[ARM] Use AEABI aligned function variants

AEABI defines aligned variants of memcpy etc. that can be faster than
the default version due to not having to do alignment checks. When
emitting target code for these functions make use of these aligned
variants if possible. Also convert memset to memclr if possible.

Differential Revision: http://reviews.llvm.org/D8060

llvm-svn: 237127
This commit is contained in:
John Brawn 2015-05-12 13:13:38 +00:00
parent 87ef5eaf46
commit 70605f7d22
3 changed files with 223 additions and 82 deletions

View File

@ -24,6 +24,114 @@ ARMSelectionDAGInfo::ARMSelectionDAGInfo(const DataLayout &DL)
ARMSelectionDAGInfo::~ARMSelectionDAGInfo() {
}
// Emit, if possible, a specialized version of the given Libcall. Typically this
// means selecting the appropriately aligned version, but we also convert memset
// of 0 into memclr.
SDValue ARMSelectionDAGInfo::
EmitSpecializedLibcall(SelectionDAG &DAG, SDLoc dl,
SDValue Chain,
SDValue Dst, SDValue Src,
SDValue Size, unsigned Align,
RTLIB::Libcall LC) const {
const ARMSubtarget &Subtarget =
DAG.getMachineFunction().getSubtarget<ARMSubtarget>();
const ARMTargetLowering *TLI = Subtarget.getTargetLowering();
// Only use a specialized AEABI function if the default version of this
// Libcall is an AEABI function.
if (std::strncmp(TLI->getLibcallName(LC), "__aeabi", 7) != 0)
return SDValue();
// Translate RTLIB::Libcall to AEABILibcall. We only do this in order to be
// able to translate memset to memclr and use the value to index the function
// name array.
enum {
AEABI_MEMCPY = 0,
AEABI_MEMMOVE,
AEABI_MEMSET,
AEABI_MEMCLR
} AEABILibcall;
switch (LC) {
case RTLIB::MEMCPY:
AEABILibcall = AEABI_MEMCPY;
break;
case RTLIB::MEMMOVE:
AEABILibcall = AEABI_MEMMOVE;
break;
case RTLIB::MEMSET:
AEABILibcall = AEABI_MEMSET;
if (ConstantSDNode *ConstantSrc = dyn_cast<ConstantSDNode>(Src))
if (ConstantSrc->getZExtValue() == 0)
AEABILibcall = AEABI_MEMCLR;
break;
default:
return SDValue();
}
// Choose the most-aligned libcall variant that we can
enum {
ALIGN1 = 0,
ALIGN4,
ALIGN8
} AlignVariant;
if ((Align & 7) == 0)
AlignVariant = ALIGN8;
else if ((Align & 3) == 0)
AlignVariant = ALIGN4;
else
AlignVariant = ALIGN1;
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Entry.Ty = TLI->getDataLayout()->getIntPtrType(*DAG.getContext());
Entry.Node = Dst;
Args.push_back(Entry);
if (AEABILibcall == AEABI_MEMCLR) {
Entry.Node = Size;
Args.push_back(Entry);
} else if (AEABILibcall == AEABI_MEMSET) {
// Adjust parameters for memset, EABI uses format (ptr, size, value),
// GNU library uses (ptr, value, size)
// See RTABI section 4.3.4
Entry.Node = Size;
Args.push_back(Entry);
// Extend or truncate the argument to be an i32 value for the call.
if (Src.getValueType().bitsGT(MVT::i32))
Src = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Src);
else if (Src.getValueType().bitsLT(MVT::i32))
Src = DAG.getNode(ISD::ZERO_EXTEND, dl, MVT::i32, Src);
Entry.Node = Src;
Entry.Ty = Type::getInt32Ty(*DAG.getContext());
Entry.isSExt = false;
Args.push_back(Entry);
} else {
Entry.Node = Src;
Args.push_back(Entry);
Entry.Node = Size;
Args.push_back(Entry);
}
char const *FunctionNames[4][3] = {
{ "__aeabi_memcpy", "__aeabi_memcpy4", "__aeabi_memcpy8" },
{ "__aeabi_memmove", "__aeabi_memmove4", "__aeabi_memmove8" },
{ "__aeabi_memset", "__aeabi_memset4", "__aeabi_memset8" },
{ "__aeabi_memclr", "__aeabi_memclr4", "__aeabi_memclr8" }
};
TargetLowering::CallLoweringInfo CLI(DAG);
CLI.setDebugLoc(dl).setChain(Chain)
.setCallee(TLI->getLibcallCallingConv(LC),
Type::getVoidTy(*DAG.getContext()),
DAG.getExternalSymbol(FunctionNames[AEABILibcall][AlignVariant],
TLI->getPointerTy()), std::move(Args), 0)
.setDiscardResult();
std::pair<SDValue,SDValue> CallResult = TLI->LowerCallTo(CLI);
return CallResult.second;
}
SDValue
ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl,
SDValue Chain,
@ -42,10 +150,12 @@ ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl,
// within a subtarget-specific limit.
ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Size);
if (!ConstantSize)
return SDValue();
return EmitSpecializedLibcall(DAG, dl, Chain, Dst, Src, Size, Align,
RTLIB::MEMCPY);
uint64_t SizeVal = ConstantSize->getZExtValue();
if (!AlwaysInline && SizeVal > Subtarget.getMaxInlineSizeThreshold())
return SDValue();
return EmitSpecializedLibcall(DAG, dl, Chain, Dst, Src, Size, Align,
RTLIB::MEMCPY);
unsigned BytesLeft = SizeVal & 3;
unsigned NumMemOps = SizeVal >> 2;
@ -142,59 +252,26 @@ ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl,
makeArrayRef(TFOps, i));
}
// Adjust parameters for memset, EABI uses format (ptr, size, value),
// GNU library uses (ptr, value, size)
// See RTABI section 4.3.4
SDValue ARMSelectionDAGInfo::
EmitTargetCodeForMemmove(SelectionDAG &DAG, SDLoc dl,
SDValue Chain,
SDValue Dst, SDValue Src,
SDValue Size, unsigned Align,
bool isVolatile,
MachinePointerInfo DstPtrInfo,
MachinePointerInfo SrcPtrInfo) const {
return EmitSpecializedLibcall(DAG, dl, Chain, Dst, Src, Size, Align,
RTLIB::MEMMOVE);
}
SDValue ARMSelectionDAGInfo::
EmitTargetCodeForMemset(SelectionDAG &DAG, SDLoc dl,
SDValue Chain, SDValue Dst,
SDValue Src, SDValue Size,
unsigned Align, bool isVolatile,
MachinePointerInfo DstPtrInfo) const {
const ARMSubtarget &Subtarget =
DAG.getMachineFunction().getSubtarget<ARMSubtarget>();
// Use default for non-AAPCS (or MachO) subtargets
if (!Subtarget.isAAPCS_ABI() || Subtarget.isTargetMachO() ||
Subtarget.isTargetWindows())
return SDValue();
const ARMTargetLowering &TLI = *Subtarget.getTargetLowering();
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
// First argument: data pointer
Type *IntPtrTy = TLI.getDataLayout()->getIntPtrType(*DAG.getContext());
Entry.Node = Dst;
Entry.Ty = IntPtrTy;
Args.push_back(Entry);
// Second argument: buffer size
Entry.Node = Size;
Entry.Ty = IntPtrTy;
Entry.isSExt = false;
Args.push_back(Entry);
// Extend or truncate the argument to be an i32 value for the call.
if (Src.getValueType().bitsGT(MVT::i32))
Src = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Src);
else
Src = DAG.getNode(ISD::ZERO_EXTEND, dl, MVT::i32, Src);
// Third argument: value to fill
Entry.Node = Src;
Entry.Ty = Type::getInt32Ty(*DAG.getContext());
Entry.isSExt = true;
Args.push_back(Entry);
// Emit __eabi_memset call
TargetLowering::CallLoweringInfo CLI(DAG);
CLI.setDebugLoc(dl).setChain(Chain)
.setCallee(TLI.getLibcallCallingConv(RTLIB::MEMSET),
Type::getVoidTy(*DAG.getContext()),
DAG.getExternalSymbol(TLI.getLibcallName(RTLIB::MEMSET),
TLI.getPointerTy()), std::move(Args), 0)
.setDiscardResult();
std::pair<SDValue,SDValue> CallResult = TLI.LowerCallTo(CLI);
return CallResult.second;
return EmitSpecializedLibcall(DAG, dl, Chain, Dst, Src, Size, Align,
RTLIB::MEMSET);
}

View File

@ -48,6 +48,13 @@ public:
MachinePointerInfo DstPtrInfo,
MachinePointerInfo SrcPtrInfo) const override;
SDValue EmitTargetCodeForMemmove(SelectionDAG &DAG, SDLoc dl,
SDValue Chain,
SDValue Dst, SDValue Src,
SDValue Size, unsigned Align, bool isVolatile,
MachinePointerInfo DstPtrInfo,
MachinePointerInfo SrcPtrInfo) const override;
// Adjust parameters for memset, see RTABI section 4.3.4
SDValue EmitTargetCodeForMemset(SelectionDAG &DAG, SDLoc dl,
SDValue Chain,
@ -55,6 +62,12 @@ public:
SDValue Op3, unsigned Align,
bool isVolatile,
MachinePointerInfo DstPtrInfo) const override;
SDValue EmitSpecializedLibcall(SelectionDAG &DAG, SDLoc dl,
SDValue Chain,
SDValue Dst, SDValue Src,
SDValue Size, unsigned Align,
RTLIB::Libcall LC) const;
};
}

View File

@ -18,13 +18,64 @@ entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 0, i1 false)
; EABI memset swaps arguments
; CHECK-IOS: mov r1, #1
; CHECK-IOS: memset
; CHECK-DARWIN: movs r1, #1
; CHECK-DARWIN: memset
; CHECK-EABI: mov r2, #1
; CHECK-EABI: __aeabi_memset
call void @llvm.memset.p0i8.i32(i8* %dest, i8 1, i32 500, i32 0, i1 false)
; EABI uses memclr if value set to 0
; CHECK-IOS: mov r1, #0
; CHECK-IOS: memset
; CHECK-DARWIN: movs r1, #0
; CHECK-DARWIN: memset
; CHECK-EABI: mov r2, #0
; CHECK-EABI: __aeabi_memset
; CHECK-EABI: __aeabi_memclr
call void @llvm.memset.p0i8.i32(i8* %dest, i8 0, i32 500, i32 0, i1 false)
; EABI uses aligned function variants if possible
; CHECK-IOS: memmove
; CHECK-DARWIN: memmove
; CHECK-EABI: __aeabi_memmove4
call void @llvm.memmove.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 4, i1 false)
; CHECK-IOS: memcpy
; CHECK-DARWIN: memcpy
; CHECK-EABI: __aeabi_memcpy4
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 4, i1 false)
; CHECK-IOS: memset
; CHECK-DARWIN: memset
; CHECK-EABI: __aeabi_memset4
call void @llvm.memset.p0i8.i32(i8* %dest, i8 1, i32 500, i32 4, i1 false)
; CHECK-IOS: memset
; CHECK-DARWIN: memset
; CHECK-EABI: __aeabi_memclr4
call void @llvm.memset.p0i8.i32(i8* %dest, i8 0, i32 500, i32 4, i1 false)
; CHECK-IOS: memmove
; CHECK-DARWIN: memmove
; CHECK-EABI: __aeabi_memmove8
call void @llvm.memmove.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
; CHECK-IOS: memcpy
; CHECK-DARWIN: memcpy
; CHECK-EABI: __aeabi_memcpy8
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
; CHECK-IOS: memset
; CHECK-DARWIN: memset
; CHECK-EABI: __aeabi_memset8
call void @llvm.memset.p0i8.i32(i8* %dest, i8 1, i32 500, i32 8, i1 false)
; CHECK-IOS: memset
; CHECK-DARWIN: memset
; CHECK-EABI: __aeabi_memclr8
call void @llvm.memset.p0i8.i32(i8* %dest, i8 0, i32 500, i32 8, i1 false)
unreachable
}
@ -53,17 +104,17 @@ entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %1, i32 %n, i32 0, i1 false)
; CHECK-IOS: mov r0, sp
; CHECK-IOS: mov r1, #0
; CHECK-IOS: mov r1, #1
; CHECK-IOS: memset
; CHECK-DARINW: add r0, sp, #4
; CHECK-DARWIN: movs r1, #0
; CHECK-DARWIN: add r0, sp, #4
; CHECK-DARWIN: movs r1, #1
; CHECK-DARWIN: memset
; CHECK-EABI: add r0, sp, #4
; CHECK-EABI: mov r2, #0
; CHECK-EABI: mov r2, #1
; CHECK-EABI: __aeabi_memset
%arr2 = alloca [9 x i8], align 1
%2 = bitcast [9 x i8]* %arr2 to i8*
call void @llvm.memset.p0i8.i32(i8* %2, i8 0, i32 %n, i32 0, i1 false)
call void @llvm.memset.p0i8.i32(i8* %2, i8 1, i32 %n, i32 0, i1 false)
unreachable
}
@ -90,15 +141,15 @@ entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %1, i32 %n, i32 0, i1 false)
; CHECK: {{add(.w)? r0, sp, #3}}
; CHECK-IOS: mov r1, #0
; CHECK-IOS: mov r1, #1
; CHECK-IOS: memset
; CHECK-DARWIN: movs r1, #0
; CHECK-DARWIN: movs r1, #1
; CHECK-DARWIN: memset
; CHECK-EABI: mov r2, #0
; CHECK-EABI: mov r2, #1
; CHECK-EABI: __aeabi_memset
%arr2 = alloca [7 x i8], align 1
%2 = bitcast [7 x i8]* %arr2 to i8*
call void @llvm.memset.p0i8.i32(i8* %2, i8 0, i32 %n, i32 0, i1 false)
call void @llvm.memset.p0i8.i32(i8* %2, i8 1, i32 %n, i32 0, i1 false)
unreachable
}
@ -125,15 +176,15 @@ entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %1, i32 %n, i32 0, i1 false)
; CHECK: {{add(.w)? r., sp, #(1|5)}}
; CHECK-IOS: mov r1, #0
; CHECK-IOS: mov r1, #1
; CHECK-IOS: memset
; CHECK-DARWIN: movs r1, #0
; CHECK-DARWIN: movs r1, #1
; CHECK-DARWIN: memset
; CHECK-EABI: mov r2, #0
; CHECK-EABI: mov r2, #1
; CHECK-EABI: __aeabi_memset
%arr2 = alloca [9 x i8], align 1
%2 = getelementptr inbounds [9 x i8], [9 x i8]* %arr2, i32 0, i32 4
call void @llvm.memset.p0i8.i32(i8* %2, i8 0, i32 %n, i32 0, i1 false)
call void @llvm.memset.p0i8.i32(i8* %2, i8 1, i32 %n, i32 0, i1 false)
unreachable
}
@ -160,15 +211,15 @@ entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %1, i32 %n, i32 0, i1 false)
; CHECK: {{add(.w)? r., sp, #(1|5)}}
; CHECK-IOS: mov r1, #0
; CHECK-IOS: mov r1, #1
; CHECK-IOS: memset
; CHECK-DARWIN: movs r1, #0
; CHECK-DARWIN: movs r1, #1
; CHECK-DARWIN: memset
; CHECK-EABI: mov r2, #0
; CHECK-EABI: mov r2, #1
; CHECK-EABI: __aeabi_memset
%arr2 = alloca [13 x i8], align 1
%2 = getelementptr inbounds [13 x i8], [13 x i8]* %arr2, i32 0, i32 1
call void @llvm.memset.p0i8.i32(i8* %2, i8 0, i32 %n, i32 0, i1 false)
call void @llvm.memset.p0i8.i32(i8* %2, i8 1, i32 %n, i32 0, i1 false)
unreachable
}
@ -195,15 +246,15 @@ entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %1, i32 %n, i32 0, i1 false)
; CHECK: {{add(.w)? r., sp, #(1|5)}}
; CHECK-IOS: mov r1, #0
; CHECK-IOS: mov r1, #1
; CHECK-IOS: memset
; CHECK-DARWIN: movs r1, #0
; CHECK-DARWIN: movs r1, #1
; CHECK-DARWIN: memset
; CHECK-EABI: mov r2, #0
; CHECK-EABI: mov r2, #1
; CHECK-EABI: __aeabi_memset
%arr2 = alloca [13 x i8], align 1
%2 = getelementptr inbounds [13 x i8], [13 x i8]* %arr2, i32 0, i32 %i
call void @llvm.memset.p0i8.i32(i8* %2, i8 0, i32 %n, i32 0, i1 false)
call void @llvm.memset.p0i8.i32(i8* %2, i8 1, i32 %n, i32 0, i1 false)
unreachable
}
@ -230,15 +281,15 @@ entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %1, i32 %n, i32 0, i1 false)
; CHECK: {{add(.w)? r., sp, #(1|5)}}
; CHECK-IOS: mov r1, #0
; CHECK-IOS: mov r1, #1
; CHECK-IOS: memset
; CHECK-DARWIN: movs r1, #0
; CHECK-DARWIN: movs r1, #1
; CHECK-DARWIN: memset
; CHECK-EABI: mov r2, #0
; CHECK-EABI: mov r2, #1
; CHECK-EABI: __aeabi_memset
%arr2 = alloca [13 x i8], align 1
%2 = getelementptr [13 x i8], [13 x i8]* %arr2, i32 0, i32 4
call void @llvm.memset.p0i8.i32(i8* %2, i8 0, i32 %n, i32 0, i1 false)
call void @llvm.memset.p0i8.i32(i8* %2, i8 1, i32 %n, i32 0, i1 false)
unreachable
}
@ -265,15 +316,15 @@ entry:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %1, i32 %n, i32 0, i1 false)
; CHECK: {{add(.w)? r., sp, #(1|5)}}
; CHECK-IOS: mov r1, #0
; CHECK-IOS: mov r1, #1
; CHECK-IOS: memset
; CHECK-DARWIN: movs r1, #0
; CHECK-DARWIN: movs r1, #1
; CHECK-DARWIN: memset
; CHECK-EABI: mov r2, #0
; CHECK-EABI: mov r2, #1
; CHECK-EABI: __aeabi_memset
%arr2 = alloca [13 x i8], align 1
%2 = getelementptr inbounds [13 x i8], [13 x i8]* %arr2, i32 0, i32 16
call void @llvm.memset.p0i8.i32(i8* %2, i8 0, i32 %n, i32 0, i1 false)
call void @llvm.memset.p0i8.i32(i8* %2, i8 1, i32 %n, i32 0, i1 false)
unreachable
}