diff options
Diffstat (limited to 'contrib/llvm/lib/Target/Alpha/AlphaISelDAGToDAG.cpp')
-rw-r--r-- | contrib/llvm/lib/Target/Alpha/AlphaISelDAGToDAG.cpp | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/Alpha/AlphaISelDAGToDAG.cpp b/contrib/llvm/lib/Target/Alpha/AlphaISelDAGToDAG.cpp new file mode 100644 index 0000000..d526dc0 --- /dev/null +++ b/contrib/llvm/lib/Target/Alpha/AlphaISelDAGToDAG.cpp @@ -0,0 +1,439 @@ +//===-- AlphaISelDAGToDAG.cpp - Alpha pattern matching inst selector ------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file defines a pattern matching instruction selector for Alpha, +// converting from a legalized dag to a Alpha dag. +// +//===----------------------------------------------------------------------===// + +#include "Alpha.h" +#include "AlphaTargetMachine.h" +#include "llvm/CodeGen/MachineInstrBuilder.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/CodeGen/SelectionDAG.h" +#include "llvm/CodeGen/SelectionDAGISel.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Constants.h" +#include "llvm/DerivedTypes.h" +#include "llvm/GlobalValue.h" +#include "llvm/Intrinsics.h" +#include "llvm/LLVMContext.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/MathExtras.h" +#include "llvm/Support/raw_ostream.h" +#include <algorithm> +using namespace llvm; + +namespace { + + //===--------------------------------------------------------------------===// + /// AlphaDAGToDAGISel - Alpha specific code to select Alpha machine + /// instructions for SelectionDAG operations. + class AlphaDAGToDAGISel : public SelectionDAGISel { + static const int64_t IMM_LOW = -32768; + static const int64_t IMM_HIGH = 32767; + static const int64_t IMM_MULT = 65536; + static const int64_t IMM_FULLHIGH = IMM_HIGH + IMM_HIGH * IMM_MULT; + static const int64_t IMM_FULLLOW = IMM_LOW + IMM_LOW * IMM_MULT; + + static int64_t get_ldah16(int64_t x) { + int64_t y = x / IMM_MULT; + if (x % IMM_MULT > IMM_HIGH) + ++y; + return y; + } + + static int64_t get_lda16(int64_t x) { + return x - get_ldah16(x) * IMM_MULT; + } + + /// get_zapImm - Return a zap mask if X is a valid immediate for a zapnot + /// instruction (if not, return 0). Note that this code accepts partial + /// zap masks. For example (and LHS, 1) is a valid zap, as long we know + /// that the bits 1-7 of LHS are already zero. If LHS is non-null, we are + /// in checking mode. If LHS is null, we assume that the mask has already + /// been validated before. + uint64_t get_zapImm(SDValue LHS, uint64_t Constant) const { + uint64_t BitsToCheck = 0; + unsigned Result = 0; + for (unsigned i = 0; i != 8; ++i) { + if (((Constant >> 8*i) & 0xFF) == 0) { + // nothing to do. + } else { + Result |= 1 << i; + if (((Constant >> 8*i) & 0xFF) == 0xFF) { + // If the entire byte is set, zapnot the byte. + } else if (LHS.getNode() == 0) { + // Otherwise, if the mask was previously validated, we know its okay + // to zapnot this entire byte even though all the bits aren't set. + } else { + // Otherwise we don't know that the it's okay to zapnot this entire + // byte. Only do this iff we can prove that the missing bits are + // already null, so the bytezap doesn't need to really null them. + BitsToCheck |= ~Constant & (0xFF << 8*i); + } + } + } + + // If there are missing bits in a byte (for example, X & 0xEF00), check to + // see if the missing bits (0x1000) are already known zero if not, the zap + // isn't okay to do, as it won't clear all the required bits. + if (BitsToCheck && + !CurDAG->MaskedValueIsZero(LHS, + APInt(LHS.getValueSizeInBits(), + BitsToCheck))) + return 0; + + return Result; + } + + static uint64_t get_zapImm(uint64_t x) { + unsigned build = 0; + for(int i = 0; i != 8; ++i) { + if ((x & 0x00FF) == 0x00FF) + build |= 1 << i; + else if ((x & 0x00FF) != 0) + return 0; + x >>= 8; + } + return build; + } + + + static uint64_t getNearPower2(uint64_t x) { + if (!x) return 0; + unsigned at = CountLeadingZeros_64(x); + uint64_t complow = 1 << (63 - at); + uint64_t comphigh = 1 << (64 - at); + //cerr << x << ":" << complow << ":" << comphigh << "\n"; + if (abs64(complow - x) <= abs64(comphigh - x)) + return complow; + else + return comphigh; + } + + static bool chkRemNearPower2(uint64_t x, uint64_t r, bool swap) { + uint64_t y = getNearPower2(x); + if (swap) + return (y - x) == r; + else + return (x - y) == r; + } + + static bool isFPZ(SDValue N) { + ConstantFPSDNode *CN = dyn_cast<ConstantFPSDNode>(N); + return (CN && (CN->getValueAPF().isZero())); + } + static bool isFPZn(SDValue N) { + ConstantFPSDNode *CN = dyn_cast<ConstantFPSDNode>(N); + return (CN && CN->getValueAPF().isNegZero()); + } + static bool isFPZp(SDValue N) { + ConstantFPSDNode *CN = dyn_cast<ConstantFPSDNode>(N); + return (CN && CN->getValueAPF().isPosZero()); + } + + public: + explicit AlphaDAGToDAGISel(AlphaTargetMachine &TM) + : SelectionDAGISel(TM) + {} + + /// getI64Imm - Return a target constant with the specified value, of type + /// i64. + inline SDValue getI64Imm(int64_t Imm) { + return CurDAG->getTargetConstant(Imm, MVT::i64); + } + + // Select - Convert the specified operand from a target-independent to a + // target-specific node if it hasn't already been changed. + SDNode *Select(SDNode *N); + + virtual const char *getPassName() const { + return "Alpha DAG->DAG Pattern Instruction Selection"; + } + + /// SelectInlineAsmMemoryOperand - Implement addressing mode selection for + /// inline asm expressions. + virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op, + char ConstraintCode, + std::vector<SDValue> &OutOps) { + SDValue Op0; + switch (ConstraintCode) { + default: return true; + case 'm': // memory + Op0 = Op; + break; + } + + OutOps.push_back(Op0); + return false; + } + +// Include the pieces autogenerated from the target description. +#include "AlphaGenDAGISel.inc" + +private: + /// getTargetMachine - Return a reference to the TargetMachine, casted + /// to the target-specific type. + const AlphaTargetMachine &getTargetMachine() { + return static_cast<const AlphaTargetMachine &>(TM); + } + + /// getInstrInfo - Return a reference to the TargetInstrInfo, casted + /// to the target-specific type. + const AlphaInstrInfo *getInstrInfo() { + return getTargetMachine().getInstrInfo(); + } + + SDNode *getGlobalBaseReg(); + SDNode *getGlobalRetAddr(); + void SelectCALL(SDNode *Op); + + }; +} + +/// getGlobalBaseReg - Output the instructions required to put the +/// GOT address into a register. +/// +SDNode *AlphaDAGToDAGISel::getGlobalBaseReg() { + unsigned GlobalBaseReg = getInstrInfo()->getGlobalBaseReg(MF); + return CurDAG->getRegister(GlobalBaseReg, TLI.getPointerTy()).getNode(); +} + +/// getGlobalRetAddr - Grab the return address. +/// +SDNode *AlphaDAGToDAGISel::getGlobalRetAddr() { + unsigned GlobalRetAddr = getInstrInfo()->getGlobalRetAddr(MF); + return CurDAG->getRegister(GlobalRetAddr, TLI.getPointerTy()).getNode(); +} + +// Select - Convert the specified operand from a target-independent to a +// target-specific node if it hasn't already been changed. +SDNode *AlphaDAGToDAGISel::Select(SDNode *N) { + if (N->isMachineOpcode()) + return NULL; // Already selected. + DebugLoc dl = N->getDebugLoc(); + + switch (N->getOpcode()) { + default: break; + case AlphaISD::CALL: + SelectCALL(N); + return NULL; + + case ISD::FrameIndex: { + int FI = cast<FrameIndexSDNode>(N)->getIndex(); + return CurDAG->SelectNodeTo(N, Alpha::LDA, MVT::i64, + CurDAG->getTargetFrameIndex(FI, MVT::i32), + getI64Imm(0)); + } + case ISD::GLOBAL_OFFSET_TABLE: + return getGlobalBaseReg(); + case AlphaISD::GlobalRetAddr: + return getGlobalRetAddr(); + + case AlphaISD::DivCall: { + SDValue Chain = CurDAG->getEntryNode(); + SDValue N0 = N->getOperand(0); + SDValue N1 = N->getOperand(1); + SDValue N2 = N->getOperand(2); + Chain = CurDAG->getCopyToReg(Chain, dl, Alpha::R24, N1, + SDValue(0,0)); + Chain = CurDAG->getCopyToReg(Chain, dl, Alpha::R25, N2, + Chain.getValue(1)); + Chain = CurDAG->getCopyToReg(Chain, dl, Alpha::R27, N0, + Chain.getValue(1)); + SDNode *CNode = + CurDAG->getMachineNode(Alpha::JSRs, dl, MVT::Other, MVT::Flag, + Chain, Chain.getValue(1)); + Chain = CurDAG->getCopyFromReg(Chain, dl, Alpha::R27, MVT::i64, + SDValue(CNode, 1)); + return CurDAG->SelectNodeTo(N, Alpha::BISr, MVT::i64, Chain, Chain); + } + + case ISD::READCYCLECOUNTER: { + SDValue Chain = N->getOperand(0); + return CurDAG->getMachineNode(Alpha::RPCC, dl, MVT::i64, MVT::Other, + Chain); + } + + case ISD::Constant: { + uint64_t uval = cast<ConstantSDNode>(N)->getZExtValue(); + + if (uval == 0) { + SDValue Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), dl, + Alpha::R31, MVT::i64); + ReplaceUses(SDValue(N, 0), Result); + return NULL; + } + + int64_t val = (int64_t)uval; + int32_t val32 = (int32_t)val; + if (val <= IMM_HIGH + IMM_HIGH * IMM_MULT && + val >= IMM_LOW + IMM_LOW * IMM_MULT) + break; //(LDAH (LDA)) + if ((uval >> 32) == 0 && //empty upper bits + val32 <= IMM_HIGH + IMM_HIGH * IMM_MULT) + // val32 >= IMM_LOW + IMM_LOW * IMM_MULT) //always true + break; //(zext (LDAH (LDA))) + //Else use the constant pool + ConstantInt *C = ConstantInt::get( + Type::getInt64Ty(*CurDAG->getContext()), uval); + SDValue CPI = CurDAG->getTargetConstantPool(C, MVT::i64); + SDNode *Tmp = CurDAG->getMachineNode(Alpha::LDAHr, dl, MVT::i64, CPI, + SDValue(getGlobalBaseReg(), 0)); + return CurDAG->SelectNodeTo(N, Alpha::LDQr, MVT::i64, MVT::Other, + CPI, SDValue(Tmp, 0), CurDAG->getEntryNode()); + } + case ISD::TargetConstantFP: + case ISD::ConstantFP: { + ConstantFPSDNode *CN = cast<ConstantFPSDNode>(N); + bool isDouble = N->getValueType(0) == MVT::f64; + EVT T = isDouble ? MVT::f64 : MVT::f32; + if (CN->getValueAPF().isPosZero()) { + return CurDAG->SelectNodeTo(N, isDouble ? Alpha::CPYST : Alpha::CPYSS, + T, CurDAG->getRegister(Alpha::F31, T), + CurDAG->getRegister(Alpha::F31, T)); + } else if (CN->getValueAPF().isNegZero()) { + return CurDAG->SelectNodeTo(N, isDouble ? Alpha::CPYSNT : Alpha::CPYSNS, + T, CurDAG->getRegister(Alpha::F31, T), + CurDAG->getRegister(Alpha::F31, T)); + } else { + report_fatal_error("Unhandled FP constant type"); + } + break; + } + + case ISD::SETCC: + if (N->getOperand(0).getNode()->getValueType(0).isFloatingPoint()) { + ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(2))->get(); + + unsigned Opc = Alpha::WTF; + bool rev = false; + bool inv = false; + switch(CC) { + default: DEBUG(N->dump(CurDAG)); llvm_unreachable("Unknown FP comparison!"); + case ISD::SETEQ: case ISD::SETOEQ: case ISD::SETUEQ: + Opc = Alpha::CMPTEQ; break; + case ISD::SETLT: case ISD::SETOLT: case ISD::SETULT: + Opc = Alpha::CMPTLT; break; + case ISD::SETLE: case ISD::SETOLE: case ISD::SETULE: + Opc = Alpha::CMPTLE; break; + case ISD::SETGT: case ISD::SETOGT: case ISD::SETUGT: + Opc = Alpha::CMPTLT; rev = true; break; + case ISD::SETGE: case ISD::SETOGE: case ISD::SETUGE: + Opc = Alpha::CMPTLE; rev = true; break; + case ISD::SETNE: case ISD::SETONE: case ISD::SETUNE: + Opc = Alpha::CMPTEQ; inv = true; break; + case ISD::SETO: + Opc = Alpha::CMPTUN; inv = true; break; + case ISD::SETUO: + Opc = Alpha::CMPTUN; break; + }; + SDValue tmp1 = N->getOperand(rev?1:0); + SDValue tmp2 = N->getOperand(rev?0:1); + SDNode *cmp = CurDAG->getMachineNode(Opc, dl, MVT::f64, tmp1, tmp2); + if (inv) + cmp = CurDAG->getMachineNode(Alpha::CMPTEQ, dl, + MVT::f64, SDValue(cmp, 0), + CurDAG->getRegister(Alpha::F31, MVT::f64)); + switch(CC) { + case ISD::SETUEQ: case ISD::SETULT: case ISD::SETULE: + case ISD::SETUNE: case ISD::SETUGT: case ISD::SETUGE: + { + SDNode* cmp2 = CurDAG->getMachineNode(Alpha::CMPTUN, dl, MVT::f64, + tmp1, tmp2); + cmp = CurDAG->getMachineNode(Alpha::ADDT, dl, MVT::f64, + SDValue(cmp2, 0), SDValue(cmp, 0)); + break; + } + default: break; + } + + SDNode* LD = CurDAG->getMachineNode(Alpha::FTOIT, dl, + MVT::i64, SDValue(cmp, 0)); + return CurDAG->getMachineNode(Alpha::CMPULT, dl, MVT::i64, + CurDAG->getRegister(Alpha::R31, MVT::i64), + SDValue(LD,0)); + } + break; + + case ISD::AND: { + ConstantSDNode* SC = NULL; + ConstantSDNode* MC = NULL; + if (N->getOperand(0).getOpcode() == ISD::SRL && + (MC = dyn_cast<ConstantSDNode>(N->getOperand(1))) && + (SC = dyn_cast<ConstantSDNode>(N->getOperand(0).getOperand(1)))) { + uint64_t sval = SC->getZExtValue(); + uint64_t mval = MC->getZExtValue(); + // If the result is a zap, let the autogened stuff handle it. + if (get_zapImm(N->getOperand(0), mval)) + break; + // given mask X, and shift S, we want to see if there is any zap in the + // mask if we play around with the botton S bits + uint64_t dontcare = (~0ULL) >> (64 - sval); + uint64_t mask = mval << sval; + + if (get_zapImm(mask | dontcare)) + mask = mask | dontcare; + + if (get_zapImm(mask)) { + SDValue Z = + SDValue(CurDAG->getMachineNode(Alpha::ZAPNOTi, dl, MVT::i64, + N->getOperand(0).getOperand(0), + getI64Imm(get_zapImm(mask))), 0); + return CurDAG->getMachineNode(Alpha::SRLr, dl, MVT::i64, Z, + getI64Imm(sval)); + } + } + break; + } + + } + + return SelectCode(N); +} + +void AlphaDAGToDAGISel::SelectCALL(SDNode *N) { + //TODO: add flag stuff to prevent nondeturministic breakage! + + SDValue Chain = N->getOperand(0); + SDValue Addr = N->getOperand(1); + SDValue InFlag = N->getOperand(N->getNumOperands() - 1); + DebugLoc dl = N->getDebugLoc(); + + if (Addr.getOpcode() == AlphaISD::GPRelLo) { + SDValue GOT = SDValue(getGlobalBaseReg(), 0); + Chain = CurDAG->getCopyToReg(Chain, dl, Alpha::R29, GOT, InFlag); + InFlag = Chain.getValue(1); + Chain = SDValue(CurDAG->getMachineNode(Alpha::BSR, dl, MVT::Other, + MVT::Flag, Addr.getOperand(0), + Chain, InFlag), 0); + } else { + Chain = CurDAG->getCopyToReg(Chain, dl, Alpha::R27, Addr, InFlag); + InFlag = Chain.getValue(1); + Chain = SDValue(CurDAG->getMachineNode(Alpha::JSR, dl, MVT::Other, + MVT::Flag, Chain, InFlag), 0); + } + InFlag = Chain.getValue(1); + + ReplaceUses(SDValue(N, 0), Chain); + ReplaceUses(SDValue(N, 1), InFlag); +} + + +/// createAlphaISelDag - This pass converts a legalized DAG into a +/// Alpha-specific DAG, ready for instruction scheduling. +/// +FunctionPass *llvm::createAlphaISelDag(AlphaTargetMachine &TM) { + return new AlphaDAGToDAGISel(TM); +} |