Fix a LDRT/LDRBT decoding bug where for Encoding A2, if Inst{4} != 0, we should reject the instruction

as invalid.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128734 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Johnny Chen
2011-04-01 20:21:38 +00:00
parent ce1498bdbe
commit ec30f6f5e5
3 changed files with 23 additions and 0 deletions

View File

@@ -1106,6 +1106,14 @@ static bool DisassembleLdStFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
MI.addOperand(MCOperand::CreateImm(Offset));
OpIdx += 1;
} else {
// The opcode ARM::LDRT actually corresponds to both Encoding A1 and A2 of
// A8.6.86 LDRT. So if Inst{4} != 0 while Inst{25} (getIBit(insn)) == 1,
// we should reject this insn as invalid.
//
// Ditto for LDRBT.
if ((Opcode == ARM::LDRT || Opcode == ARM::LDRBT) && (slice(insn,4,4) == 1))
return false;
// Disassemble the offset reg (Rm), shift type, and immediate shift length.
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));