-///===-- FastISel.cpp - Implementation of the FastISel class --------------===//
+//===-- FastISel.cpp - Implementation of the FastISel class ---------------===//
//
// The LLVM Compiler Infrastructure
//
//
// This file contains the implementation of the FastISel class.
//
+// "Fast" instruction selection is designed to emit very poor code quickly.
+// Also, it is not designed to be able to do much lowering, so most illegal
+// types (e.g. i64 on 32-bit targets) and operations are not supported. It is
+// also not intended to be able to do much optimization, except in a few cases
+// where doing optimizations reduces overall compile time. For example, folding
+// constants into immediate fields is often done, because it's cheap and it
+// reduces the number of instructions later phases have to examine.
+//
+// "Fast" instruction selection is able to fail gracefully and transfer
+// control to the SelectionDAG selector for operations that it doesn't
+// support. In many cases, this allows us to avoid duplicating a lot of
+// the complicated lowering logic that SelectionDAG currently has.
+//
+// The intended use for "fast" instruction selection is "-O0" mode
+// compilation, where the quality of the generated code is irrelevant when
+// weighed against the speed at which the code can be generated. Also,
+// at -O0, the LLVM optimizers are not running, and this makes the
+// compile time of codegen a much higher portion of the overall compile
+// time. Despite its limitations, "fast" instruction selection is able to
+// handle enough code on its own to provide noticeable overall speedups
+// in -O0 compiles.
+//
+// Basic operations are supported in a target-independent way, by reading
+// the same instruction descriptions that the SelectionDAG selector reads,
+// and identifying simple arithmetic operations that can be directly selected
+// from simple operators. More complicated operations currently require
+// target-specific code.
+//
//===----------------------------------------------------------------------===//
+#define DEBUG_TYPE "isel"
+#include "llvm/Function.h"
+#include "llvm/GlobalVariable.h"
#include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
+#include "llvm/Operator.h"
+#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/FastISel.h"
+#include "llvm/CodeGen/FunctionLoweringInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/Analysis/DebugInfo.h"
+#include "llvm/Analysis/Loads.h"
+#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/ADT/Statistic.h"
using namespace llvm;
-/// SelectBinaryOp - Select and emit code for a binary operator instruction,
-/// which has an opcode which directly corresponds to the given ISD opcode.
+STATISTIC(NumFastIselSuccessIndependent, "Number of insts selected by "
+ "target-independent selector");
+STATISTIC(NumFastIselSuccessTarget, "Number of insts selected by "
+ "target-specific selector");
+STATISTIC(NumFastIselDead, "Number of dead insts removed on failure");
+
+/// startNewBlock - Set the current block to which generated machine
+/// instructions will be appended, and clear the local CSE map.
///
-bool FastISel::SelectBinaryOp(Instruction *I, ISD::NodeType ISDOpcode,
- DenseMap<const Value*, unsigned> &ValueMap) {
- unsigned Op0 = ValueMap[I->getOperand(0)];
- unsigned Op1 = ValueMap[I->getOperand(1)];
- if (Op0 == 0 || Op1 == 0)
- // Unhandled operand. Halt "fast" selection and bail.
+void FastISel::startNewBlock() {
+ LocalValueMap.clear();
+
+ EmitStartPt = 0;
+
+ // Advance the emit start point past any EH_LABEL instructions.
+ MachineBasicBlock::iterator
+ I = FuncInfo.MBB->begin(), E = FuncInfo.MBB->end();
+ while (I != E && I->getOpcode() == TargetOpcode::EH_LABEL) {
+ EmitStartPt = I;
+ ++I;
+ }
+ LastLocalValue = EmitStartPt;
+}
+
+void FastISel::flushLocalValueMap() {
+ LocalValueMap.clear();
+ LastLocalValue = EmitStartPt;
+ recomputeInsertPt();
+}
+
+bool FastISel::hasTrivialKill(const Value *V) const {
+ // Don't consider constants or arguments to have trivial kills.
+ const Instruction *I = dyn_cast<Instruction>(V);
+ if (!I)
return false;
- MVT VT = MVT::getMVT(I->getType(), /*HandleUnknown=*/true);
+ // No-op casts are trivially coalesced by fast-isel.
+ if (const CastInst *Cast = dyn_cast<CastInst>(I))
+ if (Cast->isNoopCast(TD.getIntPtrType(Cast->getContext())) &&
+ !hasTrivialKill(Cast->getOperand(0)))
+ return false;
+
+ // GEPs with all zero indices are trivially coalesced by fast-isel.
+ if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(I))
+ if (GEP->hasAllZeroIndices() && !hasTrivialKill(GEP->getOperand(0)))
+ return false;
+
+ // Only instructions with a single use in the same basic block are considered
+ // to have trivial kills.
+ return I->hasOneUse() &&
+ !(I->getOpcode() == Instruction::BitCast ||
+ I->getOpcode() == Instruction::PtrToInt ||
+ I->getOpcode() == Instruction::IntToPtr) &&
+ cast<Instruction>(*I->use_begin())->getParent() == I->getParent();
+}
+
+unsigned FastISel::getRegForValue(const Value *V) {
+ EVT RealVT = TLI.getValueType(V->getType(), /*AllowUnknown=*/true);
+ // Don't handle non-simple values in FastISel.
+ if (!RealVT.isSimple())
+ return 0;
+
+ // Ignore illegal types. We must do this before looking up the value
+ // in ValueMap because Arguments are given virtual registers regardless
+ // of whether FastISel can handle them.
+ MVT VT = RealVT.getSimpleVT();
+ if (!TLI.isTypeLegal(VT)) {
+ // Handle integer promotions, though, because they're common and easy.
+ if (VT == MVT::i1 || VT == MVT::i8 || VT == MVT::i16)
+ VT = TLI.getTypeToTransformTo(V->getContext(), VT).getSimpleVT();
+ else
+ return 0;
+ }
+
+ // Look up the value to see if we already have a register for it.
+ unsigned Reg = lookUpRegForValue(V);
+ if (Reg != 0)
+ return Reg;
+
+ // In bottom-up mode, just create the virtual register which will be used
+ // to hold the value. It will be materialized later.
+ if (isa<Instruction>(V) &&
+ (!isa<AllocaInst>(V) ||
+ !FuncInfo.StaticAllocaMap.count(cast<AllocaInst>(V))))
+ return FuncInfo.InitializeRegForValue(V);
+
+ SavePoint SaveInsertPt = enterLocalValueArea();
+
+ // Materialize the value in a register. Emit any instructions in the
+ // local value area.
+ Reg = materializeRegForValue(V, VT);
+
+ leaveLocalValueArea(SaveInsertPt);
+
+ return Reg;
+}
+
+/// materializeRegForValue - Helper for getRegForValue. This function is
+/// called when the value isn't already available in a register and must
+/// be materialized with new instructions.
+unsigned FastISel::materializeRegForValue(const Value *V, MVT VT) {
+ unsigned Reg = 0;
+
+ if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
+ if (CI->getValue().getActiveBits() <= 64)
+ Reg = FastEmit_i(VT, VT, ISD::Constant, CI->getZExtValue());
+ } else if (isa<AllocaInst>(V)) {
+ Reg = TargetMaterializeAlloca(cast<AllocaInst>(V));
+ } else if (isa<ConstantPointerNull>(V)) {
+ // Translate this as an integer zero so that it can be
+ // local-CSE'd with actual integer zeros.
+ Reg =
+ getRegForValue(Constant::getNullValue(TD.getIntPtrType(V->getContext())));
+ } else if (const ConstantFP *CF = dyn_cast<ConstantFP>(V)) {
+ if (CF->isNullValue()) {
+ Reg = TargetMaterializeFloatZero(CF);
+ } else {
+ // Try to emit the constant directly.
+ Reg = FastEmit_f(VT, VT, ISD::ConstantFP, CF);
+ }
+
+ if (!Reg) {
+ // Try to emit the constant by using an integer constant with a cast.
+ const APFloat &Flt = CF->getValueAPF();
+ EVT IntVT = TLI.getPointerTy();
+
+ uint64_t x[2];
+ uint32_t IntBitWidth = IntVT.getSizeInBits();
+ bool isExact;
+ (void) Flt.convertToInteger(x, IntBitWidth, /*isSigned=*/true,
+ APFloat::rmTowardZero, &isExact);
+ if (isExact) {
+ APInt IntVal(IntBitWidth, x);
+
+ unsigned IntegerReg =
+ getRegForValue(ConstantInt::get(V->getContext(), IntVal));
+ if (IntegerReg != 0)
+ Reg = FastEmit_r(IntVT.getSimpleVT(), VT, ISD::SINT_TO_FP,
+ IntegerReg, /*Kill=*/false);
+ }
+ }
+ } else if (const Operator *Op = dyn_cast<Operator>(V)) {
+ if (!SelectOperator(Op, Op->getOpcode()))
+ if (!isa<Instruction>(Op) ||
+ !TargetSelectInstruction(cast<Instruction>(Op)))
+ return 0;
+ Reg = lookUpRegForValue(Op);
+ } else if (isa<UndefValue>(V)) {
+ Reg = createResultReg(TLI.getRegClassFor(VT));
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+ TII.get(TargetOpcode::IMPLICIT_DEF), Reg);
+ }
+
+ // If target-independent code couldn't handle the value, give target-specific
+ // code a try.
+ if (!Reg && isa<Constant>(V))
+ Reg = TargetMaterializeConstant(cast<Constant>(V));
+
+ // Don't cache constant materializations in the general ValueMap.
+ // To do so would require tracking what uses they dominate.
+ if (Reg != 0) {
+ LocalValueMap[V] = Reg;
+ LastLocalValue = MRI.getVRegDef(Reg);
+ }
+ return Reg;
+}
+
+unsigned FastISel::lookUpRegForValue(const Value *V) {
+ // Look up the value to see if we already have a register for it. We
+ // cache values defined by Instructions across blocks, and other values
+ // only locally. This is because Instructions already have the SSA
+ // def-dominates-use requirement enforced.
+ DenseMap<const Value *, unsigned>::iterator I = FuncInfo.ValueMap.find(V);
+ if (I != FuncInfo.ValueMap.end())
+ return I->second;
+ return LocalValueMap[V];
+}
+
+/// UpdateValueMap - Update the value map to include the new mapping for this
+/// instruction, or insert an extra copy to get the result in a previous
+/// determined register.
+/// NOTE: This is only necessary because we might select a block that uses
+/// a value before we select the block that defines the value. It might be
+/// possible to fix this by selecting blocks in reverse postorder.
+void FastISel::UpdateValueMap(const Value *I, unsigned Reg, unsigned NumRegs) {
+ if (!isa<Instruction>(I)) {
+ LocalValueMap[I] = Reg;
+ return;
+ }
+
+ unsigned &AssignedReg = FuncInfo.ValueMap[I];
+ if (AssignedReg == 0)
+ // Use the new register.
+ AssignedReg = Reg;
+ else if (Reg != AssignedReg) {
+ // Arrange for uses of AssignedReg to be replaced by uses of Reg.
+ for (unsigned i = 0; i < NumRegs; i++)
+ FuncInfo.RegFixups[AssignedReg+i] = Reg+i;
+
+ AssignedReg = Reg;
+ }
+}
+
+std::pair<unsigned, bool> FastISel::getRegForGEPIndex(const Value *Idx) {
+ unsigned IdxN = getRegForValue(Idx);
+ if (IdxN == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return std::pair<unsigned, bool>(0, false);
+
+ bool IdxNIsKill = hasTrivialKill(Idx);
+
+ // If the index is smaller or larger than intptr_t, truncate or extend it.
+ MVT PtrVT = TLI.getPointerTy();
+ EVT IdxVT = EVT::getEVT(Idx->getType(), /*HandleUnknown=*/false);
+ if (IdxVT.bitsLT(PtrVT)) {
+ IdxN = FastEmit_r(IdxVT.getSimpleVT(), PtrVT, ISD::SIGN_EXTEND,
+ IdxN, IdxNIsKill);
+ IdxNIsKill = true;
+ }
+ else if (IdxVT.bitsGT(PtrVT)) {
+ IdxN = FastEmit_r(IdxVT.getSimpleVT(), PtrVT, ISD::TRUNCATE,
+ IdxN, IdxNIsKill);
+ IdxNIsKill = true;
+ }
+ return std::pair<unsigned, bool>(IdxN, IdxNIsKill);
+}
+
+void FastISel::recomputeInsertPt() {
+ if (getLastLocalValue()) {
+ FuncInfo.InsertPt = getLastLocalValue();
+ FuncInfo.MBB = FuncInfo.InsertPt->getParent();
+ ++FuncInfo.InsertPt;
+ } else
+ FuncInfo.InsertPt = FuncInfo.MBB->getFirstNonPHI();
+
+ // Now skip past any EH_LABELs, which must remain at the beginning.
+ while (FuncInfo.InsertPt != FuncInfo.MBB->end() &&
+ FuncInfo.InsertPt->getOpcode() == TargetOpcode::EH_LABEL)
+ ++FuncInfo.InsertPt;
+}
+
+void FastISel::removeDeadCode(MachineBasicBlock::iterator I,
+ MachineBasicBlock::iterator E) {
+ assert (I && E && std::distance(I, E) > 0 && "Invalid iterator!");
+ while (I != E) {
+ MachineInstr *Dead = &*I;
+ ++I;
+ Dead->eraseFromParent();
+ ++NumFastIselDead;
+ }
+ recomputeInsertPt();
+}
+
+FastISel::SavePoint FastISel::enterLocalValueArea() {
+ MachineBasicBlock::iterator OldInsertPt = FuncInfo.InsertPt;
+ DebugLoc OldDL = DL;
+ recomputeInsertPt();
+ DL = DebugLoc();
+ SavePoint SP = { OldInsertPt, OldDL };
+ return SP;
+}
+
+void FastISel::leaveLocalValueArea(SavePoint OldInsertPt) {
+ if (FuncInfo.InsertPt != FuncInfo.MBB->begin())
+ LastLocalValue = llvm::prior(FuncInfo.InsertPt);
+
+ // Restore the previous insert position.
+ FuncInfo.InsertPt = OldInsertPt.InsertPt;
+ DL = OldInsertPt.DL;
+}
+
+/// SelectBinaryOp - Select and emit code for a binary operator instruction,
+/// which has an opcode which directly corresponds to the given ISD opcode.
+///
+bool FastISel::SelectBinaryOp(const User *I, unsigned ISDOpcode) {
+ EVT VT = EVT::getEVT(I->getType(), /*HandleUnknown=*/true);
if (VT == MVT::Other || !VT.isSimple())
// Unhandled type. Halt "fast" selection and bail.
return false;
- unsigned ResultReg = FastEmit_rr(VT.getSimpleVT(), ISDOpcode, Op0, Op1);
+ // We only handle legal types. For example, on x86-32 the instruction
+ // selector contains all of the 64-bit instructions from x86-64,
+ // under the assumption that i64 won't be used if the target doesn't
+ // support it.
+ if (!TLI.isTypeLegal(VT)) {
+ // MVT::i1 is special. Allow AND, OR, or XOR because they
+ // don't require additional zeroing, which makes them easy.
+ if (VT == MVT::i1 &&
+ (ISDOpcode == ISD::AND || ISDOpcode == ISD::OR ||
+ ISDOpcode == ISD::XOR))
+ VT = TLI.getTypeToTransformTo(I->getContext(), VT);
+ else
+ return false;
+ }
+
+ // Check if the first operand is a constant, and handle it as "ri". At -O0,
+ // we don't have anything that canonicalizes operand order.
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(0)))
+ if (isa<Instruction>(I) && cast<Instruction>(I)->isCommutative()) {
+ unsigned Op1 = getRegForValue(I->getOperand(1));
+ if (Op1 == 0) return false;
+
+ bool Op1IsKill = hasTrivialKill(I->getOperand(1));
+
+ unsigned ResultReg = FastEmit_ri_(VT.getSimpleVT(), ISDOpcode, Op1,
+ Op1IsKill, CI->getZExtValue(),
+ VT.getSimpleVT());
+ if (ResultReg == 0) return false;
+
+ // We successfully emitted code for the given LLVM Instruction.
+ UpdateValueMap(I, ResultReg);
+ return true;
+ }
+
+
+ unsigned Op0 = getRegForValue(I->getOperand(0));
+ if (Op0 == 0) // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+
+ bool Op0IsKill = hasTrivialKill(I->getOperand(0));
+
+ // Check if the second operand is a constant and handle it appropriately.
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1))) {
+ uint64_t Imm = CI->getZExtValue();
+
+ // Transform "sdiv exact X, 8" -> "sra X, 3".
+ if (ISDOpcode == ISD::SDIV && isa<BinaryOperator>(I) &&
+ cast<BinaryOperator>(I)->isExact() &&
+ isPowerOf2_64(Imm)) {
+ Imm = Log2_64(Imm);
+ ISDOpcode = ISD::SRA;
+ }
+
+ // Transform "urem x, pow2" -> "and x, pow2-1".
+ if (ISDOpcode == ISD::UREM && isa<BinaryOperator>(I) &&
+ isPowerOf2_64(Imm)) {
+ --Imm;
+ ISDOpcode = ISD::AND;
+ }
+
+ unsigned ResultReg = FastEmit_ri_(VT.getSimpleVT(), ISDOpcode, Op0,
+ Op0IsKill, Imm, VT.getSimpleVT());
+ if (ResultReg == 0) return false;
+
+ // We successfully emitted code for the given LLVM Instruction.
+ UpdateValueMap(I, ResultReg);
+ return true;
+ }
+
+ // Check if the second operand is a constant float.
+ if (ConstantFP *CF = dyn_cast<ConstantFP>(I->getOperand(1))) {
+ unsigned ResultReg = FastEmit_rf(VT.getSimpleVT(), VT.getSimpleVT(),
+ ISDOpcode, Op0, Op0IsKill, CF);
+ if (ResultReg != 0) {
+ // We successfully emitted code for the given LLVM Instruction.
+ UpdateValueMap(I, ResultReg);
+ return true;
+ }
+ }
+
+ unsigned Op1 = getRegForValue(I->getOperand(1));
+ if (Op1 == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+
+ bool Op1IsKill = hasTrivialKill(I->getOperand(1));
+
+ // Now we have both operands in registers. Emit the instruction.
+ unsigned ResultReg = FastEmit_rr(VT.getSimpleVT(), VT.getSimpleVT(),
+ ISDOpcode,
+ Op0, Op0IsKill,
+ Op1, Op1IsKill);
if (ResultReg == 0)
// Target-specific code wasn't able to find a machine opcode for
// the given ISD opcode and type. Halt "fast" selection and bail.
return false;
// We successfully emitted code for the given LLVM Instruction.
- ValueMap[I] = ResultReg;
+ UpdateValueMap(I, ResultReg);
return true;
}
-bool FastISel::SelectGetElementPtr(Instruction *I,
- DenseMap<const Value*, unsigned> &ValueMap) {
- // TODO: implement me
- return false;
+bool FastISel::SelectGetElementPtr(const User *I) {
+ unsigned N = getRegForValue(I->getOperand(0));
+ if (N == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+
+ bool NIsKill = hasTrivialKill(I->getOperand(0));
+
+ // Keep a running tab of the total offset to coalesce multiple N = N + Offset
+ // into a single N = N + TotalOffset.
+ uint64_t TotalOffs = 0;
+ // FIXME: What's a good SWAG number for MaxOffs?
+ uint64_t MaxOffs = 2048;
+ Type *Ty = I->getOperand(0)->getType();
+ MVT VT = TLI.getPointerTy();
+ for (GetElementPtrInst::const_op_iterator OI = I->op_begin()+1,
+ E = I->op_end(); OI != E; ++OI) {
+ const Value *Idx = *OI;
+ if (StructType *StTy = dyn_cast<StructType>(Ty)) {
+ unsigned Field = cast<ConstantInt>(Idx)->getZExtValue();
+ if (Field) {
+ // N = N + Offset
+ TotalOffs += TD.getStructLayout(StTy)->getElementOffset(Field);
+ if (TotalOffs >= MaxOffs) {
+ N = FastEmit_ri_(VT, ISD::ADD, N, NIsKill, TotalOffs, VT);
+ if (N == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+ NIsKill = true;
+ TotalOffs = 0;
+ }
+ }
+ Ty = StTy->getElementType(Field);
+ } else {
+ Ty = cast<SequentialType>(Ty)->getElementType();
+
+ // If this is a constant subscript, handle it quickly.
+ if (const ConstantInt *CI = dyn_cast<ConstantInt>(Idx)) {
+ if (CI->isZero()) continue;
+ // N = N + Offset
+ TotalOffs +=
+ TD.getTypeAllocSize(Ty)*cast<ConstantInt>(CI)->getSExtValue();
+ if (TotalOffs >= MaxOffs) {
+ N = FastEmit_ri_(VT, ISD::ADD, N, NIsKill, TotalOffs, VT);
+ if (N == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+ NIsKill = true;
+ TotalOffs = 0;
+ }
+ continue;
+ }
+ if (TotalOffs) {
+ N = FastEmit_ri_(VT, ISD::ADD, N, NIsKill, TotalOffs, VT);
+ if (N == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+ NIsKill = true;
+ TotalOffs = 0;
+ }
+
+ // N = N + Idx * ElementSize;
+ uint64_t ElementSize = TD.getTypeAllocSize(Ty);
+ std::pair<unsigned, bool> Pair = getRegForGEPIndex(Idx);
+ unsigned IdxN = Pair.first;
+ bool IdxNIsKill = Pair.second;
+ if (IdxN == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+
+ if (ElementSize != 1) {
+ IdxN = FastEmit_ri_(VT, ISD::MUL, IdxN, IdxNIsKill, ElementSize, VT);
+ if (IdxN == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+ IdxNIsKill = true;
+ }
+ N = FastEmit_rr(VT, VT, ISD::ADD, N, NIsKill, IdxN, IdxNIsKill);
+ if (N == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+ }
+ }
+ if (TotalOffs) {
+ N = FastEmit_ri_(VT, ISD::ADD, N, NIsKill, TotalOffs, VT);
+ if (N == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+ }
+
+ // We successfully emitted code for the given LLVM Instruction.
+ UpdateValueMap(I, N);
+ return true;
}
-BasicBlock::iterator
-FastISel::SelectInstructions(BasicBlock::iterator Begin,
- BasicBlock::iterator End,
- DenseMap<const Value*, unsigned> &ValueMap) {
- BasicBlock::iterator I = Begin;
+bool FastISel::SelectCall(const User *I) {
+ const CallInst *Call = cast<CallInst>(I);
+
+ // Handle simple inline asms.
+ if (const InlineAsm *IA = dyn_cast<InlineAsm>(Call->getCalledValue())) {
+ // Don't attempt to handle constraints.
+ if (!IA->getConstraintString().empty())
+ return false;
+
+ unsigned ExtraInfo = 0;
+ if (IA->hasSideEffects())
+ ExtraInfo |= InlineAsm::Extra_HasSideEffects;
+ if (IA->isAlignStack())
+ ExtraInfo |= InlineAsm::Extra_IsAlignStack;
+
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+ TII.get(TargetOpcode::INLINEASM))
+ .addExternalSymbol(IA->getAsmString().c_str())
+ .addImm(ExtraInfo);
+ return true;
+ }
+
+ MachineModuleInfo &MMI = FuncInfo.MF->getMMI();
+ ComputeUsesVAFloatArgument(*Call, &MMI);
+
+ const Function *F = Call->getCalledFunction();
+ if (!F) return false;
- for (; I != End; ++I) {
- switch (I->getOpcode()) {
- case Instruction::Add: {
- ISD::NodeType Opc = I->getType()->isFPOrFPVector() ? ISD::FADD : ISD::ADD;
- if (!SelectBinaryOp(I, Opc, ValueMap)) return I; break;
+ // Handle selected intrinsic function calls.
+ switch (F->getIntrinsicID()) {
+ default: break;
+ // At -O0 we don't care about the lifetime intrinsics.
+ case Intrinsic::lifetime_start:
+ case Intrinsic::lifetime_end:
+ return true;
+ case Intrinsic::dbg_declare: {
+ const DbgDeclareInst *DI = cast<DbgDeclareInst>(Call);
+ if (!DIVariable(DI->getVariable()).Verify() ||
+ !FuncInfo.MF->getMMI().hasDebugInfo()) {
+ DEBUG(dbgs() << "Dropping debug info for " << *DI << "\n");
+ return true;
}
- case Instruction::Sub: {
- ISD::NodeType Opc = I->getType()->isFPOrFPVector() ? ISD::FSUB : ISD::SUB;
- if (!SelectBinaryOp(I, Opc, ValueMap)) return I; break;
+
+ const Value *Address = DI->getAddress();
+ if (!Address || isa<UndefValue>(Address)) {
+ DEBUG(dbgs() << "Dropping debug info for " << *DI << "\n");
+ return true;
}
- case Instruction::Mul: {
- ISD::NodeType Opc = I->getType()->isFPOrFPVector() ? ISD::FMUL : ISD::MUL;
- if (!SelectBinaryOp(I, Opc, ValueMap)) return I; break;
+
+ unsigned Reg = 0;
+ unsigned Offset = 0;
+ if (const Argument *Arg = dyn_cast<Argument>(Address)) {
+ // Some arguments' frame index is recorded during argument lowering.
+ Offset = FuncInfo.getArgumentFrameIndex(Arg);
+ if (Offset)
+ Reg = TRI.getFrameRegister(*FuncInfo.MF);
}
- case Instruction::SDiv:
- if (!SelectBinaryOp(I, ISD::SDIV, ValueMap)) return I; break;
- case Instruction::UDiv:
- if (!SelectBinaryOp(I, ISD::UDIV, ValueMap)) return I; break;
- case Instruction::FDiv:
- if (!SelectBinaryOp(I, ISD::FDIV, ValueMap)) return I; break;
- case Instruction::SRem:
- if (!SelectBinaryOp(I, ISD::SREM, ValueMap)) return I; break;
- case Instruction::URem:
- if (!SelectBinaryOp(I, ISD::UREM, ValueMap)) return I; break;
- case Instruction::FRem:
- if (!SelectBinaryOp(I, ISD::FREM, ValueMap)) return I; break;
- case Instruction::Shl:
- if (!SelectBinaryOp(I, ISD::SHL, ValueMap)) return I; break;
- case Instruction::LShr:
- if (!SelectBinaryOp(I, ISD::SRL, ValueMap)) return I; break;
- case Instruction::AShr:
- if (!SelectBinaryOp(I, ISD::SRA, ValueMap)) return I; break;
- case Instruction::And:
- if (!SelectBinaryOp(I, ISD::AND, ValueMap)) return I; break;
- case Instruction::Or:
- if (!SelectBinaryOp(I, ISD::OR, ValueMap)) return I; break;
- case Instruction::Xor:
- if (!SelectBinaryOp(I, ISD::XOR, ValueMap)) return I; break;
-
- case Instruction::GetElementPtr:
- if (!SelectGetElementPtr(I, ValueMap)) return I;
- break;
-
- case Instruction::Br: {
- BranchInst *BI = cast<BranchInst>(I);
-
- // For now, check for and handle just the most trivial case: an
- // unconditional fall-through branch.
- if (BI->isUnconditional()) {
- MachineFunction::iterator NextMBB =
- next(MachineFunction::iterator(MBB));
- if (NextMBB != MF->end() &&
- NextMBB->getBasicBlock() == BI->getSuccessor(0)) {
- MBB->addSuccessor(NextMBB);
- break;
- }
- }
+ if (!Reg)
+ Reg = lookUpRegForValue(Address);
+
+ if (!Reg && isa<Instruction>(Address) &&
+ (!isa<AllocaInst>(Address) ||
+ !FuncInfo.StaticAllocaMap.count(cast<AllocaInst>(Address))))
+ Reg = FuncInfo.InitializeRegForValue(Address);
+
+ if (Reg)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+ TII.get(TargetOpcode::DBG_VALUE))
+ .addReg(Reg, RegState::Debug).addImm(Offset)
+ .addMetadata(DI->getVariable());
+ else
+ // We can't yet handle anything else here because it would require
+ // generating code, thus altering codegen because of debug info.
+ DEBUG(dbgs() << "Dropping debug info for " << DI);
+ return true;
+ }
+ case Intrinsic::dbg_value: {
+ // This form of DBG_VALUE is target-independent.
+ const DbgValueInst *DI = cast<DbgValueInst>(Call);
+ const MCInstrDesc &II = TII.get(TargetOpcode::DBG_VALUE);
+ const Value *V = DI->getValue();
+ if (!V) {
+ // Currently the optimizer can produce this; insert an undef to
+ // help debugging. Probably the optimizer should not do this.
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(0U).addImm(DI->getOffset())
+ .addMetadata(DI->getVariable());
+ } else if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
+ if (CI->getBitWidth() > 64)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addCImm(CI).addImm(DI->getOffset())
+ .addMetadata(DI->getVariable());
+ else
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addImm(CI->getZExtValue()).addImm(DI->getOffset())
+ .addMetadata(DI->getVariable());
+ } else if (const ConstantFP *CF = dyn_cast<ConstantFP>(V)) {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addFPImm(CF).addImm(DI->getOffset())
+ .addMetadata(DI->getVariable());
+ } else if (unsigned Reg = lookUpRegForValue(V)) {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(Reg, RegState::Debug).addImm(DI->getOffset())
+ .addMetadata(DI->getVariable());
+ } else {
+ // We can't yet handle anything else here because it would require
+ // generating code, thus altering codegen because of debug info.
+ DEBUG(dbgs() << "Dropping debug info for " << DI);
+ }
+ return true;
+ }
+ case Intrinsic::objectsize: {
+ ConstantInt *CI = cast<ConstantInt>(Call->getArgOperand(1));
+ unsigned long long Res = CI->isZero() ? -1ULL : 0;
+ Constant *ResCI = ConstantInt::get(Call->getType(), Res);
+ unsigned ResultReg = getRegForValue(ResCI);
+ if (ResultReg == 0)
+ return false;
+ UpdateValueMap(Call, ResultReg);
+ return true;
+ }
+ }
+
+ // Usually, it does not make sense to initialize a value,
+ // make an unrelated function call and use the value, because
+ // it tends to be spilled on the stack. So, we move the pointer
+ // to the last local value to the beginning of the block, so that
+ // all the values which have already been materialized,
+ // appear after the call. It also makes sense to skip intrinsics
+ // since they tend to be inlined.
+ if (!isa<IntrinsicInst>(F))
+ flushLocalValueMap();
+
+ // An arbitrary call. Bail.
+ return false;
+}
+
+bool FastISel::SelectCast(const User *I, unsigned Opcode) {
+ EVT SrcVT = TLI.getValueType(I->getOperand(0)->getType());
+ EVT DstVT = TLI.getValueType(I->getType());
+
+ if (SrcVT == MVT::Other || !SrcVT.isSimple() ||
+ DstVT == MVT::Other || !DstVT.isSimple())
+ // Unhandled type. Halt "fast" selection and bail.
+ return false;
+
+ // Check if the destination type is legal.
+ if (!TLI.isTypeLegal(DstVT))
+ return false;
+
+ // Check if the source operand is legal.
+ if (!TLI.isTypeLegal(SrcVT))
+ return false;
+
+ unsigned InputReg = getRegForValue(I->getOperand(0));
+ if (!InputReg)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
+
+ bool InputRegIsKill = hasTrivialKill(I->getOperand(0));
+
+ unsigned ResultReg = FastEmit_r(SrcVT.getSimpleVT(),
+ DstVT.getSimpleVT(),
+ Opcode,
+ InputReg, InputRegIsKill);
+ if (!ResultReg)
+ return false;
+
+ UpdateValueMap(I, ResultReg);
+ return true;
+}
+
+bool FastISel::SelectBitCast(const User *I) {
+ // If the bitcast doesn't change the type, just use the operand value.
+ if (I->getType() == I->getOperand(0)->getType()) {
+ unsigned Reg = getRegForValue(I->getOperand(0));
+ if (Reg == 0)
+ return false;
+ UpdateValueMap(I, Reg);
+ return true;
+ }
+
+ // Bitcasts of other values become reg-reg copies or BITCAST operators.
+ EVT SrcVT = TLI.getValueType(I->getOperand(0)->getType());
+ EVT DstVT = TLI.getValueType(I->getType());
+
+ if (SrcVT == MVT::Other || !SrcVT.isSimple() ||
+ DstVT == MVT::Other || !DstVT.isSimple() ||
+ !TLI.isTypeLegal(SrcVT) || !TLI.isTypeLegal(DstVT))
+ // Unhandled type. Halt "fast" selection and bail.
+ return false;
+
+ unsigned Op0 = getRegForValue(I->getOperand(0));
+ if (Op0 == 0)
+ // Unhandled operand. Halt "fast" selection and bail.
+ return false;
- // Something more complicated. Halt "fast" selection and bail.
- return I;
+ bool Op0IsKill = hasTrivialKill(I->getOperand(0));
+
+ // First, try to perform the bitcast by inserting a reg-reg copy.
+ unsigned ResultReg = 0;
+ if (SrcVT.getSimpleVT() == DstVT.getSimpleVT()) {
+ const TargetRegisterClass* SrcClass = TLI.getRegClassFor(SrcVT);
+ const TargetRegisterClass* DstClass = TLI.getRegClassFor(DstVT);
+ // Don't attempt a cross-class copy. It will likely fail.
+ if (SrcClass == DstClass) {
+ ResultReg = createResultReg(DstClass);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(Op0);
}
- default:
- // Unhandled instruction. Halt "fast" selection and bail.
- return I;
+ }
+
+ // If the reg-reg copy failed, select a BITCAST opcode.
+ if (!ResultReg)
+ ResultReg = FastEmit_r(SrcVT.getSimpleVT(), DstVT.getSimpleVT(),
+ ISD::BITCAST, Op0, Op0IsKill);
+
+ if (!ResultReg)
+ return false;
+
+ UpdateValueMap(I, ResultReg);
+ return true;
+}
+
+bool
+FastISel::SelectInstruction(const Instruction *I) {
+ // Just before the terminator instruction, insert instructions to
+ // feed PHI nodes in successor blocks.
+ if (isa<TerminatorInst>(I))
+ if (!HandlePHINodesInSuccessorBlocks(I->getParent()))
+ return false;
+
+ DL = I->getDebugLoc();
+
+ MachineBasicBlock::iterator SavedInsertPt = FuncInfo.InsertPt;
+
+ // First, try doing target-independent selection.
+ if (SelectOperator(I, I->getOpcode())) {
+ ++NumFastIselSuccessIndependent;
+ DL = DebugLoc();
+ return true;
+ }
+ // Remove dead code. However, ignore call instructions since we've flushed
+ // the local value map and recomputed the insert point.
+ if (!isa<CallInst>(I)) {
+ recomputeInsertPt();
+ if (SavedInsertPt != FuncInfo.InsertPt)
+ removeDeadCode(FuncInfo.InsertPt, SavedInsertPt);
+ }
+
+ // Next, try calling the target to attempt to handle the instruction.
+ SavedInsertPt = FuncInfo.InsertPt;
+ if (TargetSelectInstruction(I)) {
+ ++NumFastIselSuccessTarget;
+ DL = DebugLoc();
+ return true;
+ }
+ // Check for dead code and remove as necessary.
+ recomputeInsertPt();
+ if (SavedInsertPt != FuncInfo.InsertPt)
+ removeDeadCode(FuncInfo.InsertPt, SavedInsertPt);
+
+ DL = DebugLoc();
+ return false;
+}
+
+/// FastEmitBranch - Emit an unconditional branch to the given block,
+/// unless it is the immediate (fall-through) successor, and update
+/// the CFG.
+void
+FastISel::FastEmitBranch(MachineBasicBlock *MSucc, DebugLoc DL) {
+ if (FuncInfo.MBB->isLayoutSuccessor(MSucc)) {
+ // The unconditional fall-through case, which needs no instructions.
+ } else {
+ // The unconditional branch case.
+ TII.InsertBranch(*FuncInfo.MBB, MSucc, NULL,
+ SmallVector<MachineOperand, 0>(), DL);
+ }
+ FuncInfo.MBB->addSuccessor(MSucc);
+}
+
+/// SelectFNeg - Emit an FNeg operation.
+///
+bool
+FastISel::SelectFNeg(const User *I) {
+ unsigned OpReg = getRegForValue(BinaryOperator::getFNegArgument(I));
+ if (OpReg == 0) return false;
+
+ bool OpRegIsKill = hasTrivialKill(I);
+
+ // If the target has ISD::FNEG, use it.
+ EVT VT = TLI.getValueType(I->getType());
+ unsigned ResultReg = FastEmit_r(VT.getSimpleVT(), VT.getSimpleVT(),
+ ISD::FNEG, OpReg, OpRegIsKill);
+ if (ResultReg != 0) {
+ UpdateValueMap(I, ResultReg);
+ return true;
+ }
+
+ // Bitcast the value to integer, twiddle the sign bit with xor,
+ // and then bitcast it back to floating-point.
+ if (VT.getSizeInBits() > 64) return false;
+ EVT IntVT = EVT::getIntegerVT(I->getContext(), VT.getSizeInBits());
+ if (!TLI.isTypeLegal(IntVT))
+ return false;
+
+ unsigned IntReg = FastEmit_r(VT.getSimpleVT(), IntVT.getSimpleVT(),
+ ISD::BITCAST, OpReg, OpRegIsKill);
+ if (IntReg == 0)
+ return false;
+
+ unsigned IntResultReg = FastEmit_ri_(IntVT.getSimpleVT(), ISD::XOR,
+ IntReg, /*Kill=*/true,
+ UINT64_C(1) << (VT.getSizeInBits()-1),
+ IntVT.getSimpleVT());
+ if (IntResultReg == 0)
+ return false;
+
+ ResultReg = FastEmit_r(IntVT.getSimpleVT(), VT.getSimpleVT(),
+ ISD::BITCAST, IntResultReg, /*Kill=*/true);
+ if (ResultReg == 0)
+ return false;
+
+ UpdateValueMap(I, ResultReg);
+ return true;
+}
+
+bool
+FastISel::SelectExtractValue(const User *U) {
+ const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(U);
+ if (!EVI)
+ return false;
+
+ // Make sure we only try to handle extracts with a legal result. But also
+ // allow i1 because it's easy.
+ EVT RealVT = TLI.getValueType(EVI->getType(), /*AllowUnknown=*/true);
+ if (!RealVT.isSimple())
+ return false;
+ MVT VT = RealVT.getSimpleVT();
+ if (!TLI.isTypeLegal(VT) && VT != MVT::i1)
+ return false;
+
+ const Value *Op0 = EVI->getOperand(0);
+ Type *AggTy = Op0->getType();
+
+ // Get the base result register.
+ unsigned ResultReg;
+ DenseMap<const Value *, unsigned>::iterator I = FuncInfo.ValueMap.find(Op0);
+ if (I != FuncInfo.ValueMap.end())
+ ResultReg = I->second;
+ else if (isa<Instruction>(Op0))
+ ResultReg = FuncInfo.InitializeRegForValue(Op0);
+ else
+ return false; // fast-isel can't handle aggregate constants at the moment
+
+ // Get the actual result register, which is an offset from the base register.
+ unsigned VTIndex = ComputeLinearIndex(AggTy, EVI->getIndices());
+
+ SmallVector<EVT, 4> AggValueVTs;
+ ComputeValueVTs(TLI, AggTy, AggValueVTs);
+
+ for (unsigned i = 0; i < VTIndex; i++)
+ ResultReg += TLI.getNumRegisters(FuncInfo.Fn->getContext(), AggValueVTs[i]);
+
+ UpdateValueMap(EVI, ResultReg);
+ return true;
+}
+
+bool
+FastISel::SelectOperator(const User *I, unsigned Opcode) {
+ switch (Opcode) {
+ case Instruction::Add:
+ return SelectBinaryOp(I, ISD::ADD);
+ case Instruction::FAdd:
+ return SelectBinaryOp(I, ISD::FADD);
+ case Instruction::Sub:
+ return SelectBinaryOp(I, ISD::SUB);
+ case Instruction::FSub:
+ // FNeg is currently represented in LLVM IR as a special case of FSub.
+ if (BinaryOperator::isFNeg(I))
+ return SelectFNeg(I);
+ return SelectBinaryOp(I, ISD::FSUB);
+ case Instruction::Mul:
+ return SelectBinaryOp(I, ISD::MUL);
+ case Instruction::FMul:
+ return SelectBinaryOp(I, ISD::FMUL);
+ case Instruction::SDiv:
+ return SelectBinaryOp(I, ISD::SDIV);
+ case Instruction::UDiv:
+ return SelectBinaryOp(I, ISD::UDIV);
+ case Instruction::FDiv:
+ return SelectBinaryOp(I, ISD::FDIV);
+ case Instruction::SRem:
+ return SelectBinaryOp(I, ISD::SREM);
+ case Instruction::URem:
+ return SelectBinaryOp(I, ISD::UREM);
+ case Instruction::FRem:
+ return SelectBinaryOp(I, ISD::FREM);
+ case Instruction::Shl:
+ return SelectBinaryOp(I, ISD::SHL);
+ case Instruction::LShr:
+ return SelectBinaryOp(I, ISD::SRL);
+ case Instruction::AShr:
+ return SelectBinaryOp(I, ISD::SRA);
+ case Instruction::And:
+ return SelectBinaryOp(I, ISD::AND);
+ case Instruction::Or:
+ return SelectBinaryOp(I, ISD::OR);
+ case Instruction::Xor:
+ return SelectBinaryOp(I, ISD::XOR);
+
+ case Instruction::GetElementPtr:
+ return SelectGetElementPtr(I);
+
+ case Instruction::Br: {
+ const BranchInst *BI = cast<BranchInst>(I);
+
+ if (BI->isUnconditional()) {
+ const BasicBlock *LLVMSucc = BI->getSuccessor(0);
+ MachineBasicBlock *MSucc = FuncInfo.MBBMap[LLVMSucc];
+ FastEmitBranch(MSucc, BI->getDebugLoc());
+ return true;
}
+
+ // Conditional branches are not handed yet.
+ // Halt "fast" selection and bail.
+ return false;
}
- return I;
+ case Instruction::Unreachable:
+ // Nothing to emit.
+ return true;
+
+ case Instruction::Alloca:
+ // FunctionLowering has the static-sized case covered.
+ if (FuncInfo.StaticAllocaMap.count(cast<AllocaInst>(I)))
+ return true;
+
+ // Dynamic-sized alloca is not handled yet.
+ return false;
+
+ case Instruction::Call:
+ return SelectCall(I);
+
+ case Instruction::BitCast:
+ return SelectBitCast(I);
+
+ case Instruction::FPToSI:
+ return SelectCast(I, ISD::FP_TO_SINT);
+ case Instruction::ZExt:
+ return SelectCast(I, ISD::ZERO_EXTEND);
+ case Instruction::SExt:
+ return SelectCast(I, ISD::SIGN_EXTEND);
+ case Instruction::Trunc:
+ return SelectCast(I, ISD::TRUNCATE);
+ case Instruction::SIToFP:
+ return SelectCast(I, ISD::SINT_TO_FP);
+
+ case Instruction::IntToPtr: // Deliberate fall-through.
+ case Instruction::PtrToInt: {
+ EVT SrcVT = TLI.getValueType(I->getOperand(0)->getType());
+ EVT DstVT = TLI.getValueType(I->getType());
+ if (DstVT.bitsGT(SrcVT))
+ return SelectCast(I, ISD::ZERO_EXTEND);
+ if (DstVT.bitsLT(SrcVT))
+ return SelectCast(I, ISD::TRUNCATE);
+ unsigned Reg = getRegForValue(I->getOperand(0));
+ if (Reg == 0) return false;
+ UpdateValueMap(I, Reg);
+ return true;
+ }
+
+ case Instruction::ExtractValue:
+ return SelectExtractValue(I);
+
+ case Instruction::PHI:
+ llvm_unreachable("FastISel shouldn't visit PHI nodes!");
+
+ default:
+ // Unhandled instruction. Halt "fast" selection and bail.
+ return false;
+ }
+}
+
+FastISel::FastISel(FunctionLoweringInfo &funcInfo)
+ : FuncInfo(funcInfo),
+ MRI(FuncInfo.MF->getRegInfo()),
+ MFI(*FuncInfo.MF->getFrameInfo()),
+ MCP(*FuncInfo.MF->getConstantPool()),
+ TM(FuncInfo.MF->getTarget()),
+ TD(*TM.getTargetData()),
+ TII(*TM.getInstrInfo()),
+ TLI(*TM.getTargetLowering()),
+ TRI(*TM.getRegisterInfo()) {
}
FastISel::~FastISel() {}
-unsigned FastISel::FastEmit_(MVT::SimpleValueType, ISD::NodeType) {
+unsigned FastISel::FastEmit_(MVT, MVT,
+ unsigned) {
return 0;
}
-unsigned FastISel::FastEmit_r(MVT::SimpleValueType, ISD::NodeType,
- unsigned /*Op0*/) {
+unsigned FastISel::FastEmit_r(MVT, MVT,
+ unsigned,
+ unsigned /*Op0*/, bool /*Op0IsKill*/) {
return 0;
}
-unsigned FastISel::FastEmit_rr(MVT::SimpleValueType, ISD::NodeType,
- unsigned /*Op0*/, unsigned /*Op0*/) {
+unsigned FastISel::FastEmit_rr(MVT, MVT,
+ unsigned,
+ unsigned /*Op0*/, bool /*Op0IsKill*/,
+ unsigned /*Op1*/, bool /*Op1IsKill*/) {
return 0;
}
-unsigned FastISel::FastEmitInst_(unsigned MachineInstOpcode,
- const TargetRegisterClass* RC) {
- MachineRegisterInfo &MRI = MF->getRegInfo();
- const TargetInstrDesc &II = TII->get(MachineInstOpcode);
- unsigned ResultReg = MRI.createVirtualRegister(RC);
+unsigned FastISel::FastEmit_i(MVT, MVT, unsigned, uint64_t /*Imm*/) {
+ return 0;
+}
+
+unsigned FastISel::FastEmit_f(MVT, MVT,
+ unsigned, const ConstantFP * /*FPImm*/) {
+ return 0;
+}
- MachineInstr *MI = BuildMI(*MF, II, ResultReg);
+unsigned FastISel::FastEmit_ri(MVT, MVT,
+ unsigned,
+ unsigned /*Op0*/, bool /*Op0IsKill*/,
+ uint64_t /*Imm*/) {
+ return 0;
+}
- MBB->push_back(MI);
+unsigned FastISel::FastEmit_rf(MVT, MVT,
+ unsigned,
+ unsigned /*Op0*/, bool /*Op0IsKill*/,
+ const ConstantFP * /*FPImm*/) {
+ return 0;
+}
+
+unsigned FastISel::FastEmit_rri(MVT, MVT,
+ unsigned,
+ unsigned /*Op0*/, bool /*Op0IsKill*/,
+ unsigned /*Op1*/, bool /*Op1IsKill*/,
+ uint64_t /*Imm*/) {
+ return 0;
+}
+
+/// 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 FastISel::FastEmit_ri_(MVT VT, unsigned Opcode,
+ unsigned Op0, bool Op0IsKill,
+ uint64_t Imm, MVT ImmType) {
+ // If this is a multiply by a power of two, emit this as a shift left.
+ if (Opcode == ISD::MUL && isPowerOf2_64(Imm)) {
+ Opcode = ISD::SHL;
+ Imm = Log2_64(Imm);
+ } else if (Opcode == ISD::UDIV && isPowerOf2_64(Imm)) {
+ // div x, 8 -> srl x, 3
+ Opcode = ISD::SRL;
+ Imm = Log2_64(Imm);
+ }
+
+ // Horrible hack (to be removed), check to make sure shift amounts are
+ // in-range.
+ if ((Opcode == ISD::SHL || Opcode == ISD::SRA || Opcode == ISD::SRL) &&
+ Imm >= VT.getSizeInBits())
+ return 0;
+
+ // First check if immediate type is legal. If not, we can't use the ri form.
+ unsigned ResultReg = FastEmit_ri(VT, VT, Opcode, Op0, Op0IsKill, Imm);
+ if (ResultReg != 0)
+ return ResultReg;
+ unsigned MaterialReg = FastEmit_i(ImmType, ImmType, ISD::Constant, Imm);
+ if (MaterialReg == 0) {
+ // This is a bit ugly/slow, but failing here means falling out of
+ // fast-isel, which would be very slow.
+ IntegerType *ITy = IntegerType::get(FuncInfo.Fn->getContext(),
+ VT.getSizeInBits());
+ MaterialReg = getRegForValue(ConstantInt::get(ITy, Imm));
+ }
+ return FastEmit_rr(VT, VT, Opcode,
+ Op0, Op0IsKill,
+ MaterialReg, /*Kill=*/true);
+}
+
+unsigned FastISel::createResultReg(const TargetRegisterClass* RC) {
+ return MRI.createVirtualRegister(RC);
+}
+
+unsigned FastISel::FastEmitInst_(unsigned MachineInstOpcode,
+ const TargetRegisterClass* RC) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
+
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg);
return ResultReg;
}
unsigned FastISel::FastEmitInst_r(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
- unsigned Op0) {
- MachineRegisterInfo &MRI = MF->getRegInfo();
- const TargetInstrDesc &II = TII->get(MachineInstOpcode);
- unsigned ResultReg = MRI.createVirtualRegister(RC);
+ unsigned Op0, bool Op0IsKill) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
- MachineInstr *MI = BuildMI(*MF, II, ResultReg);
- MI->addOperand(MachineOperand::CreateReg(Op0, false));
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+ .addReg(Op0, Op0IsKill * RegState::Kill);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(Op0, Op0IsKill * RegState::Kill);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
- MBB->push_back(MI);
return ResultReg;
}
unsigned FastISel::FastEmitInst_rr(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
- unsigned Op0, unsigned Op1) {
- MachineRegisterInfo &MRI = MF->getRegInfo();
- const TargetInstrDesc &II = TII->get(MachineInstOpcode);
- unsigned ResultReg = MRI.createVirtualRegister(RC);
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
- MachineInstr *MI = BuildMI(*MF, II, ResultReg);
- MI->addOperand(MachineOperand::CreateReg(Op0, false));
- MI->addOperand(MachineOperand::CreateReg(Op1, false));
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addReg(Op1, Op1IsKill * RegState::Kill);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addReg(Op1, Op1IsKill * RegState::Kill);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
+ return ResultReg;
+}
+
+unsigned FastISel::FastEmitInst_rrr(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill,
+ unsigned Op2, bool Op2IsKill) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
- MBB->push_back(MI);
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addReg(Op1, Op1IsKill * RegState::Kill)
+ .addReg(Op2, Op2IsKill * RegState::Kill);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addReg(Op1, Op1IsKill * RegState::Kill)
+ .addReg(Op2, Op2IsKill * RegState::Kill);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
+ return ResultReg;
+}
+
+unsigned FastISel::FastEmitInst_ri(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ unsigned Op0, bool Op0IsKill,
+ uint64_t Imm) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
+
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addImm(Imm);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addImm(Imm);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
+ return ResultReg;
+}
+
+unsigned FastISel::FastEmitInst_rii(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ unsigned Op0, bool Op0IsKill,
+ uint64_t Imm1, uint64_t Imm2) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
+
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addImm(Imm1)
+ .addImm(Imm2);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addImm(Imm1)
+ .addImm(Imm2);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
+ return ResultReg;
+}
+
+unsigned FastISel::FastEmitInst_rf(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ unsigned Op0, bool Op0IsKill,
+ const ConstantFP *FPImm) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
+
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addFPImm(FPImm);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addFPImm(FPImm);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
return ResultReg;
}
+
+unsigned FastISel::FastEmitInst_rri(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ unsigned Op0, bool Op0IsKill,
+ unsigned Op1, bool Op1IsKill,
+ uint64_t Imm) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
+
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addReg(Op1, Op1IsKill * RegState::Kill)
+ .addImm(Imm);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+ .addReg(Op0, Op0IsKill * RegState::Kill)
+ .addReg(Op1, Op1IsKill * RegState::Kill)
+ .addImm(Imm);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
+ return ResultReg;
+}
+
+unsigned FastISel::FastEmitInst_i(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ uint64_t Imm) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
+
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg).addImm(Imm);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II).addImm(Imm);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
+ return ResultReg;
+}
+
+unsigned FastISel::FastEmitInst_ii(unsigned MachineInstOpcode,
+ const TargetRegisterClass *RC,
+ uint64_t Imm1, uint64_t Imm2) {
+ unsigned ResultReg = createResultReg(RC);
+ const MCInstrDesc &II = TII.get(MachineInstOpcode);
+
+ if (II.getNumDefs() >= 1)
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+ .addImm(Imm1).addImm(Imm2);
+ else {
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II).addImm(Imm1).addImm(Imm2);
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+ ResultReg).addReg(II.ImplicitDefs[0]);
+ }
+ return ResultReg;
+}
+
+unsigned FastISel::FastEmitInst_extractsubreg(MVT RetVT,
+ unsigned Op0, bool Op0IsKill,
+ uint32_t Idx) {
+ unsigned ResultReg = createResultReg(TLI.getRegClassFor(RetVT));
+ assert(TargetRegisterInfo::isVirtualRegister(Op0) &&
+ "Cannot yet extract from physregs");
+ BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt,
+ DL, TII.get(TargetOpcode::COPY), ResultReg)
+ .addReg(Op0, getKillRegState(Op0IsKill), Idx);
+ return ResultReg;
+}
+
+/// FastEmitZExtFromI1 - Emit MachineInstrs to compute the value of Op
+/// with all but the least significant bit set to zero.
+unsigned FastISel::FastEmitZExtFromI1(MVT VT, unsigned Op0, bool Op0IsKill) {
+ return FastEmit_ri(VT, VT, ISD::AND, Op0, Op0IsKill, 1);
+}
+
+/// 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 FastISel::HandlePHINodesInSuccessorBlocks(const BasicBlock *LLVMBB) {
+ const TerminatorInst *TI = LLVMBB->getTerminator();
+
+ SmallPtrSet<MachineBasicBlock *, 4> SuccsHandled;
+ unsigned OrigNumPHINodesToUpdate = FuncInfo.PHINodesToUpdate.size();
+
+ // Check successor nodes' PHI nodes that expect a constant to be available
+ // from this block.
+ for (unsigned succ = 0, e = TI->getNumSuccessors(); succ != e; ++succ) {
+ const BasicBlock *SuccBB = TI->getSuccessor(succ);
+ if (!isa<PHINode>(SuccBB->begin())) continue;
+ MachineBasicBlock *SuccMBB = FuncInfo.MBBMap[SuccBB];
+
+ // If this terminator has multiple identical successors (common for
+ // switches), only handle each succ once.
+ if (!SuccsHandled.insert(SuccMBB)) continue;
+
+ MachineBasicBlock::iterator MBBI = SuccMBB->begin();
+
+ // At this point we know that there is a 1-1 correspondence between LLVM PHI
+ // nodes and Machine PHI nodes, but the incoming operands have not been
+ // emitted yet.
+ for (BasicBlock::const_iterator I = SuccBB->begin();
+ const PHINode *PN = dyn_cast<PHINode>(I); ++I) {
+
+ // Ignore dead phi's.
+ if (PN->use_empty()) continue;
+
+ // Only handle legal types. Two interesting things to note here. First,
+ // by bailing out early, we may leave behind some dead instructions,
+ // since SelectionDAG's HandlePHINodesInSuccessorBlocks will insert its
+ // own moves. Second, this check is necessary because FastISel doesn't
+ // use CreateRegs to create registers, so it always creates
+ // exactly one register for each non-void instruction.
+ EVT VT = TLI.getValueType(PN->getType(), /*AllowUnknown=*/true);
+ if (VT == MVT::Other || !TLI.isTypeLegal(VT)) {
+ // Handle integer promotions, though, because they're common and easy.
+ if (VT == MVT::i1 || VT == MVT::i8 || VT == MVT::i16)
+ VT = TLI.getTypeToTransformTo(LLVMBB->getContext(), VT);
+ else {
+ FuncInfo.PHINodesToUpdate.resize(OrigNumPHINodesToUpdate);
+ return false;
+ }
+ }
+
+ const Value *PHIOp = PN->getIncomingValueForBlock(LLVMBB);
+
+ // Set the DebugLoc for the copy. Prefer the location of the operand
+ // if there is one; use the location of the PHI otherwise.
+ DL = PN->getDebugLoc();
+ if (const Instruction *Inst = dyn_cast<Instruction>(PHIOp))
+ DL = Inst->getDebugLoc();
+
+ unsigned Reg = getRegForValue(PHIOp);
+ if (Reg == 0) {
+ FuncInfo.PHINodesToUpdate.resize(OrigNumPHINodesToUpdate);
+ return false;
+ }
+ FuncInfo.PHINodesToUpdate.push_back(std::make_pair(MBBI++, Reg));
+ DL = DebugLoc();
+ }
+ }
+
+ return true;
+}