#define LLVM_CODEGEN_FASTISEL_H
#include "llvm/ADT/DenseMap.h"
+#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/IR/CallingConv.h"
namespace llvm {
/// This is a fast-path instruction selection class that generates poor code and
/// doesn't support illegal types or non-trivial lowering, but runs quickly.
class FastISel {
+ public:
+ struct ArgListEntry {
+ Value *Val;
+ Type *Ty;
+ bool isSExt : 1;
+ bool isZExt : 1;
+ bool isInReg : 1;
+ bool isSRet : 1;
+ bool isNest : 1;
+ bool isByVal : 1;
+ bool isInAlloca : 1;
+ bool isReturned : 1;
+ uint16_t Alignment;
+
+ ArgListEntry()
+ : Val(nullptr), Ty(nullptr), isSExt(false), isZExt(false), isInReg(false),
+ isSRet(false), isNest(false), isByVal(false), isInAlloca(false),
+ isReturned(false), Alignment(0) { }
+
+ void setAttributes(ImmutableCallSite *CS, unsigned AttrIdx);
+ };
+ typedef std::vector<ArgListEntry> ArgListTy;
+
+ struct CallLoweringInfo {
+ Type *RetTy;
+ bool RetSExt : 1;
+ bool RetZExt : 1;
+ bool IsVarArg : 1;
+ bool IsInReg : 1;
+ bool DoesNotReturn : 1;
+ bool IsReturnValueUsed : 1;
+
+ // IsTailCall should be modified by implementations of
+ // FastLowerCall that perform tail call conversions.
+ bool IsTailCall;
+
+ unsigned NumFixedArgs;
+ CallingConv::ID CallConv;
+ const Value *Callee;
+ const char *SymName;
+ ArgListTy Args;
+ ImmutableCallSite *CS;
+ MachineInstr *Call;
+ unsigned ResultReg;
+ unsigned NumResultRegs;
+
+ SmallVector<Value *, 16> OutVals;
+ SmallVector<ISD::ArgFlagsTy, 16> OutFlags;
+ SmallVector<unsigned, 16> OutRegs;
+ SmallVector<ISD::InputArg, 4> Ins;
+ SmallVector<unsigned, 4> InRegs;
+
+ CallLoweringInfo()
+ : RetTy(nullptr), RetSExt(false), RetZExt(false), IsVarArg(false),
+ IsInReg(false), DoesNotReturn(false), IsReturnValueUsed(true),
+ IsTailCall(false), NumFixedArgs(-1), CallConv(CallingConv::C),
+ Callee(nullptr), SymName(nullptr), CS(nullptr), Call(nullptr),
+ ResultReg(0), NumResultRegs(0)
+ {}
+
+ CallLoweringInfo &setCallee(Type *ResultTy, FunctionType *FuncTy,
+ const Value *Target, ArgListTy &&ArgsList,
+ ImmutableCallSite &Call) {
+ RetTy = ResultTy;
+ Callee = Target;
+
+ IsInReg = Call.paramHasAttr(0, Attribute::InReg);
+ DoesNotReturn = Call.doesNotReturn();
+ IsVarArg = FuncTy->isVarArg();
+ IsReturnValueUsed = !Call.getInstruction()->use_empty();
+ RetSExt = Call.paramHasAttr(0, Attribute::SExt);
+ RetZExt = Call.paramHasAttr(0, Attribute::ZExt);
+
+ CallConv = Call.getCallingConv();
+ NumFixedArgs = FuncTy->getNumParams();
+ Args = std::move(ArgsList);
+
+ CS = &Call;
+
+ return *this;
+ }
+
+ CallLoweringInfo &setCallee(Type *ResultTy, FunctionType *FuncTy,
+ const char *Target, ArgListTy &&ArgsList,
+ ImmutableCallSite &Call,
+ unsigned FixedArgs = ~0U) {
+ RetTy = ResultTy;
+ Callee = Call.getCalledValue();
+ SymName = Target;
+
+ IsInReg = Call.paramHasAttr(0, Attribute::InReg);
+ DoesNotReturn = Call.doesNotReturn();
+ IsVarArg = FuncTy->isVarArg();
+ IsReturnValueUsed = !Call.getInstruction()->use_empty();
+ RetSExt = Call.paramHasAttr(0, Attribute::SExt);
+ RetZExt = Call.paramHasAttr(0, Attribute::ZExt);
+
+ CallConv = Call.getCallingConv();
+ NumFixedArgs = (FixedArgs == ~0U) ? FuncTy->getNumParams() : FixedArgs;
+ Args = std::move(ArgsList);
+
+ CS = &Call;
+
+ return *this;
+ }
+
+ CallLoweringInfo &setCallee(CallingConv::ID CC, Type *ResultTy,
+ const Value *Target, ArgListTy &&ArgsList,
+ unsigned FixedArgs = ~0U) {
+ RetTy = ResultTy;
+ Callee = Target;
+ CallConv = CC;
+ NumFixedArgs = (FixedArgs == ~0U) ? Args.size() : FixedArgs;
+ Args = std::move(ArgsList);
+ return *this;
+ }
+
+ CallLoweringInfo &setTailCall(bool Value = true) {
+ IsTailCall = Value;
+ return *this;
+ }
+
+ ArgListTy &getArgs() {
+ return Args;
+ }
+
+ void clearOuts() {
+ OutVals.clear();
+ OutFlags.clear();
+ OutRegs.clear();
+ }
+
+ void clearIns() {
+ Ins.clear();
+ InRegs.clear();
+ }
+ };
+
protected:
DenseMap<const Value *, unsigned> LocalValueMap;
FunctionLoweringInfo &FuncInfo;
/// process fails to select an instruction. This gives targets a chance to
/// emit code for anything that doesn't fit into FastISel's framework. It
/// returns true if it was successful.
- virtual bool
- TargetSelectInstruction(const Instruction *I) = 0;
+ virtual bool TargetSelectInstruction(const Instruction *I) = 0;
/// This method is called by target-independent code to do target specific
/// argument lowering. It returns true if it was successful.
virtual bool FastLowerArguments();
- /// This method is called by target-independent code to do target specific
- /// intrinsic lowering. It returns true if it was successful.
+ /// \brief This method is called by target-independent code to do target
+ /// specific call lowering. It returns true if it was successful.
+ virtual bool FastLowerCall(CallLoweringInfo &CLI);
+
+ /// \brief This method is called by target-independent code to do target
+ /// specific intrinsic lowering. It returns true if it was successful.
virtual bool FastLowerIntrinsicCall(const IntrinsicInst *II);
/// This method is called by target-independent code to request that an
/// \brief Create a machine mem operand from the given instruction.
MachineMemOperand *createMachineMemOperandFor(const Instruction *I) const;
+ bool LowerCallTo(const CallInst *CI, const char *SymName, unsigned NumArgs);
+ bool LowerCallTo(CallLoweringInfo &CLI);
+
private:
bool SelectBinaryOp(const User *I, unsigned ISDOpcode);
bool SelectGetElementPtr(const User *I);
bool SelectStackmap(const CallInst *I);
- bool SelectCall(const User *I);
+ bool LowerCall(const CallInst *I);
+ bool SelectCall(const User *Call);
bool SelectIntrinsicCall(const IntrinsicInst *II);
bool SelectBitCast(const User *I);
//
//===----------------------------------------------------------------------===//
+#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/Statistic.h"
"target-specific selector");
STATISTIC(NumFastIselDead, "Number of dead insts removed on failure");
+/// \brief Set CallLoweringInfo attribute flags based on a call instruction
+/// and called function attributes.
+void FastISel::ArgListEntry::setAttributes(ImmutableCallSite *CS,
+ unsigned AttrIdx) {
+ isSExt = CS->paramHasAttr(AttrIdx, Attribute::SExt);
+ isZExt = CS->paramHasAttr(AttrIdx, Attribute::ZExt);
+ isInReg = CS->paramHasAttr(AttrIdx, Attribute::InReg);
+ isSRet = CS->paramHasAttr(AttrIdx, Attribute::StructRet);
+ isNest = CS->paramHasAttr(AttrIdx, Attribute::Nest);
+ isByVal = CS->paramHasAttr(AttrIdx, Attribute::ByVal);
+ isInAlloca = CS->paramHasAttr(AttrIdx, Attribute::InAlloca);
+ isReturned = CS->paramHasAttr(AttrIdx, Attribute::Returned);
+ Alignment = CS->getParamAlignment(AttrIdx);
+}
+
/// startNewBlock - Set the current block to which generated machine
/// instructions will be appended, and clear the local CSE map.
///
return true;
}
+/// Returns an AttributeSet representing the attributes applied to the return
+/// value of the given call.
+static AttributeSet getReturnAttrs(FastISel::CallLoweringInfo &CLI) {
+ SmallVector<Attribute::AttrKind, 2> Attrs;
+ if (CLI.RetSExt)
+ Attrs.push_back(Attribute::SExt);
+ if (CLI.RetZExt)
+ Attrs.push_back(Attribute::ZExt);
+ if (CLI.IsInReg)
+ Attrs.push_back(Attribute::InReg);
+
+ return AttributeSet::get(CLI.RetTy->getContext(), AttributeSet::ReturnIndex,
+ Attrs);
+}
+
+bool FastISel::LowerCallTo(const CallInst *CI, const char *SymName,
+ unsigned NumArgs) {
+ ImmutableCallSite CS(CI);
+
+ PointerType *PT = cast<PointerType>(CS.getCalledValue()->getType());
+ FunctionType *FTy = cast<FunctionType>(PT->getElementType());
+ Type *RetTy = FTy->getReturnType();
+
+ ArgListTy Args;
+ Args.reserve(NumArgs);
+
+ // Populate the argument list.
+ // Attributes for args start at offset 1, after the return attribute.
+ for (unsigned ArgI = 0; ArgI != NumArgs; ++ArgI) {
+ Value *V = CI->getOperand(ArgI);
+
+ assert(!V->getType()->isEmptyTy() && "Empty type passed to intrinsic.");
+
+ ArgListEntry Entry;
+ Entry.Val = V;
+ Entry.Ty = V->getType();
+ Entry.setAttributes(&CS, ArgI + 1);
+ Args.push_back(Entry);
+ }
+
+ CallLoweringInfo CLI;
+ CLI.setCallee(RetTy, FTy, SymName, std::move(Args), CS, NumArgs);
+
+ return LowerCallTo(CLI);
+}
+
+bool FastISel::LowerCallTo(CallLoweringInfo &CLI) {
+ // Handle the incoming return values from the call.
+ CLI.clearIns();
+ SmallVector<EVT, 4> RetTys;
+ ComputeValueVTs(TLI, CLI.RetTy, RetTys);
+
+ SmallVector<ISD::OutputArg, 4> Outs;
+ GetReturnInfo(CLI.RetTy, getReturnAttrs(CLI), Outs, TLI);
+
+ bool CanLowerReturn = TLI.CanLowerReturn(CLI.CallConv, *FuncInfo.MF,
+ CLI.IsVarArg, Outs,
+ CLI.RetTy->getContext());
+
+ // FIXME: sret demotion isn't supported yet - bail out.
+ if (!CanLowerReturn)
+ return false;
+
+ for (unsigned I = 0, E = RetTys.size(); I != E; ++I) {
+ EVT VT = RetTys[I];
+ MVT RegisterVT = TLI.getRegisterType(CLI.RetTy->getContext(), VT);
+ unsigned NumRegs = TLI.getNumRegisters(CLI.RetTy->getContext(), VT);
+ for (unsigned i = 0; i != NumRegs; ++i) {
+ ISD::InputArg MyFlags;
+ MyFlags.VT = RegisterVT;
+ MyFlags.ArgVT = VT;
+ MyFlags.Used = CLI.IsReturnValueUsed;
+ if (CLI.RetSExt)
+ MyFlags.Flags.setSExt();
+ if (CLI.RetZExt)
+ MyFlags.Flags.setZExt();
+ if (CLI.IsInReg)
+ MyFlags.Flags.setInReg();
+ CLI.Ins.push_back(MyFlags);
+ }
+ }
+
+ // Handle all of the outgoing arguments.
+ CLI.clearOuts();
+ for (auto &Arg : CLI.getArgs()) {
+ Type *FinalType = Arg.Ty;
+ if (Arg.isByVal)
+ FinalType = cast<PointerType>(Arg.Ty)->getElementType();
+ bool NeedsRegBlock = TLI.functionArgumentNeedsConsecutiveRegisters(
+ FinalType, CLI.CallConv, CLI.IsVarArg);
+
+ ISD::ArgFlagsTy Flags;
+ if (Arg.isZExt)
+ Flags.setZExt();
+ if (Arg.isSExt)
+ Flags.setSExt();
+ if (Arg.isInReg)
+ Flags.setInReg();
+ if (Arg.isSRet)
+ Flags.setSRet();
+ if (Arg.isByVal)
+ Flags.setByVal();
+ if (Arg.isInAlloca) {
+ Flags.setInAlloca();
+ // Set the byval flag for CCAssignFn callbacks that don't know about
+ // inalloca. This way we can know how many bytes we should've allocated
+ // and how many bytes a callee cleanup function will pop. If we port
+ // inalloca to more targets, we'll have to add custom inalloca handling in
+ // the various CC lowering callbacks.
+ Flags.setByVal();
+ }
+ if (Arg.isByVal || Arg.isInAlloca) {
+ PointerType *Ty = cast<PointerType>(Arg.Ty);
+ Type *ElementTy = Ty->getElementType();
+ unsigned FrameSize = DL.getTypeAllocSize(ElementTy);
+ // For ByVal, alignment should come from FE. BE will guess if this info is
+ // not there, but there are cases it cannot get right.
+ unsigned FrameAlign = Arg.Alignment;
+ if (!FrameAlign)
+ FrameAlign = TLI.getByValTypeAlignment(ElementTy);
+ Flags.setByValSize(FrameSize);
+ Flags.setByValAlign(FrameAlign);
+ }
+ if (Arg.isNest)
+ Flags.setNest();
+ if (NeedsRegBlock)
+ Flags.setInConsecutiveRegs();
+ unsigned OriginalAlignment = DL.getABITypeAlignment(Arg.Ty);
+ Flags.setOrigAlign(OriginalAlignment);
+
+ CLI.OutVals.push_back(Arg.Val);
+ CLI.OutFlags.push_back(Flags);
+ }
+
+ if (!FastLowerCall(CLI))
+ return false;
+
+ // Set all unused physreg defs as dead.
+ assert(CLI.Call && "No call instruction specified.");
+ CLI.Call->setPhysRegsDeadExcept(CLI.InRegs, TRI);
+
+ if (CLI.NumResultRegs && CLI.CS)
+ UpdateValueMap(CLI.CS->getInstruction(), CLI.ResultReg, CLI.NumResultRegs);
+
+ return true;
+}
+
+bool FastISel::LowerCall(const CallInst *CI) {
+ ImmutableCallSite CS(CI);
+
+ PointerType *PT = cast<PointerType>(CS.getCalledValue()->getType());
+ FunctionType *FuncTy = cast<FunctionType>(PT->getElementType());
+ Type *RetTy = FuncTy->getReturnType();
+
+ ArgListTy Args;
+ ArgListEntry Entry;
+ Args.reserve(CS.arg_size());
+
+ for (ImmutableCallSite::arg_iterator i = CS.arg_begin(), e = CS.arg_end();
+ i != e; ++i) {
+ Value *V = *i;
+
+ // Skip empty types
+ if (V->getType()->isEmptyTy())
+ continue;
+
+ Entry.Val = V;
+ Entry.Ty = V->getType();
+
+ // Skip the first return-type Attribute to get to params.
+ Entry.setAttributes(&CS, i - CS.arg_begin() + 1);
+ Args.push_back(Entry);
+ }
+
+ // Check if target-independent constraints permit a tail call here.
+ // Target-dependent constraints are checked within FastLowerCall.
+ bool IsTailCall = CI->isTailCall();
+ if (IsTailCall && !isInTailCallPosition(CS, TM, TLI))
+ IsTailCall = false;
+
+ CallLoweringInfo CLI;
+ CLI.setCallee(RetTy, FuncTy, CI->getCalledValue(), std::move(Args), CS)
+ .setTailCall(IsTailCall);
+
+ return LowerCallTo(CLI);
+}
+
bool FastISel::SelectCall(const User *I) {
const CallInst *Call = cast<CallInst>(I);
// since they tend to be inlined.
flushLocalValueMap();
- // An arbitrary call. Bail.
- return false;
+ return LowerCall(Call);
}
bool FastISel::SelectIntrinsicCall(const IntrinsicInst *II) {
return false;
}
+bool FastISel::FastLowerCall(CallLoweringInfo &/*CLI*/) {
+ return false;
+}
+
bool FastISel::FastLowerIntrinsicCall(const IntrinsicInst */*II*/) {
return false;
}