llvm-6502/lib/Target/IA64/IA64ISelDAGToDAG.cpp
Dan Gohman e8be6c6391 Add a new function, ReplaceAllUsesOfValuesWith, which handles bulk
replacement of multiple values. This is slightly more efficient
than doing multiple ReplaceAllUsesOfValueWith calls, and theoretically
could be optimized even further. However, an important property of this
new function is that it handles the case where the source value set and
destination value set overlap. This makes it feasible for isel to use
SelectNodeTo in many very common cases, which is advantageous because
SelectNodeTo avoids a temporary node and it doesn't require CSEMap
updates for users of values that don't change position.

Revamp MorphNodeTo, which is what does all the work of SelectNodeTo, to
handle operand lists more efficiently, and to correctly handle a number
of corner cases to which its new wider use exposes it.

This commit also includes a change to the encoding of post-isel opcodes
in SDNodes; now instead of being sandwiched between the target-independent
pre-isel opcodes and the target-dependent pre-isel opcodes, post-isel
opcodes are now represented as negative values. This makes it possible
to test if an opcode is pre-isel or post-isel without having to know
the size of the current target's post-isel instruction set.

These changes speed up llc overall by 3% and reduce memory usage by 10%
on the InstructionCombining.cpp testcase with -fast and -regalloc=local.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53728 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-17 19:10:17 +00:00

589 lines
22 KiB
C++

//===---- IA64ISelDAGToDAG.cpp - IA64 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 IA64,
// converting a legalized dag to an IA64 dag.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "ia64-codegen"
#include "IA64.h"
#include "IA64TargetMachine.h"
#include "IA64ISelLowering.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Constants.h"
#include "llvm/GlobalValue.h"
#include "llvm/Intrinsics.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include <queue>
#include <set>
using namespace llvm;
namespace {
//===--------------------------------------------------------------------===//
/// IA64DAGToDAGISel - IA64 specific code to select IA64 machine
/// instructions for SelectionDAG operations.
///
class IA64DAGToDAGISel : public SelectionDAGISel {
IA64TargetLowering IA64Lowering;
unsigned GlobalBaseReg;
public:
explicit IA64DAGToDAGISel(IA64TargetMachine &TM)
: SelectionDAGISel(IA64Lowering), IA64Lowering(*TM.getTargetLowering()) {}
virtual bool runOnFunction(Function &Fn) {
// Make sure we re-emit a set of the global base reg if necessary
GlobalBaseReg = 0;
return SelectionDAGISel::runOnFunction(Fn);
}
/// getI64Imm - Return a target constant with the specified value, of type
/// i64.
inline SDOperand getI64Imm(uint64_t Imm) {
return CurDAG->getTargetConstant(Imm, MVT::i64);
}
/// getGlobalBaseReg - insert code into the entry mbb to materialize the PIC
/// base register. Return the virtual register that holds this value.
// SDOperand getGlobalBaseReg(); TODO: hmm
// Select - Convert the specified operand from a target-independent to a
// target-specific node if it hasn't already been changed.
SDNode *Select(SDOperand N);
SDNode *SelectIntImmediateExpr(SDOperand LHS, SDOperand RHS,
unsigned OCHi, unsigned OCLo,
bool IsArithmetic = false,
bool Negate = false);
SDNode *SelectBitfieldInsert(SDNode *N);
/// SelectCC - Select a comparison of the specified values with the
/// specified condition code, returning the CR# of the expression.
SDOperand SelectCC(SDOperand LHS, SDOperand RHS, ISD::CondCode CC);
/// SelectAddr - Given the specified address, return the two operands for a
/// load/store instruction, and return true if it should be an indexed [r+r]
/// operation.
bool SelectAddr(SDOperand Addr, SDOperand &Op1, SDOperand &Op2);
/// InstructionSelect - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
virtual void InstructionSelect(SelectionDAG &DAG);
virtual const char *getPassName() const {
return "IA64 (Itanium) DAG->DAG Instruction Selector";
}
// Include the pieces autogenerated from the target description.
#include "IA64GenDAGISel.inc"
private:
SDNode *SelectDIV(SDOperand Op);
};
}
/// InstructionSelect - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
void IA64DAGToDAGISel::InstructionSelect(SelectionDAG &DAG) {
DEBUG(BB->dump());
// Select target instructions for the DAG.
DAG.setRoot(SelectRoot(DAG.getRoot()));
DAG.RemoveDeadNodes();
}
SDNode *IA64DAGToDAGISel::SelectDIV(SDOperand Op) {
SDNode *N = Op.Val;
SDOperand Chain = N->getOperand(0);
SDOperand Tmp1 = N->getOperand(0);
SDOperand Tmp2 = N->getOperand(1);
AddToISelQueue(Chain);
AddToISelQueue(Tmp1);
AddToISelQueue(Tmp2);
bool isFP=false;
if(Tmp1.getValueType().isFloatingPoint())
isFP=true;
bool isModulus=false; // is it a division or a modulus?
bool isSigned=false;
switch(N->getOpcode()) {
case ISD::FDIV:
case ISD::SDIV: isModulus=false; isSigned=true; break;
case ISD::UDIV: isModulus=false; isSigned=false; break;
case ISD::FREM:
case ISD::SREM: isModulus=true; isSigned=true; break;
case ISD::UREM: isModulus=true; isSigned=false; break;
}
// TODO: check for integer divides by powers of 2 (or other simple patterns?)
SDOperand TmpPR, TmpPR2;
SDOperand TmpF1, TmpF2, TmpF3, TmpF4, TmpF5, TmpF6, TmpF7, TmpF8;
SDOperand TmpF9, TmpF10,TmpF11,TmpF12,TmpF13,TmpF14,TmpF15;
SDNode *Result;
// we'll need copies of F0 and F1
SDOperand F0 = CurDAG->getRegister(IA64::F0, MVT::f64);
SDOperand F1 = CurDAG->getRegister(IA64::F1, MVT::f64);
// OK, emit some code:
if(!isFP) {
// first, load the inputs into FP regs.
TmpF1 =
SDOperand(CurDAG->getTargetNode(IA64::SETFSIG, MVT::f64, Tmp1), 0);
Chain = TmpF1.getValue(1);
TmpF2 =
SDOperand(CurDAG->getTargetNode(IA64::SETFSIG, MVT::f64, Tmp2), 0);
Chain = TmpF2.getValue(1);
// next, convert the inputs to FP
if(isSigned) {
TmpF3 =
SDOperand(CurDAG->getTargetNode(IA64::FCVTXF, MVT::f64, TmpF1), 0);
Chain = TmpF3.getValue(1);
TmpF4 =
SDOperand(CurDAG->getTargetNode(IA64::FCVTXF, MVT::f64, TmpF2), 0);
Chain = TmpF4.getValue(1);
} else { // is unsigned
TmpF3 =
SDOperand(CurDAG->getTargetNode(IA64::FCVTXUFS1, MVT::f64, TmpF1), 0);
Chain = TmpF3.getValue(1);
TmpF4 =
SDOperand(CurDAG->getTargetNode(IA64::FCVTXUFS1, MVT::f64, TmpF2), 0);
Chain = TmpF4.getValue(1);
}
} else { // this is an FP divide/remainder, so we 'leak' some temp
// regs and assign TmpF3=Tmp1, TmpF4=Tmp2
TmpF3=Tmp1;
TmpF4=Tmp2;
}
// we start by computing an approximate reciprocal (good to 9 bits?)
// note, this instruction writes _both_ TmpF5 (answer) and TmpPR (predicate)
if(isFP)
TmpF5 = SDOperand(CurDAG->getTargetNode(IA64::FRCPAS0, MVT::f64, MVT::i1,
TmpF3, TmpF4), 0);
else
TmpF5 = SDOperand(CurDAG->getTargetNode(IA64::FRCPAS1, MVT::f64, MVT::i1,
TmpF3, TmpF4), 0);
TmpPR = TmpF5.getValue(1);
Chain = TmpF5.getValue(2);
SDOperand minusB;
if(isModulus) { // for remainders, it'll be handy to have
// copies of -input_b
minusB = SDOperand(CurDAG->getTargetNode(IA64::SUB, MVT::i64,
CurDAG->getRegister(IA64::r0, MVT::i64), Tmp2), 0);
Chain = minusB.getValue(1);
}
SDOperand TmpE0, TmpY1, TmpE1, TmpY2;
SDOperand OpsE0[] = { TmpF4, TmpF5, F1, TmpPR };
TmpE0 = SDOperand(CurDAG->getTargetNode(IA64::CFNMAS1, MVT::f64,
OpsE0, 4), 0);
Chain = TmpE0.getValue(1);
SDOperand OpsY1[] = { TmpF5, TmpE0, TmpF5, TmpPR };
TmpY1 = SDOperand(CurDAG->getTargetNode(IA64::CFMAS1, MVT::f64,
OpsY1, 4), 0);
Chain = TmpY1.getValue(1);
SDOperand OpsE1[] = { TmpE0, TmpE0, F0, TmpPR };
TmpE1 = SDOperand(CurDAG->getTargetNode(IA64::CFMAS1, MVT::f64,
OpsE1, 4), 0);
Chain = TmpE1.getValue(1);
SDOperand OpsY2[] = { TmpY1, TmpE1, TmpY1, TmpPR };
TmpY2 = SDOperand(CurDAG->getTargetNode(IA64::CFMAS1, MVT::f64,
OpsY2, 4), 0);
Chain = TmpY2.getValue(1);
if(isFP) { // if this is an FP divide, we finish up here and exit early
if(isModulus)
assert(0 && "Sorry, try another FORTRAN compiler.");
SDOperand TmpE2, TmpY3, TmpQ0, TmpR0;
SDOperand OpsE2[] = { TmpE1, TmpE1, F0, TmpPR };
TmpE2 = SDOperand(CurDAG->getTargetNode(IA64::CFMAS1, MVT::f64,
OpsE2, 4), 0);
Chain = TmpE2.getValue(1);
SDOperand OpsY3[] = { TmpY2, TmpE2, TmpY2, TmpPR };
TmpY3 = SDOperand(CurDAG->getTargetNode(IA64::CFMAS1, MVT::f64,
OpsY3, 4), 0);
Chain = TmpY3.getValue(1);
SDOperand OpsQ0[] = { Tmp1, TmpY3, F0, TmpPR };
TmpQ0 =
SDOperand(CurDAG->getTargetNode(IA64::CFMADS1, MVT::f64, // double prec!
OpsQ0, 4), 0);
Chain = TmpQ0.getValue(1);
SDOperand OpsR0[] = { Tmp2, TmpQ0, Tmp1, TmpPR };
TmpR0 =
SDOperand(CurDAG->getTargetNode(IA64::CFNMADS1, MVT::f64, // double prec!
OpsR0, 4), 0);
Chain = TmpR0.getValue(1);
// we want Result to have the same target register as the frcpa, so
// we two-address hack it. See the comment "for this to work..." on
// page 48 of Intel application note #245415
SDOperand Ops[] = { TmpF5, TmpY3, TmpR0, TmpQ0, TmpPR };
Result = CurDAG->getTargetNode(IA64::TCFMADS0, MVT::f64, // d.p. s0 rndg!
Ops, 5);
Chain = SDOperand(Result, 1);
return Result; // XXX: early exit!
} else { // this is *not* an FP divide, so there's a bit left to do:
SDOperand TmpQ2, TmpR2, TmpQ3, TmpQ;
SDOperand OpsQ2[] = { TmpF3, TmpY2, F0, TmpPR };
TmpQ2 = SDOperand(CurDAG->getTargetNode(IA64::CFMAS1, MVT::f64,
OpsQ2, 4), 0);
Chain = TmpQ2.getValue(1);
SDOperand OpsR2[] = { TmpF4, TmpQ2, TmpF3, TmpPR };
TmpR2 = SDOperand(CurDAG->getTargetNode(IA64::CFNMAS1, MVT::f64,
OpsR2, 4), 0);
Chain = TmpR2.getValue(1);
// we want TmpQ3 to have the same target register as the frcpa? maybe we
// should two-address hack it. See the comment "for this to work..." on page
// 48 of Intel application note #245415
SDOperand OpsQ3[] = { TmpF5, TmpR2, TmpY2, TmpQ2, TmpPR };
TmpQ3 = SDOperand(CurDAG->getTargetNode(IA64::TCFMAS1, MVT::f64,
OpsQ3, 5), 0);
Chain = TmpQ3.getValue(1);
// STORY: without these two-address instructions (TCFMAS1 and TCFMADS0)
// the FPSWA won't be able to help out in the case of large/tiny
// arguments. Other fun bugs may also appear, e.g. 0/x = x, not 0.
if(isSigned)
TmpQ = SDOperand(CurDAG->getTargetNode(IA64::FCVTFXTRUNCS1,
MVT::f64, TmpQ3), 0);
else
TmpQ = SDOperand(CurDAG->getTargetNode(IA64::FCVTFXUTRUNCS1,
MVT::f64, TmpQ3), 0);
Chain = TmpQ.getValue(1);
if(isModulus) {
SDOperand FPminusB =
SDOperand(CurDAG->getTargetNode(IA64::SETFSIG, MVT::f64, minusB), 0);
Chain = FPminusB.getValue(1);
SDOperand Remainder =
SDOperand(CurDAG->getTargetNode(IA64::XMAL, MVT::f64,
TmpQ, FPminusB, TmpF1), 0);
Chain = Remainder.getValue(1);
Result = CurDAG->getTargetNode(IA64::GETFSIG, MVT::i64, Remainder);
Chain = SDOperand(Result, 1);
} else { // just an integer divide
Result = CurDAG->getTargetNode(IA64::GETFSIG, MVT::i64, TmpQ);
Chain = SDOperand(Result, 1);
}
return Result;
} // wasn't an FP divide
}
// Select - Convert the specified operand from a target-independent to a
// target-specific node if it hasn't already been changed.
SDNode *IA64DAGToDAGISel::Select(SDOperand Op) {
SDNode *N = Op.Val;
if (N->isMachineOpcode())
return NULL; // Already selected.
switch (N->getOpcode()) {
default: break;
case IA64ISD::BRCALL: { // XXX: this is also a hack!
SDOperand Chain = N->getOperand(0);
SDOperand InFlag; // Null incoming flag value.
AddToISelQueue(Chain);
if(N->getNumOperands()==3) { // we have an incoming chain, callee and flag
InFlag = N->getOperand(2);
AddToISelQueue(InFlag);
}
unsigned CallOpcode;
SDOperand CallOperand;
// if we can call directly, do so
if (GlobalAddressSDNode *GASD =
dyn_cast<GlobalAddressSDNode>(N->getOperand(1))) {
CallOpcode = IA64::BRCALL_IPREL_GA;
CallOperand = CurDAG->getTargetGlobalAddress(GASD->getGlobal(), MVT::i64);
} else if (isa<ExternalSymbolSDNode>(N->getOperand(1))) {
// FIXME: we currently NEED this case for correctness, to avoid
// "non-pic code with imm reloc.n against dynamic symbol" errors
CallOpcode = IA64::BRCALL_IPREL_ES;
CallOperand = N->getOperand(1);
} else {
// otherwise we need to load the function descriptor,
// load the branch target (function)'s entry point and GP,
// branch (call) then restore the GP
SDOperand FnDescriptor = N->getOperand(1);
AddToISelQueue(FnDescriptor);
// load the branch target's entry point [mem] and
// GP value [mem+8]
SDOperand targetEntryPoint=
SDOperand(CurDAG->getTargetNode(IA64::LD8, MVT::i64, MVT::Other,
FnDescriptor, CurDAG->getEntryNode()), 0);
Chain = targetEntryPoint.getValue(1);
SDOperand targetGPAddr=
SDOperand(CurDAG->getTargetNode(IA64::ADDS, MVT::i64,
FnDescriptor,
CurDAG->getConstant(8, MVT::i64)), 0);
Chain = targetGPAddr.getValue(1);
SDOperand targetGP =
SDOperand(CurDAG->getTargetNode(IA64::LD8, MVT::i64,MVT::Other,
targetGPAddr, CurDAG->getEntryNode()), 0);
Chain = targetGP.getValue(1);
Chain = CurDAG->getCopyToReg(Chain, IA64::r1, targetGP, InFlag);
InFlag = Chain.getValue(1);
Chain = CurDAG->getCopyToReg(Chain, IA64::B6, targetEntryPoint, InFlag); // FLAG these?
InFlag = Chain.getValue(1);
CallOperand = CurDAG->getRegister(IA64::B6, MVT::i64);
CallOpcode = IA64::BRCALL_INDIRECT;
}
// Finally, once everything is setup, emit the call itself
if(InFlag.Val)
Chain = SDOperand(CurDAG->getTargetNode(CallOpcode, MVT::Other, MVT::Flag,
CallOperand, InFlag), 0);
else // there might be no arguments
Chain = SDOperand(CurDAG->getTargetNode(CallOpcode, MVT::Other, MVT::Flag,
CallOperand, Chain), 0);
InFlag = Chain.getValue(1);
std::vector<SDOperand> CallResults;
CallResults.push_back(Chain);
CallResults.push_back(InFlag);
for (unsigned i = 0, e = CallResults.size(); i != e; ++i)
ReplaceUses(Op.getValue(i), CallResults[i]);
return NULL;
}
case IA64ISD::GETFD: {
SDOperand Input = N->getOperand(0);
AddToISelQueue(Input);
return CurDAG->getTargetNode(IA64::GETFD, MVT::i64, Input);
}
case ISD::FDIV:
case ISD::SDIV:
case ISD::UDIV:
case ISD::SREM:
case ISD::UREM:
return SelectDIV(Op);
case ISD::TargetConstantFP: {
SDOperand Chain = CurDAG->getEntryNode(); // this is a constant, so..
SDOperand V;
ConstantFPSDNode* N2 = cast<ConstantFPSDNode>(N);
if (N2->getValueAPF().isPosZero()) {
V = CurDAG->getCopyFromReg(Chain, IA64::F0, MVT::f64);
} else if (N2->isExactlyValue(N2->getValueType(0) == MVT::f32 ?
APFloat(+1.0f) : APFloat(+1.0))) {
V = CurDAG->getCopyFromReg(Chain, IA64::F1, MVT::f64);
} else
assert(0 && "Unexpected FP constant!");
ReplaceUses(SDOperand(N, 0), V);
return 0;
}
case ISD::FrameIndex: { // TODO: reduce creepyness
int FI = cast<FrameIndexSDNode>(N)->getIndex();
if (N->hasOneUse())
return CurDAG->SelectNodeTo(N, IA64::MOV, MVT::i64,
CurDAG->getTargetFrameIndex(FI, MVT::i64));
else
return CurDAG->getTargetNode(IA64::MOV, MVT::i64,
CurDAG->getTargetFrameIndex(FI, MVT::i64));
}
case ISD::ConstantPool: { // TODO: nuke the constant pool
// (ia64 doesn't need one)
ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(N);
Constant *C = CP->getConstVal();
SDOperand CPI = CurDAG->getTargetConstantPool(C, MVT::i64,
CP->getAlignment());
return CurDAG->getTargetNode(IA64::ADDL_GA, MVT::i64, // ?
CurDAG->getRegister(IA64::r1, MVT::i64), CPI);
}
case ISD::GlobalAddress: {
GlobalValue *GV = cast<GlobalAddressSDNode>(N)->getGlobal();
SDOperand GA = CurDAG->getTargetGlobalAddress(GV, MVT::i64);
SDOperand Tmp =
SDOperand(CurDAG->getTargetNode(IA64::ADDL_GA, MVT::i64,
CurDAG->getRegister(IA64::r1,
MVT::i64), GA), 0);
return CurDAG->getTargetNode(IA64::LD8, MVT::i64, MVT::Other, Tmp,
CurDAG->getEntryNode());
}
/* XXX
case ISD::ExternalSymbol: {
SDOperand EA = CurDAG->getTargetExternalSymbol(
cast<ExternalSymbolSDNode>(N)->getSymbol(),
MVT::i64);
SDOperand Tmp = CurDAG->getTargetNode(IA64::ADDL_EA, MVT::i64,
CurDAG->getRegister(IA64::r1,
MVT::i64),
EA);
return CurDAG->getTargetNode(IA64::LD8, MVT::i64, Tmp);
}
*/
case ISD::LOAD: { // FIXME: load -1, not 1, for bools?
LoadSDNode *LD = cast<LoadSDNode>(N);
SDOperand Chain = LD->getChain();
SDOperand Address = LD->getBasePtr();
AddToISelQueue(Chain);
AddToISelQueue(Address);
MVT TypeBeingLoaded = LD->getMemoryVT();
unsigned Opc;
switch (TypeBeingLoaded.getSimpleVT()) {
default:
#ifndef NDEBUG
N->dump(CurDAG);
#endif
assert(0 && "Cannot load this type!");
case MVT::i1: { // this is a bool
Opc = IA64::LD1; // first we load a byte, then compare for != 0
if(N->getValueType(0) == MVT::i1) { // XXX: early exit!
return CurDAG->SelectNodeTo(N, IA64::CMPNE, MVT::i1, MVT::Other,
SDOperand(CurDAG->getTargetNode(Opc, MVT::i64, Address), 0),
CurDAG->getRegister(IA64::r0, MVT::i64),
Chain);
}
/* otherwise, we want to load a bool into something bigger: LD1
will do that for us, so we just fall through */
}
case MVT::i8: Opc = IA64::LD1; break;
case MVT::i16: Opc = IA64::LD2; break;
case MVT::i32: Opc = IA64::LD4; break;
case MVT::i64: Opc = IA64::LD8; break;
case MVT::f32: Opc = IA64::LDF4; break;
case MVT::f64: Opc = IA64::LDF8; break;
}
// TODO: comment this
return CurDAG->SelectNodeTo(N, Opc, N->getValueType(0), MVT::Other,
Address, Chain);
}
case ISD::STORE: {
StoreSDNode *ST = cast<StoreSDNode>(N);
SDOperand Address = ST->getBasePtr();
SDOperand Chain = ST->getChain();
AddToISelQueue(Address);
AddToISelQueue(Chain);
unsigned Opc;
if (ISD::isNON_TRUNCStore(N)) {
switch (N->getOperand(1).getValueType().getSimpleVT()) {
default: assert(0 && "unknown type in store");
case MVT::i1: { // this is a bool
Opc = IA64::ST1; // we store either 0 or 1 as a byte
// first load zero!
SDOperand Initial = CurDAG->getCopyFromReg(Chain, IA64::r0, MVT::i64);
Chain = Initial.getValue(1);
// then load 1 into the same reg iff the predicate to store is 1
SDOperand Tmp = ST->getValue();
AddToISelQueue(Tmp);
Tmp =
SDOperand(CurDAG->getTargetNode(IA64::TPCADDS, MVT::i64, Initial,
CurDAG->getTargetConstant(1, MVT::i64),
Tmp), 0);
return CurDAG->SelectNodeTo(N, Opc, MVT::Other, Address, Tmp, Chain);
}
case MVT::i64: Opc = IA64::ST8; break;
case MVT::f64: Opc = IA64::STF8; break;
}
} else { // Truncating store
switch(ST->getMemoryVT().getSimpleVT()) {
default: assert(0 && "unknown type in truncstore");
case MVT::i8: Opc = IA64::ST1; break;
case MVT::i16: Opc = IA64::ST2; break;
case MVT::i32: Opc = IA64::ST4; break;
case MVT::f32: Opc = IA64::STF4; break;
}
}
SDOperand N1 = N->getOperand(1);
SDOperand N2 = N->getOperand(2);
AddToISelQueue(N1);
AddToISelQueue(N2);
return CurDAG->SelectNodeTo(N, Opc, MVT::Other, N2, N1, Chain);
}
case ISD::BRCOND: {
SDOperand Chain = N->getOperand(0);
SDOperand CC = N->getOperand(1);
AddToISelQueue(Chain);
AddToISelQueue(CC);
MachineBasicBlock *Dest =
cast<BasicBlockSDNode>(N->getOperand(2))->getBasicBlock();
//FIXME - we do NOT need long branches all the time
return CurDAG->SelectNodeTo(N, IA64::BRLCOND_NOTCALL, MVT::Other, CC,
CurDAG->getBasicBlock(Dest), Chain);
}
case ISD::CALLSEQ_START:
case ISD::CALLSEQ_END: {
int64_t Amt = cast<ConstantSDNode>(N->getOperand(1))->getValue();
unsigned Opc = N->getOpcode() == ISD::CALLSEQ_START ?
IA64::ADJUSTCALLSTACKDOWN : IA64::ADJUSTCALLSTACKUP;
SDOperand N0 = N->getOperand(0);
AddToISelQueue(N0);
return CurDAG->SelectNodeTo(N, Opc, MVT::Other, getI64Imm(Amt), N0);
}
case ISD::BR:
// FIXME: we don't need long branches all the time!
SDOperand N0 = N->getOperand(0);
AddToISelQueue(N0);
return CurDAG->SelectNodeTo(N, IA64::BRL_NOTCALL, MVT::Other,
N->getOperand(1), N0);
}
return SelectCode(Op);
}
/// createIA64DAGToDAGInstructionSelector - This pass converts a legalized DAG
/// into an IA64-specific DAG, ready for instruction scheduling.
///
FunctionPass
*llvm::createIA64DAGToDAGInstructionSelector(IA64TargetMachine &TM) {
return new IA64DAGToDAGISel(TM);
}