FastISel: constrain the RegClass of operands when emitting instructions.

ARM64 suffered multiple -verify-machineinstr failures (principally over the
xsp/xzr issue) because FastISel was completely ignoring which subset of the
general-purpose registers each instruction required.

More fixes are coming in ARM64 specific FastISel, but this should cover the
generic problems.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206283 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Tim Northover 2014-04-15 13:59:49 +00:00
parent f90c8c7063
commit 03eecdccff
3 changed files with 53 additions and 27 deletions

View File

@ -343,6 +343,12 @@ protected:
unsigned createResultReg(const TargetRegisterClass *RC);
/// Try to constrain Op so that it is usable by argument OpNum of the provided
/// MCInstrDesc. If this fails, create a new virtual register in the correct
/// class and COPY the value there.
unsigned constrainOperandRegClass(const MCInstrDesc &II, unsigned Op,
unsigned OpNum);
/// Emit a constant in a register using target-specific logic, such as
/// constant pool loads.
virtual unsigned TargetMaterializeConstant(const Constant* C) {

View File

@ -1204,6 +1204,23 @@ unsigned FastISel::createResultReg(const TargetRegisterClass* RC) {
return MRI.createVirtualRegister(RC);
}
unsigned FastISel::constrainOperandRegClass(const MCInstrDesc &II,
unsigned Op, unsigned OpNum) {
if (TargetRegisterInfo::isVirtualRegister(Op)) {
const TargetRegisterClass *RegClass =
TII.getRegClass(II, OpNum, &TRI, *FuncInfo.MF);
if (!MRI.constrainRegClass(Op, RegClass)) {
// If it's not legal to COPY between the register classes, something
// has gone very wrong before we got here.
unsigned NewOp = createResultReg(RegClass);
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(TargetOpcode::COPY), NewOp).addReg(Op);
return NewOp;
}
}
return Op;
}
unsigned FastISel::FastEmitInst_(unsigned MachineInstOpcode,
const TargetRegisterClass* RC) {
unsigned ResultReg = createResultReg(RC);
@ -1216,9 +1233,11 @@ unsigned FastISel::FastEmitInst_(unsigned MachineInstOpcode,
unsigned FastISel::FastEmitInst_r(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill) {
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
unsigned ResultReg = createResultReg(RC);
Op0 = constrainOperandRegClass(II, Op0, II.getNumDefs());
if (II.getNumDefs() >= 1)
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill);
@ -1236,9 +1255,12 @@ unsigned FastISel::FastEmitInst_rr(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
unsigned Op1, bool Op1IsKill) {
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
unsigned ResultReg = createResultReg(RC);
Op0 = constrainOperandRegClass(II, Op0, II.getNumDefs());
Op1 = constrainOperandRegClass(II, Op1, II.getNumDefs() + 1);
if (II.getNumDefs() >= 1)
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -1258,9 +1280,13 @@ unsigned FastISel::FastEmitInst_rrr(unsigned MachineInstOpcode,
unsigned Op0, bool Op0IsKill,
unsigned Op1, bool Op1IsKill,
unsigned Op2, bool Op2IsKill) {
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
unsigned ResultReg = createResultReg(RC);
Op0 = constrainOperandRegClass(II, Op0, II.getNumDefs());
Op1 = constrainOperandRegClass(II, Op1, II.getNumDefs() + 1);
Op2 = constrainOperandRegClass(II, Op2, II.getNumDefs() + 2);
if (II.getNumDefs() >= 1)
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -1281,9 +1307,12 @@ unsigned FastISel::FastEmitInst_ri(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
uint64_t Imm) {
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
unsigned ResultReg = createResultReg(RC);
RC = TII.getRegClass(II, II.getNumDefs(), &TRI, *FuncInfo.MF);
MRI.constrainRegClass(Op0, RC);
if (II.getNumDefs() >= 1)
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -1302,9 +1331,11 @@ unsigned FastISel::FastEmitInst_rii(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
uint64_t Imm1, uint64_t Imm2) {
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
unsigned ResultReg = createResultReg(RC);
Op0 = constrainOperandRegClass(II, Op0, II.getNumDefs());
if (II.getNumDefs() >= 1)
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -1325,9 +1356,11 @@ unsigned FastISel::FastEmitInst_rf(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill,
const ConstantFP *FPImm) {
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
unsigned ResultReg = createResultReg(RC);
Op0 = constrainOperandRegClass(II, Op0, II.getNumDefs());
if (II.getNumDefs() >= 1)
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -1347,9 +1380,12 @@ unsigned FastISel::FastEmitInst_rri(unsigned MachineInstOpcode,
unsigned Op0, bool Op0IsKill,
unsigned Op1, bool Op1IsKill,
uint64_t Imm) {
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
unsigned ResultReg = createResultReg(RC);
Op0 = constrainOperandRegClass(II, Op0, II.getNumDefs());
Op1 = constrainOperandRegClass(II, Op1, II.getNumDefs() + 1);
if (II.getNumDefs() >= 1)
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)
@ -1371,9 +1407,12 @@ unsigned FastISel::FastEmitInst_rrii(unsigned MachineInstOpcode,
unsigned Op0, bool Op0IsKill,
unsigned Op1, bool Op1IsKill,
uint64_t Imm1, uint64_t Imm2) {
unsigned ResultReg = createResultReg(RC);
const MCInstrDesc &II = TII.get(MachineInstOpcode);
unsigned ResultReg = createResultReg(RC);
Op0 = constrainOperandRegClass(II, Op0, II.getNumDefs());
Op1 = constrainOperandRegClass(II, Op1, II.getNumDefs() + 1);
if (II.getNumDefs() >= 1)
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, II, ResultReg)
.addReg(Op0, Op0IsKill * RegState::Kill)

View File

@ -166,8 +166,6 @@ class ARMFastISel final : public FastISel {
// Utility routines.
private:
unsigned constrainOperandRegClass(const MCInstrDesc &II, unsigned OpNum,
unsigned Op);
bool isTypeLegal(Type *Ty, MVT &VT);
bool isLoadTypeLegal(Type *Ty, MVT &VT);
bool ARMEmitCmp(const Value *Src1Value, const Value *Src2Value,
@ -283,23 +281,6 @@ ARMFastISel::AddOptionalDefs(const MachineInstrBuilder &MIB) {
return MIB;
}
unsigned ARMFastISel::constrainOperandRegClass(const MCInstrDesc &II,
unsigned Op, unsigned OpNum) {
if (TargetRegisterInfo::isVirtualRegister(Op)) {
const TargetRegisterClass *RegClass =
TII.getRegClass(II, OpNum, &TRI, *FuncInfo.MF);
if (!MRI.constrainRegClass(Op, RegClass)) {
// If it's not legal to COPY between the register classes, something
// has gone very wrong before we got here.
unsigned NewOp = createResultReg(RegClass);
AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
TII.get(TargetOpcode::COPY), NewOp).addReg(Op));
return NewOp;
}
}
return Op;
}
unsigned ARMFastISel::FastEmitInst_r(unsigned MachineInstOpcode,
const TargetRegisterClass *RC,
unsigned Op0, bool Op0IsKill) {