Subzero: Count lookups of each constant value in the constant pool.

src/IceGlobalContext.cpp

 //===- subzero/src/IceGlobalContext.cpp - Global context defs -------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 125 matching lines @@
 // TypePool maps constants of type KeyType (e.g. float) to pointers to
 // type ValueType (e.g. ConstantFloat).
 template <Type Ty, typename KeyType, typename ValueType> class TypePool {
   TypePool(const TypePool &) = delete;
   TypePool &operator=(const TypePool &) = delete;
 
 public:
   TypePool() = default;
   ValueType *getOrAdd(GlobalContext *Ctx, KeyType Key) {
     auto Iter = Pool.find(Key);
-    if (Iter != Pool.end())
+    if (Iter != Pool.end()) {
+      Iter->second->updateLookupCount();
       return Iter->second;
+    }
     auto *Result = ValueType::create(Ctx, Ty, Key);
     Pool[Key] = Result;
+    Result->updateLookupCount();
     return Result;
   }
   ConstantList getConstantPool() const {
     ConstantList Constants;
     Constants.reserve(Pool.size());
     for (auto &I : Pool)
       Constants.push_back(I.second);
     // The sort (and its KeyCompareLess machinery) is not strictly necessary,
     // but is desirable for producing output that is deterministic across
     // unordered_map::iterator implementations.
@@ skipping 243 matching lines @@
       ProfileBlockInfo->addInitializer(
           VariableDeclaration::RelocInitializer::create(
               Global,
               {RelocOffset::create(this, BlockExecutionCounterOffset)}));
     }
   }
 }
 
 void GlobalContext::lowerGlobals(const IceString &SectionSuffix) {
   TimerMarker T(TimerStack::TT_emitGlobalInitializers, this);
-  const bool DumpGlobalVariables =
-      BuildDefs::dump() &&
-      (Flags.getVerbose() & IceV_GlobalInit & Cfg::defaultVerboseMask()) &&
-      Flags.getVerboseFocusOn().empty();
+  const bool DumpGlobalVariables = BuildDefs::dump() &&
+                                   (Flags.getVerbose() & IceV_GlobalInit) &&
+                                   Flags.getVerboseFocusOn().empty();
   if (DumpGlobalVariables) {
     OstreamLocker L(this);
     Ostream &Stream = getStrDump();
     for (const Ice::VariableDeclaration *Global : Globals) {
       Global->dump(this, Stream);
     }
   }
   if (Flags.getDisableTranslation())
     return;
 
@@ skipping 324 matching lines @@
 }
 
 GlobalContext::~GlobalContext() {
   llvm::DeleteContainerPointers(AllThreadContexts);
   LockedPtr<DestructorArray> Dtors = getDestructors();
   // Destructors are invoked in the opposite object construction order.
   for (const auto &Dtor : reverse_range(*Dtors))
     Dtor();
 }
 
+void GlobalContext::dumpConstantLookupCounts() {
+  if (!BuildDefs::dump())
+    return;
+  const bool DumpCounts = (Flags.getVerbose() & IceV_ConstPoolStats) &&
+                          Flags.getVerboseFocusOn().empty();
+  if (!DumpCounts)
+    return;
+
+  OstreamLocker _(this);
+  Ostream &Str = getStrDump();
+  Str << "Constant pool use stats: count+value+type\n";
+#define X(WhichPool)                                                           \
+  for (auto *C : getConstPool()->WhichPool.getConstantPool()) {                \
+    Str << C->getLookupCount() << " ";                                         \
+    C->dump(Str);                                                              \
+    Str << " " << C->getType() << "\n";                                        \
+  }
+  X(Integers1);
+  X(Integers8);
+  X(Integers16);
+  X(Integers32);
+  X(Integers64);
+  X(Floats);
+  X(Doubles);
+  X(Relocatables);
+  X(ExternRelocatables);
+#undef X
+}
+
 // TODO(stichnot): Consider adding thread-local caches of constant pool entries
 // to reduce contention.
 
 // All locking is done by the getConstantInt[0-9]+() target function.
 Constant *GlobalContext::getConstantInt(Type Ty, int64_t Value) {
   switch (Ty) {
   case IceType_i1:
     return getConstantInt1(Value);
   case IceType_i8:
     return getConstantInt8(Value);
@@ skipping 278 matching lines @@
   Ctx = Func->getContext();
   Active =
       Func->getFocusedTiming() || Ctx->getFlags().getSubzeroTimingEnabled();
   if (Active)
     Ctx->pushTimer(ID, StackID);
 }
 
 ICE_TLS_DEFINE_FIELD(GlobalContext::ThreadContext *, GlobalContext, TLS);
 
 } // end of namespace Ice