1 files changed, 55 insertions, 41 deletions

diff --git a/lib/IR/Mangler.cpp b/lib/IR/Mangler.cpp
index 27d973b94f0a..5eeb7978e2f3 100644
--- a/lib/IR/Mangler.cpp
+++ b/lib/IR/Mangler.cpp
@@ -22,23 +22,25 @@ using namespace llvm;
 
 static void getNameWithPrefixx(raw_ostream &OS, const Twine &GVName,
                               Mangler::ManglerPrefixTy PrefixTy,
-                              const DataLayout &DL, bool UseAt) {
+                              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 (PrefixTy == Mangler::Private)
     OS << DL.getPrivateGlobalPrefix();
   else if (PrefixTy == Mangler::LinkerPrivate)
     OS << DL.getLinkerPrivateGlobalPrefix();
 
-  if (UseAt) {
-    OS << '@';
-  } else {
-    char Prefix = DL.getGlobalPrefix();
-    if (Prefix != '\0')
-      OS << Prefix;
-  }
+  if (Prefix != '\0')
+    OS << Prefix;
 
   // If this is a simple string that doesn't need escaping, just append it.
   OS << Name;
@@ -46,7 +48,8 @@ static void getNameWithPrefixx(raw_ostream &OS, const Twine &GVName,
 
 void Mangler::getNameWithPrefix(raw_ostream &OS, const Twine &GVName,
                                 ManglerPrefixTy PrefixTy) const {
-  return getNameWithPrefixx(OS, GVName, PrefixTy, *DL, false);
+  char Prefix = DL->getGlobalPrefix();
+  return getNameWithPrefixx(OS, GVName, PrefixTy, *DL, Prefix);
 }
 
 void Mangler::getNameWithPrefix(SmallVectorImpl<char> &OutName,
@@ -56,11 +59,21 @@ void Mangler::getNameWithPrefix(SmallVectorImpl<char> &OutName,
   return getNameWithPrefix(OS, GVName, PrefixTy);
 }
 
-/// AddFastCallStdCallSuffix - Microsoft fastcall and stdcall functions require
-/// a suffix on their name indicating the number of words of arguments they
-/// take.
-static void AddFastCallStdCallSuffix(raw_ostream &OS, const Function *F,
-                                     const DataLayout &TD) {
+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 &TD) {
   // Calculate arguments size total.
   unsigned ArgWords = 0;
   for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
@@ -69,8 +82,9 @@ static void AddFastCallStdCallSuffix(raw_ostream &OS, const Function *F,
     // 'Dereference' type in case of byval or inalloca parameter attribute.
     if (AI->hasByValOrInAllocaAttr())
       Ty = cast<PointerType>(Ty)->getElementType();
-    // Size should be aligned to DWORD boundary
-    ArgWords += ((TD.getTypeAllocSize(Ty) + 3)/4)*4;
+    // Size should be aligned to pointer size.
+    unsigned PtrSize = TD.getPointerSize();
+    ArgWords += RoundUpToAlignment(TD.getTypeAllocSize(Ty), PtrSize);
   }
 
   OS << '@' << ArgWords;
@@ -99,41 +113,41 @@ void Mangler::getNameWithPrefix(raw_ostream &OS, const GlobalValue *GV,
   }
 
   StringRef Name = GV->getName();
-
-  // 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;
-  }
-
-  bool UseAt = false;
-  const Function *MSFunc = nullptr;
-  CallingConv::ID CC;
-  if (DL->hasMicrosoftFastStdCallMangling()) {
-    if ((MSFunc = dyn_cast<Function>(GV))) {
-      CC = MSFunc->getCallingConv();
-      // fastcall functions need to start with @ instead of _.
-      if (CC == CallingConv::X86_FastCall)
-        UseAt = true;
-    }
+  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);
+  if (Name.startswith("\01"))
+    MSFunc = nullptr; // Don't mangle when \01 is present.
+  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.
   }
 
-  getNameWithPrefixx(OS, Name, PrefixTy, *DL, UseAt);
+  getNameWithPrefixx(OS, Name, PrefixTy, *DL, Prefix);
 
   if (!MSFunc)
     return;
 
-  // If we are supposed to add a microsoft-style suffix for stdcall/fastcall,
-  // add it.
-  // fastcall and stdcall functions usually need @42 at the end to specify
-  // the argument info.
+  // 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 ((CC == CallingConv::X86_FastCall || CC == CallingConv::X86_StdCall) &&
+  if (hasByteCountSuffix(CC) &&
       // "Pure" variadic functions do not receive @0 suffix.
       (!FT->isVarArg() || FT->getNumParams() == 0 ||
        (FT->getNumParams() == 1 && MSFunc->hasStructRetAttr())))
-    AddFastCallStdCallSuffix(OS, MSFunc, *DL);
+    addByteCountSuffix(OS, MSFunc, *DL);
 }
 
 void Mangler::getNameWithPrefix(SmallVectorImpl<char> &OutName,