Select optimization

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21051 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Andrew Lenharth 2005-04-02 22:32:39 +00:00
parent 0eaf6ce2ef
commit 10c085b525
2 changed files with 143 additions and 56 deletions

View File

@ -335,6 +335,8 @@ public:
void SelectBranchCC(SDOperand N);
void MoveFP2Int(unsigned src, unsigned dst, bool isDouble);
void MoveInt2FP(unsigned src, unsigned dst, bool isDouble);
//returns whether the sense of the comparison was inverted
bool SelectFPSetCC(SDOperand N, unsigned dst);
};
}
@ -418,6 +420,64 @@ void ISel::MoveInt2FP(unsigned src, unsigned dst, bool isDouble)
}
}
bool ISel::SelectFPSetCC(SDOperand N, unsigned dst)
{
SDNode *Node = N.Val;
unsigned Opc, Tmp1, Tmp2, Tmp3;
SetCCSDNode *SetCC = dyn_cast<SetCCSDNode>(Node);
//assert(SetCC->getOperand(0).getValueType() != MVT::f32 && "SetCC f32 should have been promoted");
bool rev = false;
bool inv = false;
switch (SetCC->getCondition()) {
default: Node->dump(); assert(0 && "Unknown FP comparison!");
case ISD::SETEQ: Opc = Alpha::CMPTEQ; break;
case ISD::SETLT: Opc = Alpha::CMPTLT; break;
case ISD::SETLE: Opc = Alpha::CMPTLE; break;
case ISD::SETGT: Opc = Alpha::CMPTLT; rev = true; break;
case ISD::SETGE: Opc = Alpha::CMPTLE; rev = true; break;
case ISD::SETNE: Opc = Alpha::CMPTEQ; inv = true; break;
}
//FIXME: check for constant 0.0
ConstantFPSDNode *CN;
if ((CN = dyn_cast<ConstantFPSDNode>(SetCC->getOperand(0)))
&& (CN->isExactlyValue(+0.0) || CN->isExactlyValue(-0.0)))
Tmp1 = Alpha::F31;
else
Tmp1 = SelectExpr(N.getOperand(0));
if ((CN = dyn_cast<ConstantFPSDNode>(SetCC->getOperand(1)))
&& (CN->isExactlyValue(+0.0) || CN->isExactlyValue(-0.0)))
Tmp2 = Alpha::F31;
else
Tmp2 = SelectExpr(N.getOperand(1));
//Can only compare doubles, and dag won't promote for me
if (SetCC->getOperand(0).getValueType() == MVT::f32)
{
//assert(0 && "Setcc On float?\n");
std::cerr << "Setcc on float!\n";
Tmp3 = MakeReg(MVT::f64);
BuildMI(BB, Alpha::CVTST, 1, Tmp3).addReg(Tmp1);
Tmp1 = Tmp3;
}
if (SetCC->getOperand(1).getValueType() == MVT::f32)
{
//assert (0 && "Setcc On float?\n");
std::cerr << "Setcc on float!\n";
Tmp3 = MakeReg(MVT::f64);
BuildMI(BB, Alpha::CVTST, 1, Tmp3).addReg(Tmp2);
Tmp2 = Tmp3;
}
if (rev) std::swap(Tmp1, Tmp2);
//do the comparison
BuildMI(BB, Opc, 2, dst).addReg(Tmp1).addReg(Tmp2);
return inv;
}
//Check to see if the load is a constant offset from a base register
void ISel::SelectAddr(SDOperand N, unsigned& Reg, long& offset)
{
@ -1318,62 +1378,15 @@ unsigned ISel::SelectExpr(SDOperand N) {
}
}
} else {
//assert(SetCC->getOperand(0).getValueType() != MVT::f32 && "SetCC f32 should have been promoted");
bool rev = false;
bool inv = false;
switch (SetCC->getCondition()) {
default: Node->dump(); assert(0 && "Unknown FP comparison!");
case ISD::SETEQ: Opc = Alpha::CMPTEQ; break;
case ISD::SETLT: Opc = Alpha::CMPTLT; break;
case ISD::SETLE: Opc = Alpha::CMPTLE; break;
case ISD::SETGT: Opc = Alpha::CMPTLT; rev = true; break;
case ISD::SETGE: Opc = Alpha::CMPTLE; rev = true; break;
case ISD::SETNE: Opc = Alpha::CMPTEQ; inv = true; break;
}
//FIXME: check for constant 0.0
ConstantFPSDNode *CN;
if ((CN = dyn_cast<ConstantFPSDNode>(SetCC->getOperand(0)))
&& (CN->isExactlyValue(+0.0) || CN->isExactlyValue(-0.0)))
Tmp1 = Alpha::F31;
else
Tmp1 = SelectExpr(N.getOperand(0));
if ((CN = dyn_cast<ConstantFPSDNode>(SetCC->getOperand(1)))
&& (CN->isExactlyValue(+0.0) || CN->isExactlyValue(-0.0)))
Tmp2 = Alpha::F31;
else
Tmp2 = SelectExpr(N.getOperand(1));
//Can only compare doubles, and dag won't promote for me
if (SetCC->getOperand(0).getValueType() == MVT::f32)
{
//assert(0 && "Setcc On float?\n");
std::cerr << "Setcc on float!\n";
Tmp3 = MakeReg(MVT::f64);
BuildMI(BB, Alpha::CVTST, 1, Tmp3).addReg(Tmp1);
Tmp1 = Tmp3;
}
if (SetCC->getOperand(1).getValueType() == MVT::f32)
{
//assert (0 && "Setcc On float?\n");
std::cerr << "Setcc on float!\n";
Tmp3 = MakeReg(MVT::f64);
BuildMI(BB, Alpha::CVTST, 1, Tmp3).addReg(Tmp2);
Tmp2 = Tmp3;
}
if (rev) std::swap(Tmp1, Tmp2);
Tmp3 = MakeReg(MVT::f64);
//do the comparison
BuildMI(BB, Opc, 2, Tmp3).addReg(Tmp1).addReg(Tmp2);
Tmp1 = MakeReg(MVT::f64);
bool inv = SelectFPSetCC(N, Tmp1);
//now arrange for Result (int) to have a 1 or 0
unsigned Tmp4 = MakeReg(MVT::i64);
BuildMI(BB, Alpha::ADDQi, 2, Tmp4).addReg(Alpha::R31).addImm(1);
Tmp2 = MakeReg(MVT::i64);
BuildMI(BB, Alpha::ADDQi, 2, Tmp2).addReg(Alpha::R31).addImm(1);
Opc = inv?Alpha::CMOVNEi_FP:Alpha::CMOVEQi_FP;
BuildMI(BB, Opc, 3, Result).addReg(Tmp4).addImm(0).addReg(Tmp3);
BuildMI(BB, Opc, 3, Result).addReg(Tmp2).addImm(0).addReg(Tmp1);
}
}
return Result;
@ -1554,16 +1567,88 @@ unsigned ISel::SelectExpr(SDOperand N) {
return Result;
}
// // case ISD::FP_TO_UINT:
case ISD::SELECT:
{
//FIXME: look at parent to decide if intCC can be folded, or if setCC(FP) and can save stack use
Tmp1 = SelectExpr(N.getOperand(0)); //Cond
//Tmp1 = SelectExpr(N.getOperand(0)); //Cond
Tmp2 = SelectExpr(N.getOperand(1)); //Use if TRUE
Tmp3 = SelectExpr(N.getOperand(2)); //Use if FALSE
// Get the condition into the zero flag.
//BuildMI(BB, Alpha::CMOVEQ, 2, Result).addReg(Tmp2).addReg(Tmp3).addReg(Tmp1);
SDOperand CC = N.getOperand(0);
SetCCSDNode* SetCC = dyn_cast<SetCCSDNode>(CC.Val);
if (CC.getOpcode() == ISD::SETCC &&
!MVT::isInteger(SetCC->getOperand(0).getValueType()))
{ //FP Setcc -> Int Select
Tmp1 = MakeReg(MVT::f64);
bool inv = SelectFPSetCC(CC, Tmp1);
BuildMI(BB, inv?Alpha::CMOVNE_FP:Alpha::CMOVEQ_FP, 2, Result)
.addReg(Tmp2).addReg(Tmp3).addReg(Tmp1);
return Result;
}
if (CC.getOpcode() == ISD::SETCC) {
//Int SetCC -> Select
//Dropping the CC is only useful if we are comparing to 0
if(SetCC->getOperand(1).getOpcode() == ISD::Constant &&
cast<ConstantSDNode>(SetCC->getOperand(0))->getValue() == 0)
{
bool useI = (SetCC->getOperand(1).getOpcode() == ISD::Constant &&
cast<ConstantSDNode>(SetCC->getOperand(1))->getValue() <= 255);
switch (SetCC->getCondition()) {
default: CC.Val->dump(); assert(0 && "Unknown integer comparison!");
case ISD::SETEQ: Opc = useI?Alpha::CMOVEQi:Alpha::CMOVEQ; break;
case ISD::SETLT: Opc = useI?Alpha::CMOVGTi:Alpha::CMOVGT; break;
case ISD::SETLE: Opc = useI?Alpha::CMOVGEi:Alpha::CMOVGE; break;
case ISD::SETGT: Opc = useI?Alpha::CMOVLTi:Alpha::CMOVLT; break;
case ISD::SETGE: Opc = useI?Alpha::CMOVLEi:Alpha::CMOVLE; break;
case ISD::SETULT: Opc = useI?Alpha::CMOVNEi:Alpha::CMOVNE; break;
case ISD::SETUGT: assert(0 && "0 > (unsigned) x is never true"); break;
case ISD::SETULE: assert(0 && "0 <= (unsigned) x is always true"); break;
case ISD::SETUGE: Opc = useI?Alpha::CMOVEQi:Alpha::CMOVEQ; break; //Technically you could have this CC
case ISD::SETNE: Opc = useI?Alpha::CMOVNEi:Alpha::CMOVNE; break;
}
if (useI)
BuildMI(BB, Opc, 2, Result).addReg(Tmp2).addReg(Tmp3)
.addImm(cast<ConstantSDNode>(SetCC->getOperand(1))->getValue());
else
BuildMI(BB, Opc, 2, Result).addReg(Tmp2).addReg(Tmp3)
.addReg(SelectExpr(SetCC->getOperand(1)));
return Result;
}
if(SetCC->getOperand(1).getOpcode() == ISD::Constant &&
cast<ConstantSDNode>(SetCC->getOperand(1))->getValue() == 0)
{
bool useI = (SetCC->getOperand(0).getOpcode() == ISD::Constant &&
cast<ConstantSDNode>(SetCC->getOperand(0))->getValue() <= 255);
switch (SetCC->getCondition()) {
default: CC.Val->dump(); assert(0 && "Unknown integer comparison!");
case ISD::SETEQ: Opc = useI?Alpha::CMOVEQi:Alpha::CMOVEQ; break;
case ISD::SETLT: Opc = useI?Alpha::CMOVLTi:Alpha::CMOVLT; break;
case ISD::SETLE: Opc = useI?Alpha::CMOVLEi:Alpha::CMOVLE; break;
case ISD::SETGT: Opc = useI?Alpha::CMOVGTi:Alpha::CMOVGT; break;
case ISD::SETGE: Opc = useI?Alpha::CMOVGEi:Alpha::CMOVGE; break;
case ISD::SETULT: assert(0 && "x (unsigned) < 0 is never true"); break;
case ISD::SETUGT: Opc = useI?Alpha::CMOVNEi:Alpha::CMOVNE; break;
case ISD::SETULE: Opc = useI?Alpha::CMOVEQi:Alpha::CMOVEQ; break; //Technically you could have this CC
case ISD::SETUGE: assert(0 && "x (unsgined >= 0 is always true"); break;
case ISD::SETNE: Opc = useI?Alpha::CMOVNEi:Alpha::CMOVNE; break;
}
if (useI)
BuildMI(BB, Opc, 2, Result).addReg(Tmp2).addReg(Tmp3)
.addImm(cast<ConstantSDNode>(SetCC->getOperand(0))->getValue());
else
BuildMI(BB, Opc, 2, Result).addReg(Tmp2).addReg(Tmp3)
.addReg(SelectExpr(SetCC->getOperand(0)));
return Result;
}
//Otherwise, fall though
}
Tmp1 = SelectExpr(N.getOperand(0)); //Cond
BuildMI(BB, Alpha::CMOVEQ, 2, Result).addReg(Tmp2).addReg(Tmp3).addReg(Tmp1);
return Result;
}

View File

@ -55,6 +55,7 @@ let isCall = 1,
let isReturn = 1, isTerminator = 1 in
def RETURN : PseudoInstAlpha<(ops ), "ret $$31,($$26),1">; //Return from subroutine
//These are evil as they get expanded into multiple instructions to take care of reallocation
let Uses = [R29], Defs = [R28] in {
def LOAD_ADDR : PseudoInstAlpha<(ops GPRC:$RA, s64imm:$DISP), "lda $RA,$DISP">; //Load address
def LDQ_SYM : PseudoInstAlpha<(ops GPRC:$RA, s64imm:$DISP), "ldq $RA,$DISP">; //Load quadword
@ -80,6 +81,7 @@ let Uses = [R29], Defs = [R28] in {
//RESULTS of these go to R27
//These are also evil as the assembler expands them into calls
let Uses = [R29],
Defs = [R28, R23, R24, R25, R27] in
{