Add element atomic memmove intrinsic

[dneilson]

Summary

Continuing the work from https://reviews.llvm.org/D33240, this change introduces an element unordered-atomic memmove intrinsic. This intrinsic is essentially memmove with the implementation requirement that all loads/stores used for the copy are done with unordered-atomic loads/stores of a given element size.

[reames]

LGTM. Very nice. Please wait a day or two to give others time to comment before landing though.

For those following along, the general direction of this work is described over in description of https://reviews.llvm.org/D34883. Reading through that might give useful context.

llvm/trunk/docs/LangRef.rst

 """"""""""
 
 The '``llvm.memcpy.*``' intrinsics copy a block of memory from the
 source location to the destination location, which are not allowed to
 overlap. It copies "len" bytes of memory over. If the argument is known
 to be aligned to some boundary, this can be specified as the fourth
 argument, otherwise it should be set to 0 or 1 (both meaning no alignment).
 
+.. _int_memmove:
+
 '``llvm.memmove``' Intrinsic
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Syntax:
 """""""
 
 This is an overloaded intrinsic. You can use llvm.memmove on any integer
 bit width and for different address space. Not all targets support all

 
 Lowering:
 """""""""
 
 In the most general case call to the '``llvm.memcpy.element.unordered.atomic.*``' is
 lowered to a call to the symbol ``__llvm_memcpy_element_unordered_atomic_*``. Where '*'
 is replaced with an actual element size.
 
+Optimizer is allowed to inline memory copy when it's profitable to do so.
+
+'``llvm.memmove.element.unordered.atomic``' Intrinsic
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Syntax:
+"""""""
+
+This is an overloaded intrinsic. You can use
+``llvm.memmove.element.unordered.atomic`` on any integer bit width and for
+different address spaces. Not all targets support all bit widths however.
+
+::
+
+      declare void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* <dest>,
+                                                                        i8* <src>,
+                                                                        i32 <len>,
+                                                                        i32 <element_size>)
+      declare void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i64(i8* <dest>,
+                                                                        i8* <src>,
+                                                                        i64 <len>,
+                                                                        i32 <element_size>)
+
+Overview:
+"""""""""
+
+The '``llvm.memmove.element.unordered.atomic.*``' intrinsic is a specialization
+of the '``llvm.memmove.*``' intrinsic. It differs in that the ``dest`` and
+``src`` are treated as arrays with elements that are exactly ``element_size``
+bytes, and the copy between buffers uses a sequence of
+:ref:`unordered atomic <ordering>` load/store operations that are a positive
+integer multiple of the ``element_size`` in size.
+
+Arguments:
+""""""""""
+
+The first three arguments are the same as they are in the
+:ref:`@llvm.memmove <int_memmove>` intrinsic, with the added constraint that
+``len`` is required to be a positive integer multiple of the ``element_size``.
+If ``len`` is not a positive integer multiple of ``element_size``, then the
+behaviour of the intrinsic is undefined.
+
+``element_size`` must be a compile-time constant positive power of two no
+greater than a target-specific atomic access size limit.
+
+For each of the input pointers the ``align`` parameter attribute must be
+specified. It must be a power of two no less than the ``element_size``. Caller
+guarantees that both the source and destination pointers are aligned to that
+boundary.
+
+Semantics:
+""""""""""
+
+The '``llvm.memmove.element.unordered.atomic.*``' intrinsic copies ``len`` bytes
+of memory from the source location to the destination location. These locations
+are allowed to overlap. The memory copy is performed as a sequence of load/store
+operations where each access is guaranteed to be a multiple of ``element_size``
+bytes wide and aligned at an ``element_size`` boundary. 
+
+The order of the copy is unspecified. The same value may be read from the source
+buffer many times, but only one write is issued to the destination buffer per
+element. It is well defined to have concurrent reads and writes to both source
+and destination provided those reads and writes are unordered atomic when
+specified.
+
+This intrinsic does not provide any additional ordering guarantees over those
+provided by a set of unordered loads from the source location and stores to the
+destination.
+
+Lowering:
+"""""""""
+
+In the most general case call to the
+'``llvm.memmove.element.unordered.atomic.*``' is lowered to a call to the symbol
+``__llvm_memmove_element_unordered_atomic_*``. Where '*' is replaced with an
+actual element size.
+
 The optimizer is allowed to inline the memory copy when it's profitable to do so.

llvm/trunk/include/llvm/CodeGen/RuntimeLibcalls.h

enum Libcall {
 
     // ELEMENT-WISE UNORDERED-ATOMIC MEMORY of different element sizes
     MEMCPY_ELEMENT_UNORDERED_ATOMIC_1,
     MEMCPY_ELEMENT_UNORDERED_ATOMIC_2,
     MEMCPY_ELEMENT_UNORDERED_ATOMIC_4,
     MEMCPY_ELEMENT_UNORDERED_ATOMIC_8,
     MEMCPY_ELEMENT_UNORDERED_ATOMIC_16,
 
+    MEMMOVE_ELEMENT_UNORDERED_ATOMIC_1,
+    MEMMOVE_ELEMENT_UNORDERED_ATOMIC_2,
+    MEMMOVE_ELEMENT_UNORDERED_ATOMIC_4,
+    MEMMOVE_ELEMENT_UNORDERED_ATOMIC_8,
+    MEMMOVE_ELEMENT_UNORDERED_ATOMIC_16,
+    
     // EXCEPTION HANDLING
     UNWIND_RESUME,
 
     // Note: there's two sets of atomics libcalls; see
     // <http://llvm.org/docs/Atomics.html> for more info on the
     // difference between them.
 
     // Atomic '__sync_*' libcalls.
namespace RTLIB {
   /// Return the SYNC_FETCH_AND_* value for the given opcode and type, or
   /// UNKNOWN_LIBCALL if there is none.
   Libcall getSYNC(unsigned Opc, MVT VT);
 
   /// getMEMCPY_ELEMENT_UNORDERED_ATOMIC - Return
   /// MEMCPY_ELEMENT_UNORDERED_ATOMIC_* value for the given element size or
   /// UNKNOW_LIBCALL if there is none.
   Libcall getMEMCPY_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize);
+
+  /// getMEMMOVE_ELEMENT_UNORDERED_ATOMIC - Return
+  /// MEMMOVE_ELEMENT_UNORDERED_ATOMIC_* value for the given element size or
+  /// UNKNOW_LIBCALL if there is none.
+  Libcall getMEMMOVE_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize);
 }
 }
 
 #endif

llvm/trunk/include/llvm/IR/IntrinsicInst.h

public:
     static bool classof(const IntrinsicInst *I) {
       return I->getIntrinsicID() == Intrinsic::memcpy_element_unordered_atomic;
     }
     static bool classof(const Value *V) {
       return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
     }
   };
 
+  class ElementUnorderedAtomicMemMoveInst : public IntrinsicInst {
+  private:
+    enum { ARG_DEST = 0, ARG_SOURCE = 1, ARG_LENGTH = 2, ARG_ELEMENTSIZE = 3 };
+
+  public:
+    Value *getRawDest() const {
+      return const_cast<Value *>(getArgOperand(ARG_DEST));
+    }
+    const Use &getRawDestUse() const { return getArgOperandUse(ARG_DEST); }
+    Use &getRawDestUse() { return getArgOperandUse(ARG_DEST); }
+
+    /// Return the arguments to the instruction.
+    Value *getRawSource() const {
+      return const_cast<Value *>(getArgOperand(ARG_SOURCE));
+    }
+    const Use &getRawSourceUse() const { return getArgOperandUse(ARG_SOURCE); }
+    Use &getRawSourceUse() { return getArgOperandUse(ARG_SOURCE); }
+
+    Value *getLength() const {
+      return const_cast<Value *>(getArgOperand(ARG_LENGTH));
+    }
+    const Use &getLengthUse() const { return getArgOperandUse(ARG_LENGTH); }
+    Use &getLengthUse() { return getArgOperandUse(ARG_LENGTH); }
+
+    bool isVolatile() const { return false; }
+
+    Value *getRawElementSizeInBytes() const {
+      return const_cast<Value *>(getArgOperand(ARG_ELEMENTSIZE));
+    }
+
+    ConstantInt *getElementSizeInBytesCst() const {
+      return cast<ConstantInt>(getRawElementSizeInBytes());
+    }
+
+    uint32_t getElementSizeInBytes() const {
+      return getElementSizeInBytesCst()->getZExtValue();
+    }
+
+    /// This is just like getRawDest, but it strips off any cast
+    /// instructions that feed it, giving the original input.  The returned
+    /// value is guaranteed to be a pointer.
+    Value *getDest() const { return getRawDest()->stripPointerCasts(); }
+
+    /// This is just like getRawSource, but it strips off any cast
+    /// instructions that feed it, giving the original input.  The returned
+    /// value is guaranteed to be a pointer.
+    Value *getSource() const { return getRawSource()->stripPointerCasts(); }
+
+    unsigned getDestAddressSpace() const {
+      return cast<PointerType>(getRawDest()->getType())->getAddressSpace();
+    }
+
+    unsigned getSourceAddressSpace() const {
+      return cast<PointerType>(getRawSource()->getType())->getAddressSpace();
+    }
+
+    /// Set the specified arguments of the instruction.
+    void setDest(Value *Ptr) {
+      assert(getRawDest()->getType() == Ptr->getType() &&
+             "setDest called with pointer of wrong type!");
+      setArgOperand(ARG_DEST, Ptr);
+    }
+
+    void setSource(Value *Ptr) {
+      assert(getRawSource()->getType() == Ptr->getType() &&
+             "setSource called with pointer of wrong type!");
+      setArgOperand(ARG_SOURCE, Ptr);
+    }
+
+    void setLength(Value *L) {
+      assert(getLength()->getType() == L->getType() &&
+             "setLength called with value of wrong type!");
+      setArgOperand(ARG_LENGTH, L);
+    }
+
+    void setElementSizeInBytes(Constant *V) {
+      assert(V->getType() == Type::getInt8Ty(getContext()) &&
+             "setElementSizeInBytes called with value of wrong type!");
+      setArgOperand(ARG_ELEMENTSIZE, V);
+    }
+
+    static inline bool classof(const IntrinsicInst *I) {
+      return I->getIntrinsicID() == Intrinsic::memmove_element_unordered_atomic;
+    }
+    static inline bool classof(const Value *V) {
+      return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
+    }
+  };
+
   /// This is the common base class for memset/memcpy/memmove.
   class MemIntrinsic : public IntrinsicInst {
   public:
     Value *getRawDest() const { return const_cast<Value*>(getArgOperand(0)); }
     const Use &getRawDestUse() const { return getArgOperandUse(0); }
     Use &getRawDestUse() { return getArgOperandUse(0); }
 
     Value *getLength() const { return const_cast<Value*>(getArgOperand(2)); }

llvm/trunk/include/llvm/IR/Intrinsics.td

: Intrinsic<[],
                 [
                   llvm_anyptr_ty, llvm_anyptr_ty, llvm_anyint_ty, llvm_i32_ty
                 ],
                 [
                   IntrArgMemOnly, NoCapture<0>, NoCapture<1>, WriteOnly<0>,
                   ReadOnly<1>
                 ]>;
 
+// @llvm.memmove.element.unordered.atomic.*(dest, src, length, elementsize)
+def int_memmove_element_unordered_atomic
+    : Intrinsic<[],
+                [
+                  llvm_anyptr_ty, llvm_anyptr_ty, llvm_anyint_ty, llvm_i32_ty
+                ],
+                [
+                  IntrArgMemOnly, NoCapture<0>, NoCapture<1>, WriteOnly<0>,
+                  ReadOnly<1>
+                ]>;
+
+
 //===------------------------ Reduction Intrinsics ------------------------===//
 //
 def int_experimental_vector_reduce_fadd : Intrinsic<[llvm_anyfloat_ty],
                                                     [llvm_anyfloat_ty,
                                                      llvm_anyvector_ty],
                                                     [IntrNoMem]>;
 def int_experimental_vector_reduce_fmul : Intrinsic<[llvm_anyfloat_ty],
                                                     [llvm_anyfloat_ty,

llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp

CLI.setDebugLoc(sdl).setChain(getRoot()).setLibCallee(
         DAG.getExternalSymbol(TLI.getLibcallName(LibraryCall),
                               TLI.getPointerTy(DAG.getDataLayout())),
         std::move(Args));
 
     std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
     DAG.setRoot(CallResult.second);
     return nullptr;
   }
+  case Intrinsic::memmove_element_unordered_atomic: {
+    auto &MI = cast<ElementUnorderedAtomicMemMoveInst>(I);
+    SDValue Dst = getValue(MI.getRawDest());
+    SDValue Src = getValue(MI.getRawSource());
+    SDValue Length = getValue(MI.getLength());
+
+    // Emit a library call.
+    TargetLowering::ArgListTy Args;
+    TargetLowering::ArgListEntry Entry;
+    Entry.Ty = DAG.getDataLayout().getIntPtrType(*DAG.getContext());
+    Entry.Node = Dst;
+    Args.push_back(Entry);
+
+    Entry.Node = Src;
+    Args.push_back(Entry);
+
+    Entry.Ty = MI.getLength()->getType();
+    Entry.Node = Length;
+    Args.push_back(Entry);
+
+    uint64_t ElementSizeConstant = MI.getElementSizeInBytes();
+    RTLIB::Libcall LibraryCall =
+        RTLIB::getMEMMOVE_ELEMENT_UNORDERED_ATOMIC(ElementSizeConstant);
+    if (LibraryCall == RTLIB::UNKNOWN_LIBCALL)
+      report_fatal_error("Unsupported element size");
+
+    TargetLowering::CallLoweringInfo CLI(DAG);
+    CLI.setDebugLoc(sdl).setChain(getRoot()).setLibCallee(
+        TLI.getLibcallCallingConv(LibraryCall),
+        Type::getVoidTy(*DAG.getContext()),
+        DAG.getExternalSymbol(TLI.getLibcallName(LibraryCall),
+                              TLI.getPointerTy(DAG.getDataLayout())),
+        std::move(Args));
+
+    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
+    DAG.setRoot(CallResult.second);
+    return nullptr;
+  }
   case Intrinsic::dbg_declare: {
     const DbgDeclareInst &DI = cast<DbgDeclareInst>(I);
     DILocalVariable *Variable = DI.getVariable();
     DIExpression *Expression = DI.getExpression();
     const Value *Address = DI.getAddress();
     assert(Variable && "Missing variable");
     if (!Address) {
       DEBUG(dbgs() << "Dropping debug info for " << DI << "\n");

llvm/trunk/lib/CodeGen/TargetLoweringBase.cpp

static void InitLibcallNames(const char **Names, const Triple &TT) {
   Names[RTLIB::MEMCPY_ELEMENT_UNORDERED_ATOMIC_2] =
       "__llvm_memcpy_element_unordered_atomic_2";
   Names[RTLIB::MEMCPY_ELEMENT_UNORDERED_ATOMIC_4] =
       "__llvm_memcpy_element_unordered_atomic_4";
   Names[RTLIB::MEMCPY_ELEMENT_UNORDERED_ATOMIC_8] =
       "__llvm_memcpy_element_unordered_atomic_8";
   Names[RTLIB::MEMCPY_ELEMENT_UNORDERED_ATOMIC_16] =
       "__llvm_memcpy_element_unordered_atomic_16";
+  Names[RTLIB::MEMMOVE_ELEMENT_UNORDERED_ATOMIC_1] =
+      "__llvm_memmove_element_unordered_atomic_1";
+  Names[RTLIB::MEMMOVE_ELEMENT_UNORDERED_ATOMIC_2] =
+      "__llvm_memmove_element_unordered_atomic_2";
+  Names[RTLIB::MEMMOVE_ELEMENT_UNORDERED_ATOMIC_4] =
+      "__llvm_memmove_element_unordered_atomic_4";
+  Names[RTLIB::MEMMOVE_ELEMENT_UNORDERED_ATOMIC_8] =
+      "__llvm_memmove_element_unordered_atomic_8";
+  Names[RTLIB::MEMMOVE_ELEMENT_UNORDERED_ATOMIC_16] =
+      "__llvm_memmove_element_unordered_atomic_16";
   Names[RTLIB::UNWIND_RESUME] = "_Unwind_Resume";
   Names[RTLIB::SYNC_VAL_COMPARE_AND_SWAP_1] = "__sync_val_compare_and_swap_1";
   Names[RTLIB::SYNC_VAL_COMPARE_AND_SWAP_2] = "__sync_val_compare_and_swap_2";
   Names[RTLIB::SYNC_VAL_COMPARE_AND_SWAP_4] = "__sync_val_compare_and_swap_4";
   Names[RTLIB::SYNC_VAL_COMPARE_AND_SWAP_8] = "__sync_val_compare_and_swap_8";
   Names[RTLIB::SYNC_VAL_COMPARE_AND_SWAP_16] = "__sync_val_compare_and_swap_16";
   Names[RTLIB::SYNC_LOCK_TEST_AND_SET_1] = "__sync_lock_test_and_set_1";
   Names[RTLIB::SYNC_LOCK_TEST_AND_SET_2] = "__sync_lock_test_and_set_2";
case 8:
     return MEMCPY_ELEMENT_UNORDERED_ATOMIC_8;
   case 16:
     return MEMCPY_ELEMENT_UNORDERED_ATOMIC_16;
   default:
     return UNKNOWN_LIBCALL;
   }
 }
 
+RTLIB::Libcall RTLIB::getMEMMOVE_ELEMENT_UNORDERED_ATOMIC(uint64_t ElementSize) {
+  switch (ElementSize) {
+  case 1:
+    return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_1;
+  case 2:
+    return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_2;
+  case 4:
+    return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_4;
+  case 8:
+    return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_8;
+  case 16:
+    return MEMMOVE_ELEMENT_UNORDERED_ATOMIC_16;
+  default:
+    return UNKNOWN_LIBCALL;
+  }
+}
+
 /// InitCmpLibcallCCs - Set default comparison libcall CC.
 ///
 static void InitCmpLibcallCCs(ISD::CondCode *CCs) {
   memset(CCs, ISD::SETCC_INVALID, sizeof(ISD::CondCode)*RTLIB::UNKNOWN_LIBCALL);
   CCs[RTLIB::OEQ_F32] = ISD::SETEQ;
   CCs[RTLIB::OEQ_F64] = ISD::SETEQ;
   CCs[RTLIB::OEQ_F128] = ISD::SETEQ;
   CCs[RTLIB::OEQ_PPCF128] = ISD::SETEQ;

llvm/trunk/lib/IR/Verifier.cpp

case Intrinsic::memcpy_element_unordered_atomic: {
     uint64_t DstAlignment = CS.getParamAlignment(0),
              SrcAlignment = CS.getParamAlignment(1);
     Assert(IsValidAlignment(DstAlignment),
            "incorrect alignment of the destination argument", CS);
     Assert(IsValidAlignment(SrcAlignment),
            "incorrect alignment of the source argument", CS);
     break;
   }
+  case Intrinsic::memmove_element_unordered_atomic: {
+    auto *MI = cast<ElementUnorderedAtomicMemMoveInst>(CS.getInstruction());
+
+    ConstantInt *ElementSizeCI =
+        dyn_cast<ConstantInt>(MI->getRawElementSizeInBytes());
+    Assert(ElementSizeCI,
+           "element size of the element-wise unordered atomic memory "
+           "intrinsic must be a constant int",
+           CS);
+    const APInt &ElementSizeVal = ElementSizeCI->getValue();
+    Assert(ElementSizeVal.isPowerOf2(),
+           "element size of the element-wise atomic memory intrinsic "
+           "must be a power of 2",
+           CS);
+
+    if (auto *LengthCI = dyn_cast<ConstantInt>(MI->getLength())) {
+      uint64_t Length = LengthCI->getZExtValue();
+      uint64_t ElementSize = MI->getElementSizeInBytes();
+      Assert((Length % ElementSize) == 0,
+             "constant length must be a multiple of the element size in the "
+             "element-wise atomic memory intrinsic",
+             CS);
+    }
+
+    auto IsValidAlignment = [&](uint64_t Alignment) {
+      return isPowerOf2_64(Alignment) && ElementSizeVal.ule(Alignment);
+    };
+    uint64_t DstAlignment = CS.getParamAlignment(0),
+             SrcAlignment = CS.getParamAlignment(1);
+    Assert(IsValidAlignment(DstAlignment),
+           "incorrect alignment of the destination argument", CS);
+    Assert(IsValidAlignment(SrcAlignment),
+           "incorrect alignment of the source argument", CS);
+    
+    break;
+  }
   case Intrinsic::gcroot:
   case Intrinsic::gcwrite:
   case Intrinsic::gcread:
     if (ID == Intrinsic::gcroot) {
       AllocaInst *AI =
         dyn_cast<AllocaInst>(CS.getArgOperand(0)->stripPointerCasts());
       Assert(AI, "llvm.gcroot parameter #1 must be an alloca.", CS);
       Assert(isa<Constant>(CS.getArgOperand(1)),

llvm/trunk/test/CodeGen/X86/element-wise-atomic-memory-intrinsics.ll

define void @test_memcpy_args(i8** %Storage) {
   ; 2nd arg (%rsi)
   ; CHECK-DAG: movq 8(%rdi), %rsi
   ; 3rd arg (%edx) -- length
   ; CHECK-DAG: movl $4, %edx
   ; CHECK: __llvm_memcpy_element_unordered_atomic_4
   call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %Dst, i8* align 4 %Src, i32 4, i32 4)  ret void
 }
 
+define i8* @test_memmove1(i8* %P, i8* %Q) {
+  ; CHECK: test_memmove
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* align 4 %Q, i32 1, i32 1)
+  ret i8* %P
+  ; 3rd arg (%edx) -- length
+  ; CHECK-DAG: movl $1, %edx
+  ; CHECK: __llvm_memmove_element_unordered_atomic_1
+}
+
+define i8* @test_memmove2(i8* %P, i8* %Q) {
+  ; CHECK: test_memmove2
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* align 4 %Q, i32 2, i32 2)
+  ret i8* %P
+  ; 3rd arg (%edx) -- length
+  ; CHECK-DAG: movl $2, %edx
+  ; CHECK: __llvm_memmove_element_unordered_atomic_2
+}
+
+define i8* @test_memmove4(i8* %P, i8* %Q) {
+  ; CHECK: test_memmove4
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* align 4 %Q, i32 4, i32 4)
+  ret i8* %P
+  ; 3rd arg (%edx) -- length
+  ; CHECK-DAG: movl $4, %edx
+  ; CHECK: __llvm_memmove_element_unordered_atomic_4
+}
+
+define i8* @test_memmove8(i8* %P, i8* %Q) {
+  ; CHECK: test_memmove8
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 8 %P, i8* align 8 %Q, i32 8, i32 8)
+  ret i8* %P
+  ; 3rd arg (%edx) -- length
+  ; CHECK-DAG: movl $8, %edx
+  ; CHECK: __llvm_memmove_element_unordered_atomic_8
+}
+
+define i8* @test_memmove16(i8* %P, i8* %Q) {
+  ; CHECK: test_memmove16
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 16 %P, i8* align 16 %Q, i32 16, i32 16)
+  ret i8* %P
+  ; 3rd arg (%edx) -- length
+  ; CHECK-DAG: movl $16, %edx
+  ; CHECK: __llvm_memmove_element_unordered_atomic_16
+}
+
+define void @test_memmove_args(i8** %Storage) {
+  ; CHECK: test_memmove_args
+  %Dst = load i8*, i8** %Storage
+  %Src.addr = getelementptr i8*, i8** %Storage, i64 1
+  %Src = load i8*, i8** %Src.addr
+
+  ; 1st arg (%rdi)
+  ; CHECK-DAG: movq (%rdi), [[REG1:%r.+]]
+  ; CHECK-DAG: movq [[REG1]], %rdi
+  ; 2nd arg (%rsi)
+  ; CHECK-DAG: movq 8(%rdi), %rsi
+  ; 3rd arg (%edx) -- length
+  ; CHECK-DAG: movl $4, %edx
+  ; CHECK: __llvm_memmove_element_unordered_atomic_4
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %Dst, i8* align 4 %Src, i32 4, i32 4)  ret void
+}
+
 declare void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32) nounwind
+declare void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32) nounwind

llvm/trunk/test/Verifier/element-wise-atomic-memory-intrinsics.ll

define void @test_memcpy(i8* %P, i8* %Q, i32 %A, i32 %E) {
   ; CHECK: incorrect alignment of the source argument
   call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* %Q, i32 1, i32 1)
   ; CHECK: incorrect alignment of the source argument
   call void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* align 1 %Q, i32 4, i32 4)
 
   ret void
 }
 declare void @llvm.memcpy.element.unordered.atomic.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32) nounwind
+
+define void @test_memmove(i8* %P, i8* %Q, i32 %A, i32 %E) {
+  ; CHECK: element size of the element-wise unordered atomic memory intrinsic must be a constant int
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* align 4 %Q, i32 1, i32 %E)
+  ; CHECK: element size of the element-wise atomic memory intrinsic must be a power of 2
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* align 4 %Q, i32 1, i32 3)
+
+  ; CHECK: constant length must be a multiple of the element size in the element-wise atomic memory intrinsic
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* align 4 %Q, i32 7, i32 4)
+
+  ; CHECK: incorrect alignment of the destination argument
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* %P, i8* align 4 %Q, i32 1, i32 1)
+  ; CHECK: incorrect alignment of the destination argument
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 1 %P, i8* align 4 %Q, i32 4, i32 4)
+
+  ; CHECK: incorrect alignment of the source argument
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* %Q, i32 1, i32 1)
+  ; CHECK: incorrect alignment of the source argument
+  call void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* align 4 %P, i8* align 1 %Q, i32 4, i32 4)
+
+  ret void
+}
+declare void @llvm.memmove.element.unordered.atomic.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32) nounwind
+
 ; CHECK: input module is broken!