From cb775519279cd1471c490eb5bf4e3ce663fcdc7d Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Fri, 16 Sep 2011 23:30:01 +0000 Subject: [PATCH] Bitfield mask instructions are unpredictable if the encoded LSB is higher than the encoded MSB. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139972 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/ARM/Disassembler/ARMDisassembler.cpp | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp index 4e9c3e58a5f..d76fb93d156 100644 --- a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp +++ b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp @@ -1004,12 +1004,15 @@ static DecodeStatus DecodeBitfieldMaskOperand(llvm::MCInst &Inst, unsigned Val, unsigned msb = fieldFromInstruction32(Val, 5, 5); unsigned lsb = fieldFromInstruction32(Val, 0, 5); + DecodeStatus S = MCDisassembler::Success; + if (lsb > msb) Check(S, MCDisassembler::SoftFail); + uint32_t msb_mask = 0xFFFFFFFF; if (msb != 31) msb_mask = (1U << (msb+1)) - 1; uint32_t lsb_mask = (1U << lsb) - 1; Inst.addOperand(MCOperand::CreateImm(~(msb_mask ^ lsb_mask))); - return MCDisassembler::Success; + return S; } static DecodeStatus DecodeCopMemInstruction(llvm::MCInst &Inst, unsigned Insn, -- 2.34.1