MO & MI
C++
for (unsigned i = getDesc().getNumOperands(), e = getNumOperands(); i!= e; ++i)
MachineOperand &MO = getOperand(i);
for (unsigned i = Desc.getNumOperands(), e = OldMI.getNumOperands();
for (const MachineOperand &MO : MI->operands())
for (const MachineOperand &MO : MI.implicit_operands())
for (MachineOperand &MO : MI.explicit_operands())
for (MachineOperand &MO : reverse(MI.explicit_uses()))
for (const MachineOperand &MO : MI->defs())
for (MachineOperand &MO : MI.uses())
for (const MachineBasicBlock &MBB : MF)
for (const MachineBasicBlock *Succ : MBB->successors())
for (const MachineBasicBlock *Pred : MBB->predecessors())
MachineFunction::const_iterator MBBI = std::next(MBB->getIterator());
llvm/llvm/lib/CodeGen/LiveVariables.cpp
llvm-lit -a ~/llvm/llvm/test/CodeGen/PowerPC/test_call_aix.ll
C++
if (MO.isRegMask()) {
MI.dump();
// BL_NOP <mcsymbol .foo>, <regmask $cr2 $cr3 $cr4 $f14 $f15 $f16 $f17 $f18 $f19 $f20 $f21 $f22 $f23 $f24 $f25 $f26 $f27 $f28 $f29 $f30 $f31 $r13 $r14 $r15 $r16 $r17 $r18 $r19 $r20 $r21 $r22 $r23 $r24 and 19 more...>, implicit-def dead $lr, implicit $rm, implicit $r2, implicit-def $r1
dbgs() << "MI.Desc().getNumOperands: " << MI.getDesc().getNumOperands() << "\n";
// MI.Desc().getNumOperands: 1
dbgs() << "MI.getNumOperands: " << MI.getNumOperands() << "\n";
// MI.getNumOperands: 6
for (const MachineOperand &MO : MI.operands())
MO.dump();
// <mcsymbol .foo>
// <regmask $cr2 $cr3 $cr4 $f14 $f15 $f16 $f17 $f18 $f19 $f20 $f21 $f22 $f23 $f24 $f25 $f26 $f27 $f28 $f29 $f30 $f31 $r13 $r14 $r15 $r16 $r17 $r18 $r19 $r20 $r21 $r22 $r23 $r24 and 19 more...>
// implicit-def dead $lr
// implicit $rm
// implicit $r2
// implicit-def $r1
for (const MachineOperand &MO : MI.implicit_operands())
MO.dump();
// <regmask $cr2 $cr3 $cr4 $f14 $f15 $f16 $f17 $f18 $f19 $f20 $f21 $f22 $f23 $f24 $f25 $f26 $f27 $f28 $f29 $f30 $f31 $r13 $r14 $r15 $r16 $r17 $r18 $r19 $r20 $r21 $r22 $r23 $r24 and 19 more...>
// implicit-def dead $lr
// implicit $rm
// implicit $r2
// implicit-def $r1
for (const MachineOperand &MO : MI.explicit_operands())
MO.dump();
// <mcsymbol .foo>
MO.dump();
// <regmask $cr2 $cr3 $cr4 $f14 $f15 $f16 $f17 $f18 $f19 $f20 $f21 $f22 $f23 $f24 $f25 $f26 $f27 $f28 $f29 $f30 $f31 $r13 $r14 $r15 $r16 $r17 $r18 $r19 $r20 $r21 $r22 $r23 $r24 and 19 more...>
assert(false);
RegMasks.push_back(i);
continue;
}
Text Only
MI.getDesc().getNumOperands() 不包括implicit OP,只有explicit op
MI.getNumOperands() 包括所有的op
implicit包括regMask
Regmask是在CALL指令上用的，比如：
regmask表示foo函数会用哪些reg，基本上是一些CSR reg。