SDValue getMemcpy(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
SDValue Size, unsigned Align, bool isVol, bool AlwaysInline,
- MachinePointerInfo DstPtrInfo,
+ bool isTailCall, MachinePointerInfo DstPtrInfo,
MachinePointerInfo SrcPtrInfo);
SDValue getMemmove(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
- SDValue Size, unsigned Align, bool isVol,
+ SDValue Size, unsigned Align, bool isVol, bool isTailCall,
MachinePointerInfo DstPtrInfo,
MachinePointerInfo SrcPtrInfo);
SDValue getMemset(SDValue Chain, SDLoc dl, SDValue Dst, SDValue Src,
- SDValue Size, unsigned Align, bool isVol,
+ SDValue Size, unsigned Align, bool isVol, bool isTailCall,
MachinePointerInfo DstPtrInfo);
/// Helper function to make it easier to build SetCC's if you just
SDValue SelectionDAG::getMemcpy(SDValue Chain, SDLoc dl, SDValue Dst,
SDValue Src, SDValue Size,
unsigned Align, bool isVol, bool AlwaysInline,
- MachinePointerInfo DstPtrInfo,
+ bool isTailCall, MachinePointerInfo DstPtrInfo,
MachinePointerInfo SrcPtrInfo) {
assert(Align && "The SDAG layer expects explicit alignment and reserves 0");
Type::getVoidTy(*getContext()),
getExternalSymbol(TLI->getLibcallName(RTLIB::MEMCPY),
TLI->getPointerTy()), std::move(Args), 0)
- .setDiscardResult();
- std::pair<SDValue,SDValue> CallResult = TLI->LowerCallTo(CLI);
+ .setDiscardResult()
+ .setTailCall(isTailCall);
+ std::pair<SDValue,SDValue> CallResult = TLI->LowerCallTo(CLI);
return CallResult.second;
}
SDValue SelectionDAG::getMemmove(SDValue Chain, SDLoc dl, SDValue Dst,
SDValue Src, SDValue Size,
- unsigned Align, bool isVol,
+ unsigned Align, bool isVol, bool isTailCall,
MachinePointerInfo DstPtrInfo,
MachinePointerInfo SrcPtrInfo) {
assert(Align && "The SDAG layer expects explicit alignment and reserves 0");
Type::getVoidTy(*getContext()),
getExternalSymbol(TLI->getLibcallName(RTLIB::MEMMOVE),
TLI->getPointerTy()), std::move(Args), 0)
- .setDiscardResult();
- std::pair<SDValue,SDValue> CallResult = TLI->LowerCallTo(CLI);
+ .setDiscardResult()
+ .setTailCall(isTailCall);
+ std::pair<SDValue,SDValue> CallResult = TLI->LowerCallTo(CLI);
return CallResult.second;
}
SDValue SelectionDAG::getMemset(SDValue Chain, SDLoc dl, SDValue Dst,
SDValue Src, SDValue Size,
- unsigned Align, bool isVol,
+ unsigned Align, bool isVol, bool isTailCall,
MachinePointerInfo DstPtrInfo) {
assert(Align && "The SDAG layer expects explicit alignment and reserves 0");
Type::getVoidTy(*getContext()),
getExternalSymbol(TLI->getLibcallName(RTLIB::MEMSET),
TLI->getPointerTy()), std::move(Args), 0)
- .setDiscardResult();
+ .setDiscardResult()
+ .setTailCall(isTailCall);
std::pair<SDValue,SDValue> CallResult = TLI->LowerCallTo(CLI);
return CallResult.second;
if (!Align)
Align = 1; // @llvm.memcpy defines 0 and 1 to both mean no alignment.
bool isVol = cast<ConstantInt>(I.getArgOperand(4))->getZExtValue();
- DAG.setRoot(DAG.getMemcpy(getRoot(), sdl, Op1, Op2, Op3, Align, isVol, false,
- MachinePointerInfo(I.getArgOperand(0)),
- MachinePointerInfo(I.getArgOperand(1))));
+ bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget());
+ SDValue MC = DAG.getMemcpy(getRoot(), sdl, Op1, Op2, Op3, Align, isVol,
+ false, isTC,
+ MachinePointerInfo(I.getArgOperand(0)),
+ MachinePointerInfo(I.getArgOperand(1)));
+ updateDAGForMaybeTailCall(MC);
return nullptr;
}
case Intrinsic::memset: {
if (!Align)
Align = 1; // @llvm.memset defines 0 and 1 to both mean no alignment.
bool isVol = cast<ConstantInt>(I.getArgOperand(4))->getZExtValue();
- DAG.setRoot(DAG.getMemset(getRoot(), sdl, Op1, Op2, Op3, Align, isVol,
- MachinePointerInfo(I.getArgOperand(0))));
+ bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget());
+ SDValue MS = DAG.getMemset(getRoot(), sdl, Op1, Op2, Op3, Align, isVol,
+ isTC, MachinePointerInfo(I.getArgOperand(0)));
+ updateDAGForMaybeTailCall(MS);
return nullptr;
}
case Intrinsic::memmove: {
if (!Align)
Align = 1; // @llvm.memmove defines 0 and 1 to both mean no alignment.
bool isVol = cast<ConstantInt>(I.getArgOperand(4))->getZExtValue();
- DAG.setRoot(DAG.getMemmove(getRoot(), sdl, Op1, Op2, Op3, Align, isVol,
- MachinePointerInfo(I.getArgOperand(0)),
- MachinePointerInfo(I.getArgOperand(1))));
+ bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget());
+ SDValue MM = DAG.getMemmove(getRoot(), sdl, Op1, Op2, Op3, Align, isVol,
+ isTC, MachinePointerInfo(I.getArgOperand(0)),
+ MachinePointerInfo(I.getArgOperand(1)));
+ updateDAGForMaybeTailCall(MM);
return nullptr;
}
case Intrinsic::dbg_declare: {
return nullptr;
return I;
}
+
+/// During lowering new call nodes can be created (such as memset, etc.).
+/// Those will become new roots of the current DAG, but complications arise
+/// when they are tail calls. In such cases, the call lowering will update
+/// the root, but the builder still needs to know that a tail call has been
+/// lowered in order to avoid generating an additional return.
+void SelectionDAGBuilder::updateDAGForMaybeTailCall(SDValue MaybeTC) {
+ // If the node is null, we do have a tail call.
+ if (MaybeTC.getNode() != nullptr)
+ DAG.setRoot(MaybeTC);
+ else
+ HasTailCall = true;
+}
+
/// Return the next block after MBB, or nullptr if there is none.
MachineBasicBlock *NextBlock(MachineBasicBlock *MBB);
+
+ /// Update the DAG and DAG builder with the relevant information after
+ /// a new root node has been created which could be a tail call.
+ void updateDAGForMaybeTailCall(SDValue MaybeTC);
};
} // end namespace llvm
DAG.getConstant(Outs[i].Flags.getByValSize(), MVT::i64);
SDValue Cpy = DAG.getMemcpy(
Chain, DL, DstAddr, Arg, SizeNode, Outs[i].Flags.getByValAlign(),
- /*isVol = */ false,
- /*AlwaysInline = */ false, DstInfo, MachinePointerInfo());
+ /*isVol = */ false, /*AlwaysInline = */ false,
+ /*isTailCall = */ false,
+ DstInfo, MachinePointerInfo());
MemOpChains.push_back(Cpy);
} else {
return DAG.getMemcpy(Op.getOperand(0), SDLoc(Op), Op.getOperand(1),
Op.getOperand(2), DAG.getConstant(VaListSize, MVT::i32),
- 8, false, false, MachinePointerInfo(DestSV),
+ 8, false, false, false, MachinePointerInfo(DestSV),
MachinePointerInfo(SrcSV));
}
SDValue SizeNode = DAG.getConstant(Flags.getByValSize(), MVT::i32);
return DAG.getMemcpy(Chain, dl, Dst, Src, SizeNode, Flags.getByValAlign(),
/*isVolatile=*/false, /*AlwaysInline=*/false,
+ /*isTailCall=*/false,
MachinePointerInfo(), MachinePointerInfo());
}
Flags.getByValAlign(),
/*isVolatile*/false,
/*AlwaysInline=*/true,
+ /*isTailCall=*/false,
MachinePointerInfo(),
MachinePointerInfo());
} else {
DAG.getIntPtrConstant(VA.getLocMemOffset()));
Chain = DAG.getMemcpy(Chain, DL, Dst, Src, DAG.getConstant(MemCpySize, PtrTy),
Alignment, /*isVolatile=*/false, /*AlwaysInline=*/false,
+ /*isTailCall=*/false,
MachinePointerInfo(), MachinePointerInfo());
MemOpChains.push_back(Chain);
}
// 2*sizeof(char) + 2 Byte alignment + 2*sizeof(char*) = 12 Byte
return DAG.getMemcpy(Op.getOperand(0), Op,
Op.getOperand(1), Op.getOperand(2),
- DAG.getConstant(12, MVT::i32), 8, false, true,
+ DAG.getConstant(12, MVT::i32), 8, false, true, false,
MachinePointerInfo(), MachinePointerInfo());
}
SDLoc dl) {
SDValue SizeNode = DAG.getConstant(Flags.getByValSize(), MVT::i32);
return DAG.getMemcpy(Chain, dl, Dst, Src, SizeNode, Flags.getByValAlign(),
- false, false, MachinePointerInfo(),
+ false, false, false, MachinePointerInfo(),
MachinePointerInfo());
}
Chain = DAG.getMemcpy(Chain, dl, FIPtr, Arg, SizeNode, Align,
false, // isVolatile,
- (Size <= 32), // AlwaysInline if size <= 32
+ (Size <= 32), // AlwaysInline if size <= 32,
+ false, // isTailCall
MachinePointerInfo(), MachinePointerInfo());
ByValArgs.push_back(FIPtr);
}
return DAG.getMemcpy(Chain, DL, DstPtr, SrcPtr, DAG.getIntPtrConstant(32),
/*Align*/8, /*isVolatile*/false, /*AlwaysInline*/false,
+ /*isTailCall*/false,
MachinePointerInfo(DstSV), MachinePointerInfo(SrcSV));
}
return DAG.getMemcpy(Chain, dl, Dst, Src, SizeNode, Flags.getByValAlign(),
/*isVolatile*/false, /*AlwaysInline=*/true,
+ /*isTailCall*/false,
MachinePointerInfo(), MachinePointerInfo());
}
return DAG.getMemcpy(Chain, DL, DstPtr, SrcPtr,
DAG.getIntPtrConstant(24), 8, /*isVolatile*/false,
- false,
+ false, false,
MachinePointerInfo(DstSV), MachinePointerInfo(SrcSV));
}
DAG.getConstant(Offset, AddrVT)),
Src,
DAG.getConstant(BytesLeft, SizeVT),
- Align, isVolatile, DstPtrInfo.getWithOffset(Offset));
+ Align, isVolatile, false,
+ DstPtrInfo.getWithOffset(Offset));
}
// TODO: Use a Tokenfactor, as in memcpy, instead of a single chain.
DAG.getNode(ISD::ADD, dl, SrcVT, Src,
DAG.getConstant(Offset, SrcVT)),
DAG.getConstant(BytesLeft, SizeVT),
- Align, isVolatile, AlwaysInline,
+ Align, isVolatile, AlwaysInline, false,
DstPtrInfo.getWithOffset(Offset),
SrcPtrInfo.getWithOffset(Offset)));
}
InVals.push_back(FIN);
MemOps.push_back(DAG.getMemcpy(Chain, dl, FIN, ArgDI->SDV,
DAG.getConstant(Size, MVT::i32),
- Align, false, false,
+ Align, false, false, false,
MachinePointerInfo(),
MachinePointerInfo()));
} else {
LD->getAlignment() == Alignment &&
!LD->isVolatile() && !LD->isIndexed() &&
Chain.reachesChainWithoutSideEffects(SDValue(LD, 1))) {
+ bool isTail = isInTailCallPosition(DAG, ST, Chain);
return DAG.getMemmove(Chain, dl, ST->getBasePtr(),
LD->getBasePtr(),
DAG.getConstant(StoreBits/8, MVT::i32),
- Alignment, false, ST->getPointerInfo(),
+ Alignment, false, isTail, ST->getPointerInfo(),
LD->getPointerInfo());
}
}
--- /dev/null
+; RUN: llc -march=aarch64 < %s | FileCheck %s
+
+; CHECK-LABEL: tail_memcpy:
+; CHECK: b memcpy
+define void @tail_memcpy(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memmove:
+; CHECK: b memmove
+define void @tail_memmove(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memset:
+; CHECK: b memset
+define void @tail_memset(i8* nocapture %p, i8 %c, i32 %n) #0 {
+entry:
+ tail call void @llvm.memset.p0i8.i32(i8* %p, i8 %c, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i32, i1) #0
+
+attributes #0 = { nounwind }
--- /dev/null
+; RUN: llc -march=arm < %s | FileCheck %s
+
+; CHECK-LABEL: tail_memcpy:
+; CHECK: b memcpy
+define void @tail_memcpy(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memmove:
+; CHECK: b memmove
+define void @tail_memmove(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memset:
+; CHECK: b memset
+define void @tail_memset(i8* nocapture %p, i8 %c, i32 %n) #0 {
+entry:
+ tail call void @llvm.memset.p0i8.i32(i8* %p, i8 %c, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i32, i1) #0
+
+attributes #0 = { nounwind }
--- /dev/null
+; RUN: llc -march=hexagon < %s | FileCheck %s
+
+; CHECK-LABEL: tail_memcpy:
+; CHECK: jump memcpy
+define void @tail_memcpy(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memmove:
+; CHECK: jump memmove
+define void @tail_memmove(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memset:
+; CHECK: jump memset
+define void @tail_memset(i8* nocapture %p, i8 %c, i32 %n) #0 {
+entry:
+ tail call void @llvm.memset.p0i8.i32(i8* %p, i8 %c, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i32, i1) #0
+
+attributes #0 = { nounwind }
--- /dev/null
+; RUN: llc -march=systemz < %s | FileCheck %s
+
+; CHECK-LABEL: tail_memcpy:
+; CHECK: jg memcpy
+define void @tail_memcpy(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memmove:
+; CHECK: jg memmove
+define void @tail_memmove(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memset:
+; CHECK: jg memset
+define void @tail_memset(i8* nocapture %p, i8 %c, i32 %n) #0 {
+entry:
+ tail call void @llvm.memset.p0i8.i32(i8* %p, i8 %c, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i32, i1) #0
+
+attributes #0 = { nounwind }
--- /dev/null
+; RUN: llc -march=x86 < %s | FileCheck %s
+
+; CHECK-LABEL: tail_memcpy
+; CHECK: jmp memcpy
+define void @tail_memcpy(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memcpy.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memset
+; CHECK; jmp memmove
+define void @tail_memmove(i8* nocapture %p, i8* nocapture readonly %q, i32 %n) #0 {
+entry:
+ tail call void @llvm.memmove.p0i8.p0i8.i32(i8* %p, i8* %q, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+; CHECK-LABEL: tail_memset
+; CHECK: jmp memset
+define void @tail_memset(i8* nocapture %p, i8 %c, i32 %n) #0 {
+entry:
+ tail call void @llvm.memset.p0i8.i32(i8* %p, i8 %c, i32 %n, i32 1, i1 false)
+ ret void
+}
+
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memmove.p0i8.p0i8.i32(i8* nocapture, i8* nocapture readonly, i32, i32, i1) #0
+declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i32, i1) #0
+
+attributes #0 = { nounwind }