Add alignment value to allowsUnalignedMemoryAccess

Rename to allowsMisalignedMemoryAccess.

On R600, 8 and 16 byte accesses are mostly OK with 4-byte alignment,
and don't need to be split into multiple accesses. Vector loads with
an alignment of the element type are not uncommon in OpenCL code.

llvm-svn: 214055
This commit is contained in:
Matt Arsenault 2014-07-27 17:46:40 +00:00
parent b3cd5a1037
commit 6f2a526101
23 changed files with 112 additions and 66 deletions

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@ -782,9 +782,10 @@ public:
/// copy/move/set is converted to a sequence of store operations. Its use
/// helps to ensure that such replacements don't generate code that causes an
/// alignment error (trap) on the target machine.
virtual bool allowsUnalignedMemoryAccesses(EVT,
unsigned AddrSpace = 0,
bool * /*Fast*/ = nullptr) const {
virtual bool allowsMisalignedMemoryAccesses(EVT,
unsigned AddrSpace = 0,
unsigned Align = 1,
bool * /*Fast*/ = nullptr) const {
return false;
}

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@ -724,10 +724,11 @@ void SelectionDAGLegalize::LegalizeStoreOps(SDNode *Node) {
// If this is an unaligned store and the target doesn't support it,
// expand it.
unsigned AS = ST->getAddressSpace();
if (!TLI.allowsUnalignedMemoryAccesses(ST->getMemoryVT(), AS)) {
unsigned Align = ST->getAlignment();
if (!TLI.allowsMisalignedMemoryAccesses(ST->getMemoryVT(), AS, Align)) {
Type *Ty = ST->getMemoryVT().getTypeForEVT(*DAG.getContext());
unsigned ABIAlignment= TLI.getDataLayout()->getABITypeAlignment(Ty);
if (ST->getAlignment() < ABIAlignment)
if (Align < ABIAlignment)
ExpandUnalignedStore(cast<StoreSDNode>(Node),
DAG, TLI, this);
}
@ -835,12 +836,13 @@ void SelectionDAGLegalize::LegalizeStoreOps(SDNode *Node) {
default: llvm_unreachable("This action is not supported yet!");
case TargetLowering::Legal: {
unsigned AS = ST->getAddressSpace();
unsigned Align = ST->getAlignment();
// If this is an unaligned store and the target doesn't support it,
// expand it.
if (!TLI.allowsUnalignedMemoryAccesses(ST->getMemoryVT(), AS)) {
if (!TLI.allowsMisalignedMemoryAccesses(ST->getMemoryVT(), AS, Align)) {
Type *Ty = ST->getMemoryVT().getTypeForEVT(*DAG.getContext());
unsigned ABIAlignment= TLI.getDataLayout()->getABITypeAlignment(Ty);
if (ST->getAlignment() < ABIAlignment)
if (Align < ABIAlignment)
ExpandUnalignedStore(cast<StoreSDNode>(Node), DAG, TLI, this);
}
break;
@ -886,13 +888,14 @@ void SelectionDAGLegalize::LegalizeLoadOps(SDNode *Node) {
default: llvm_unreachable("This action is not supported yet!");
case TargetLowering::Legal: {
unsigned AS = LD->getAddressSpace();
unsigned Align = LD->getAlignment();
// If this is an unaligned load and the target doesn't support it,
// expand it.
if (!TLI.allowsUnalignedMemoryAccesses(LD->getMemoryVT(), AS)) {
if (!TLI.allowsMisalignedMemoryAccesses(LD->getMemoryVT(), AS, Align)) {
Type *Ty = LD->getMemoryVT().getTypeForEVT(*DAG.getContext());
unsigned ABIAlignment =
TLI.getDataLayout()->getABITypeAlignment(Ty);
if (LD->getAlignment() < ABIAlignment){
if (Align < ABIAlignment){
ExpandUnalignedLoad(cast<LoadSDNode>(Node), DAG, TLI, RVal, RChain);
}
}
@ -1077,12 +1080,13 @@ void SelectionDAGLegalize::LegalizeLoadOps(SDNode *Node) {
// it, expand it.
EVT MemVT = LD->getMemoryVT();
unsigned AS = LD->getAddressSpace();
if (!TLI.allowsUnalignedMemoryAccesses(MemVT, AS)) {
unsigned Align = LD->getAlignment();
if (!TLI.allowsMisalignedMemoryAccesses(MemVT, AS, Align)) {
Type *Ty =
LD->getMemoryVT().getTypeForEVT(*DAG.getContext());
unsigned ABIAlignment =
TLI.getDataLayout()->getABITypeAlignment(Ty);
if (LD->getAlignment() < ABIAlignment){
if (Align < ABIAlignment){
ExpandUnalignedLoad(cast<LoadSDNode>(Node),
DAG, TLI, Value, Chain);
}

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@ -3810,7 +3810,7 @@ static bool FindOptimalMemOpLowering(std::vector<EVT> &MemOps,
if (VT == MVT::Other) {
unsigned AS = 0;
if (DstAlign >= TLI.getDataLayout()->getPointerPrefAlignment(AS) ||
TLI.allowsUnalignedMemoryAccesses(VT, AS)) {
TLI.allowsMisalignedMemoryAccesses(VT, AS, DstAlign)) {
VT = TLI.getPointerTy();
} else {
switch (DstAlign & 7) {
@ -3870,7 +3870,7 @@ static bool FindOptimalMemOpLowering(std::vector<EVT> &MemOps,
unsigned AS = 0;
if (NumMemOps && AllowOverlap &&
VTSize >= 8 && NewVTSize < Size &&
TLI.allowsUnalignedMemoryAccesses(VT, AS, &Fast) && Fast)
TLI.allowsMisalignedMemoryAccesses(VT, AS, DstAlign, &Fast) && Fast)
VTSize = Size;
else {
VT = NewVT;

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@ -5725,9 +5725,10 @@ bool SelectionDAGBuilder::visitMemCmpCall(const CallInst &I) {
unsigned SrcAS = RHS->getType()->getPointerAddressSpace();
// TODO: Handle 5 byte compare as 4-byte + 1 byte.
// TODO: Handle 8 byte compare on x86-32 as two 32-bit loads.
// TODO: Check alignment of src and dest ptrs.
if (!TLI->isTypeLegal(LoadVT) ||
!TLI->allowsUnalignedMemoryAccesses(LoadVT, SrcAS) ||
!TLI->allowsUnalignedMemoryAccesses(LoadVT, DstAS))
!TLI->allowsMisalignedMemoryAccesses(LoadVT, SrcAS) ||
!TLI->allowsMisalignedMemoryAccesses(LoadVT, DstAS))
ActuallyDoIt = false;
}

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@ -6229,7 +6229,7 @@ EVT AArch64TargetLowering::getOptimalMemOpType(uint64_t Size, unsigned DstAlign,
!F->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
Attribute::NoImplicitFloat) &&
(memOpAlign(SrcAlign, DstAlign, 16) ||
(allowsUnalignedMemoryAccesses(MVT::f128, 0, &Fast) && Fast)))
(allowsMisalignedMemoryAccesses(MVT::f128, 0, 1, &Fast) && Fast)))
return MVT::f128;
return Size >= 8 ? MVT::i64 : MVT::i32;

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@ -212,10 +212,11 @@ public:
MVT getScalarShiftAmountTy(EVT LHSTy) const override;
/// allowsUnalignedMemoryAccesses - Returns true if the target allows
/// allowsMisalignedMemoryAccesses - Returns true if the target allows
/// unaligned memory accesses. of the specified type.
bool allowsUnalignedMemoryAccesses(EVT VT, unsigned AddrSpace = 0,
bool *Fast = nullptr) const override {
bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AddrSpace = 0,
unsigned Align = 1,
bool *Fast = nullptr) const override {
if (RequireStrictAlign)
return false;
// FIXME: True for Cyclone, but not necessary others.

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@ -9696,8 +9696,10 @@ bool ARMTargetLowering::isDesirableToTransformToIntegerOp(unsigned Opc,
return (VT == MVT::f32) && (Opc == ISD::LOAD || Opc == ISD::STORE);
}
bool ARMTargetLowering::allowsUnalignedMemoryAccesses(EVT VT, unsigned,
bool *Fast) const {
bool ARMTargetLowering::allowsMisalignedMemoryAccesses(EVT VT,
unsigned,
unsigned,
bool *Fast) const {
// The AllowsUnaliged flag models the SCTLR.A setting in ARM cpus
bool AllowsUnaligned = Subtarget->allowsUnalignedMem();
@ -9751,11 +9753,12 @@ EVT ARMTargetLowering::getOptimalMemOpType(uint64_t Size,
bool Fast;
if (Size >= 16 &&
(memOpAlign(SrcAlign, DstAlign, 16) ||
(allowsUnalignedMemoryAccesses(MVT::v2f64, 0, &Fast) && Fast))) {
(allowsMisalignedMemoryAccesses(MVT::v2f64, 0, 1, &Fast) && Fast))) {
return MVT::v2f64;
} else if (Size >= 8 &&
(memOpAlign(SrcAlign, DstAlign, 8) ||
(allowsUnalignedMemoryAccesses(MVT::f64, 0, &Fast) && Fast))) {
(allowsMisalignedMemoryAccesses(MVT::f64, 0, 1, &Fast) &&
Fast))) {
return MVT::f64;
}
}

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@ -266,11 +266,12 @@ namespace llvm {
bool isDesirableToTransformToIntegerOp(unsigned Opc, EVT VT) const override;
/// allowsUnalignedMemoryAccesses - Returns true if the target allows
/// allowsMisalignedMemoryAccesses - Returns true if the target allows
/// unaligned memory accesses of the specified type. Returns whether it
/// is "fast" by reference in the second argument.
bool allowsUnalignedMemoryAccesses(EVT VT, unsigned AddrSpace,
bool *Fast) const override;
bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AddrSpace,
unsigned Align,
bool *Fast) const override;
EVT getOptimalMemOpType(uint64_t Size,
unsigned DstAlign, unsigned SrcAlign,

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@ -188,7 +188,7 @@ protected:
/// AllowsUnalignedMem - If true, the subtarget allows unaligned memory
/// accesses for some types. For details, see
/// ARMTargetLowering::allowsUnalignedMemoryAccesses().
/// ARMTargetLowering::allowsMisalignedMemoryAccesses().
bool AllowsUnalignedMem;
/// RestrictIT - If true, the subtarget disallows generation of deprecated IT

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@ -157,9 +157,10 @@ llvm::createMips16TargetLowering(MipsTargetMachine &TM,
}
bool
Mips16TargetLowering::allowsUnalignedMemoryAccesses(EVT VT,
unsigned,
bool *Fast) const {
Mips16TargetLowering::allowsMisalignedMemoryAccesses(EVT VT,
unsigned,
unsigned,
bool *Fast) const {
return false;
}

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@ -22,8 +22,9 @@ namespace llvm {
explicit Mips16TargetLowering(MipsTargetMachine &TM,
const MipsSubtarget &STI);
bool allowsUnalignedMemoryAccesses(EVT VT, unsigned AddrSpace,
bool *Fast) const override;
bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AddrSpace,
unsigned Align,
bool *Fast) const override;
MachineBasicBlock *
EmitInstrWithCustomInserter(MachineInstr *MI,

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@ -329,9 +329,10 @@ addMSAFloatType(MVT::SimpleValueType Ty, const TargetRegisterClass *RC) {
}
bool
MipsSETargetLowering::allowsUnalignedMemoryAccesses(EVT VT,
unsigned,
bool *Fast) const {
MipsSETargetLowering::allowsMisalignedMemoryAccesses(EVT VT,
unsigned,
unsigned,
bool *Fast) const {
MVT::SimpleValueType SVT = VT.getSimpleVT().SimpleTy;
if (Subtarget.systemSupportsUnalignedAccess()) {

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@ -31,8 +31,9 @@ namespace llvm {
void addMSAFloatType(MVT::SimpleValueType Ty,
const TargetRegisterClass *RC);
bool allowsUnalignedMemoryAccesses(EVT VT, unsigned AS = 0,
bool *Fast = nullptr) const override;
bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AS = 0,
unsigned Align = 1,
bool *Fast = nullptr) const override;
SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;

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@ -9214,9 +9214,10 @@ bool PPCTargetLowering::isLegalAddImmediate(int64_t Imm) const {
return isInt<16>(Imm) || isUInt<16>(Imm);
}
bool PPCTargetLowering::allowsUnalignedMemoryAccesses(EVT VT,
unsigned,
bool *Fast) const {
bool PPCTargetLowering::allowsMisalignedMemoryAccesses(EVT VT,
unsigned,
unsigned,
bool *Fast) const {
if (DisablePPCUnaligned)
return false;

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@ -494,9 +494,10 @@ namespace llvm {
/// Is unaligned memory access allowed for the given type, and is it fast
/// relative to software emulation.
bool allowsUnalignedMemoryAccesses(EVT VT,
unsigned AddrSpace,
bool *Fast = nullptr) const override;
bool allowsMisalignedMemoryAccesses(EVT VT,
unsigned AddrSpace,
unsigned Align = 1,
bool *Fast = nullptr) const override;
/// isFMAFasterThanFMulAndFAdd - Return true if an FMA operation is faster
/// than a pair of fmul and fadd instructions. fmuladd intrinsics will be

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@ -240,15 +240,13 @@ SITargetLowering::SITargetLowering(TargetMachine &TM) :
// TargetLowering queries
//===----------------------------------------------------------------------===//
bool SITargetLowering::allowsUnalignedMemoryAccesses(EVT VT,
unsigned AddrSpace,
bool *IsFast) const {
bool SITargetLowering::allowsMisalignedMemoryAccesses(EVT VT,
unsigned AddrSpace,
unsigned Align,
bool *IsFast) const {
if (IsFast)
*IsFast = false;
// XXX: This depends on the address space and also we may want to revist
// the alignment values we specify in the DataLayout.
// TODO: I think v3i32 should allow unaligned accesses on CI with DS_READ_B96,
// which isn't a simple VT.
if (!VT.isSimple() || VT == MVT::Other)
@ -261,8 +259,12 @@ bool SITargetLowering::allowsUnalignedMemoryAccesses(EVT VT,
// XXX - The only mention I see of this in the ISA manual is for LDS direct
// reads the "byte address and must be dword aligned". Is it also true for the
// normal loads and stores?
if (AddrSpace == AMDGPUAS::LOCAL_ADDRESS)
return false;
if (AddrSpace == AMDGPUAS::LOCAL_ADDRESS) {
// ds_read/write_b64 require 8-byte alignment, but we can do a 4 byte
// aligned, 8 byte access in a single operation using ds_read2/write2_b32
// with adjacent offsets.
return Align % 4 == 0;
}
// 8.1.6 - For Dword or larger reads or writes, the two LSBs of the
// byte-address are ignored, thus forcing Dword alignment.

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@ -59,8 +59,9 @@ class SITargetLowering : public AMDGPUTargetLowering {
public:
SITargetLowering(TargetMachine &tm);
bool allowsUnalignedMemoryAccesses(EVT VT, unsigned AS,
bool *IsFast) const override;
bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AS,
unsigned Align,
bool *IsFast) const override;
TargetLoweringBase::LegalizeTypeAction
getPreferredVectorAction(EVT VT) const override;

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@ -339,9 +339,10 @@ bool SystemZTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
return Imm.isZero() || Imm.isNegZero();
}
bool SystemZTargetLowering::allowsUnalignedMemoryAccesses(EVT VT,
unsigned,
bool *Fast) const {
bool SystemZTargetLowering::allowsMisalignedMemoryAccesses(EVT VT,
unsigned,
unsigned,
bool *Fast) const {
// Unaligned accesses should never be slower than the expanded version.
// We check specifically for aligned accesses in the few cases where
// they are required.

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@ -208,8 +208,9 @@ public:
bool isFMAFasterThanFMulAndFAdd(EVT VT) const override;
bool isFPImmLegal(const APFloat &Imm, EVT VT) const override;
bool isLegalAddressingMode(const AddrMode &AM, Type *Ty) const override;
bool allowsUnalignedMemoryAccesses(EVT VT, unsigned AS,
bool *Fast) const override;
bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AS,
unsigned Align,
bool *Fast) const override;
bool isTruncateFree(Type *, Type *) const override;
bool isTruncateFree(EVT, EVT) const override;
const char *getTargetNodeName(unsigned Opcode) const override;

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@ -1775,9 +1775,10 @@ bool X86TargetLowering::isSafeMemOpType(MVT VT) const {
}
bool
X86TargetLowering::allowsUnalignedMemoryAccesses(EVT VT,
unsigned,
bool *Fast) const {
X86TargetLowering::allowsMisalignedMemoryAccesses(EVT VT,
unsigned,
unsigned,
bool *Fast) const {
if (Fast)
*Fast = Subtarget->isUnalignedMemAccessFast();
return true;

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@ -565,10 +565,10 @@ namespace llvm {
/// legal as the hook is used before type legalization.
bool isSafeMemOpType(MVT VT) const override;
/// allowsUnalignedMemoryAccesses - Returns true if the target allows
/// allowsMisalignedMemoryAccesses - Returns true if the target allows
/// unaligned memory accesses. of the specified type. Returns whether it
/// is "fast" by reference in the second argument.
bool allowsUnalignedMemoryAccesses(EVT VT, unsigned AS,
bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AS, unsigned Align,
bool *Fast) const override;
/// LowerOperation - Provide custom lowering hooks for some operations.

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@ -426,7 +426,9 @@ LowerLOAD(SDValue Op, SelectionDAG &DAG) const {
assert(LD->getExtensionType() == ISD::NON_EXTLOAD &&
"Unexpected extension type");
assert(LD->getMemoryVT() == MVT::i32 && "Unexpected load EVT");
if (allowsUnalignedMemoryAccesses(LD->getMemoryVT()))
if (allowsMisalignedMemoryAccesses(LD->getMemoryVT(),
LD->getAddressSpace(),
LD->getAlignment()))
return SDValue();
unsigned ABIAlignment = getDataLayout()->
@ -504,7 +506,9 @@ LowerSTORE(SDValue Op, SelectionDAG &DAG) const
StoreSDNode *ST = cast<StoreSDNode>(Op);
assert(!ST->isTruncatingStore() && "Unexpected store type");
assert(ST->getMemoryVT() == MVT::i32 && "Unexpected store EVT");
if (allowsUnalignedMemoryAccesses(ST->getMemoryVT())) {
if (allowsMisalignedMemoryAccesses(ST->getMemoryVT(),
ST->getAddressSpace(),
ST->getAlignment())) {
return SDValue();
}
unsigned ABIAlignment = getDataLayout()->
@ -1803,7 +1807,9 @@ SDValue XCoreTargetLowering::PerformDAGCombine(SDNode *N,
// Replace unaligned store of unaligned load with memmove.
StoreSDNode *ST = cast<StoreSDNode>(N);
if (!DCI.isBeforeLegalize() ||
allowsUnalignedMemoryAccesses(ST->getMemoryVT()) ||
allowsMisalignedMemoryAccesses(ST->getMemoryVT(),
ST->getAddressSpace(),
ST->getAlignment()) ||
ST->isVolatile() || ST->isIndexed()) {
break;
}

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@ -31,3 +31,20 @@ define void @unaligned_load_store_v4i32(<4 x i32> addrspace(3)* %p, <4 x i32> ad
store <4 x i32> %v, <4 x i32> addrspace(3)* %r, align 1
ret void
}
; FIXME: This should use ds_read2_b32
; SI-LABEL: @load_lds_i64_align_4
; SI: DS_READ_B64
; SI: S_ENDPGM
define void @load_lds_i64_align_4(i64 addrspace(1)* nocapture %out, i64 addrspace(3)* %in) #0 {
%val = load i64 addrspace(3)* %in, align 4
store i64 %val, i64 addrspace(1)* %out, align 8
ret void
}
; FIXME: Need to fix this case.
; define void @load_lds_i64_align_1(i64 addrspace(1)* nocapture %out, i64 addrspace(3)* %in) #0 {
; %val = load i64 addrspace(3)* %in, align 1
; store i64 %val, i64 addrspace(1)* %out, align 8
; ret void
; }