1 files changed, 223 insertions, 0 deletions
diff --git a/llvm/lib/IR/Mangler.cpp b/llvm/lib/IR/Mangler.cpp
new file mode 100644
index 0000000000000..d73f748b0584d
--- /dev/null
+++ b/llvm/lib/IR/Mangler.cpp
@@ -0,0 +1,223 @@
+//===-- Mangler.cpp - Self-contained c/asm llvm name mangler --------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Unified name mangler for assembly backends.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IR/Mangler.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace llvm;
+
+namespace {
+enum ManglerPrefixTy {
+  Default,      ///< Emit default string before each symbol.
+  Private,      ///< Emit "private" prefix before each symbol.
+  LinkerPrivate ///< Emit "linker private" prefix before each symbol.
+};
+}
+
+static void getNameWithPrefixImpl(raw_ostream &OS, const Twine &GVName,
+                                  ManglerPrefixTy PrefixTy,
+                                  const DataLayout &DL, char Prefix) {
+  SmallString<256> TmpData;
+  StringRef Name = GVName.toStringRef(TmpData);
+  assert(!Name.empty() && "getNameWithPrefix requires non-empty name");
+
+  // No need to do anything special if the global has the special "do not
+  // mangle" flag in the name.
+  if (Name[0] == '\1') {
+    OS << Name.substr(1);
+    return;
+  }
+
+  if (DL.doNotMangleLeadingQuestionMark() && Name[0] == '?')
+    Prefix = '\0';
+
+  if (PrefixTy == Private)
+    OS << DL.getPrivateGlobalPrefix();
+  else if (PrefixTy == LinkerPrivate)
+    OS << DL.getLinkerPrivateGlobalPrefix();
+
+  if (Prefix != '\0')
+    OS << Prefix;
+
+  // If this is a simple string that doesn't need escaping, just append it.
+  OS << Name;
+}
+
+static void getNameWithPrefixImpl(raw_ostream &OS, const Twine &GVName,
+                                  const DataLayout &DL,
+                                  ManglerPrefixTy PrefixTy) {
+  char Prefix = DL.getGlobalPrefix();
+  return getNameWithPrefixImpl(OS, GVName, PrefixTy, DL, Prefix);
+}
+
+void Mangler::getNameWithPrefix(raw_ostream &OS, const Twine &GVName,
+                                const DataLayout &DL) {
+  return getNameWithPrefixImpl(OS, GVName, DL, Default);
+}
+
+void Mangler::getNameWithPrefix(SmallVectorImpl<char> &OutName,
+                                const Twine &GVName, const DataLayout &DL) {
+  raw_svector_ostream OS(OutName);
+  char Prefix = DL.getGlobalPrefix();
+  return getNameWithPrefixImpl(OS, GVName, Default, DL, Prefix);
+}
+
+static bool hasByteCountSuffix(CallingConv::ID CC) {
+  switch (CC) {
+  case CallingConv::X86_FastCall:
+  case CallingConv::X86_StdCall:
+  case CallingConv::X86_VectorCall:
+    return true;
+  default:
+    return false;
+  }
+}
+
+/// Microsoft fastcall and stdcall functions require a suffix on their name
+/// indicating the number of words of arguments they take.
+static void addByteCountSuffix(raw_ostream &OS, const Function *F,
+                               const DataLayout &DL) {
+  // Calculate arguments size total.
+  unsigned ArgWords = 0;
+  for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
+       AI != AE; ++AI) {
+    Type *Ty = AI->getType();
+    // 'Dereference' type in case of byval or inalloca parameter attribute.
+    if (AI->hasByValOrInAllocaAttr())
+      Ty = cast<PointerType>(Ty)->getElementType();
+    // Size should be aligned to pointer size.
+    unsigned PtrSize = DL.getPointerSize();
+    ArgWords += alignTo(DL.getTypeAllocSize(Ty), PtrSize);
+  }
+
+  OS << '@' << ArgWords;
+}
+
+void Mangler::getNameWithPrefix(raw_ostream &OS, const GlobalValue *GV,
+                                bool CannotUsePrivateLabel) const {
+  ManglerPrefixTy PrefixTy = Default;
+  if (GV->hasPrivateLinkage()) {
+    if (CannotUsePrivateLabel)
+      PrefixTy = LinkerPrivate;
+    else
+      PrefixTy = Private;
+  }
+
+  const DataLayout &DL = GV->getParent()->getDataLayout();
+  if (!GV->hasName()) {
+    // Get the ID for the global, assigning a new one if we haven't got one
+    // already.
+    unsigned &ID = AnonGlobalIDs[GV];
+    if (ID == 0)
+      ID = AnonGlobalIDs.size();
+
+    // Must mangle the global into a unique ID.
+    getNameWithPrefixImpl(OS, "__unnamed_" + Twine(ID), DL, PrefixTy);
+    return;
+  }
+
+  StringRef Name = GV->getName();
+  char Prefix = DL.getGlobalPrefix();
+
+  // Mangle functions with Microsoft calling conventions specially.  Only do
+  // this mangling for x86_64 vectorcall and 32-bit x86.
+  const Function *MSFunc = dyn_cast<Function>(GV);
+
+  // Don't add byte count suffixes when '\01' or '?' are in the first
+  // character.
+  if (Name.startswith("\01") ||
+      (DL.doNotMangleLeadingQuestionMark() && Name.startswith("?")))
+    MSFunc = nullptr;
+
+  CallingConv::ID CC =
+      MSFunc ? MSFunc->getCallingConv() : (unsigned)CallingConv::C;
+  if (!DL.hasMicrosoftFastStdCallMangling() &&
+      CC != CallingConv::X86_VectorCall)
+    MSFunc = nullptr;
+  if (MSFunc) {
+    if (CC == CallingConv::X86_FastCall)
+      Prefix = '@'; // fastcall functions have an @ prefix instead of _.
+    else if (CC == CallingConv::X86_VectorCall)
+      Prefix = '\0'; // vectorcall functions have no prefix.
+  }
+
+  getNameWithPrefixImpl(OS, Name, PrefixTy, DL, Prefix);
+
+  if (!MSFunc)
+    return;
+
+  // If we are supposed to add a microsoft-style suffix for stdcall, fastcall,
+  // or vectorcall, add it.  These functions have a suffix of @N where N is the
+  // cumulative byte size of all of the parameters to the function in decimal.
+  if (CC == CallingConv::X86_VectorCall)
+    OS << '@'; // vectorcall functions use a double @ suffix.
+  FunctionType *FT = MSFunc->getFunctionType();
+  if (hasByteCountSuffix(CC) &&
+      // "Pure" variadic functions do not receive @0 suffix.
+      (!FT->isVarArg() || FT->getNumParams() == 0 ||
+       (FT->getNumParams() == 1 && MSFunc->hasStructRetAttr())))
+    addByteCountSuffix(OS, MSFunc, DL);
+}
+
+void Mangler::getNameWithPrefix(SmallVectorImpl<char> &OutName,
+                                const GlobalValue *GV,
+                                bool CannotUsePrivateLabel) const {
+  raw_svector_ostream OS(OutName);
+  getNameWithPrefix(OS, GV, CannotUsePrivateLabel);
+}
+
+void llvm::emitLinkerFlagsForGlobalCOFF(raw_ostream &OS, const GlobalValue *GV,
+                                        const Triple &TT, Mangler &Mangler) {
+  if (!GV->hasDLLExportStorageClass() || GV->isDeclaration())
+    return;
+
+  if (TT.isWindowsMSVCEnvironment())
+    OS << " /EXPORT:";
+  else
+    OS << " -export:";
+
+  if (TT.isWindowsGNUEnvironment() || TT.isWindowsCygwinEnvironment()) {
+    std::string Flag;
+    raw_string_ostream FlagOS(Flag);
+    Mangler.getNameWithPrefix(FlagOS, GV, false);
+    FlagOS.flush();
+    if (Flag[0] == GV->getParent()->getDataLayout().getGlobalPrefix())
+      OS << Flag.substr(1);
+    else
+      OS << Flag;
+  } else {
+    Mangler.getNameWithPrefix(OS, GV, false);
+  }
+
+  if (!GV->getValueType()->isFunctionTy()) {
+    if (TT.isWindowsMSVCEnvironment())
+      OS << ",DATA";
+    else
+      OS << ",data";
+  }
+}
+
+void llvm::emitLinkerFlagsForUsedCOFF(raw_ostream &OS, const GlobalValue *GV,
+                                      const Triple &T, Mangler &M) {
+  if (!T.isWindowsMSVCEnvironment())
+    return;
+
+  OS << " /INCLUDE:";
+  M.getNameWithPrefix(OS, GV, false);
+}
+