It's not necessary to do rounding for alloca operations when the requested
alignment is equal to the stack alignment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40004 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/IntrinsicEmitter.cpp b/utils/TableGen/IntrinsicEmitter.cpp
new file mode 100644
index 0000000..89e9621
--- /dev/null
+++ b/utils/TableGen/IntrinsicEmitter.cpp
@@ -0,0 +1,389 @@
+//===- IntrinsicEmitter.cpp - Generate intrinsic information --------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Chris Lattner and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This tablegen backend emits information about intrinsic functions.
+//
+//===----------------------------------------------------------------------===//
+
+#include "IntrinsicEmitter.h"
+#include "Record.h"
+#include "llvm/ADT/StringExtras.h"
+#include <algorithm>
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+// IntrinsicEmitter Implementation
+//===----------------------------------------------------------------------===//
+
+void IntrinsicEmitter::run(std::ostream &OS) {
+  EmitSourceFileHeader("Intrinsic Function Source Fragment", OS);
+  
+  std::vector<CodeGenIntrinsic> Ints = LoadIntrinsics(Records);
+
+  // Emit the enum information.
+  EmitEnumInfo(Ints, OS);
+
+  // Emit the intrinsic ID -> name table.
+  EmitIntrinsicToNameTable(Ints, OS);
+  
+  // Emit the function name recognizer.
+  EmitFnNameRecognizer(Ints, OS);
+  
+  // Emit the intrinsic verifier.
+  EmitVerifier(Ints, OS);
+  
+  // Emit the intrinsic declaration generator.
+  EmitGenerator(Ints, OS);
+  
+  // Emit mod/ref info for each function.
+  EmitModRefInfo(Ints, OS);
+  
+  // Emit table of non-memory accessing intrinsics.
+  EmitNoMemoryInfo(Ints, OS);
+  
+  // Emit side effect info for each intrinsic.
+  EmitSideEffectInfo(Ints, OS);
+
+  // Emit a list of intrinsics with corresponding GCC builtins.
+  EmitGCCBuiltinList(Ints, OS);
+
+  // Emit code to translate GCC builtins into LLVM intrinsics.
+  EmitIntrinsicToGCCBuiltinMap(Ints, OS);
+}
+
+void IntrinsicEmitter::EmitEnumInfo(const std::vector<CodeGenIntrinsic> &Ints,
+                                    std::ostream &OS) {
+  OS << "// Enum values for Intrinsics.h\n";
+  OS << "#ifdef GET_INTRINSIC_ENUM_VALUES\n";
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
+    OS << "    " << Ints[i].EnumName;
+    OS << ((i != e-1) ? ", " : "  ");
+    OS << std::string(40-Ints[i].EnumName.size(), ' ') 
+      << "// " << Ints[i].Name << "\n";
+  }
+  OS << "#endif\n\n";
+}
+
+void IntrinsicEmitter::
+EmitFnNameRecognizer(const std::vector<CodeGenIntrinsic> &Ints, 
+                     std::ostream &OS) {
+  // Build a function name -> intrinsic name mapping.
+  std::map<std::string, unsigned> IntMapping;
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i)
+    IntMapping[Ints[i].Name] = i;
+    
+  OS << "// Function name -> enum value recognizer code.\n";
+  OS << "#ifdef GET_FUNCTION_RECOGNIZER\n";
+  OS << "  switch (Name[5]) {\n";
+  OS << "  default:\n";
+  // Emit the intrinsics in sorted order.
+  char LastChar = 0;
+  for (std::map<std::string, unsigned>::iterator I = IntMapping.begin(),
+       E = IntMapping.end(); I != E; ++I) {
+    if (I->first[5] != LastChar) {
+      LastChar = I->first[5];
+      OS << "    break;\n";
+      OS << "  case '" << LastChar << "':\n";
+    }
+    
+    // For overloaded intrinsics, only the prefix needs to match
+    if (Ints[I->second].isOverloaded)
+      OS << "    if (Len >= " << I->first.size()
+       << " && !memcmp(Name, \"" << I->first << "\", " << I->first.size()
+       << ")) return Intrinsic::" << Ints[I->second].EnumName << ";\n";
+    else 
+      OS << "    if (Len == " << I->first.size()
+         << " && !memcmp(Name, \"" << I->first << "\", Len)) return Intrinsic::"
+         << Ints[I->second].EnumName << ";\n";
+  }
+  OS << "  }\n";
+  OS << "#endif\n\n";
+}
+
+void IntrinsicEmitter::
+EmitIntrinsicToNameTable(const std::vector<CodeGenIntrinsic> &Ints, 
+                         std::ostream &OS) {
+  OS << "// Intrinsic ID to name table\n";
+  OS << "#ifdef GET_INTRINSIC_NAME_TABLE\n";
+  OS << "  // Note that entry #0 is the invalid intrinsic!\n";
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i)
+    OS << "  \"" << Ints[i].Name << "\",\n";
+  OS << "#endif\n\n";
+}
+
+static bool EmitTypeVerify(std::ostream &OS, Record *ArgType) {
+  if (ArgType->getValueAsString("TypeVal") == "...")  return true;
+  
+  OS << "(int)" << ArgType->getValueAsString("TypeVal") << ", ";
+  // If this is an integer type, check the width is correct.
+  if (ArgType->isSubClassOf("LLVMIntegerType"))
+    OS << ArgType->getValueAsInt("Width") << ", ";
+
+  // If this is a vector type, check that the subtype and size are correct.
+  else if (ArgType->isSubClassOf("LLVMVectorType")) {
+    EmitTypeVerify(OS, ArgType->getValueAsDef("ElTy"));
+    OS << ArgType->getValueAsInt("NumElts") << ", ";
+  }
+  
+  return false;
+}
+
+static void EmitTypeGenerate(std::ostream &OS, Record *ArgType, 
+                             unsigned &ArgNo) {
+  if (ArgType->isSubClassOf("LLVMIntegerType")) {
+    unsigned BitWidth = ArgType->getValueAsInt("Width");
+    // NOTE: The ArgNo variable here is not the absolute argument number, it is
+    // the index of the "arbitrary" type in the Tys array passed to the
+    // Intrinsic::getDeclaration function. Consequently, we only want to
+    // increment it when we actually hit an arbitrary integer type which is
+    // identified by BitWidth == 0. Getting this wrong leads to very subtle
+    // bugs!
+    if (BitWidth == 0)
+      OS << "Tys[" << ArgNo++ << "]";
+    else
+      OS << "IntegerType::get(" << BitWidth << ")";
+  } else if (ArgType->isSubClassOf("LLVMVectorType")) {
+    OS << "VectorType::get(";
+    EmitTypeGenerate(OS, ArgType->getValueAsDef("ElTy"), ArgNo);
+    OS << ", " << ArgType->getValueAsInt("NumElts") << ")";
+  } else if (ArgType->isSubClassOf("LLVMPointerType")) {
+    OS << "PointerType::get(";
+    EmitTypeGenerate(OS, ArgType->getValueAsDef("ElTy"), ArgNo);
+    OS << ")";
+  } else if (ArgType->isSubClassOf("LLVMEmptyStructType")) {
+    OS << "StructType::get(std::vector<const Type *>())";
+  } else {
+    OS << "Type::getPrimitiveType(";
+    OS << ArgType->getValueAsString("TypeVal") << ")";
+  }
+}
+
+/// RecordListComparator - Provide a determinstic comparator for lists of
+/// records.
+namespace {
+  struct RecordListComparator {
+    bool operator()(const std::vector<Record*> &LHS,
+                    const std::vector<Record*> &RHS) const {
+      unsigned i = 0;
+      do {
+        if (i == RHS.size()) return false;  // RHS is shorter than LHS.
+        if (LHS[i] != RHS[i])
+          return LHS[i]->getName() < RHS[i]->getName();
+      } while (++i != LHS.size());
+      
+      return i != RHS.size();
+    }
+  };
+}
+
+void IntrinsicEmitter::EmitVerifier(const std::vector<CodeGenIntrinsic> &Ints, 
+                                    std::ostream &OS) {
+  OS << "// Verifier::visitIntrinsicFunctionCall code.\n";
+  OS << "#ifdef GET_INTRINSIC_VERIFIER\n";
+  OS << "  switch (ID) {\n";
+  OS << "  default: assert(0 && \"Invalid intrinsic!\");\n";
+  
+  // This checking can emit a lot of very common code.  To reduce the amount of
+  // code that we emit, batch up cases that have identical types.  This avoids
+  // problems where GCC can run out of memory compiling Verifier.cpp.
+  typedef std::map<std::vector<Record*>, std::vector<unsigned>, 
+    RecordListComparator> MapTy;
+  MapTy UniqueArgInfos;
+  
+  // Compute the unique argument type info.
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i)
+    UniqueArgInfos[Ints[i].ArgTypeDefs].push_back(i);
+
+  // Loop through the array, emitting one comparison for each batch.
+  for (MapTy::iterator I = UniqueArgInfos.begin(),
+       E = UniqueArgInfos.end(); I != E; ++I) {
+    for (unsigned i = 0, e = I->second.size(); i != e; ++i) {
+      OS << "  case Intrinsic::" << Ints[I->second[i]].EnumName << ":\t\t// "
+         << Ints[I->second[i]].Name << "\n";
+    }
+    
+    const std::vector<Record*> &ArgTypes = I->first;
+    OS << "    VerifyIntrinsicPrototype(ID, IF, ";
+    bool VarArg = false;
+    for (unsigned j = 0; j != ArgTypes.size(); ++j) {
+      VarArg = EmitTypeVerify(OS, ArgTypes[j]);
+      if (VarArg) {
+        if ((j+1) != ArgTypes.size())
+          throw "Var arg type not last argument";
+        break;
+      }
+    }
+      
+    OS << (VarArg ? "-2);\n" : "-1);\n");
+    OS << "    break;\n";
+  }
+  OS << "  }\n";
+  OS << "#endif\n\n";
+}
+
+void IntrinsicEmitter::EmitGenerator(const std::vector<CodeGenIntrinsic> &Ints, 
+                                     std::ostream &OS) {
+  OS << "// Code for generating Intrinsic function declarations.\n";
+  OS << "#ifdef GET_INTRINSIC_GENERATOR\n";
+  OS << "  switch (id) {\n";
+  OS << "  default: assert(0 && \"Invalid intrinsic!\");\n";
+  
+  // Similar to GET_INTRINSIC_VERIFIER, batch up cases that have identical
+  // types.
+  typedef std::map<std::vector<Record*>, std::vector<unsigned>, 
+    RecordListComparator> MapTy;
+  MapTy UniqueArgInfos;
+  
+  // Compute the unique argument type info.
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i)
+    UniqueArgInfos[Ints[i].ArgTypeDefs].push_back(i);
+
+  // Loop through the array, emitting one generator for each batch.
+  for (MapTy::iterator I = UniqueArgInfos.begin(),
+       E = UniqueArgInfos.end(); I != E; ++I) {
+    for (unsigned i = 0, e = I->second.size(); i != e; ++i) {
+      OS << "  case Intrinsic::" << Ints[I->second[i]].EnumName << ":\t\t// "
+         << Ints[I->second[i]].Name << "\n";
+    }
+    
+    const std::vector<Record*> &ArgTypes = I->first;
+    unsigned N = ArgTypes.size();
+
+    if (ArgTypes[N-1]->getValueAsString("TypeVal") == "...") {
+      OS << "    IsVarArg = true;\n";
+      --N;
+    }
+    
+    unsigned ArgNo = 0;
+    OS << "    ResultTy = ";
+    EmitTypeGenerate(OS, ArgTypes[0], ArgNo);
+    OS << ";\n";
+    
+    for (unsigned j = 1; j != N; ++j) {
+      OS << "    ArgTys.push_back(";
+      EmitTypeGenerate(OS, ArgTypes[j], ArgNo);
+      OS << ");\n";
+    }
+    OS << "    break;\n";
+  }
+  OS << "  }\n";
+  OS << "#endif\n\n";
+}
+
+void IntrinsicEmitter::EmitModRefInfo(const std::vector<CodeGenIntrinsic> &Ints,
+                                      std::ostream &OS) {
+  OS << "// BasicAliasAnalysis code.\n";
+  OS << "#ifdef GET_MODREF_BEHAVIOR\n";
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
+    switch (Ints[i].ModRef) {
+    default: break;
+    case CodeGenIntrinsic::NoMem:
+      OS << "  NoMemoryTable->push_back(\"" << Ints[i].Name << "\");\n";
+      break;
+    case CodeGenIntrinsic::ReadArgMem:
+    case CodeGenIntrinsic::ReadMem:
+      OS << "  OnlyReadsMemoryTable->push_back(\"" << Ints[i].Name << "\");\n";
+      break;
+    }
+  }
+  OS << "#endif\n\n";
+}
+
+void IntrinsicEmitter::
+EmitNoMemoryInfo(const std::vector<CodeGenIntrinsic> &Ints, std::ostream &OS) {
+  OS << "// SelectionDAGIsel code.\n";
+  OS << "#ifdef GET_NO_MEMORY_INTRINSICS\n";
+  OS << "  switch (IntrinsicID) {\n";
+  OS << "  default: break;\n";
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
+    switch (Ints[i].ModRef) {
+    default: break;
+    case CodeGenIntrinsic::NoMem:
+      OS << "  case Intrinsic::" << Ints[i].EnumName << ":\n";
+      break;
+    }
+  }
+  OS << "    return true; // These intrinsics have no side effects.\n";
+  OS << "  }\n";
+  OS << "#endif\n\n";
+}
+
+void IntrinsicEmitter::
+EmitSideEffectInfo(const std::vector<CodeGenIntrinsic> &Ints, std::ostream &OS){
+  OS << "// Return true if doesn't access or only reads memory.\n";
+  OS << "#ifdef GET_SIDE_EFFECT_INFO\n";
+  OS << "  switch (IntrinsicID) {\n";
+  OS << "  default: break;\n";
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
+    switch (Ints[i].ModRef) {
+    default: break;
+    case CodeGenIntrinsic::NoMem:
+    case CodeGenIntrinsic::ReadArgMem:
+    case CodeGenIntrinsic::ReadMem:
+      OS << "  case Intrinsic::" << Ints[i].EnumName << ":\n";
+      break;
+    }
+  }
+  OS << "    return true; // These intrinsics have no side effects.\n";
+  OS << "  }\n";
+  OS << "#endif\n\n";
+}
+
+void IntrinsicEmitter::
+EmitGCCBuiltinList(const std::vector<CodeGenIntrinsic> &Ints, std::ostream &OS){
+  OS << "// Get the GCC builtin that corresponds to an LLVM intrinsic.\n";
+  OS << "#ifdef GET_GCC_BUILTIN_NAME\n";
+  OS << "  switch (F->getIntrinsicID()) {\n";
+  OS << "  default: BuiltinName = \"\"; break;\n";
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
+    if (!Ints[i].GCCBuiltinName.empty()) {
+      OS << "  case Intrinsic::" << Ints[i].EnumName << ": BuiltinName = \""
+         << Ints[i].GCCBuiltinName << "\"; break;\n";
+    }
+  }
+  OS << "  }\n";
+  OS << "#endif\n\n";
+}
+
+void IntrinsicEmitter::
+EmitIntrinsicToGCCBuiltinMap(const std::vector<CodeGenIntrinsic> &Ints, 
+                             std::ostream &OS) {
+  typedef std::map<std::pair<std::string, std::string>, std::string> BIMTy;
+  BIMTy BuiltinMap;
+  for (unsigned i = 0, e = Ints.size(); i != e; ++i) {
+    if (!Ints[i].GCCBuiltinName.empty()) {
+      std::pair<std::string, std::string> Key(Ints[i].GCCBuiltinName,
+                                              Ints[i].TargetPrefix);
+      if (!BuiltinMap.insert(std::make_pair(Key, Ints[i].EnumName)).second)
+        throw "Intrinsic '" + Ints[i].TheDef->getName() +
+              "': duplicate GCC builtin name!";
+    }
+  }
+  
+  OS << "// Get the LLVM intrinsic that corresponds to a GCC builtin.\n";
+  OS << "// This is used by the C front-end.  The GCC builtin name is passed\n";
+  OS << "// in as BuiltinName, and a target prefix (e.g. 'ppc') is passed\n";
+  OS << "// in as TargetPrefix.  The result is assigned to 'IntrinsicID'.\n";
+  OS << "#ifdef GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN\n";
+  OS << "  if (0);\n";
+  // Note: this could emit significantly better code if we cared.
+  for (BIMTy::iterator I = BuiltinMap.begin(), E = BuiltinMap.end();I != E;++I){
+    OS << "  else if (";
+    if (!I->first.second.empty()) {
+      // Emit this as a strcmp, so it can be constant folded by the FE.
+      OS << "!strcmp(TargetPrefix, \"" << I->first.second << "\") &&\n"
+         << "           ";
+    }
+    OS << "!strcmp(BuiltinName, \"" << I->first.first << "\"))\n";
+    OS << "    IntrinsicID = Intrinsic::" << I->second << ";\n";
+  }
+  OS << "  else\n";
+  OS << "    IntrinsicID = Intrinsic::not_intrinsic;\n";
+  OS << "#endif\n\n";
+}