llvm-6502/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
Nate Begeman 4a95945fa5 Add the ability to lower return instructions to TargetLowering. This
allows us to lower legal return types to something else, to meet ABI
requirements (such as that i64 be returned in two i32 regs on Darwin/ppc).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23802 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-18 23:23:37 +00:00

1493 lines
57 KiB
C++

//===-- PPCISelDAGToDAG.cpp - PPC --pattern matching inst selector --------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines a pattern matching instruction selector for PowerPC,
// converting from a legalized dag to a PPC dag.
//
//===----------------------------------------------------------------------===//
#include "PPC.h"
#include "PPCTargetMachine.h"
#include "PPCISelLowering.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/SSARegMap.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Constants.h"
#include "llvm/GlobalValue.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
using namespace llvm;
namespace {
Statistic<> FusedFP ("ppc-codegen", "Number of fused fp operations");
Statistic<> FrameOff("ppc-codegen", "Number of frame idx offsets collapsed");
//===--------------------------------------------------------------------===//
/// PPCDAGToDAGISel - PPC specific code to select PPC machine
/// instructions for SelectionDAG operations.
///
class PPCDAGToDAGISel : public SelectionDAGISel {
PPCTargetLowering PPCLowering;
unsigned GlobalBaseReg;
public:
PPCDAGToDAGISel(TargetMachine &TM)
: SelectionDAGISel(PPCLowering), PPCLowering(TM) {}
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);
}
/// getI32Imm - Return a target constant with the specified value, of type
/// i32.
inline SDOperand getI32Imm(unsigned Imm) {
return CurDAG->getTargetConstant(Imm, MVT::i32);
}
/// getGlobalBaseReg - insert code into the entry mbb to materialize the PIC
/// base register. Return the virtual register that holds this value.
SDOperand getGlobalBaseReg();
// Select - Convert the specified operand from a target-independent to a
// target-specific node if it hasn't already been changed.
SDOperand Select(SDOperand Op);
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);
SDOperand BuildSDIVSequence(SDNode *N);
SDOperand BuildUDIVSequence(SDNode *N);
/// InstructionSelectBasicBlock - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
virtual void InstructionSelectBasicBlock(SelectionDAG &DAG);
virtual const char *getPassName() const {
return "PowerPC DAG->DAG Pattern Instruction Selection";
}
// Include the pieces autogenerated from the target description.
#include "PPCGenDAGISel.inc"
private:
SDOperand SelectDYNAMIC_STACKALLOC(SDOperand Op);
SDOperand SelectADD_PARTS(SDOperand Op);
SDOperand SelectSUB_PARTS(SDOperand Op);
SDOperand SelectSETCC(SDOperand Op);
SDOperand SelectCALL(SDOperand Op);
};
}
/// InstructionSelectBasicBlock - This callback is invoked by
/// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
void PPCDAGToDAGISel::InstructionSelectBasicBlock(SelectionDAG &DAG) {
DEBUG(BB->dump());
// The selection process is inherently a bottom-up recursive process (users
// select their uses before themselves). Given infinite stack space, we
// could just start selecting on the root and traverse the whole graph. In
// practice however, this causes us to run out of stack space on large basic
// blocks. To avoid this problem, select the entry node, then all its uses,
// iteratively instead of recursively.
std::vector<SDOperand> Worklist;
Worklist.push_back(DAG.getEntryNode());
// Note that we can do this in the PPC target (scanning forward across token
// chain edges) because no nodes ever get folded across these edges. On a
// target like X86 which supports load/modify/store operations, this would
// have to be more careful.
while (!Worklist.empty()) {
SDOperand Node = Worklist.back();
Worklist.pop_back();
// Chose from the least deep of the top two nodes.
if (!Worklist.empty() &&
Worklist.back().Val->getNodeDepth() < Node.Val->getNodeDepth())
std::swap(Worklist.back(), Node);
if ((Node.Val->getOpcode() >= ISD::BUILTIN_OP_END &&
Node.Val->getOpcode() < PPCISD::FIRST_NUMBER) ||
CodeGenMap.count(Node)) continue;
for (SDNode::use_iterator UI = Node.Val->use_begin(),
E = Node.Val->use_end(); UI != E; ++UI) {
// Scan the values. If this use has a value that is a token chain, add it
// to the worklist.
SDNode *User = *UI;
for (unsigned i = 0, e = User->getNumValues(); i != e; ++i)
if (User->getValueType(i) == MVT::Other) {
Worklist.push_back(SDOperand(User, i));
break;
}
}
// Finally, legalize this node.
Select(Node);
}
// Select target instructions for the DAG.
DAG.setRoot(Select(DAG.getRoot()));
CodeGenMap.clear();
DAG.RemoveDeadNodes();
// Emit machine code to BB.
ScheduleAndEmitDAG(DAG);
}
/// getGlobalBaseReg - Output the instructions required to put the
/// base address to use for accessing globals into a register.
///
SDOperand PPCDAGToDAGISel::getGlobalBaseReg() {
if (!GlobalBaseReg) {
// Insert the set of GlobalBaseReg into the first MBB of the function
MachineBasicBlock &FirstMBB = BB->getParent()->front();
MachineBasicBlock::iterator MBBI = FirstMBB.begin();
SSARegMap *RegMap = BB->getParent()->getSSARegMap();
// FIXME: when we get to LP64, we will need to create the appropriate
// type of register here.
GlobalBaseReg = RegMap->createVirtualRegister(PPC::GPRCRegisterClass);
BuildMI(FirstMBB, MBBI, PPC::MovePCtoLR, 0, PPC::LR);
BuildMI(FirstMBB, MBBI, PPC::MFLR, 1, GlobalBaseReg);
}
return CurDAG->getRegister(GlobalBaseReg, MVT::i32);
}
// isIntImmediate - This method tests to see if a constant operand.
// If so Imm will receive the 32 bit value.
static bool isIntImmediate(SDNode *N, unsigned& Imm) {
if (N->getOpcode() == ISD::Constant) {
Imm = cast<ConstantSDNode>(N)->getValue();
return true;
}
return false;
}
// isOprShiftImm - Returns true if the specified operand is a shift opcode with
// a immediate shift count less than 32.
static bool isOprShiftImm(SDNode *N, unsigned& Opc, unsigned& SH) {
Opc = N->getOpcode();
return (Opc == ISD::SHL || Opc == ISD::SRL || Opc == ISD::SRA) &&
isIntImmediate(N->getOperand(1).Val, SH) && SH < 32;
}
// isRunOfOnes - Returns true iff Val consists of one contiguous run of 1s with
// any number of 0s on either side. The 1s are allowed to wrap from LSB to
// MSB, so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. 0x0F0F0000 is
// not, since all 1s are not contiguous.
static bool isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME) {
if (isShiftedMask_32(Val)) {
// look for the first non-zero bit
MB = CountLeadingZeros_32(Val);
// look for the first zero bit after the run of ones
ME = CountLeadingZeros_32((Val - 1) ^ Val);
return true;
} else {
Val = ~Val; // invert mask
if (isShiftedMask_32(Val)) {
// effectively look for the first zero bit
ME = CountLeadingZeros_32(Val) - 1;
// effectively look for the first one bit after the run of zeros
MB = CountLeadingZeros_32((Val - 1) ^ Val) + 1;
return true;
}
}
// no run present
return false;
}
// isRotateAndMask - Returns true if Mask and Shift can be folded into a rotate
// and mask opcode and mask operation.
static bool isRotateAndMask(SDNode *N, unsigned Mask, bool IsShiftMask,
unsigned &SH, unsigned &MB, unsigned &ME) {
unsigned Shift = 32;
unsigned Indeterminant = ~0; // bit mask marking indeterminant results
unsigned Opcode = N->getOpcode();
if (N->getNumOperands() != 2 ||
!isIntImmediate(N->getOperand(1).Val, Shift) || (Shift > 31))
return false;
if (Opcode == ISD::SHL) {
// apply shift left to mask if it comes first
if (IsShiftMask) Mask = Mask << Shift;
// determine which bits are made indeterminant by shift
Indeterminant = ~(0xFFFFFFFFu << Shift);
} else if (Opcode == ISD::SRL) {
// apply shift right to mask if it comes first
if (IsShiftMask) Mask = Mask >> Shift;
// determine which bits are made indeterminant by shift
Indeterminant = ~(0xFFFFFFFFu >> Shift);
// adjust for the left rotate
Shift = 32 - Shift;
} else {
return false;
}
// if the mask doesn't intersect any Indeterminant bits
if (Mask && !(Mask & Indeterminant)) {
SH = Shift;
// make sure the mask is still a mask (wrap arounds may not be)
return isRunOfOnes(Mask, MB, ME);
}
return false;
}
// isOpcWithIntImmediate - This method tests to see if the node is a specific
// opcode and that it has a immediate integer right operand.
// If so Imm will receive the 32 bit value.
static bool isOpcWithIntImmediate(SDNode *N, unsigned Opc, unsigned& Imm) {
return N->getOpcode() == Opc && isIntImmediate(N->getOperand(1).Val, Imm);
}
// isOprNot - Returns true if the specified operand is an xor with immediate -1.
static bool isOprNot(SDNode *N) {
unsigned Imm;
return isOpcWithIntImmediate(N, ISD::XOR, Imm) && (signed)Imm == -1;
}
// Immediate constant composers.
// Lo16 - grabs the lo 16 bits from a 32 bit constant.
// Hi16 - grabs the hi 16 bits from a 32 bit constant.
// HA16 - computes the hi bits required if the lo bits are add/subtracted in
// arithmethically.
static unsigned Lo16(unsigned x) { return x & 0x0000FFFF; }
static unsigned Hi16(unsigned x) { return Lo16(x >> 16); }
static unsigned HA16(unsigned x) { return Hi16((signed)x - (signed short)x); }
// isIntImmediate - This method tests to see if a constant operand.
// If so Imm will receive the 32 bit value.
static bool isIntImmediate(SDOperand N, unsigned& Imm) {
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N)) {
Imm = (unsigned)CN->getSignExtended();
return true;
}
return false;
}
/// SelectBitfieldInsert - turn an or of two masked values into
/// the rotate left word immediate then mask insert (rlwimi) instruction.
/// Returns true on success, false if the caller still needs to select OR.
///
/// Patterns matched:
/// 1. or shl, and 5. or and, and
/// 2. or and, shl 6. or shl, shr
/// 3. or shr, and 7. or shr, shl
/// 4. or and, shr
SDNode *PPCDAGToDAGISel::SelectBitfieldInsert(SDNode *N) {
bool IsRotate = false;
unsigned TgtMask = 0xFFFFFFFF, InsMask = 0xFFFFFFFF, SH = 0;
unsigned Value;
SDOperand Op0 = N->getOperand(0);
SDOperand Op1 = N->getOperand(1);
unsigned Op0Opc = Op0.getOpcode();
unsigned Op1Opc = Op1.getOpcode();
// Verify that we have the correct opcodes
if (ISD::SHL != Op0Opc && ISD::SRL != Op0Opc && ISD::AND != Op0Opc)
return false;
if (ISD::SHL != Op1Opc && ISD::SRL != Op1Opc && ISD::AND != Op1Opc)
return false;
// Generate Mask value for Target
if (isIntImmediate(Op0.getOperand(1), Value)) {
switch(Op0Opc) {
case ISD::SHL: TgtMask <<= Value; break;
case ISD::SRL: TgtMask >>= Value; break;
case ISD::AND: TgtMask &= Value; break;
}
} else {
return 0;
}
// Generate Mask value for Insert
if (!isIntImmediate(Op1.getOperand(1), Value))
return 0;
switch(Op1Opc) {
case ISD::SHL:
SH = Value;
InsMask <<= SH;
if (Op0Opc == ISD::SRL) IsRotate = true;
break;
case ISD::SRL:
SH = Value;
InsMask >>= SH;
SH = 32-SH;
if (Op0Opc == ISD::SHL) IsRotate = true;
break;
case ISD::AND:
InsMask &= Value;
break;
}
// If both of the inputs are ANDs and one of them has a logical shift by
// constant as its input, make that AND the inserted value so that we can
// combine the shift into the rotate part of the rlwimi instruction
bool IsAndWithShiftOp = false;
if (Op0Opc == ISD::AND && Op1Opc == ISD::AND) {
if (Op1.getOperand(0).getOpcode() == ISD::SHL ||
Op1.getOperand(0).getOpcode() == ISD::SRL) {
if (isIntImmediate(Op1.getOperand(0).getOperand(1), Value)) {
SH = Op1.getOperand(0).getOpcode() == ISD::SHL ? Value : 32 - Value;
IsAndWithShiftOp = true;
}
} else if (Op0.getOperand(0).getOpcode() == ISD::SHL ||
Op0.getOperand(0).getOpcode() == ISD::SRL) {
if (isIntImmediate(Op0.getOperand(0).getOperand(1), Value)) {
std::swap(Op0, Op1);
std::swap(TgtMask, InsMask);
SH = Op1.getOperand(0).getOpcode() == ISD::SHL ? Value : 32 - Value;
IsAndWithShiftOp = true;
}
}
}
// Verify that the Target mask and Insert mask together form a full word mask
// and that the Insert mask is a run of set bits (which implies both are runs
// of set bits). Given that, Select the arguments and generate the rlwimi
// instruction.
unsigned MB, ME;
if (((TgtMask & InsMask) == 0) && isRunOfOnes(InsMask, MB, ME)) {
bool fullMask = (TgtMask ^ InsMask) == 0xFFFFFFFF;
bool Op0IsAND = Op0Opc == ISD::AND;
// Check for rotlwi / rotrwi here, a special case of bitfield insert
// where both bitfield halves are sourced from the same value.
if (IsRotate && fullMask &&
N->getOperand(0).getOperand(0) == N->getOperand(1).getOperand(0)) {
Op0 = CurDAG->getTargetNode(PPC::RLWINM, MVT::i32,
Select(N->getOperand(0).getOperand(0)),
getI32Imm(SH), getI32Imm(0), getI32Imm(31));
return Op0.Val;
}
SDOperand Tmp1 = (Op0IsAND && fullMask) ? Select(Op0.getOperand(0))
: Select(Op0);
SDOperand Tmp2 = IsAndWithShiftOp ? Select(Op1.getOperand(0).getOperand(0))
: Select(Op1.getOperand(0));
Op0 = CurDAG->getTargetNode(PPC::RLWIMI, MVT::i32, Tmp1, Tmp2,
getI32Imm(SH), getI32Imm(MB), getI32Imm(ME));
return Op0.Val;
}
return 0;
}
/// 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 PPCDAGToDAGISel::SelectAddr(SDOperand Addr, SDOperand &Op1,
SDOperand &Op2) {
unsigned imm = 0;
if (Addr.getOpcode() == ISD::ADD) {
if (isIntImmediate(Addr.getOperand(1), imm) && isInt16(imm)) {
Op1 = getI32Imm(Lo16(imm));
if (FrameIndexSDNode *FI =
dyn_cast<FrameIndexSDNode>(Addr.getOperand(0))) {
++FrameOff;
Op2 = CurDAG->getTargetFrameIndex(FI->getIndex(), MVT::i32);
} else {
Op2 = Select(Addr.getOperand(0));
}
return false;
} else {
Op1 = Select(Addr.getOperand(0));
Op2 = Select(Addr.getOperand(1));
return true; // [r+r]
}
}
// Now check if we're dealing with a global, and whether or not we should emit
// an optimized load or store for statics.
if (GlobalAddressSDNode *GN = dyn_cast<GlobalAddressSDNode>(Addr)) {
GlobalValue *GV = GN->getGlobal();
if (!GV->hasWeakLinkage() && !GV->isExternal()) {
Op1 = CurDAG->getTargetGlobalAddress(GV, MVT::i32);
if (PICEnabled)
Op2 = CurDAG->getTargetNode(PPC::ADDIS, MVT::i32, getGlobalBaseReg(),
Op1);
else
Op2 = CurDAG->getTargetNode(PPC::LIS, MVT::i32, Op1);
return false;
}
} else if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(Addr)) {
Op1 = getI32Imm(0);
Op2 = CurDAG->getTargetFrameIndex(FI->getIndex(), MVT::i32);
return false;
} else if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(Addr)) {
Op1 = Addr;
if (PICEnabled)
Op2 = CurDAG->getTargetNode(PPC::ADDIS, MVT::i32, getGlobalBaseReg(),Op1);
else
Op2 = CurDAG->getTargetNode(PPC::LIS, MVT::i32, Op1);
return false;
}
Op1 = getI32Imm(0);
Op2 = Select(Addr);
return false;
}
/// SelectCC - Select a comparison of the specified values with the specified
/// condition code, returning the CR# of the expression.
SDOperand PPCDAGToDAGISel::SelectCC(SDOperand LHS, SDOperand RHS,
ISD::CondCode CC) {
// Always select the LHS.
LHS = Select(LHS);
// Use U to determine whether the SETCC immediate range is signed or not.
if (MVT::isInteger(LHS.getValueType())) {
bool U = ISD::isUnsignedIntSetCC(CC);
unsigned Imm;
if (isIntImmediate(RHS, Imm) &&
((U && isUInt16(Imm)) || (!U && isInt16(Imm))))
return CurDAG->getTargetNode(U ? PPC::CMPLWI : PPC::CMPWI, MVT::i32,
LHS, getI32Imm(Lo16(Imm)));
return CurDAG->getTargetNode(U ? PPC::CMPLW : PPC::CMPW, MVT::i32,
LHS, Select(RHS));
} else if (LHS.getValueType() == MVT::f32) {
return CurDAG->getTargetNode(PPC::FCMPUS, MVT::i32, LHS, Select(RHS));
} else {
return CurDAG->getTargetNode(PPC::FCMPUD, MVT::i32, LHS, Select(RHS));
}
}
/// getBCCForSetCC - Returns the PowerPC condition branch mnemonic corresponding
/// to Condition.
static unsigned getBCCForSetCC(ISD::CondCode CC) {
switch (CC) {
default: assert(0 && "Unknown condition!"); abort();
case ISD::SETEQ: return PPC::BEQ;
case ISD::SETNE: return PPC::BNE;
case ISD::SETULT:
case ISD::SETLT: return PPC::BLT;
case ISD::SETULE:
case ISD::SETLE: return PPC::BLE;
case ISD::SETUGT:
case ISD::SETGT: return PPC::BGT;
case ISD::SETUGE:
case ISD::SETGE: return PPC::BGE;
}
return 0;
}
/// getCRIdxForSetCC - Return the index of the condition register field
/// associated with the SetCC condition, and whether or not the field is
/// treated as inverted. That is, lt = 0; ge = 0 inverted.
static unsigned getCRIdxForSetCC(ISD::CondCode CC, bool& Inv) {
switch (CC) {
default: assert(0 && "Unknown condition!"); abort();
case ISD::SETULT:
case ISD::SETLT: Inv = false; return 0;
case ISD::SETUGE:
case ISD::SETGE: Inv = true; return 0;
case ISD::SETUGT:
case ISD::SETGT: Inv = false; return 1;
case ISD::SETULE:
case ISD::SETLE: Inv = true; return 1;
case ISD::SETEQ: Inv = false; return 2;
case ISD::SETNE: Inv = true; return 2;
}
return 0;
}
// Structure used to return the necessary information to codegen an SDIV as
// a multiply.
struct ms {
int m; // magic number
int s; // shift amount
};
struct mu {
unsigned int m; // magic number
int a; // add indicator
int s; // shift amount
};
/// magic - calculate the magic numbers required to codegen an integer sdiv as
/// a sequence of multiply and shifts. Requires that the divisor not be 0, 1,
/// or -1.
static struct ms magic(int d) {
int p;
unsigned int ad, anc, delta, q1, r1, q2, r2, t;
const unsigned int two31 = 0x80000000U;
struct ms mag;
ad = abs(d);
t = two31 + ((unsigned int)d >> 31);
anc = t - 1 - t%ad; // absolute value of nc
p = 31; // initialize p
q1 = two31/anc; // initialize q1 = 2p/abs(nc)
r1 = two31 - q1*anc; // initialize r1 = rem(2p,abs(nc))
q2 = two31/ad; // initialize q2 = 2p/abs(d)
r2 = two31 - q2*ad; // initialize r2 = rem(2p,abs(d))
do {
p = p + 1;
q1 = 2*q1; // update q1 = 2p/abs(nc)
r1 = 2*r1; // update r1 = rem(2p/abs(nc))
if (r1 >= anc) { // must be unsigned comparison
q1 = q1 + 1;
r1 = r1 - anc;
}
q2 = 2*q2; // update q2 = 2p/abs(d)
r2 = 2*r2; // update r2 = rem(2p/abs(d))
if (r2 >= ad) { // must be unsigned comparison
q2 = q2 + 1;
r2 = r2 - ad;
}
delta = ad - r2;
} while (q1 < delta || (q1 == delta && r1 == 0));
mag.m = q2 + 1;
if (d < 0) mag.m = -mag.m; // resulting magic number
mag.s = p - 32; // resulting shift
return mag;
}
/// magicu - calculate the magic numbers required to codegen an integer udiv as
/// a sequence of multiply, add and shifts. Requires that the divisor not be 0.
static struct mu magicu(unsigned d)
{
int p;
unsigned int nc, delta, q1, r1, q2, r2;
struct mu magu;
magu.a = 0; // initialize "add" indicator
nc = - 1 - (-d)%d;
p = 31; // initialize p
q1 = 0x80000000/nc; // initialize q1 = 2p/nc
r1 = 0x80000000 - q1*nc; // initialize r1 = rem(2p,nc)
q2 = 0x7FFFFFFF/d; // initialize q2 = (2p-1)/d
r2 = 0x7FFFFFFF - q2*d; // initialize r2 = rem((2p-1),d)
do {
p = p + 1;
if (r1 >= nc - r1 ) {
q1 = 2*q1 + 1; // update q1
r1 = 2*r1 - nc; // update r1
}
else {
q1 = 2*q1; // update q1
r1 = 2*r1; // update r1
}
if (r2 + 1 >= d - r2) {
if (q2 >= 0x7FFFFFFF) magu.a = 1;
q2 = 2*q2 + 1; // update q2
r2 = 2*r2 + 1 - d; // update r2
}
else {
if (q2 >= 0x80000000) magu.a = 1;
q2 = 2*q2; // update q2
r2 = 2*r2 + 1; // update r2
}
delta = d - 1 - r2;
} while (p < 64 && (q1 < delta || (q1 == delta && r1 == 0)));
magu.m = q2 + 1; // resulting magic number
magu.s = p - 32; // resulting shift
return magu;
}
/// BuildSDIVSequence - Given an ISD::SDIV node expressing a divide by constant,
/// return a DAG expression to select that will generate the same value by
/// multiplying by a magic number. See:
/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
SDOperand PPCDAGToDAGISel::BuildSDIVSequence(SDNode *N) {
int d = (int)cast<ConstantSDNode>(N->getOperand(1))->getValue();
ms magics = magic(d);
// Multiply the numerator (operand 0) by the magic value
SDOperand Q = CurDAG->getNode(ISD::MULHS, MVT::i32, N->getOperand(0),
CurDAG->getConstant(magics.m, MVT::i32));
// If d > 0 and m < 0, add the numerator
if (d > 0 && magics.m < 0)
Q = CurDAG->getNode(ISD::ADD, MVT::i32, Q, N->getOperand(0));
// If d < 0 and m > 0, subtract the numerator.
if (d < 0 && magics.m > 0)
Q = CurDAG->getNode(ISD::SUB, MVT::i32, Q, N->getOperand(0));
// Shift right algebraic if shift value is nonzero
if (magics.s > 0)
Q = CurDAG->getNode(ISD::SRA, MVT::i32, Q,
CurDAG->getConstant(magics.s, MVT::i32));
// Extract the sign bit and add it to the quotient
SDOperand T =
CurDAG->getNode(ISD::SRL, MVT::i32, Q, CurDAG->getConstant(31, MVT::i32));
return CurDAG->getNode(ISD::ADD, MVT::i32, Q, T);
}
/// BuildUDIVSequence - Given an ISD::UDIV node expressing a divide by constant,
/// return a DAG expression to select that will generate the same value by
/// multiplying by a magic number. See:
/// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html>
SDOperand PPCDAGToDAGISel::BuildUDIVSequence(SDNode *N) {
unsigned d = (unsigned)cast<ConstantSDNode>(N->getOperand(1))->getValue();
mu magics = magicu(d);
// Multiply the numerator (operand 0) by the magic value
SDOperand Q = CurDAG->getNode(ISD::MULHU, MVT::i32, N->getOperand(0),
CurDAG->getConstant(magics.m, MVT::i32));
if (magics.a == 0) {
return CurDAG->getNode(ISD::SRL, MVT::i32, Q,
CurDAG->getConstant(magics.s, MVT::i32));
} else {
SDOperand NPQ = CurDAG->getNode(ISD::SUB, MVT::i32, N->getOperand(0), Q);
NPQ = CurDAG->getNode(ISD::SRL, MVT::i32, NPQ,
CurDAG->getConstant(1, MVT::i32));
NPQ = CurDAG->getNode(ISD::ADD, MVT::i32, NPQ, Q);
return CurDAG->getNode(ISD::SRL, MVT::i32, NPQ,
CurDAG->getConstant(magics.s-1, MVT::i32));
}
}
SDOperand PPCDAGToDAGISel::SelectDYNAMIC_STACKALLOC(SDOperand Op) {
SDNode *N = Op.Val;
// FIXME: We are currently ignoring the requested alignment for handling
// greater than the stack alignment. This will need to be revisited at some
// point. Align = N.getOperand(2);
if (!isa<ConstantSDNode>(N->getOperand(2)) ||
cast<ConstantSDNode>(N->getOperand(2))->getValue() != 0) {
std::cerr << "Cannot allocate stack object with greater alignment than"
<< " the stack alignment yet!";
abort();
}
SDOperand Chain = Select(N->getOperand(0));
SDOperand Amt = Select(N->getOperand(1));
SDOperand R1Reg = CurDAG->getRegister(PPC::R1, MVT::i32);
SDOperand R1Val = CurDAG->getCopyFromReg(Chain, PPC::R1, MVT::i32);
Chain = R1Val.getValue(1);
// Subtract the amount (guaranteed to be a multiple of the stack alignment)
// from the stack pointer, giving us the result pointer.
SDOperand Result = CurDAG->getTargetNode(PPC::SUBF, MVT::i32, Amt, R1Val);
// Copy this result back into R1.
Chain = CurDAG->getNode(ISD::CopyToReg, MVT::Other, Chain, R1Reg, Result);
// Copy this result back out of R1 to make sure we're not using the stack
// space without decrementing the stack pointer.
Result = CurDAG->getCopyFromReg(Chain, PPC::R1, MVT::i32);
// Finally, replace the DYNAMIC_STACKALLOC with the copyfromreg.
CodeGenMap[Op.getValue(0)] = Result;
CodeGenMap[Op.getValue(1)] = Result.getValue(1);
return SDOperand(Result.Val, Op.ResNo);
}
SDOperand PPCDAGToDAGISel::SelectADD_PARTS(SDOperand Op) {
SDNode *N = Op.Val;
SDOperand LHSL = Select(N->getOperand(0));
SDOperand LHSH = Select(N->getOperand(1));
unsigned Imm;
bool ME = false, ZE = false;
if (isIntImmediate(N->getOperand(3), Imm)) {
ME = (signed)Imm == -1;
ZE = Imm == 0;
}
std::vector<SDOperand> Result;
SDOperand CarryFromLo;
if (isIntImmediate(N->getOperand(2), Imm) &&
((signed)Imm >= -32768 || (signed)Imm < 32768)) {
// Codegen the low 32 bits of the add. Interestingly, there is no
// shifted form of add immediate carrying.
CarryFromLo = CurDAG->getTargetNode(PPC::ADDIC, MVT::i32, MVT::Flag,
LHSL, getI32Imm(Imm));
} else {
CarryFromLo = CurDAG->getTargetNode(PPC::ADDC, MVT::i32, MVT::Flag,
LHSL, Select(N->getOperand(2)));
}
CarryFromLo = CarryFromLo.getValue(1);
// Codegen the high 32 bits, adding zero, minus one, or the full value
// along with the carry flag produced by addc/addic.
SDOperand ResultHi;
if (ZE)
ResultHi = CurDAG->getTargetNode(PPC::ADDZE, MVT::i32, LHSH, CarryFromLo);
else if (ME)
ResultHi = CurDAG->getTargetNode(PPC::ADDME, MVT::i32, LHSH, CarryFromLo);
else
ResultHi = CurDAG->getTargetNode(PPC::ADDE, MVT::i32, LHSH,
Select(N->getOperand(3)), CarryFromLo);
Result.push_back(CarryFromLo.getValue(0));
Result.push_back(ResultHi);
CodeGenMap[Op.getValue(0)] = Result[0];
CodeGenMap[Op.getValue(1)] = Result[1];
return Result[Op.ResNo];
}
SDOperand PPCDAGToDAGISel::SelectSUB_PARTS(SDOperand Op) {
SDNode *N = Op.Val;
SDOperand LHSL = Select(N->getOperand(0));
SDOperand LHSH = Select(N->getOperand(1));
SDOperand RHSL = Select(N->getOperand(2));
SDOperand RHSH = Select(N->getOperand(3));
std::vector<SDOperand> Result;
Result.push_back(CurDAG->getTargetNode(PPC::SUBFC, MVT::i32, MVT::Flag,
RHSL, LHSL));
Result.push_back(CurDAG->getTargetNode(PPC::SUBFE, MVT::i32, RHSH, LHSH,
Result[0].getValue(1)));
CodeGenMap[Op.getValue(0)] = Result[0];
CodeGenMap[Op.getValue(1)] = Result[1];
return Result[Op.ResNo];
}
SDOperand PPCDAGToDAGISel::SelectSETCC(SDOperand Op) {
SDNode *N = Op.Val;
unsigned Imm;
ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(2))->get();
if (isIntImmediate(N->getOperand(1), Imm)) {
// We can codegen setcc op, imm very efficiently compared to a brcond.
// Check for those cases here.
// setcc op, 0
if (Imm == 0) {
SDOperand Op = Select(N->getOperand(0));
switch (CC) {
default: assert(0 && "Unhandled SetCC condition"); abort();
case ISD::SETEQ:
Op = CurDAG->getTargetNode(PPC::CNTLZW, MVT::i32, Op);
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Op, getI32Imm(27),
getI32Imm(5), getI32Imm(31));
break;
case ISD::SETNE: {
SDOperand AD = CurDAG->getTargetNode(PPC::ADDIC, MVT::i32, MVT::Flag,
Op, getI32Imm(~0U));
CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, AD, Op, AD.getValue(1));
break;
}
case ISD::SETLT:
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Op, getI32Imm(1),
getI32Imm(31), getI32Imm(31));
break;
case ISD::SETGT: {
SDOperand T = CurDAG->getTargetNode(PPC::NEG, MVT::i32, Op);
T = CurDAG->getTargetNode(PPC::ANDC, MVT::i32, T, Op);;
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, T, getI32Imm(1),
getI32Imm(31), getI32Imm(31));
break;
}
}
return SDOperand(N, 0);
} else if (Imm == ~0U) { // setcc op, -1
SDOperand Op = Select(N->getOperand(0));
switch (CC) {
default: assert(0 && "Unhandled SetCC condition"); abort();
case ISD::SETEQ:
Op = CurDAG->getTargetNode(PPC::ADDIC, MVT::i32, MVT::Flag,
Op, getI32Imm(1));
CurDAG->SelectNodeTo(N, PPC::ADDZE, MVT::i32,
CurDAG->getTargetNode(PPC::LI, MVT::i32,
getI32Imm(0)),
Op.getValue(1));
break;
case ISD::SETNE: {
Op = CurDAG->getTargetNode(PPC::NOR, MVT::i32, Op, Op);
SDOperand AD = CurDAG->getTargetNode(PPC::ADDIC, MVT::i32, MVT::Flag,
Op, getI32Imm(~0U));
CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, AD, Op, AD.getValue(1));
break;
}
case ISD::SETLT: {
SDOperand AD = CurDAG->getTargetNode(PPC::ADDI, MVT::i32, Op,
getI32Imm(1));
SDOperand AN = CurDAG->getTargetNode(PPC::AND, MVT::i32, AD, Op);
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, AN, getI32Imm(1),
getI32Imm(31), getI32Imm(31));
break;
}
case ISD::SETGT:
Op = CurDAG->getTargetNode(PPC::RLWINM, MVT::i32, Op, getI32Imm(1),
getI32Imm(31), getI32Imm(31));
CurDAG->SelectNodeTo(N, PPC::XORI, MVT::i32, Op, getI32Imm(1));
break;
}
return SDOperand(N, 0);
}
}
bool Inv;
unsigned Idx = getCRIdxForSetCC(CC, Inv);
SDOperand CCReg = SelectCC(N->getOperand(0), N->getOperand(1), CC);
SDOperand IntCR;
// Force the ccreg into CR7.
SDOperand CR7Reg = CurDAG->getRegister(PPC::CR7, MVT::i32);
std::vector<MVT::ValueType> VTs;
VTs.push_back(MVT::Other);
VTs.push_back(MVT::Flag); // NONSTANDARD CopyToReg node: defines a flag
std::vector<SDOperand> Ops;
Ops.push_back(CurDAG->getEntryNode());
Ops.push_back(CR7Reg);
Ops.push_back(CCReg);
CCReg = CurDAG->getNode(ISD::CopyToReg, VTs, Ops).getValue(1);
if (TLI.getTargetMachine().getSubtarget<PPCSubtarget>().isGigaProcessor())
IntCR = CurDAG->getTargetNode(PPC::MFOCRF, MVT::i32, CR7Reg, CCReg);
else
IntCR = CurDAG->getTargetNode(PPC::MFCR, MVT::i32, CCReg);
if (!Inv) {
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, IntCR,
getI32Imm(32-(3-Idx)), getI32Imm(31), getI32Imm(31));
} else {
SDOperand Tmp =
CurDAG->getTargetNode(PPC::RLWINM, MVT::i32, IntCR,
getI32Imm(32-(3-Idx)), getI32Imm(31),getI32Imm(31));
CurDAG->SelectNodeTo(N, PPC::XORI, MVT::i32, Tmp, getI32Imm(1));
}
return SDOperand(N, 0);
}
SDOperand PPCDAGToDAGISel::SelectCALL(SDOperand Op) {
SDNode *N = Op.Val;
SDOperand Chain = Select(N->getOperand(0));
unsigned CallOpcode;
std::vector<SDOperand> CallOperands;
if (GlobalAddressSDNode *GASD =
dyn_cast<GlobalAddressSDNode>(N->getOperand(1))) {
CallOpcode = PPC::CALLpcrel;
CallOperands.push_back(CurDAG->getTargetGlobalAddress(GASD->getGlobal(),
MVT::i32));
} else if (ExternalSymbolSDNode *ESSDN =
dyn_cast<ExternalSymbolSDNode>(N->getOperand(1))) {
CallOpcode = PPC::CALLpcrel;
CallOperands.push_back(N->getOperand(1));
} else {
// Copy the callee address into the CTR register.
SDOperand Callee = Select(N->getOperand(1));
Chain = CurDAG->getTargetNode(PPC::MTCTR, MVT::Other, Callee, Chain);
// Copy the callee address into R12 on darwin.
SDOperand R12 = CurDAG->getRegister(PPC::R12, MVT::i32);
Chain = CurDAG->getNode(ISD::CopyToReg, MVT::Other, Chain, R12, Callee);
CallOperands.push_back(getI32Imm(20)); // Information to encode indcall
CallOperands.push_back(getI32Imm(0)); // Information to encode indcall
CallOperands.push_back(R12);
CallOpcode = PPC::CALLindirect;
}
unsigned GPR_idx = 0, FPR_idx = 0;
static const unsigned GPR[] = {
PPC::R3, PPC::R4, PPC::R5, PPC::R6,
PPC::R7, PPC::R8, PPC::R9, PPC::R10,
};
static const unsigned FPR[] = {
PPC::F1, PPC::F2, PPC::F3, PPC::F4, PPC::F5, PPC::F6, PPC::F7,
PPC::F8, PPC::F9, PPC::F10, PPC::F11, PPC::F12, PPC::F13
};
SDOperand InFlag; // Null incoming flag value.
for (unsigned i = 2, e = N->getNumOperands(); i != e; ++i) {
unsigned DestReg = 0;
MVT::ValueType RegTy = N->getOperand(i).getValueType();
if (RegTy == MVT::i32) {
assert(GPR_idx < 8 && "Too many int args");
DestReg = GPR[GPR_idx++];
} else {
assert(MVT::isFloatingPoint(N->getOperand(i).getValueType()) &&
"Unpromoted integer arg?");
assert(FPR_idx < 13 && "Too many fp args");
DestReg = FPR[FPR_idx++];
}
if (N->getOperand(i).getOpcode() != ISD::UNDEF) {
SDOperand Val = Select(N->getOperand(i));
Chain = CurDAG->getCopyToReg(Chain, DestReg, Val, InFlag);
InFlag = Chain.getValue(1);
CallOperands.push_back(CurDAG->getRegister(DestReg, RegTy));
}
}
// Finally, once everything is in registers to pass to the call, emit the
// call itself.
if (InFlag.Val)
CallOperands.push_back(InFlag); // Strong dep on register copies.
else
CallOperands.push_back(Chain); // Weak dep on whatever occurs before
Chain = CurDAG->getTargetNode(CallOpcode, MVT::Other, MVT::Flag,
CallOperands);
std::vector<SDOperand> CallResults;
// If the call has results, copy the values out of the ret val registers.
switch (N->getValueType(0)) {
default: assert(0 && "Unexpected ret value!");
case MVT::Other: break;
case MVT::i32:
if (N->getValueType(1) == MVT::i32) {
Chain = CurDAG->getCopyFromReg(Chain, PPC::R4, MVT::i32,
Chain.getValue(1)).getValue(1);
CallResults.push_back(Chain.getValue(0));
Chain = CurDAG->getCopyFromReg(Chain, PPC::R3, MVT::i32,
Chain.getValue(2)).getValue(1);
CallResults.push_back(Chain.getValue(0));
} else {
Chain = CurDAG->getCopyFromReg(Chain, PPC::R3, MVT::i32,
Chain.getValue(1)).getValue(1);
CallResults.push_back(Chain.getValue(0));
}
break;
case MVT::f32:
case MVT::f64:
Chain = CurDAG->getCopyFromReg(Chain, PPC::F1, N->getValueType(0),
Chain.getValue(1)).getValue(1);
CallResults.push_back(Chain.getValue(0));
break;
}
CallResults.push_back(Chain);
for (unsigned i = 0, e = CallResults.size(); i != e; ++i)
CodeGenMap[Op.getValue(i)] = CallResults[i];
return CallResults[Op.ResNo];
}
// Select - Convert the specified operand from a target-independent to a
// target-specific node if it hasn't already been changed.
SDOperand PPCDAGToDAGISel::Select(SDOperand Op) {
SDNode *N = Op.Val;
if (N->getOpcode() >= ISD::BUILTIN_OP_END &&
N->getOpcode() < PPCISD::FIRST_NUMBER)
return Op; // Already selected.
// If this has already been converted, use it.
std::map<SDOperand, SDOperand>::iterator CGMI = CodeGenMap.find(Op);
if (CGMI != CodeGenMap.end()) return CGMI->second;
switch (N->getOpcode()) {
default: break;
case ISD::DYNAMIC_STACKALLOC: return SelectDYNAMIC_STACKALLOC(Op);
case ISD::ADD_PARTS: return SelectADD_PARTS(Op);
case ISD::SUB_PARTS: return SelectSUB_PARTS(Op);
case ISD::SETCC: return SelectSETCC(Op);
case ISD::CALL: return SelectCALL(Op);
case ISD::TAILCALL: return SelectCALL(Op);
case ISD::TokenFactor: {
SDOperand New;
if (N->getNumOperands() == 2) {
SDOperand Op0 = Select(N->getOperand(0));
SDOperand Op1 = Select(N->getOperand(1));
New = CurDAG->getNode(ISD::TokenFactor, MVT::Other, Op0, Op1);
} else {
std::vector<SDOperand> Ops;
for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
Ops.push_back(Select(N->getOperand(i)));
New = CurDAG->getNode(ISD::TokenFactor, MVT::Other, Ops);
}
CodeGenMap[Op] = New;
return New;
}
case ISD::CopyFromReg: {
SDOperand Chain = Select(N->getOperand(0));
if (Chain == N->getOperand(0)) return Op; // No change
SDOperand New = CurDAG->getCopyFromReg(Chain,
cast<RegisterSDNode>(N->getOperand(1))->getReg(), N->getValueType(0));
return New.getValue(Op.ResNo);
}
case ISD::CopyToReg: {
SDOperand Chain = Select(N->getOperand(0));
SDOperand Reg = N->getOperand(1);
SDOperand Val = Select(N->getOperand(2));
SDOperand New = CurDAG->getNode(ISD::CopyToReg, MVT::Other,
Chain, Reg, Val);
CodeGenMap[Op] = New;
return New;
}
case ISD::UNDEF:
if (N->getValueType(0) == MVT::i32)
CurDAG->SelectNodeTo(N, PPC::IMPLICIT_DEF_GPR, MVT::i32);
else if (N->getValueType(0) == MVT::f32)
CurDAG->SelectNodeTo(N, PPC::IMPLICIT_DEF_F4, MVT::f32);
else
CurDAG->SelectNodeTo(N, PPC::IMPLICIT_DEF_F8, MVT::f64);
return SDOperand(N, 0);
case ISD::FrameIndex: {
int FI = cast<FrameIndexSDNode>(N)->getIndex();
CurDAG->SelectNodeTo(N, PPC::ADDI, MVT::i32,
CurDAG->getTargetFrameIndex(FI, MVT::i32),
getI32Imm(0));
return SDOperand(N, 0);
}
case ISD::ConstantPool: {
Constant *C = cast<ConstantPoolSDNode>(N)->get();
SDOperand Tmp, CPI = CurDAG->getTargetConstantPool(C, MVT::i32);
if (PICEnabled)
Tmp = CurDAG->getTargetNode(PPC::ADDIS, MVT::i32, getGlobalBaseReg(),CPI);
else
Tmp = CurDAG->getTargetNode(PPC::LIS, MVT::i32, CPI);
CurDAG->SelectNodeTo(N, PPC::LA, MVT::i32, Tmp, CPI);
return SDOperand(N, 0);
}
case ISD::GlobalAddress: {
GlobalValue *GV = cast<GlobalAddressSDNode>(N)->getGlobal();
SDOperand Tmp;
SDOperand GA = CurDAG->getTargetGlobalAddress(GV, MVT::i32);
if (PICEnabled)
Tmp = CurDAG->getTargetNode(PPC::ADDIS, MVT::i32, getGlobalBaseReg(), GA);
else
Tmp = CurDAG->getTargetNode(PPC::LIS, MVT::i32, GA);
if (GV->hasWeakLinkage() || GV->isExternal())
CurDAG->SelectNodeTo(N, PPC::LWZ, MVT::i32, GA, Tmp);
else
CurDAG->SelectNodeTo(N, PPC::LA, MVT::i32, Tmp, GA);
return SDOperand(N, 0);
}
case PPCISD::FSEL: {
SDOperand Comparison = Select(N->getOperand(0));
// Extend the comparison to 64-bits.
if (Comparison.getValueType() == MVT::f32)
Comparison = CurDAG->getTargetNode(PPC::FMRSD, MVT::f64, Comparison);
unsigned Opc = N->getValueType(0) == MVT::f32 ? PPC::FSELS : PPC::FSELD;
CurDAG->SelectNodeTo(N, Opc, N->getValueType(0), Comparison,
Select(N->getOperand(1)), Select(N->getOperand(2)));
return SDOperand(N, 0);
}
case PPCISD::FCFID:
CurDAG->SelectNodeTo(N, PPC::FCFID, N->getValueType(0),
Select(N->getOperand(0)));
return SDOperand(N, 0);
case PPCISD::FCTIDZ:
CurDAG->SelectNodeTo(N, PPC::FCTIDZ, N->getValueType(0),
Select(N->getOperand(0)));
return SDOperand(N, 0);
case PPCISD::FCTIWZ:
CurDAG->SelectNodeTo(N, PPC::FCTIWZ, N->getValueType(0),
Select(N->getOperand(0)));
return SDOperand(N, 0);
case ISD::FADD: {
MVT::ValueType Ty = N->getValueType(0);
if (!NoExcessFPPrecision) { // Match FMA ops
if (N->getOperand(0).getOpcode() == ISD::FMUL &&
N->getOperand(0).Val->hasOneUse()) {
++FusedFP; // Statistic
CurDAG->SelectNodeTo(N, Ty == MVT::f64 ? PPC::FMADD : PPC::FMADDS, Ty,
Select(N->getOperand(0).getOperand(0)),
Select(N->getOperand(0).getOperand(1)),
Select(N->getOperand(1)));
return SDOperand(N, 0);
} else if (N->getOperand(1).getOpcode() == ISD::FMUL &&
N->getOperand(1).hasOneUse()) {
++FusedFP; // Statistic
CurDAG->SelectNodeTo(N, Ty == MVT::f64 ? PPC::FMADD : PPC::FMADDS, Ty,
Select(N->getOperand(1).getOperand(0)),
Select(N->getOperand(1).getOperand(1)),
Select(N->getOperand(0)));
return SDOperand(N, 0);
}
}
CurDAG->SelectNodeTo(N, Ty == MVT::f64 ? PPC::FADD : PPC::FADDS, Ty,
Select(N->getOperand(0)), Select(N->getOperand(1)));
return SDOperand(N, 0);
}
case ISD::FSUB: {
MVT::ValueType Ty = N->getValueType(0);
if (!NoExcessFPPrecision) { // Match FMA ops
if (N->getOperand(0).getOpcode() == ISD::FMUL &&
N->getOperand(0).Val->hasOneUse()) {
++FusedFP; // Statistic
CurDAG->SelectNodeTo(N, Ty == MVT::f64 ? PPC::FMSUB : PPC::FMSUBS, Ty,
Select(N->getOperand(0).getOperand(0)),
Select(N->getOperand(0).getOperand(1)),
Select(N->getOperand(1)));
return SDOperand(N, 0);
} else if (N->getOperand(1).getOpcode() == ISD::FMUL &&
N->getOperand(1).Val->hasOneUse()) {
++FusedFP; // Statistic
CurDAG->SelectNodeTo(N, Ty == MVT::f64 ? PPC::FNMSUB : PPC::FNMSUBS, Ty,
Select(N->getOperand(1).getOperand(0)),
Select(N->getOperand(1).getOperand(1)),
Select(N->getOperand(0)));
return SDOperand(N, 0);
}
}
CurDAG->SelectNodeTo(N, Ty == MVT::f64 ? PPC::FSUB : PPC::FSUBS, Ty,
Select(N->getOperand(0)),
Select(N->getOperand(1)));
return SDOperand(N, 0);
}
case ISD::SDIV: {
unsigned Imm;
if (isIntImmediate(N->getOperand(1), Imm)) {
if ((signed)Imm > 0 && isPowerOf2_32(Imm)) {
SDOperand Op =
CurDAG->getTargetNode(PPC::SRAWI, MVT::i32, MVT::Flag,
Select(N->getOperand(0)),
getI32Imm(Log2_32(Imm)));
CurDAG->SelectNodeTo(N, PPC::ADDZE, MVT::i32,
Op.getValue(0), Op.getValue(1));
return SDOperand(N, 0);
} else if ((signed)Imm < 0 && isPowerOf2_32(-Imm)) {
SDOperand Op =
CurDAG->getTargetNode(PPC::SRAWI, MVT::i32, MVT::Flag,
Select(N->getOperand(0)),
getI32Imm(Log2_32(-Imm)));
SDOperand PT =
CurDAG->getTargetNode(PPC::ADDZE, MVT::i32, Op.getValue(0),
Op.getValue(1));
CurDAG->SelectNodeTo(N, PPC::NEG, MVT::i32, PT);
return SDOperand(N, 0);
} else if (Imm) {
SDOperand Result = Select(BuildSDIVSequence(N));
CodeGenMap[Op] = Result;
return Result;
}
}
// Other cases are autogenerated.
break;
}
case ISD::UDIV: {
// If this is a divide by constant, we can emit code using some magic
// constants to implement it as a multiply instead.
unsigned Imm;
if (isIntImmediate(N->getOperand(1), Imm) && Imm) {
SDOperand Result = Select(BuildUDIVSequence(N));
CodeGenMap[Op] = Result;
return Result;
}
// Other cases are autogenerated.
break;
}
case ISD::AND: {
unsigned Imm;
// If this is an and of a value rotated between 0 and 31 bits and then and'd
// with a mask, emit rlwinm
if (isIntImmediate(N->getOperand(1), Imm) && (isShiftedMask_32(Imm) ||
isShiftedMask_32(~Imm))) {
SDOperand Val;
unsigned SH, MB, ME;
if (isRotateAndMask(N->getOperand(0).Val, Imm, false, SH, MB, ME)) {
Val = Select(N->getOperand(0).getOperand(0));
} else {
Val = Select(N->getOperand(0));
isRunOfOnes(Imm, MB, ME);
SH = 0;
}
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Val, getI32Imm(SH),
getI32Imm(MB), getI32Imm(ME));
return SDOperand(N, 0);
}
// Other cases are autogenerated.
break;
}
case ISD::OR:
if (SDNode *I = SelectBitfieldInsert(N))
return CodeGenMap[Op] = SDOperand(I, 0);
// Other cases are autogenerated.
break;
case ISD::ANY_EXTEND:
switch(N->getValueType(0)) {
default: assert(0 && "Unhandled type in ANY_EXTEND");
case MVT::i64:
CurDAG->SelectNodeTo(N, PPC::OR8, MVT::i64, Select(N->getOperand(0)),
Select(N->getOperand(0)));
break;
}
return SDOperand(N, 0);
case ISD::ZERO_EXTEND:
assert(N->getValueType(0) == MVT::i64 &&
N->getOperand(0).getValueType() == MVT::i32 &&
"ZERO_EXTEND only supported for i32 -> i64");
CurDAG->SelectNodeTo(N, PPC::RLDICL, MVT::i64, Select(N->getOperand(0)),
getI32Imm(32));
return SDOperand(N, 0);
case ISD::SHL: {
unsigned Imm, SH, MB, ME;
if (isOpcWithIntImmediate(N->getOperand(0).Val, ISD::AND, Imm) &&
isRotateAndMask(N, Imm, true, SH, MB, ME))
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32,
Select(N->getOperand(0).getOperand(0)),
getI32Imm(SH), getI32Imm(MB), getI32Imm(ME));
else if (isIntImmediate(N->getOperand(1), Imm))
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Select(N->getOperand(0)),
getI32Imm(Imm), getI32Imm(0), getI32Imm(31-Imm));
else
CurDAG->SelectNodeTo(N, PPC::SLW, MVT::i32, Select(N->getOperand(0)),
Select(N->getOperand(1)));
return SDOperand(N, 0);
}
case ISD::SRL: {
unsigned Imm, SH, MB, ME;
if (isOpcWithIntImmediate(N->getOperand(0).Val, ISD::AND, Imm) &&
isRotateAndMask(N, Imm, true, SH, MB, ME))
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32,
Select(N->getOperand(0).getOperand(0)),
getI32Imm(SH & 0x1F), getI32Imm(MB), getI32Imm(ME));
else if (isIntImmediate(N->getOperand(1), Imm))
CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Select(N->getOperand(0)),
getI32Imm((32-Imm) & 0x1F), getI32Imm(Imm),
getI32Imm(31));
else
CurDAG->SelectNodeTo(N, PPC::SRW, MVT::i32, Select(N->getOperand(0)),
Select(N->getOperand(1)));
return SDOperand(N, 0);
}
case ISD::FNEG: {
SDOperand Val = Select(N->getOperand(0));
MVT::ValueType Ty = N->getValueType(0);
if (N->getOperand(0).Val->hasOneUse()) {
unsigned Opc;
switch (Val.isTargetOpcode() ? Val.getTargetOpcode() : 0) {
default: Opc = 0; break;
case PPC::FABSS: Opc = PPC::FNABSS; break;
case PPC::FABSD: Opc = PPC::FNABSD; break;
case PPC::FMADD: Opc = PPC::FNMADD; break;
case PPC::FMADDS: Opc = PPC::FNMADDS; break;
case PPC::FMSUB: Opc = PPC::FNMSUB; break;
case PPC::FMSUBS: Opc = PPC::FNMSUBS; break;
}
// If we inverted the opcode, then emit the new instruction with the
// inverted opcode and the original instruction's operands. Otherwise,
// fall through and generate a fneg instruction.
if (Opc) {
if (Opc == PPC::FNABSS || Opc == PPC::FNABSD)
CurDAG->SelectNodeTo(N, Opc, Ty, Val.getOperand(0));
else
CurDAG->SelectNodeTo(N, Opc, Ty, Val.getOperand(0),
Val.getOperand(1), Val.getOperand(2));
return SDOperand(N, 0);
}
}
if (Ty == MVT::f32)
CurDAG->SelectNodeTo(N, PPC::FNEGS, MVT::f32, Val);
else
CurDAG->SelectNodeTo(N, PPC::FNEGD, MVT::f64, Val);
return SDOperand(N, 0);
}
case ISD::LOAD:
case ISD::EXTLOAD:
case ISD::ZEXTLOAD:
case ISD::SEXTLOAD: {
SDOperand Op1, Op2;
bool isIdx = SelectAddr(N->getOperand(1), Op1, Op2);
MVT::ValueType TypeBeingLoaded = (N->getOpcode() == ISD::LOAD) ?
N->getValueType(0) : cast<VTSDNode>(N->getOperand(3))->getVT();
unsigned Opc;
switch (TypeBeingLoaded) {
default: N->dump(); assert(0 && "Cannot load this type!");
case MVT::i1:
case MVT::i8: Opc = isIdx ? PPC::LBZX : PPC::LBZ; break;
case MVT::i16:
if (N->getOpcode() == ISD::SEXTLOAD) { // SEXT load?
Opc = isIdx ? PPC::LHAX : PPC::LHA;
} else {
Opc = isIdx ? PPC::LHZX : PPC::LHZ;
}
break;
case MVT::i32: Opc = isIdx ? PPC::LWZX : PPC::LWZ; break;
case MVT::f32: Opc = isIdx ? PPC::LFSX : PPC::LFS; break;
case MVT::f64: Opc = isIdx ? PPC::LFDX : PPC::LFD; break;
}
// If this is an f32 -> f64 load, emit the f32 load, then use an 'extending
// copy'.
if (TypeBeingLoaded != MVT::f32 || N->getOpcode() == ISD::LOAD) {
CurDAG->SelectNodeTo(N, Opc, N->getValueType(0), MVT::Other,
Op1, Op2, Select(N->getOperand(0)));
return SDOperand(N, Op.ResNo);
} else {
std::vector<SDOperand> Ops;
Ops.push_back(Op1);
Ops.push_back(Op2);
Ops.push_back(Select(N->getOperand(0)));
SDOperand Res = CurDAG->getTargetNode(Opc, MVT::f32, MVT::Other, Ops);
SDOperand Ext = CurDAG->getTargetNode(PPC::FMRSD, MVT::f64, Res);
CodeGenMap[Op.getValue(0)] = Ext;
CodeGenMap[Op.getValue(1)] = Res.getValue(1);
if (Op.ResNo)
return Res.getValue(1);
else
return Ext;
}
}
case ISD::TRUNCSTORE:
case ISD::STORE: {
SDOperand AddrOp1, AddrOp2;
bool isIdx = SelectAddr(N->getOperand(2), AddrOp1, AddrOp2);
unsigned Opc;
if (N->getOpcode() == ISD::STORE) {
switch (N->getOperand(1).getValueType()) {
default: assert(0 && "unknown Type in store");
case MVT::i32: Opc = isIdx ? PPC::STWX : PPC::STW; break;
case MVT::f64: Opc = isIdx ? PPC::STFDX : PPC::STFD; break;
case MVT::f32: Opc = isIdx ? PPC::STFSX : PPC::STFS; break;
}
} else { //ISD::TRUNCSTORE
switch(cast<VTSDNode>(N->getOperand(4))->getVT()) {
default: assert(0 && "unknown Type in store");
case MVT::i8: Opc = isIdx ? PPC::STBX : PPC::STB; break;
case MVT::i16: Opc = isIdx ? PPC::STHX : PPC::STH; break;
}
}
CurDAG->SelectNodeTo(N, Opc, MVT::Other, Select(N->getOperand(1)),
AddrOp1, AddrOp2, Select(N->getOperand(0)));
return SDOperand(N, 0);
}
case ISD::SELECT_CC: {
ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(4))->get();
// handle the setcc cases here. select_cc lhs, 0, 1, 0, cc
if (ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N->getOperand(1)))
if (ConstantSDNode *N2C = dyn_cast<ConstantSDNode>(N->getOperand(2)))
if (ConstantSDNode *N3C = dyn_cast<ConstantSDNode>(N->getOperand(3)))
if (N1C->isNullValue() && N3C->isNullValue() &&
N2C->getValue() == 1ULL && CC == ISD::SETNE) {
SDOperand LHS = Select(N->getOperand(0));
SDOperand Tmp =
CurDAG->getTargetNode(PPC::ADDIC, MVT::i32, MVT::Flag,
LHS, getI32Imm(~0U));
CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, Tmp, LHS,
Tmp.getValue(1));
return SDOperand(N, 0);
}
SDOperand CCReg = SelectCC(N->getOperand(0), N->getOperand(1), CC);
unsigned BROpc = getBCCForSetCC(CC);
bool isFP = MVT::isFloatingPoint(N->getValueType(0));
unsigned SelectCCOp;
if (MVT::isInteger(N->getValueType(0)))
SelectCCOp = PPC::SELECT_CC_Int;
else if (N->getValueType(0) == MVT::f32)
SelectCCOp = PPC::SELECT_CC_F4;
else
SelectCCOp = PPC::SELECT_CC_F8;
CurDAG->SelectNodeTo(N, SelectCCOp, N->getValueType(0), CCReg,
Select(N->getOperand(2)), Select(N->getOperand(3)),
getI32Imm(BROpc));
return SDOperand(N, 0);
}
case ISD::CALLSEQ_START:
case ISD::CALLSEQ_END: {
unsigned Amt = cast<ConstantSDNode>(N->getOperand(1))->getValue();
unsigned Opc = N->getOpcode() == ISD::CALLSEQ_START ?
PPC::ADJCALLSTACKDOWN : PPC::ADJCALLSTACKUP;
CurDAG->SelectNodeTo(N, Opc, MVT::Other,
getI32Imm(Amt), Select(N->getOperand(0)));
return SDOperand(N, 0);
}
case ISD::RET: {
SDOperand Chain = Select(N->getOperand(0)); // Token chain.
if (N->getNumOperands() == 2) {
SDOperand Val = Select(N->getOperand(1));
if (N->getOperand(1).getValueType() == MVT::i32) {
Chain = CurDAG->getCopyToReg(Chain, PPC::R3, Val);
} else {
assert(MVT::isFloatingPoint(N->getOperand(1).getValueType()));
Chain = CurDAG->getCopyToReg(Chain, PPC::F1, Val);
}
} else if (N->getNumOperands() > 1) {
assert(N->getOperand(1).getValueType() == MVT::i32 &&
N->getOperand(2).getValueType() == MVT::i32 &&
N->getNumOperands() == 3 && "Unknown two-register ret value!");
Chain = CurDAG->getCopyToReg(Chain, PPC::R4, Select(N->getOperand(1)));
Chain = CurDAG->getCopyToReg(Chain, PPC::R3, Select(N->getOperand(2)));
}
// Finally, select this to a blr (return) instruction.
CurDAG->SelectNodeTo(N, PPC::BLR, MVT::Other, Chain);
return SDOperand(N, 0);
}
case ISD::BR:
CurDAG->SelectNodeTo(N, PPC::B, MVT::Other, N->getOperand(1),
Select(N->getOperand(0)));
return SDOperand(N, 0);
case ISD::BR_CC:
case ISD::BRTWOWAY_CC: {
SDOperand Chain = Select(N->getOperand(0));
MachineBasicBlock *Dest =
cast<BasicBlockSDNode>(N->getOperand(4))->getBasicBlock();
ISD::CondCode CC = cast<CondCodeSDNode>(N->getOperand(1))->get();
SDOperand CondCode = SelectCC(N->getOperand(2), N->getOperand(3), CC);
// If this is a two way branch, then grab the fallthrough basic block
// argument and build a PowerPC branch pseudo-op, suitable for long branch
// conversion if necessary by the branch selection pass. Otherwise, emit a
// standard conditional branch.
if (N->getOpcode() == ISD::BRTWOWAY_CC) {
SDOperand CondTrueBlock = N->getOperand(4);
SDOperand CondFalseBlock = N->getOperand(5);
// If the false case is the current basic block, then this is a self loop.
// We do not want to emit "Loop: ... brcond Out; br Loop", as it adds an
// extra dispatch group to the loop. Instead, invert the condition and
// emit "Loop: ... br!cond Loop; br Out
if (cast<BasicBlockSDNode>(CondFalseBlock)->getBasicBlock() == BB) {
std::swap(CondTrueBlock, CondFalseBlock);
CC = getSetCCInverse(CC,
MVT::isInteger(N->getOperand(2).getValueType()));
}
unsigned Opc = getBCCForSetCC(CC);
SDOperand CB = CurDAG->getTargetNode(PPC::COND_BRANCH, MVT::Other,
CondCode, getI32Imm(Opc),
CondTrueBlock, CondFalseBlock,
Chain);
CurDAG->SelectNodeTo(N, PPC::B, MVT::Other, CondFalseBlock, CB);
} else {
// Iterate to the next basic block
ilist<MachineBasicBlock>::iterator It = BB;
++It;
// If the fallthrough path is off the end of the function, which would be
// undefined behavior, set it to be the same as the current block because
// we have nothing better to set it to, and leaving it alone will cause
// the PowerPC Branch Selection pass to crash.
if (It == BB->getParent()->end()) It = Dest;
CurDAG->SelectNodeTo(N, PPC::COND_BRANCH, MVT::Other, CondCode,
getI32Imm(getBCCForSetCC(CC)), N->getOperand(4),
CurDAG->getBasicBlock(It), Chain);
}
return SDOperand(N, 0);
}
}
return SelectCode(Op);
}
/// createPPCISelDag - This pass converts a legalized DAG into a
/// PowerPC-specific DAG, ready for instruction scheduling.
///
FunctionPass *llvm::createPPCISelDag(TargetMachine &TM) {
return new PPCDAGToDAGISel(TM);
}