mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-29 13:29:28 +00:00
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52923 91177308-0d34-0410-b5e6-96231b3b80d8
410 lines
12 KiB
C++
410 lines
12 KiB
C++
//===-- MipsISelDAGToDAG.cpp - A dag to dag inst selector for Mips --------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file defines an instruction selector for the MIPS target.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#define DEBUG_TYPE "mips-isel"
|
|
#include "Mips.h"
|
|
#include "MipsISelLowering.h"
|
|
#include "MipsMachineFunction.h"
|
|
#include "MipsRegisterInfo.h"
|
|
#include "MipsSubtarget.h"
|
|
#include "MipsTargetMachine.h"
|
|
#include "llvm/GlobalValue.h"
|
|
#include "llvm/Instructions.h"
|
|
#include "llvm/Intrinsics.h"
|
|
#include "llvm/Support/CFG.h"
|
|
#include "llvm/Type.h"
|
|
#include "llvm/CodeGen/MachineConstantPool.h"
|
|
#include "llvm/CodeGen/MachineFunction.h"
|
|
#include "llvm/CodeGen/MachineFrameInfo.h"
|
|
#include "llvm/CodeGen/MachineInstrBuilder.h"
|
|
#include "llvm/CodeGen/MachineRegisterInfo.h"
|
|
#include "llvm/CodeGen/SelectionDAGISel.h"
|
|
#include "llvm/Target/TargetMachine.h"
|
|
#include "llvm/Support/Compiler.h"
|
|
#include "llvm/Support/Debug.h"
|
|
#include <queue>
|
|
#include <set>
|
|
|
|
using namespace llvm;
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Instruction Selector Implementation
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// MipsDAGToDAGISel - MIPS specific code to select MIPS machine
|
|
// instructions for SelectionDAG operations.
|
|
//===----------------------------------------------------------------------===//
|
|
namespace {
|
|
|
|
class VISIBILITY_HIDDEN MipsDAGToDAGISel : public SelectionDAGISel {
|
|
|
|
/// TM - Keep a reference to MipsTargetMachine.
|
|
MipsTargetMachine &TM;
|
|
|
|
/// MipsLowering - This object fully describes how to lower LLVM code to an
|
|
/// Mips-specific SelectionDAG.
|
|
MipsTargetLowering MipsLowering;
|
|
|
|
/// Subtarget - Keep a pointer to the MipsSubtarget around so that we can
|
|
/// make the right decision when generating code for different targets.
|
|
//TODO: add initialization on constructor
|
|
//const MipsSubtarget *Subtarget;
|
|
|
|
public:
|
|
MipsDAGToDAGISel(MipsTargetMachine &tm) :
|
|
SelectionDAGISel(MipsLowering),
|
|
TM(tm), MipsLowering(*TM.getTargetLowering()) {}
|
|
|
|
virtual void InstructionSelect(SelectionDAG &SD);
|
|
|
|
// Pass Name
|
|
virtual const char *getPassName() const {
|
|
return "MIPS DAG->DAG Pattern Instruction Selection";
|
|
}
|
|
|
|
|
|
private:
|
|
// Include the pieces autogenerated from the target description.
|
|
#include "MipsGenDAGISel.inc"
|
|
|
|
SDOperand getGlobalBaseReg();
|
|
SDNode *Select(SDOperand N);
|
|
|
|
// Complex Pattern.
|
|
bool SelectAddr(SDOperand Op, SDOperand N,
|
|
SDOperand &Base, SDOperand &Offset);
|
|
|
|
|
|
// getI32Imm - Return a target constant with the specified
|
|
// value, of type i32.
|
|
inline SDOperand getI32Imm(unsigned Imm) {
|
|
return CurDAG->getTargetConstant(Imm, MVT::i32);
|
|
}
|
|
|
|
|
|
#ifndef NDEBUG
|
|
unsigned Indent;
|
|
#endif
|
|
};
|
|
|
|
}
|
|
|
|
/// InstructionSelect - This callback is invoked by
|
|
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
|
|
void MipsDAGToDAGISel::
|
|
InstructionSelect(SelectionDAG &SD)
|
|
{
|
|
DEBUG(BB->dump());
|
|
// Codegen the basic block.
|
|
#ifndef NDEBUG
|
|
DOUT << "===== Instruction selection begins:\n";
|
|
Indent = 0;
|
|
#endif
|
|
|
|
// Select target instructions for the DAG.
|
|
SD.setRoot(SelectRoot(SD.getRoot()));
|
|
|
|
#ifndef NDEBUG
|
|
DOUT << "===== Instruction selection ends:\n";
|
|
#endif
|
|
|
|
SD.RemoveDeadNodes();
|
|
}
|
|
|
|
/// getGlobalBaseReg - Output the instructions required to put the
|
|
/// GOT address into a register.
|
|
SDOperand MipsDAGToDAGISel::getGlobalBaseReg() {
|
|
MachineFunction* MF = BB->getParent();
|
|
unsigned GP = 0;
|
|
for(MachineRegisterInfo::livein_iterator ii = MF->getRegInfo().livein_begin(),
|
|
ee = MF->getRegInfo().livein_end(); ii != ee; ++ii)
|
|
if (ii->first == Mips::GP) {
|
|
GP = ii->second;
|
|
break;
|
|
}
|
|
assert(GP && "GOT PTR not in liveins");
|
|
return CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
|
|
GP, MVT::i32);
|
|
}
|
|
|
|
/// ComplexPattern used on MipsInstrInfo
|
|
/// Used on Mips Load/Store instructions
|
|
bool MipsDAGToDAGISel::
|
|
SelectAddr(SDOperand Op, SDOperand Addr, SDOperand &Offset, SDOperand &Base)
|
|
{
|
|
// if Address is FI, get the TargetFrameIndex.
|
|
if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Addr)) {
|
|
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
|
|
Offset = CurDAG->getTargetConstant(0, MVT::i32);
|
|
return true;
|
|
}
|
|
|
|
// on PIC code Load GA
|
|
if (TM.getRelocationModel() == Reloc::PIC_) {
|
|
if ((Addr.getOpcode() == ISD::TargetGlobalAddress) ||
|
|
(Addr.getOpcode() == ISD::TargetJumpTable)){
|
|
Base = CurDAG->getRegister(Mips::GP, MVT::i32);
|
|
Offset = Addr;
|
|
return true;
|
|
}
|
|
} else {
|
|
if ((Addr.getOpcode() == ISD::TargetExternalSymbol ||
|
|
Addr.getOpcode() == ISD::TargetGlobalAddress))
|
|
return false;
|
|
}
|
|
|
|
// Operand is a result from an ADD.
|
|
if (Addr.getOpcode() == ISD::ADD) {
|
|
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1))) {
|
|
if (Predicate_immSExt16(CN)) {
|
|
|
|
// If the first operand is a FI, get the TargetFI Node
|
|
if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>
|
|
(Addr.getOperand(0))) {
|
|
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
|
|
} else {
|
|
Base = Addr.getOperand(0);
|
|
}
|
|
|
|
Offset = CurDAG->getTargetConstant(CN->getValue(), MVT::i32);
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
Base = Addr;
|
|
Offset = CurDAG->getTargetConstant(0, MVT::i32);
|
|
return true;
|
|
}
|
|
|
|
/// Select instructions not customized! Used for
|
|
/// expanded, promoted and normal instructions
|
|
SDNode* MipsDAGToDAGISel::
|
|
Select(SDOperand N)
|
|
{
|
|
SDNode *Node = N.Val;
|
|
unsigned Opcode = Node->getOpcode();
|
|
|
|
// Dump information about the Node being selected
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent, ' ') << "Selecting: ";
|
|
DEBUG(Node->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent += 2;
|
|
#endif
|
|
|
|
// If we have a custom node, we already have selected!
|
|
if (Opcode >= ISD::BUILTIN_OP_END && Opcode < MipsISD::FIRST_NUMBER) {
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "== ";
|
|
DEBUG(Node->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent -= 2;
|
|
#endif
|
|
return NULL;
|
|
}
|
|
|
|
///
|
|
// Instruction Selection not handled by the auto-generated
|
|
// tablegen selection should be handled here.
|
|
///
|
|
switch(Opcode) {
|
|
|
|
default: break;
|
|
|
|
case ISD::SUBE:
|
|
case ISD::ADDE: {
|
|
SDOperand InFlag = Node->getOperand(2), CmpLHS;
|
|
unsigned Opc = InFlag.getOpcode(), MOp;
|
|
|
|
assert(((Opc == ISD::ADDC || Opc == ISD::ADDE) ||
|
|
(Opc == ISD::SUBC || Opc == ISD::SUBE)) &&
|
|
"(ADD|SUB)E flag operand must come from (ADD|SUB)C/E insn");
|
|
|
|
if (Opcode == ISD::ADDE) {
|
|
CmpLHS = InFlag.getValue(0);
|
|
MOp = Mips::ADDu;
|
|
} else {
|
|
CmpLHS = InFlag.getOperand(0);
|
|
MOp = Mips::SUBu;
|
|
}
|
|
|
|
SDOperand Ops[] = { CmpLHS, InFlag.getOperand(1) };
|
|
|
|
SDOperand LHS = Node->getOperand(0);
|
|
SDOperand RHS = Node->getOperand(1);
|
|
AddToISelQueue(LHS);
|
|
AddToISelQueue(RHS);
|
|
|
|
MVT VT = LHS.getValueType();
|
|
SDNode *Carry = CurDAG->getTargetNode(Mips::SLTu, VT, Ops, 2);
|
|
SDNode *AddCarry = CurDAG->getTargetNode(Mips::ADDu, VT,
|
|
SDOperand(Carry,0), RHS);
|
|
|
|
return CurDAG->SelectNodeTo(N.Val, MOp, VT, MVT::Flag,
|
|
LHS, SDOperand(AddCarry,0));
|
|
}
|
|
|
|
/// Mul/Div with two results
|
|
case ISD::SDIVREM:
|
|
case ISD::UDIVREM:
|
|
case ISD::SMUL_LOHI:
|
|
case ISD::UMUL_LOHI: {
|
|
SDOperand Op1 = Node->getOperand(0);
|
|
SDOperand Op2 = Node->getOperand(1);
|
|
AddToISelQueue(Op1);
|
|
AddToISelQueue(Op2);
|
|
|
|
unsigned Op;
|
|
if (Opcode == ISD::UMUL_LOHI || Opcode == ISD::SMUL_LOHI)
|
|
Op = (Opcode == ISD::UMUL_LOHI ? Mips::MULTu : Mips::MULT);
|
|
else
|
|
Op = (Opcode == ISD::UDIVREM ? Mips::DIVu : Mips::DIV);
|
|
|
|
SDNode *Node = CurDAG->getTargetNode(Op, MVT::Flag, Op1, Op2);
|
|
|
|
SDOperand InFlag = SDOperand(Node, 0);
|
|
SDNode *Lo = CurDAG->getTargetNode(Mips::MFLO, MVT::i32, MVT::Flag, InFlag);
|
|
|
|
InFlag = SDOperand(Lo,1);
|
|
SDNode *Hi = CurDAG->getTargetNode(Mips::MFHI, MVT::i32, InFlag);
|
|
|
|
if (!N.getValue(0).use_empty())
|
|
ReplaceUses(N.getValue(0), SDOperand(Lo,0));
|
|
|
|
if (!N.getValue(1).use_empty())
|
|
ReplaceUses(N.getValue(1), SDOperand(Hi,0));
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/// Special Muls
|
|
case ISD::MUL:
|
|
case ISD::MULHS:
|
|
case ISD::MULHU: {
|
|
SDOperand MulOp1 = Node->getOperand(0);
|
|
SDOperand MulOp2 = Node->getOperand(1);
|
|
AddToISelQueue(MulOp1);
|
|
AddToISelQueue(MulOp2);
|
|
|
|
unsigned MulOp = (Opcode == ISD::MULHU ? Mips::MULTu : Mips::MULT);
|
|
SDNode *MulNode = CurDAG->getTargetNode(MulOp, MVT::Flag, MulOp1, MulOp2);
|
|
|
|
SDOperand InFlag = SDOperand(MulNode, 0);
|
|
|
|
if (MulOp == ISD::MUL)
|
|
return CurDAG->getTargetNode(Mips::MFLO, MVT::i32, InFlag);
|
|
else
|
|
return CurDAG->getTargetNode(Mips::MFHI, MVT::i32, InFlag);
|
|
}
|
|
|
|
/// Div/Rem operations
|
|
case ISD::SREM:
|
|
case ISD::UREM:
|
|
case ISD::SDIV:
|
|
case ISD::UDIV: {
|
|
SDOperand Op1 = Node->getOperand(0);
|
|
SDOperand Op2 = Node->getOperand(1);
|
|
AddToISelQueue(Op1);
|
|
AddToISelQueue(Op2);
|
|
|
|
unsigned Op, MOp;
|
|
if (Opcode == ISD::SDIV || Opcode == ISD::UDIV) {
|
|
Op = (Opcode == ISD::SDIV ? Mips::DIV : Mips::DIVu);
|
|
MOp = Mips::MFLO;
|
|
} else {
|
|
Op = (Opcode == ISD::SREM ? Mips::DIV : Mips::DIVu);
|
|
MOp = Mips::MFHI;
|
|
}
|
|
SDNode *Node = CurDAG->getTargetNode(Op, MVT::Flag, Op1, Op2);
|
|
|
|
SDOperand InFlag = SDOperand(Node, 0);
|
|
return CurDAG->getTargetNode(MOp, MVT::i32, InFlag);
|
|
}
|
|
|
|
// Get target GOT address.
|
|
case ISD::GLOBAL_OFFSET_TABLE: {
|
|
SDOperand Result = getGlobalBaseReg();
|
|
ReplaceUses(N, Result);
|
|
return NULL;
|
|
}
|
|
|
|
/// Handle direct and indirect calls when using PIC. On PIC, when
|
|
/// GOT is smaller than about 64k (small code) the GA target is
|
|
/// loaded with only one instruction. Otherwise GA's target must
|
|
/// be loaded with 3 instructions.
|
|
case MipsISD::JmpLink: {
|
|
if (TM.getRelocationModel() == Reloc::PIC_) {
|
|
//bool isCodeLarge = (TM.getCodeModel() == CodeModel::Large);
|
|
SDOperand Chain = Node->getOperand(0);
|
|
SDOperand Callee = Node->getOperand(1);
|
|
AddToISelQueue(Chain);
|
|
SDOperand T9Reg = CurDAG->getRegister(Mips::T9, MVT::i32);
|
|
SDOperand InFlag(0, 0);
|
|
|
|
if ( (isa<GlobalAddressSDNode>(Callee)) ||
|
|
(isa<ExternalSymbolSDNode>(Callee)) )
|
|
{
|
|
/// Direct call for global addresses and external symbols
|
|
SDOperand GPReg = CurDAG->getRegister(Mips::GP, MVT::i32);
|
|
|
|
// Use load to get GOT target
|
|
SDOperand Ops[] = { Callee, GPReg, Chain };
|
|
SDOperand Load = SDOperand(CurDAG->getTargetNode(Mips::LW, MVT::i32,
|
|
MVT::Other, Ops, 3), 0);
|
|
Chain = Load.getValue(1);
|
|
AddToISelQueue(Chain);
|
|
|
|
// Call target must be on T9
|
|
Chain = CurDAG->getCopyToReg(Chain, T9Reg, Load, InFlag);
|
|
} else
|
|
/// Indirect call
|
|
Chain = CurDAG->getCopyToReg(Chain, T9Reg, Callee, InFlag);
|
|
|
|
AddToISelQueue(Chain);
|
|
|
|
// Emit Jump and Link Register
|
|
SDNode *ResNode = CurDAG->getTargetNode(Mips::JALR, MVT::Other,
|
|
MVT::Flag, T9Reg, Chain);
|
|
Chain = SDOperand(ResNode, 0);
|
|
InFlag = SDOperand(ResNode, 1);
|
|
ReplaceUses(SDOperand(Node, 0), Chain);
|
|
ReplaceUses(SDOperand(Node, 1), InFlag);
|
|
return ResNode;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Select the default instruction
|
|
SDNode *ResNode = SelectCode(N);
|
|
|
|
#ifndef NDEBUG
|
|
DOUT << std::string(Indent-2, ' ') << "=> ";
|
|
if (ResNode == NULL || ResNode == N.Val)
|
|
DEBUG(N.Val->dump(CurDAG));
|
|
else
|
|
DEBUG(ResNode->dump(CurDAG));
|
|
DOUT << "\n";
|
|
Indent -= 2;
|
|
#endif
|
|
|
|
return ResNode;
|
|
}
|
|
|
|
/// createMipsISelDag - This pass converts a legalized DAG into a
|
|
/// MIPS-specific DAG, ready for instruction scheduling.
|
|
FunctionPass *llvm::createMipsISelDag(MipsTargetMachine &TM) {
|
|
return new MipsDAGToDAGISel(TM);
|
|
}
|