Counters.insert({CounterID, {-1, -1}});
+    Res.first->second.second = CounterVal;
+  } else {
+    errs() << "DebugCounter Error: " << CounterPair.first
+           << " does not end with -skip or -count\n";
+  }
+}
+
+void DebugCounter::print(raw_ostream &OS) {
+  OS << "Counters and values:\n";
+  for (const auto &KV : Counters)
+    OS << left_justify(RegisteredCounters[KV.first], 32) << ": {"
+       << KV.second.first << "," << KV.second.second << "}\n";
+}