llvm-6502/lib/Target/PTX/PTXISelDAGToDAG.cpp
Justin Holewinski a5ccb4e974 PTX: Prevent DCE from eliminating st.param calls, and unify the handling of
st.param and ld.param

FIXME: Test cases still need to be updated

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133733 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-23 18:10:05 +00:00

183 lines
5.4 KiB
C++

//===-- PTXISelDAGToDAG.cpp - A dag to dag inst selector for PTX ----------===//
//
// 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 PTX target.
//
//===----------------------------------------------------------------------===//
#include "PTX.h"
#include "PTXTargetMachine.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
namespace {
// PTXDAGToDAGISel - PTX specific code to select PTX machine
// instructions for SelectionDAG operations.
class PTXDAGToDAGISel : public SelectionDAGISel {
public:
PTXDAGToDAGISel(PTXTargetMachine &TM, CodeGenOpt::Level OptLevel);
virtual const char *getPassName() const {
return "PTX DAG->DAG Pattern Instruction Selection";
}
SDNode *Select(SDNode *Node);
// Complex Pattern Selectors.
bool SelectADDRrr(SDValue &Addr, SDValue &R1, SDValue &R2);
bool SelectADDRri(SDValue &Addr, SDValue &Base, SDValue &Offset);
bool SelectADDRii(SDValue &Addr, SDValue &Base, SDValue &Offset);
// Include the pieces auto'gened from the target description
#include "PTXGenDAGISel.inc"
private:
// We need this only because we can't match intruction BRAdp
// pattern (PTXbrcond bb:$d, ...) in PTXInstrInfo.td
SDNode *SelectBRCOND(SDNode *Node);
bool isImm(const SDValue &operand);
bool SelectImm(const SDValue &operand, SDValue &imm);
const PTXSubtarget& getSubtarget() const;
}; // class PTXDAGToDAGISel
} // namespace
// createPTXISelDag - This pass converts a legalized DAG into a
// PTX-specific DAG, ready for instruction scheduling
FunctionPass *llvm::createPTXISelDag(PTXTargetMachine &TM,
CodeGenOpt::Level OptLevel) {
return new PTXDAGToDAGISel(TM, OptLevel);
}
PTXDAGToDAGISel::PTXDAGToDAGISel(PTXTargetMachine &TM,
CodeGenOpt::Level OptLevel)
: SelectionDAGISel(TM, OptLevel) {}
SDNode *PTXDAGToDAGISel::Select(SDNode *Node) {
switch (Node->getOpcode()) {
case ISD::BRCOND:
return SelectBRCOND(Node);
default:
return SelectCode(Node);
}
}
SDNode *PTXDAGToDAGISel::SelectBRCOND(SDNode *Node) {
assert(Node->getNumOperands() >= 3);
SDValue Chain = Node->getOperand(0);
SDValue Pred = Node->getOperand(1);
SDValue Target = Node->getOperand(2); // branch target
SDValue PredOp = CurDAG->getTargetConstant(PTX::PRED_NORMAL, MVT::i32);
DebugLoc dl = Node->getDebugLoc();
assert(Target.getOpcode() == ISD::BasicBlock);
assert(Pred.getValueType() == MVT::i1);
// Emit BRAdp
SDValue Ops[] = { Target, Pred, PredOp, Chain };
return CurDAG->getMachineNode(PTX::BRAdp, dl, MVT::Other, Ops, 4);
}
// Match memory operand of the form [reg+reg]
bool PTXDAGToDAGISel::SelectADDRrr(SDValue &Addr, SDValue &R1, SDValue &R2) {
if (Addr.getOpcode() != ISD::ADD || Addr.getNumOperands() < 2 ||
isImm(Addr.getOperand(0)) || isImm(Addr.getOperand(1)))
return false;
assert(Addr.getValueType().isSimple() && "Type must be simple");
R1 = Addr;
R2 = CurDAG->getTargetConstant(0, Addr.getValueType().getSimpleVT());
return true;
}
// Match memory operand of the form [reg], [imm+reg], and [reg+imm]
bool PTXDAGToDAGISel::SelectADDRri(SDValue &Addr, SDValue &Base,
SDValue &Offset) {
if (Addr.getOpcode() != ISD::ADD) {
// let SelectADDRii handle the [imm] case
if (isImm(Addr))
return false;
// it is [reg]
assert(Addr.getValueType().isSimple() && "Type must be simple");
Base = Addr;
Offset = CurDAG->getTargetConstant(0, Addr.getValueType().getSimpleVT());
return true;
}
if (Addr.getNumOperands() < 2)
return false;
// let SelectADDRii handle the [imm+imm] case
if (isImm(Addr.getOperand(0)) && isImm(Addr.getOperand(1)))
return false;
// try [reg+imm] and [imm+reg]
for (int i = 0; i < 2; i ++)
if (SelectImm(Addr.getOperand(1-i), Offset)) {
Base = Addr.getOperand(i);
return true;
}
// neither [reg+imm] nor [imm+reg]
return false;
}
// Match memory operand of the form [imm+imm] and [imm]
bool PTXDAGToDAGISel::SelectADDRii(SDValue &Addr, SDValue &Base,
SDValue &Offset) {
// is [imm+imm]?
if (Addr.getOpcode() == ISD::ADD) {
return SelectImm(Addr.getOperand(0), Base) &&
SelectImm(Addr.getOperand(1), Offset);
}
// is [imm]?
if (SelectImm(Addr, Base)) {
assert(Addr.getValueType().isSimple() && "Type must be simple");
Offset = CurDAG->getTargetConstant(0, Addr.getValueType().getSimpleVT());
return true;
}
return false;
}
bool PTXDAGToDAGISel::isImm(const SDValue &operand) {
return ConstantSDNode::classof(operand.getNode());
}
bool PTXDAGToDAGISel::SelectImm(const SDValue &operand, SDValue &imm) {
SDNode *node = operand.getNode();
if (!ConstantSDNode::classof(node))
return false;
ConstantSDNode *CN = cast<ConstantSDNode>(node);
imm = CurDAG->getTargetConstant(*CN->getConstantIntValue(),
operand.getValueType());
return true;
}
const PTXSubtarget& PTXDAGToDAGISel::getSubtarget() const
{
return TM.getSubtarget<PTXSubtarget>();
}