//===----------------------------------------------------------------------===//
//
// This file defines the FastISel class.
-//
+//
//===----------------------------------------------------------------------===//
-
+
#ifndef LLVM_CODEGEN_FASTISEL_H
#define LLVM_CODEGEN_FASTISEL_H
-#include "llvm/BasicBlock.h"
#include "llvm/ADT/DenseMap.h"
-#include "llvm/CodeGen/SelectionDAGNodes.h"
+#include "llvm/CodeGen/ValueTypes.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
namespace llvm {
+class AllocaInst;
+class Constant;
class ConstantFP;
+class FunctionLoweringInfo;
+class Instruction;
+class LoadInst;
class MachineBasicBlock;
+class MachineConstantPool;
class MachineFunction;
+class MachineInstr;
+class MachineFrameInfo;
class MachineRegisterInfo;
class TargetData;
class TargetInstrInfo;
class TargetLowering;
class TargetMachine;
class TargetRegisterClass;
+class TargetRegisterInfo;
+class User;
+class Value;
/// FastISel - 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 {
protected:
- MachineBasicBlock *MBB;
- MachineFunction &MF;
+ DenseMap<const Value *, unsigned> LocalValueMap;
+ FunctionLoweringInfo &FuncInfo;
MachineRegisterInfo &MRI;
+ MachineFrameInfo &MFI;
+ MachineConstantPool &MCP;
+ DebugLoc DL;
const TargetMachine &TM;
const TargetData &TD;
const TargetInstrInfo &TII;
const TargetLowering &TLI;
+ const TargetRegisterInfo &TRI;
+
+ /// The position of the last instruction for materializing constants
+ /// for use in the current block. It resets to EmitStartPt when it
+ /// makes sense (for example, it's usually profitable to avoid function
+ /// calls between the definition and the use)
+ MachineInstr *LastLocalValue;
+
+ /// The top most instruction in the current block that is allowed for
+ /// emitting local variables. LastLocalValue resets to EmitStartPt when
+ /// it makes sense (for example, on function calls)
+ MachineInstr *EmitStartPt;
public:
- /// SelectInstructions - Do "fast" instruction selection over the
- /// LLVM IR instructions in the range [Begin, N) where N is either
- /// End or the first unsupported instruction. Return N.
- /// ValueMap is filled in with a mapping of LLVM IR Values to
- /// virtual register numbers. MBB is a block to which to append
- /// the generated MachineInstrs.
- BasicBlock::iterator
- SelectInstructions(BasicBlock::iterator Begin, BasicBlock::iterator End,
- DenseMap<const Value*, unsigned> &ValueMap,
- DenseMap<const BasicBlock*, MachineBasicBlock *> &MBBMap,
- MachineBasicBlock *MBB);
+ /// getLastLocalValue - Return the position of the last instruction
+ /// emitted for materializing constants for use in the current block.
+ MachineInstr *getLastLocalValue() { return LastLocalValue; }
+
+ /// setLastLocalValue - Update the position of the last instruction
+ /// emitted for materializing constants for use in the current block.
+ void setLastLocalValue(MachineInstr *I) {
+ EmitStartPt = I;
+ LastLocalValue = I;
+ }
+
+ /// startNewBlock - Set the current block to which generated machine
+ /// instructions will be appended, and clear the local CSE map.
+ ///
+ void startNewBlock();
+
+ /// getCurDebugLoc() - Return current debug location information.
+ DebugLoc getCurDebugLoc() const { return DL; }
+
+ /// SelectInstruction - Do "fast" instruction selection for the given
+ /// LLVM IR instruction, and append generated machine instructions to
+ /// the current block. Return true if selection was successful.
+ ///
+ bool SelectInstruction(const Instruction *I);
+
+ /// SelectOperator - Do "fast" instruction selection for the given
+ /// LLVM IR operator (Instruction or ConstantExpr), and append
+ /// generated machine instructions to the current block. Return true
+ /// if selection was successful.
+ ///
+ bool SelectOperator(const User *I, unsigned Opcode);
+
+ /// getRegForValue - Create a virtual register and arrange for it to
+ /// be assigned the value for the given LLVM value.
+ unsigned getRegForValue(const Value *V);
+
+ /// lookUpRegForValue - Look up the value to see if its value is already
+ /// cached in a register. It may be defined by instructions across blocks or
+ /// defined locally.
+ unsigned lookUpRegForValue(const Value *V);
+
+ /// getRegForGEPIndex - This is a wrapper around getRegForValue that also
+ /// takes care of truncating or sign-extending the given getelementptr
+ /// index value.
+ std::pair<unsigned, bool> getRegForGEPIndex(const Value *V);
+
+ /// TryToFoldLoad - The specified machine instr operand is a vreg, and that
+ /// vreg is being provided by the specified load instruction. If possible,
+ /// try to fold the load as an operand to the instruction, returning true if
+ /// possible.
+ virtual bool TryToFoldLoad(MachineInstr * /*MI*/, unsigned /*OpNo*/,
+ const LoadInst * /*LI*/) {
+ return false;
+ }
+
+ /// recomputeInsertPt - Reset InsertPt to prepare for inserting instructions
+ /// into the current block.
+ void recomputeInsertPt();
+
+ struct SavePoint {
+ MachineBasicBlock::iterator InsertPt;
+ DebugLoc DL;
+ };
+
+ /// enterLocalValueArea - Prepare InsertPt to begin inserting instructions
+ /// into the local value area and return the old insert position.
+ SavePoint enterLocalValueArea();
+
+ /// leaveLocalValueArea - Reset InsertPt to the given old insert position.
+ void leaveLocalValueArea(SavePoint Old);
virtual ~FastISel();
protected:
- explicit FastISel(MachineFunction &mf);
+ explicit FastISel(FunctionLoweringInfo &funcInfo);
+
+ /// TargetSelectInstruction - This method is called by target-independent
+ /// code when the normal FastISel 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;
/// FastEmit_r - This method is called by target-independent code
/// to request that an instruction with the given type and opcode
/// be emitted.
- virtual unsigned FastEmit_(MVT::SimpleValueType VT,
- MVT::SimpleValueType RetVT,
- ISD::NodeType Opcode);
+ virtual unsigned FastEmit_(MVT VT,
+ MVT RetVT,
+ unsigned Opcode);
/// FastEmit_r - This method is called by target-independent code
/// to request that an instruction with the given type, opcode, and
/// register operand be emitted.
///
- virtual unsigned FastEmit_r(MVT::SimpleValueType VT,
- MVT::SimpleValueType RetVT,
- ISD::NodeType Opcode, unsigned Op0);
+ virtual unsigned FastEmit_r(MVT VT,
+ MVT RetVT,
+ unsigned Opcode,
+ unsigned Op0, bool Op0IsKill);
/// FastEmit_rr - This method is called by target-independent code
/// to request that an instruction with the given type, opcode, and
/// register operands be emitted.
///
- virtual unsigned FastEmit_rr(MVT::SimpleValueType VT,
- MVT::SimpleValueType RetVT,
- ISD::NodeType Opcode,
- unsigned Op0, unsigned Op1);
+ virtual unsigned FastEmit_rr(MVT VT,
+ MVT RetVT,
+ unsigned Opcode,
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill);
/// FastEmit_ri - This method is called by target-independent code
/// to request that an instruction with the given type, opcode, and
/// register and immediate operands be emitted.
///
- virtual unsigned FastEmit_ri(MVT::SimpleValueType VT,
- MVT::SimpleValueType RetVT,
- ISD::NodeType Opcode,
- unsigned Op0, uint64_t Imm);
+ virtual unsigned FastEmit_ri(MVT VT,
+ MVT RetVT,
+ unsigned Opcode,
+ unsigned Op0, bool Op0IsKill,
+ uint64_t Imm);
/// FastEmit_rf - This method is called by target-independent code
/// to request that an instruction with the given type, opcode, and
/// register and floating-point immediate operands be emitted.
///
- virtual unsigned FastEmit_rf(MVT::SimpleValueType VT,
- MVT::SimpleValueType RetVT,
- ISD::NodeType Opcode,
- unsigned Op0, ConstantFP *FPImm);
+ virtual unsigned FastEmit_rf(MVT VT,
+ MVT RetVT,
+ unsigned Opcode,
+ unsigned Op0, bool Op0IsKill,
+ const ConstantFP *FPImm);
/// FastEmit_rri - This method is called by target-independent code
/// to request that an instruction with the given type, opcode, and
/// register and immediate operands be emitted.
///
- virtual unsigned FastEmit_rri(MVT::SimpleValueType VT,
- MVT::SimpleValueType RetVT,
- ISD::NodeType Opcode,
- unsigned Op0, unsigned Op1, uint64_t Imm);
+ virtual unsigned FastEmit_rri(MVT VT,
+ MVT RetVT,
+ unsigned Opcode,
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill,
+ uint64_t Imm);
/// FastEmit_ri_ - This method is a wrapper of FastEmit_ri. It first tries
/// to emit an instruction with an immediate operand using FastEmit_ri.
/// If that fails, it materializes the immediate into a register and try
/// FastEmit_rr instead.
- unsigned FastEmit_ri_(MVT::SimpleValueType VT,
- ISD::NodeType Opcode,
- unsigned Op0, uint64_t Imm,
- MVT::SimpleValueType ImmType);
-
- /// FastEmit_rf_ - This method is a wrapper of FastEmit_rf. It first tries
- /// to emit an instruction with an immediate operand using FastEmit_rf.
- /// If that fails, it materializes the immediate into a register and try
- /// FastEmit_rr instead.
- unsigned FastEmit_rf_(MVT::SimpleValueType VT,
- ISD::NodeType Opcode,
- unsigned Op0, ConstantFP *FPImm,
- MVT::SimpleValueType ImmType);
-
+ unsigned FastEmit_ri_(MVT VT,
+ unsigned Opcode,
+ unsigned Op0, bool Op0IsKill,
+ uint64_t Imm, MVT ImmType);
+
/// FastEmit_i - This method is called by target-independent code
/// to request that an instruction with the given type, opcode, and
/// immediate operand be emitted.
- virtual unsigned FastEmit_i(MVT::SimpleValueType VT,
- MVT::SimpleValueType RetVT,
- ISD::NodeType Opcode,
+ virtual unsigned FastEmit_i(MVT VT,
+ MVT RetVT,
+ unsigned Opcode,
uint64_t Imm);
/// FastEmit_f - This method is called by target-independent code
/// to request that an instruction with the given type, opcode, and
/// floating-point immediate operand be emitted.
- virtual unsigned FastEmit_f(MVT::SimpleValueType VT,
- MVT::SimpleValueType RetVT,
- ISD::NodeType Opcode,
- ConstantFP *FPImm);
+ virtual unsigned FastEmit_f(MVT VT,
+ MVT RetVT,
+ unsigned Opcode,
+ const ConstantFP *FPImm);
/// FastEmitInst_ - Emit a MachineInstr with no operands and a
/// result register in the given register class.
///
unsigned FastEmitInst_r(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
- unsigned Op0);
+ unsigned Op0, bool Op0IsKill);
/// FastEmitInst_rr - Emit a MachineInstr with two register operands
/// and a result register in the given register class.
///
unsigned FastEmitInst_rr(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
- unsigned Op0, unsigned Op1);
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill);
- /// FastEmitInst_ri - Emit a MachineInstr with two register operands
+ /// FastEmitInst_rrr - Emit a MachineInstr with three register operands
/// and a result register in the given register class.
///
+ unsigned FastEmitInst_rrr(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill,
+ unsigned Op2, bool Op2IsKill);
+
+ /// FastEmitInst_ri - Emit a MachineInstr with a register operand,
+ /// an immediate, and a result register in the given register class.
+ ///
unsigned FastEmitInst_ri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
- unsigned Op0, uint64_t Imm);
+ unsigned Op0, bool Op0IsKill,
+ uint64_t Imm);
+
+ /// FastEmitInst_rii - Emit a MachineInstr with one register operand
+ /// and two immediate operands.
+ ///
+ unsigned FastEmitInst_rii(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ unsigned Op0, bool Op0IsKill,
+ uint64_t Imm1, uint64_t Imm2);
/// FastEmitInst_rf - Emit a MachineInstr with two register operands
/// and a result register in the given register class.
///
unsigned FastEmitInst_rf(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
- unsigned Op0, ConstantFP *FPImm);
+ unsigned Op0, bool Op0IsKill,
+ const ConstantFP *FPImm);
/// FastEmitInst_rri - Emit a MachineInstr with two register operands,
/// an immediate, and a result register in the given register class.
///
unsigned FastEmitInst_rri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
- unsigned Op0, unsigned Op1, uint64_t Imm);
-
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill,
+ uint64_t Imm);
+
+ /// FastEmitInst_rrii - Emit a MachineInstr with two register operands,
+ /// two immediates operands, and a result register in the given register
+ /// class.
+ unsigned FastEmitInst_rrii(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill,
+ uint64_t Imm1, uint64_t Imm2);
+
/// FastEmitInst_i - Emit a MachineInstr with a single immediate
/// operand, and a result register in the given register class.
unsigned FastEmitInst_i(unsigned MachineInstrOpcode,
const TargetRegisterClass *RC,
uint64_t Imm);
-private:
- unsigned getRegForValue(Value *V,
- DenseMap<const Value*, unsigned> &ValueMap);
+ /// FastEmitInst_ii - Emit a MachineInstr with a two immediate operands.
+ unsigned FastEmitInst_ii(unsigned MachineInstrOpcode,
+ const TargetRegisterClass *RC,
+ uint64_t Imm1, uint64_t Imm2);
+
+ /// FastEmitInst_extractsubreg - Emit a MachineInstr for an extract_subreg
+ /// from a specified index of a superregister to a specified type.
+ unsigned FastEmitInst_extractsubreg(MVT RetVT,
+ unsigned Op0, bool Op0IsKill,
+ uint32_t Idx);
+
+ /// FastEmitZExtFromI1 - Emit MachineInstrs to compute the value of Op
+ /// with all but the least significant bit set to zero.
+ unsigned FastEmitZExtFromI1(MVT VT,
+ unsigned Op0, bool Op0IsKill);
+
+ /// FastEmitBranch - Emit an unconditional branch to the given block,
+ /// unless it is the immediate (fall-through) successor, and update
+ /// the CFG.
+ void FastEmitBranch(MachineBasicBlock *MBB, DebugLoc DL);
+
+ void UpdateValueMap(const Value* I, unsigned Reg, unsigned NumRegs = 1);
unsigned createResultReg(const TargetRegisterClass *RC);
- bool SelectBinaryOp(Instruction *I, ISD::NodeType ISDOpcode,
- DenseMap<const Value*, unsigned> &ValueMap);
+ /// TargetMaterializeConstant - Emit a constant in a register using
+ /// target-specific logic, such as constant pool loads.
+ virtual unsigned TargetMaterializeConstant(const Constant* C) {
+ return 0;
+ }
+
+ /// TargetMaterializeAlloca - Emit an alloca address in a register using
+ /// target-specific logic.
+ virtual unsigned TargetMaterializeAlloca(const AllocaInst* C) {
+ return 0;
+ }
+
+ virtual unsigned TargetMaterializeFloatZero(const ConstantFP* CF) {
+ return 0;
+ }
+
+private:
+ bool SelectBinaryOp(const User *I, unsigned ISDOpcode);
+
+ bool SelectFNeg(const User *I);
+
+ bool SelectGetElementPtr(const User *I);
+
+ bool SelectCall(const User *I);
+
+ bool SelectBitCast(const User *I);
+
+ bool SelectCast(const User *I, unsigned Opcode);
+
+ bool SelectExtractValue(const User *I);
+
+ bool SelectInsertValue(const User *I);
+
+ /// HandlePHINodesInSuccessorBlocks - Handle PHI nodes in successor blocks.
+ /// Emit code to ensure constants are copied into registers when needed.
+ /// Remember the virtual registers that need to be added to the Machine PHI
+ /// nodes as input. We cannot just directly add them, because expansion
+ /// might result in multiple MBB's for one BB. As such, the start of the
+ /// BB might correspond to a different MBB than the end.
+ bool HandlePHINodesInSuccessorBlocks(const BasicBlock *LLVMBB);
+
+ /// materializeRegForValue - Helper for getRegForVale. This function is
+ /// called when the value isn't already available in a register and must
+ /// be materialized with new instructions.
+ unsigned materializeRegForValue(const Value *V, MVT VT);
+
+ /// flushLocalValueMap - clears LocalValueMap and moves the area for the
+ /// new local variables to the beginning of the block. It helps to avoid
+ /// spilling cached variables across heavy instructions like calls.
+ void flushLocalValueMap();
- bool SelectGetElementPtr(Instruction *I,
- DenseMap<const Value*, unsigned> &ValueMap);
+ /// hasTrivialKill - Test whether the given value has exactly one use.
+ bool hasTrivialKill(const Value *V) const;
- bool SelectBitCast(Instruction *I,
- DenseMap<const Value*, unsigned> &ValueMap);
-
- bool SelectCast(Instruction *I, ISD::NodeType Opcode,
- DenseMap<const Value*, unsigned> &ValueMap);
+ /// removeDeadCode - Remove all dead instructions between the I and E.
+ void removeDeadCode(MachineBasicBlock::iterator I,
+ MachineBasicBlock::iterator E);
};
}