llvm-6502/lib/Target/Sparc/SparcISelDAGToDAG.cpp
Dan Gohman eeb3a00b84 Change SelectCode's argument from SDValue to SDNode *, to make it more
clear what information these functions are actually using.

This is also a micro-optimization, as passing a SDNode * around is
simpler than passing a { SDNode *, int } by value or reference.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92564 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 01:24:18 +00:00

231 lines
7.8 KiB
C++

//===-- SparcISelDAGToDAG.cpp - A dag to dag inst selector for Sparc ------===//
//
// 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 SPARC target.
//
//===----------------------------------------------------------------------===//
#include "SparcISelLowering.h"
#include "SparcTargetMachine.h"
#include "llvm/Intrinsics.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
//===----------------------------------------------------------------------===//
// Instruction Selector Implementation
//===----------------------------------------------------------------------===//
//===--------------------------------------------------------------------===//
/// SparcDAGToDAGISel - SPARC specific code to select SPARC machine
/// instructions for SelectionDAG operations.
///
namespace {
class SparcDAGToDAGISel : public SelectionDAGISel {
/// Subtarget - Keep a pointer to the Sparc Subtarget around so that we can
/// make the right decision when generating code for different targets.
const SparcSubtarget &Subtarget;
SparcTargetMachine& TM;
MachineBasicBlock *CurBB;
public:
explicit SparcDAGToDAGISel(SparcTargetMachine &tm)
: SelectionDAGISel(tm),
Subtarget(tm.getSubtarget<SparcSubtarget>()),
TM(tm) {
}
SDNode *Select(SDNode *N);
// Complex Pattern Selectors.
bool SelectADDRrr(SDNode *Op, SDValue N, SDValue &R1, SDValue &R2);
bool SelectADDRri(SDNode *Op, SDValue N, SDValue &Base,
SDValue &Offset);
/// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
/// inline asm expressions.
virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op,
char ConstraintCode,
std::vector<SDValue> &OutOps);
/// InstructionSelect - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
virtual void InstructionSelect();
virtual const char *getPassName() const {
return "SPARC DAG->DAG Pattern Instruction Selection";
}
// Include the pieces autogenerated from the target description.
#include "SparcGenDAGISel.inc"
private:
SDNode* getGlobalBaseReg();
};
} // end anonymous namespace
/// InstructionSelect - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
void SparcDAGToDAGISel::InstructionSelect() {
CurBB = BB;
// Select target instructions for the DAG.
SelectRoot(*CurDAG);
CurDAG->RemoveDeadNodes();
}
SDNode* SparcDAGToDAGISel::getGlobalBaseReg() {
MachineFunction *MF = CurBB->getParent();
unsigned GlobalBaseReg = TM.getInstrInfo()->getGlobalBaseReg(MF);
return CurDAG->getRegister(GlobalBaseReg, TLI.getPointerTy()).getNode();
}
bool SparcDAGToDAGISel::SelectADDRri(SDNode *Op, SDValue Addr,
SDValue &Base, SDValue &Offset) {
if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Addr)) {
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
Offset = CurDAG->getTargetConstant(0, MVT::i32);
return true;
}
if (Addr.getOpcode() == ISD::TargetExternalSymbol ||
Addr.getOpcode() == ISD::TargetGlobalAddress)
return false; // direct calls.
if (Addr.getOpcode() == ISD::ADD) {
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1))) {
if (Predicate_simm13(CN)) {
if (FrameIndexSDNode *FIN =
dyn_cast<FrameIndexSDNode>(Addr.getOperand(0))) {
// Constant offset from frame ref.
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
} else {
Base = Addr.getOperand(0);
}
Offset = CurDAG->getTargetConstant(CN->getZExtValue(), MVT::i32);
return true;
}
}
if (Addr.getOperand(0).getOpcode() == SPISD::Lo) {
Base = Addr.getOperand(1);
Offset = Addr.getOperand(0).getOperand(0);
return true;
}
if (Addr.getOperand(1).getOpcode() == SPISD::Lo) {
Base = Addr.getOperand(0);
Offset = Addr.getOperand(1).getOperand(0);
return true;
}
}
Base = Addr;
Offset = CurDAG->getTargetConstant(0, MVT::i32);
return true;
}
bool SparcDAGToDAGISel::SelectADDRrr(SDNode *Op, SDValue Addr,
SDValue &R1, SDValue &R2) {
if (Addr.getOpcode() == ISD::FrameIndex) return false;
if (Addr.getOpcode() == ISD::TargetExternalSymbol ||
Addr.getOpcode() == ISD::TargetGlobalAddress)
return false; // direct calls.
if (Addr.getOpcode() == ISD::ADD) {
if (isa<ConstantSDNode>(Addr.getOperand(1)) &&
Predicate_simm13(Addr.getOperand(1).getNode()))
return false; // Let the reg+imm pattern catch this!
if (Addr.getOperand(0).getOpcode() == SPISD::Lo ||
Addr.getOperand(1).getOpcode() == SPISD::Lo)
return false; // Let the reg+imm pattern catch this!
R1 = Addr.getOperand(0);
R2 = Addr.getOperand(1);
return true;
}
R1 = Addr;
R2 = CurDAG->getRegister(SP::G0, MVT::i32);
return true;
}
SDNode *SparcDAGToDAGISel::Select(SDNode *N) {
DebugLoc dl = N->getDebugLoc();
if (N->isMachineOpcode())
return NULL; // Already selected.
switch (N->getOpcode()) {
default: break;
case SPISD::GLOBAL_BASE_REG:
return getGlobalBaseReg();
case ISD::SDIV:
case ISD::UDIV: {
// FIXME: should use a custom expander to expose the SRA to the dag.
SDValue DivLHS = N->getOperand(0);
SDValue DivRHS = N->getOperand(1);
// Set the Y register to the high-part.
SDValue TopPart;
if (N->getOpcode() == ISD::SDIV) {
TopPart = SDValue(CurDAG->getMachineNode(SP::SRAri, dl, MVT::i32, DivLHS,
CurDAG->getTargetConstant(31, MVT::i32)), 0);
} else {
TopPart = CurDAG->getRegister(SP::G0, MVT::i32);
}
TopPart = SDValue(CurDAG->getMachineNode(SP::WRYrr, dl, MVT::Flag, TopPart,
CurDAG->getRegister(SP::G0, MVT::i32)), 0);
// FIXME: Handle div by immediate.
unsigned Opcode = N->getOpcode() == ISD::SDIV ? SP::SDIVrr : SP::UDIVrr;
return CurDAG->SelectNodeTo(N, Opcode, MVT::i32, DivLHS, DivRHS,
TopPart);
}
case ISD::MULHU:
case ISD::MULHS: {
// FIXME: Handle mul by immediate.
SDValue MulLHS = N->getOperand(0);
SDValue MulRHS = N->getOperand(1);
unsigned Opcode = N->getOpcode() == ISD::MULHU ? SP::UMULrr : SP::SMULrr;
SDNode *Mul = CurDAG->getMachineNode(Opcode, dl, MVT::i32, MVT::Flag,
MulLHS, MulRHS);
// The high part is in the Y register.
return CurDAG->SelectNodeTo(N, SP::RDY, MVT::i32, SDValue(Mul, 1));
return NULL;
}
}
return SelectCode(N);
}
/// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
/// inline asm expressions.
bool
SparcDAGToDAGISel::SelectInlineAsmMemoryOperand(const SDValue &Op,
char ConstraintCode,
std::vector<SDValue> &OutOps) {
SDValue Op0, Op1;
switch (ConstraintCode) {
default: return true;
case 'm': // memory
if (!SelectADDRrr(Op.getNode(), Op, Op0, Op1))
SelectADDRri(Op.getNode(), Op, Op0, Op1);
break;
}
OutOps.push_back(Op0);
OutOps.push_back(Op1);
return false;
}
/// createSparcISelDag - This pass converts a legalized DAG into a
/// SPARC-specific DAG, ready for instruction scheduling.
///
FunctionPass *llvm::createSparcISelDag(SparcTargetMachine &TM) {
return new SparcDAGToDAGISel(TM);
}