1 //===------ llvm/MC/MCInstrDesc.cpp- Instruction Descriptors --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines methods on the MCOperandInfo and MCInstrDesc classes, which
10 // are used to describe target instructions and their operands.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "llvm/MC/MCInstrDesc.h"
15 #include "llvm/MC/MCInst.h"
16 #include "llvm/MC/MCRegisterInfo.h"
17 #include "llvm/MC/MCSubtargetInfo.h"
18
19 using namespace llvm;
20
mayAffectControlFlow(const MCInst & MI,const MCRegisterInfo & RI) const21 bool MCInstrDesc::mayAffectControlFlow(const MCInst &MI,
22 const MCRegisterInfo &RI) const {
23 if (isBranch() || isCall() || isReturn() || isIndirectBranch())
24 return true;
25 unsigned PC = RI.getProgramCounter();
26 if (PC == 0)
27 return false;
28 if (hasDefOfPhysReg(MI, PC, RI))
29 return true;
30 return false;
31 }
32
hasImplicitDefOfPhysReg(unsigned Reg,const MCRegisterInfo * MRI) const33 bool MCInstrDesc::hasImplicitDefOfPhysReg(unsigned Reg,
34 const MCRegisterInfo *MRI) const {
35 if (const MCPhysReg *ImpDefs = ImplicitDefs)
36 for (; *ImpDefs; ++ImpDefs)
37 if (*ImpDefs == Reg || (MRI && MRI->isSubRegister(Reg, *ImpDefs)))
38 return true;
39 return false;
40 }
41
hasDefOfPhysReg(const MCInst & MI,unsigned Reg,const MCRegisterInfo & RI) const42 bool MCInstrDesc::hasDefOfPhysReg(const MCInst &MI, unsigned Reg,
43 const MCRegisterInfo &RI) const {
44 for (int i = 0, e = NumDefs; i != e; ++i)
45 if (MI.getOperand(i).isReg() &&
46 RI.isSubRegisterEq(Reg, MI.getOperand(i).getReg()))
47 return true;
48 if (variadicOpsAreDefs())
49 for (int i = NumOperands - 1, e = MI.getNumOperands(); i != e; ++i)
50 if (MI.getOperand(i).isReg() &&
51 RI.isSubRegisterEq(Reg, MI.getOperand(i).getReg()))
52 return true;
53 return hasImplicitDefOfPhysReg(Reg, &RI);
54 }
55