From 68bcd021fd4240395088fcea4886d0f5f2f31fc0 Mon Sep 17 00:00:00 2001 From: Amaury de la Vieuville Date: Sat, 8 Jun 2013 13:43:59 +0000 Subject: ARM: enforce SRS decoding constraints llvm-svn: 183611 --- llvm/lib/Target/ARM/Disassembler/ARMDisassembler.cpp | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'llvm/lib/Target/ARM/Disassembler/ARMDisassembler.cpp') diff --git a/llvm/lib/Target/ARM/Disassembler/ARMDisassembler.cpp b/llvm/lib/Target/ARM/Disassembler/ARMDisassembler.cpp index bb0fc9b371e..08853cb3bb5 100644 --- a/llvm/lib/Target/ARM/Disassembler/ARMDisassembler.cpp +++ b/llvm/lib/Target/ARM/Disassembler/ARMDisassembler.cpp @@ -1768,6 +1768,7 @@ static DecodeStatus DecodeMemMultipleWritebackInstruction(MCInst &Inst, unsigned reglist = fieldFromInstruction(Insn, 0, 16); if (pred == 0xF) { + // Ambiguous with RFE and SRS switch (Inst.getOpcode()) { case ARM::LDMDA: Inst.setOpcode(ARM::RFEDA); @@ -1818,11 +1819,16 @@ static DecodeStatus DecodeMemMultipleWritebackInstruction(MCInst &Inst, Inst.setOpcode(ARM::SRSIB_UPD); break; default: - if (!Check(S, MCDisassembler::Fail)) return MCDisassembler::Fail; + return MCDisassembler::Fail; } // For stores (which become SRS's, the only operand is the mode. if (fieldFromInstruction(Insn, 20, 1) == 0) { + // Check SRS encoding constraints + if (!(fieldFromInstruction(Insn, 22, 1) == 1 && + fieldFromInstruction(Insn, 20, 1) == 0)) + return MCDisassembler::Fail; + Inst.addOperand( MCOperand::CreateImm(fieldFromInstruction(Insn, 0, 4))); return S; -- cgit v1.2.3