X86: Implement the vectorcall calling convention

[rnk]

Summary

This is a Microsoft calling convention that supports both x86 and x86_64
subtargets. It passes vector and floating point arguments in XMM0-XMM5,
and passes them indirectly once they are consumed.

Homogenous vector aggregates of up to four elements can be passed in
sequential vector registers, but this part is not yet implemented in
LLVM.

On 32-bit x86, it is similar to fastcall in that it uses ecx:edx as
integer register parameters and is callee cleanup. On x86_64, it
delegates to the normal win64 calling convention.

[majnemer]

lib/IR/Mangler.cpp

121

Name.startsWith("\01")

[rnk]

Closed by commit rL220745 (authored by @rnk).

include/llvm/IR/CallingConv.h

enum {
     /// \brief The C convention as specified in the x86-64 supplement to the
     /// System V ABI, used on most non-Windows systems.
     X86_64_SysV = 78,
 
     /// \brief The C convention as implemented on Windows/x86-64. This
     /// convention differs from the more common \c X86_64_SysV convention
     /// in a number of ways, most notably in that XMM registers used to pass
     /// arguments are shadowed by GPRs, and vice versa.
-    X86_64_Win64 = 79
+    X86_64_Win64 = 79,
+
+    /// \brief MSVC calling convention that passes vectors and vector aggregates
+    /// in SSE registers.
+    X86_VectorCall = 80
   };
 } // End CallingConv namespace
 
 } // End llvm namespace
 
 #endif

lib/AsmParser/LLLexer.cpp

#define KEYWORD(STR)                                                    \
   KEYWORD(prefix);
 
   KEYWORD(ccc);
   KEYWORD(fastcc);
   KEYWORD(coldcc);
   KEYWORD(x86_stdcallcc);
   KEYWORD(x86_fastcallcc);
   KEYWORD(x86_thiscallcc);
+  KEYWORD(x86_vectorcallcc);
   KEYWORD(arm_apcscc);
   KEYWORD(arm_aapcscc);
   KEYWORD(arm_aapcs_vfpcc);
   KEYWORD(msp430_intrcc);
   KEYWORD(ptx_kernel);
   KEYWORD(ptx_device);
   KEYWORD(spir_kernel);
   KEYWORD(spir_func);

lib/AsmParser/LLParser.cpp

 ///   ::= /*empty*/
 ///   ::= 'ccc'
 ///   ::= 'fastcc'
 ///   ::= 'kw_intel_ocl_bicc'
 ///   ::= 'coldcc'
 ///   ::= 'x86_stdcallcc'
 ///   ::= 'x86_fastcallcc'
 ///   ::= 'x86_thiscallcc'
+///   ::= 'x86_vectorcallcc'
 ///   ::= 'arm_apcscc'
 ///   ::= 'arm_aapcscc'
 ///   ::= 'arm_aapcs_vfpcc'
 ///   ::= 'msp430_intrcc'
 ///   ::= 'ptx_kernel'
 ///   ::= 'ptx_device'
 ///   ::= 'spir_func'
 ///   ::= 'spir_kernel'
bool LLParser::ParseOptionalCallingConv(unsigned &CC) {
   switch (Lex.getKind()) {
   default:                       CC = CallingConv::C; return false;
   case lltok::kw_ccc:            CC = CallingConv::C; break;
   case lltok::kw_fastcc:         CC = CallingConv::Fast; break;
   case lltok::kw_coldcc:         CC = CallingConv::Cold; break;
   case lltok::kw_x86_stdcallcc:  CC = CallingConv::X86_StdCall; break;
   case lltok::kw_x86_fastcallcc: CC = CallingConv::X86_FastCall; break;
   case lltok::kw_x86_thiscallcc: CC = CallingConv::X86_ThisCall; break;
+  case lltok::kw_x86_vectorcallcc:CC = CallingConv::X86_VectorCall; break;
   case lltok::kw_arm_apcscc:     CC = CallingConv::ARM_APCS; break;
   case lltok::kw_arm_aapcscc:    CC = CallingConv::ARM_AAPCS; break;
   case lltok::kw_arm_aapcs_vfpcc:CC = CallingConv::ARM_AAPCS_VFP; break;
   case lltok::kw_msp430_intrcc:  CC = CallingConv::MSP430_INTR; break;
   case lltok::kw_ptx_kernel:     CC = CallingConv::PTX_Kernel; break;
   case lltok::kw_ptx_device:     CC = CallingConv::PTX_Device; break;
   case lltok::kw_spir_kernel:    CC = CallingConv::SPIR_KERNEL; break;
   case lltok::kw_spir_func:      CC = CallingConv::SPIR_FUNC; break;

lib/AsmParser/LLToken.h

enum Kind {
     kw_alignstack,
     kw_inteldialect,
     kw_gc,
     kw_prefix,
     kw_c,
 
     kw_cc, kw_ccc, kw_fastcc, kw_coldcc,
     kw_intel_ocl_bicc,
-    kw_x86_stdcallcc, kw_x86_fastcallcc, kw_x86_thiscallcc,
+    kw_x86_stdcallcc, kw_x86_fastcallcc, kw_x86_thiscallcc, kw_x86_vectorcallcc,
     kw_arm_apcscc, kw_arm_aapcscc, kw_arm_aapcs_vfpcc,
     kw_msp430_intrcc,
     kw_ptx_kernel, kw_ptx_device,
     kw_spir_kernel, kw_spir_func,
     kw_x86_64_sysvcc, kw_x86_64_win64cc,
     kw_webkit_jscc, kw_anyregcc,
     kw_preserve_mostcc, kw_preserve_allcc,
 

lib/IR/AsmWriter.cpp

static void PrintCallingConv(unsigned cc, raw_ostream &Out) {
   case CallingConv::Cold:          Out << "coldcc"; break;
   case CallingConv::WebKit_JS:     Out << "webkit_jscc"; break;
   case CallingConv::AnyReg:        Out << "anyregcc"; break;
   case CallingConv::PreserveMost:  Out << "preserve_mostcc"; break;
   case CallingConv::PreserveAll:   Out << "preserve_allcc"; break;
   case CallingConv::X86_StdCall:   Out << "x86_stdcallcc"; break;
   case CallingConv::X86_FastCall:  Out << "x86_fastcallcc"; break;
   case CallingConv::X86_ThisCall:  Out << "x86_thiscallcc"; break;
+  case CallingConv::X86_VectorCall:Out << "x86_vectorcallcc"; break;
   case CallingConv::Intel_OCL_BI:  Out << "intel_ocl_bicc"; break;
   case CallingConv::ARM_APCS:      Out << "arm_apcscc"; break;
   case CallingConv::ARM_AAPCS:     Out << "arm_aapcscc"; break;
   case CallingConv::ARM_AAPCS_VFP: Out << "arm_aapcs_vfpcc"; break;
   case CallingConv::MSP430_INTR:   Out << "msp430_intrcc"; break;
   case CallingConv::PTX_Kernel:    Out << "ptx_kernel"; break;
   case CallingConv::PTX_Device:    Out << "ptx_device"; break;
   case CallingConv::X86_64_SysV:   Out << "x86_64_sysvcc"; break;

lib/IR/Mangler.cpp

 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Function.h"
 #include "llvm/Support/raw_ostream.h"
 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 this is a simple string that doesn't need escaping, just append it.
   OS << Name;
 }
 
 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,
                                 const Twine &GVName,
                                 ManglerPrefixTy PrefixTy) const {
   raw_svector_ostream OS(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,
   // 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 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;
 }
 
 void Mangler::getNameWithPrefix(raw_ostream &OS, const GlobalValue *GV,
                                 bool CannotUsePrivateLabel) const {
   ManglerPrefixTy PrefixTy = Mangler::Default;
if (ID == 0)
       ID = NextAnonGlobalID++;
 
     // Must mangle the global into a unique ID.
     getNameWithPrefix(OS, "__unnamed_" + Twine(ID), PrefixTy);
     return;
   }
 
   StringRef Name = GV->getName();
+  char Prefix = DL->getGlobalPrefix();
 
-  bool UseAt = false;
-  const Function *MSFunc = nullptr;
-  CallingConv::ID CC;
-  if (Name[0] != '\1' && 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;
-    }
+  // 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.empty() && Name[0] == '\01')
+    MSFunc = nullptr; // Don't mangle when \01 is present.
+  CallingConv::ID CC = MSFunc ? MSFunc->getCallingConv() : CallingConv::C;
+  if (!DL->hasMicrosoftFastStdCallMangling() &&
+      CC != CallingConv::X86_VectorCall)
+    MSFunc = nullptr;
+  if (MSFunc) {
+      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,
                                 const GlobalValue *GV,
                                 bool CannotUsePrivateLabel) const {
   raw_svector_ostream OS(OutName);
   getNameWithPrefix(OS, GV, CannotUsePrivateLabel);
 }

lib/Target/X86/X86CallingConv.h

 #ifndef LLVM_LIB_TARGET_X86_X86CALLINGCONV_H
 #define LLVM_LIB_TARGET_X86_X86CALLINGCONV_H
 
 #include "llvm/CodeGen/CallingConvLower.h"
 #include "llvm/IR/CallingConv.h"
 
 namespace llvm {
 
+inline bool CC_X86_32_VectorCallIndirect(unsigned &ValNo, MVT &ValVT,
+                                         MVT &LocVT,
+                                         CCValAssign::LocInfo &LocInfo,
+                                         ISD::ArgFlagsTy &ArgFlags,
+                                         CCState &State) {
+  // Similar to CCPassIndirect, with the addition of inreg.
+  LocVT = MVT::i32;
+  LocInfo = CCValAssign::Indirect;
+  ArgFlags.setInReg();
+  return false; // Continue the search, but now for i32.
+}
+
+
 inline bool CC_X86_AnyReg_Error(unsigned &, MVT &, MVT &,
                                 CCValAssign::LocInfo &, ISD::ArgFlagsTy &,
                                 CCState &) {
   llvm_unreachable("The AnyReg calling convention is only supported by the " \
                    "stackmap and patchpoint intrinsics.");
   // gracefully fallback to X86 C calling convention on Release builds.
   return false;
 }
 
 } // End llvm namespace
 
 #endif
 

lib/Target/X86/X86CallingConv.td

 def RetCC_X86_32_HiPE : CallingConv<[
   // Promote all types to i32
   CCIfType<[i8, i16], CCPromoteToType<i32>>,
 
   // Return: HP, P, VAL1, VAL2
   CCIfType<[i32], CCAssignToReg<[ESI, EBP, EAX, EDX]>>
 ]>;
 
+// X86-32 HiPE return-value convention.
+def RetCC_X86_32_VectorCall : CallingConv<[
+  // Vector types are returned in XMM0,XMM1,XMMM2 and XMM3.
+  CCIfType<[f32, f64, v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
+            CCAssignToReg<[XMM0,XMM1,XMM2,XMM3]>>,
+
+  // 256-bit FP vectors
+  CCIfType<[v32i8, v16i16, v8i32, v4i64, v8f32, v4f64],
+            CCAssignToReg<[YMM0,YMM1,YMM2,YMM3]>>,
+
+  // 512-bit FP vectors
+  CCIfType<[v64i8, v32i16, v16i32, v8i64, v16f32, v8f64],
+            CCAssignToReg<[ZMM0,ZMM1,ZMM2,ZMM3]>>,
+
+  // Return integers in the standard way.
+  CCDelegateTo<RetCC_X86Common>
+]>;
+
 // X86-64 C return-value convention.
 def RetCC_X86_64_C : CallingConv<[
   // The X86-64 calling convention always returns FP values in XMM0.
   CCIfType<[f32], CCAssignToReg<[XMM0, XMM1]>>,
   CCIfType<[f64], CCAssignToReg<[XMM0, XMM1]>>,
 
   // MMX vector types are always returned in XMM0.
   CCIfType<[x86mmx], CCAssignToReg<[XMM0, XMM1]>>,

 ]>;
 
 // This is the root return-value convention for the X86-32 backend.
 def RetCC_X86_32 : CallingConv<[
   // If FastCC, use RetCC_X86_32_Fast.
   CCIfCC<"CallingConv::Fast", CCDelegateTo<RetCC_X86_32_Fast>>,
   // If HiPE, use RetCC_X86_32_HiPE.
   CCIfCC<"CallingConv::HiPE", CCDelegateTo<RetCC_X86_32_HiPE>>,
+  CCIfCC<"CallingConv::X86_VectorCall", CCDelegateTo<RetCC_X86_32_VectorCall>>,
 
   // Otherwise, use RetCC_X86_32_C.
   CCDelegateTo<RetCC_X86_32_C>
 ]>;
 
 // This is the root return-value convention for the X86-64 backend.
 def RetCC_X86_64 : CallingConv<[
   // HiPE uses RetCC_X86_64_HiPE
def CC_X86_Win64_C : CallingConv<[
   // 8-byte aligned if there are no more registers to hold them.
   CCIfType<[i32, i64, f32, f64], CCAssignToStack<8, 8>>,
 
   // Long doubles get stack slots whose size and alignment depends on the
   // subtarget.
   CCIfType<[f80], CCAssignToStack<0, 0>>
 ]>;
 
+def CC_X86_Win64_VectorCall : CallingConv<[
+  // The first 6 floating point and vector types of 128 bits or less use
+  // XMM0-XMM5.
+  CCIfType<[f32, f64, v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
+           CCAssignToReg<[XMM0, XMM1, XMM2, XMM3, XMM4, XMM5]>>,
+
+  // 256-bit vectors use YMM registers.
+  CCIfType<[v32i8, v16i16, v8i32, v4i64, v8f32, v4f64],
+           CCAssignToReg<[YMM0, YMM1, YMM2, YMM3, YMM4, YMM5]>>,
+
+  // 512-bit vectors use ZMM registers.
+  CCIfType<[v64i8, v32i16, v16i32, v8i64, v16f32, v8f64],
+           CCAssignToReg<[ZMM0, ZMM1, ZMM2, ZMM3, ZMM4, ZMM5]>>,
+
+  // Delegate to fastcall to handle integer types.
+  CCDelegateTo<CC_X86_Win64_C>
+]>;
+
+
 def CC_X86_64_GHC : CallingConv<[
   // Promote i8/i16/i32 arguments to i64.
   CCIfType<[i8, i16, i32], CCPromoteToType<i64>>,
 
   // Pass in STG registers: Base, Sp, Hp, R1, R2, R3, R4, R5, R6, SpLim
   CCIfType<[i64],
             CCAssignToReg<[R13, RBP, R12, RBX, R14, RSI, RDI, R8, R9, R15]>>,
 
def CC_X86_32_FastCall : CallingConv<[
 
   // The first 2 integer arguments are passed in ECX/EDX
   CCIfInReg<CCIfType<[i32], CCAssignToReg<[ECX, EDX]>>>,
 
   // Otherwise, same as everything else.
   CCDelegateTo<CC_X86_32_Common>
 ]>;
 
+def CC_X86_32_VectorCall : CallingConv<[
+  // The first 6 floating point and vector types of 128 bits or less use
+  // XMM0-XMM5.
+  CCIfType<[f32, f64, v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
+           CCAssignToReg<[XMM0, XMM1, XMM2, XMM3, XMM4, XMM5]>>,
+
+  // 256-bit vectors use YMM registers.
+  CCIfType<[v32i8, v16i16, v8i32, v4i64, v8f32, v4f64],
+           CCAssignToReg<[YMM0, YMM1, YMM2, YMM3, YMM4, YMM5]>>,
+
+  // 512-bit vectors use ZMM registers.
+  CCIfType<[v64i8, v32i16, v16i32, v8i64, v16f32, v8f64],
+           CCAssignToReg<[ZMM0, ZMM1, ZMM2, ZMM3, ZMM4, ZMM5]>>,
+
+  // Otherwise, pass it indirectly.
+  CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64,
+            v32i8, v16i16, v8i32, v4i64, v8f32, v4f64,
+            v64i8, v32i16, v16i32, v8i64, v16f32, v8f64],
+           CCCustom<"CC_X86_32_VectorCallIndirect">>,
+
+  // Delegate to fastcall to handle integer types.
+  CCDelegateTo<CC_X86_32_FastCall>
+]>;
+
 def CC_X86_32_ThisCall_Common : CallingConv<[
   // The first integer argument is passed in ECX
   CCIfType<[i32], CCAssignToReg<[ECX]>>,
 
   // Otherwise, same as everything else.
   CCDelegateTo<CC_X86_32_Common>
 ]>;
 

 
 //===----------------------------------------------------------------------===//
 // X86 Root Argument Calling Conventions
 //===----------------------------------------------------------------------===//
 
 // This is the root argument convention for the X86-32 backend.
 def CC_X86_32 : CallingConv<[
   CCIfCC<"CallingConv::X86_FastCall", CCDelegateTo<CC_X86_32_FastCall>>,
+  CCIfCC<"CallingConv::X86_VectorCall", CCDelegateTo<CC_X86_32_VectorCall>>,
   CCIfCC<"CallingConv::X86_ThisCall", CCDelegateTo<CC_X86_32_ThisCall>>,
   CCIfCC<"CallingConv::Fast", CCDelegateTo<CC_X86_32_FastCC>>,
   CCIfCC<"CallingConv::GHC", CCDelegateTo<CC_X86_32_GHC>>,
   CCIfCC<"CallingConv::HiPE", CCDelegateTo<CC_X86_32_HiPE>>,
 
   // Otherwise, drop to normal X86-32 CC
   CCDelegateTo<CC_X86_32_C>
 ]>;
 
 // This is the root argument convention for the X86-64 backend.
 def CC_X86_64 : CallingConv<[
   CCIfCC<"CallingConv::GHC", CCDelegateTo<CC_X86_64_GHC>>,
   CCIfCC<"CallingConv::HiPE", CCDelegateTo<CC_X86_64_HiPE>>,
   CCIfCC<"CallingConv::WebKit_JS", CCDelegateTo<CC_X86_64_WebKit_JS>>,
   CCIfCC<"CallingConv::AnyReg", CCDelegateTo<CC_X86_64_AnyReg>>,
   CCIfCC<"CallingConv::X86_64_Win64", CCDelegateTo<CC_X86_Win64_C>>,
   CCIfCC<"CallingConv::X86_64_SysV", CCDelegateTo<CC_X86_64_C>>,
+  CCIfCC<"CallingConv::X86_VectorCall", CCDelegateTo<CC_X86_Win64_VectorCall>>,
 
   // Mingw64 and native Win64 use Win64 CC
   CCIfSubtarget<"isTargetWin64()", CCDelegateTo<CC_X86_Win64_C>>,
 
   // Otherwise, drop to normal X86-64 CC
   CCDelegateTo<CC_X86_64_C>
 ]>;
 

test/CodeGen/X86/vectorcall.ll

+; RUN: llc -mtriple=i686-pc-win32 -mattr=+sse2 < %s | FileCheck %s --check-prefix=CHECK --check-prefix=X86
+; RUN: llc -mtriple=x86_64-pc-win32 < %s | FileCheck %s --check-prefix=CHECK --check-prefix=X64
+
+; Test integer arguments.
+
+define x86_vectorcallcc i32 @test_int_1() {
+  ret i32 0
+}
+
+; CHECK-LABEL: {{^}}test_int_1@@0:
+; CHECK: xorl %eax, %eax
+
+define x86_vectorcallcc i32 @test_int_2(i32 inreg %a) {
+  ret i32 %a
+}
+
+; X86-LABEL: {{^}}test_int_2@@4:
+; X64-LABEL: {{^}}test_int_2@@8:
+; CHECK: movl %ecx, %eax
+
+define x86_vectorcallcc i32 @test_int_3(i64 inreg %a) {
+  %at = trunc i64 %a to i32
+  ret i32 %at
+}
+
+; X86-LABEL: {{^}}test_int_3@@8:
+; X64-LABEL: {{^}}test_int_3@@8:
+; CHECK: movl %ecx, %eax
+
+define x86_vectorcallcc i32 @test_int_4(i32 inreg %a, i32 inreg %b) {
+  %s = add i32 %a, %b
+  ret i32 %s
+}
+
+; X86-LABEL: {{^}}test_int_4@@8:
+; X86: leal (%ecx,%edx), %eax
+
+; X64-LABEL: {{^}}test_int_4@@16:
+; X64: leal (%rcx,%rdx), %eax
+
+define x86_vectorcallcc i32 @"\01test_int_5"(i32, i32) {
+  ret i32 0
+}
+; CHECK-LABEL: {{^}}test_int_5:
+
+define x86_vectorcallcc double @test_fp_1(double %a, double %b) {
+  ret double %b
+}
+; CHECK-LABEL: {{^}}test_fp_1@@16:
+; CHECK: movaps %xmm1, %xmm0
+
+define x86_vectorcallcc double @test_fp_2(
+    double, double, double, double, double, double, double %r) {
+  ret double %r
+}
+; CHECK-LABEL: {{^}}test_fp_2@@56:
+; CHECK: movsd {{[0-9]+\(%[re]sp\)}}, %xmm0
+
+define x86_vectorcallcc {double, double, double, double} @test_fp_3() {
+  ret {double, double, double, double}
+        { double 0.0, double 0.0, double 0.0, double 0.0 }
+}
+; CHECK-LABEL: {{^}}test_fp_3@@0:
+; CHECK: xorps %xmm0
+; CHECK: xorps %xmm1
+; CHECK: xorps %xmm2
+; CHECK: xorps %xmm3
+
+; FIXME: What should LLVM do with things like this that are too big?
+define x86_vectorcallcc {double, double, double, double, double} @test_fp_4() {
+  ret {double, double, double, double, double}
+        { double 0.0, double 0.0, double 0.0, double 0.0, double 0.0 }
+}
+; CHECK-LABEL: {{^}}test_fp_4@@0:
+; CHECK: xorps %xmm0
+; CHECK: xorps %xmm1
+; CHECK: xorps %xmm2
+; CHECK: xorps %xmm3
+
+define x86_vectorcallcc <16 x i8> @test_vec_1(<16 x i8> %a, <16 x i8> %b) {
+  ret <16 x i8> %b
+}
+; CHECK-LABEL: {{^}}test_vec_1@@32:
+; CHECK: movaps %xmm1, %xmm0
+
+define x86_vectorcallcc <16 x i8> @test_vec_2(
+    double, <16 x i8>, <16 x i8>, <16 x i8>, <16 x i8>, <16 x i8>, <16 x i8> %r) {
+  ret <16 x i8> %r
+}
+; CHECK-LABEL: {{^}}test_vec_2@@104:
+; CHECK: movaps (%{{[re]}}cx), %xmm0