[riscv] Consolidate logic for SEW/VL operand offset calculations [nfc]

This commit is contained in:
Philip Reames 2022-05-10 15:06:26 -07:00
parent 413052310a
commit 7731935ffc

View file

@ -542,11 +542,29 @@ static bool isScalarMoveInstr(const MachineInstr &MI) {
}
}
static unsigned getVLOpNum(const MachineInstr &MI) {
const uint64_t TSFlags = MI.getDesc().TSFlags;
// This method is only called if we expect to have a VL operand, and all
// instructions with VL also have SEW.
assert(RISCVII::hasSEWOp(TSFlags) && RISCVII::hasVLOp(TSFlags));
unsigned Offset = 2;
if (RISCVII::hasVecPolicyOp(TSFlags))
Offset = 3;
return MI.getNumExplicitOperands() - Offset;
}
static unsigned getSEWOpNum(const MachineInstr &MI) {
const uint64_t TSFlags = MI.getDesc().TSFlags;
assert(RISCVII::hasSEWOp(TSFlags));
unsigned Offset = 1;
if (RISCVII::hasVecPolicyOp(TSFlags))
Offset = 2;
return MI.getNumExplicitOperands() - Offset;
}
static VSETVLIInfo computeInfoForInstr(const MachineInstr &MI, uint64_t TSFlags,
const MachineRegisterInfo *MRI) {
VSETVLIInfo InstrInfo;
unsigned NumOperands = MI.getNumExplicitOperands();
bool HasPolicy = RISCVII::hasVecPolicyOp(TSFlags);
// If the instruction has policy argument, use the argument.
// If there is no policy argument, default to tail agnostic unless the
@ -561,7 +579,7 @@ static VSETVLIInfo computeInfoForInstr(const MachineInstr &MI, uint64_t TSFlags,
// vsetvli between mask and nomasked instruction sequence.
bool MaskAgnostic = UsesMaskPolicy;
unsigned UseOpIdx;
if (HasPolicy) {
if (RISCVII::hasVecPolicyOp(TSFlags)) {
const MachineOperand &Op = MI.getOperand(MI.getNumExplicitOperands() - 1);
uint64_t Policy = Op.getImm();
assert(Policy <= (RISCVII::TAIL_AGNOSTIC | RISCVII::MASK_AGNOSTIC) &&
@ -593,13 +611,9 @@ static VSETVLIInfo computeInfoForInstr(const MachineInstr &MI, uint64_t TSFlags,
TailAgnostic = true;
}
// Remove the tail policy so we can find the SEW and VL.
if (HasPolicy)
--NumOperands;
RISCVII::VLMUL VLMul = RISCVII::getLMul(TSFlags);
unsigned Log2SEW = MI.getOperand(NumOperands - 1).getImm();
unsigned Log2SEW = MI.getOperand(getSEWOpNum(MI)).getImm();
// A Log2SEW of 0 is an operation on mask registers only.
bool MaskRegOp = Log2SEW == 0;
unsigned SEW = Log2SEW ? 1 << Log2SEW : 8;
@ -611,7 +625,7 @@ static VSETVLIInfo computeInfoForInstr(const MachineInstr &MI, uint64_t TSFlags,
bool ScalarMovOp = isScalarMoveInstr(MI);
if (RISCVII::hasVLOp(TSFlags)) {
const MachineOperand &VLOp = MI.getOperand(NumOperands - 2);
const MachineOperand &VLOp = MI.getOperand(getVLOpNum(MI));
if (VLOp.isImm()) {
int64_t Imm = VLOp.getImm();
// Conver the VLMax sentintel to X0 register.
@ -1103,11 +1117,7 @@ void RISCVInsertVSETVLI::emitVSETVLIs(MachineBasicBlock &MBB) {
if (RISCVII::hasSEWOp(TSFlags)) {
VSETVLIInfo NewInfo = computeInfoForInstr(MI, TSFlags, MRI);
if (RISCVII::hasVLOp(TSFlags)) {
unsigned Offset = 2;
if (RISCVII::hasVecPolicyOp(TSFlags))
Offset = 3;
MachineOperand &VLOp =
MI.getOperand(MI.getNumExplicitOperands() - Offset);
MachineOperand &VLOp = MI.getOperand(getVLOpNum(MI));
if (VLOp.isReg()) {
// Erase the AVL operand from the instruction.
VLOp.setReg(RISCV::NoRegister);