From 1144af3c9b4da48cd581156e05b24261c8de366a Mon Sep 17 00:00:00 2001 From: Richard Smith Date: Fri, 24 Aug 2012 23:29:28 +0000 Subject: Fix integer undefined behavior due to signed left shift overflow in LLVM. Reviewed offline by chandlerc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162623 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/ARM/Disassembler/ARMDisassembler.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib/Target/ARM/Disassembler/ARMDisassembler.cpp') diff --git a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp index c90751d..c394ed1 100644 --- a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp +++ b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp @@ -3170,7 +3170,7 @@ static DecodeStatus DecodeT2Imm8S4(MCInst &Inst, unsigned Val, int imm = Val & 0xFF; if (!(Val & 0x100)) imm *= -1; - Inst.addOperand(MCOperand::CreateImm(imm << 2)); + Inst.addOperand(MCOperand::CreateImm(imm * 4)); } return MCDisassembler::Success; -- cgit v1.1 From eae1d34029c159306ce4a0472294de6cf9baedac Mon Sep 17 00:00:00 2001 From: Tim Northover Date: Thu, 6 Sep 2012 15:17:49 +0000 Subject: Check for invalid alignment values when decoding VLDn/VSTn (single ln) instructions. Patch by Chris Lidbury. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163321 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/ARM/Disassembler/ARMDisassembler.cpp | 46 ++++++++++++++++++++----- 1 file changed, 38 insertions(+), 8 deletions(-) (limited to 'lib/Target/ARM/Disassembler/ARMDisassembler.cpp') diff --git a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp index c394ed1..657c103 100644 --- a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp +++ b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp @@ -3710,8 +3710,16 @@ static DecodeStatus DecodeVLD1LN(MCInst &Inst, unsigned Insn, if (fieldFromInstruction(Insn, 6, 1)) return MCDisassembler::Fail; // UNDEFINED index = fieldFromInstruction(Insn, 7, 1); - if (fieldFromInstruction(Insn, 4, 2) != 0) - align = 4; + + switch (fieldFromInstruction(Insn, 4, 2)) { + case 0 : + align = 0; break; + case 3: + align = 4; break; + default: + return MCDisassembler::Fail; + } + break; } if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder))) @@ -3769,8 +3777,16 @@ static DecodeStatus DecodeVST1LN(MCInst &Inst, unsigned Insn, if (fieldFromInstruction(Insn, 6, 1)) return MCDisassembler::Fail; // UNDEFINED index = fieldFromInstruction(Insn, 7, 1); - if (fieldFromInstruction(Insn, 4, 2) != 0) - align = 4; + + switch (fieldFromInstruction(Insn, 4, 2)) { + case 0: + align = 0; break; + case 3: + align = 4; break; + default: + return MCDisassembler::Fail; + } + break; } if (Rm != 0xF) { // Writeback @@ -4090,8 +4106,15 @@ static DecodeStatus DecodeVLD4LN(MCInst &Inst, unsigned Insn, inc = 2; break; case 2: - if (fieldFromInstruction(Insn, 4, 2)) - align = 4 << fieldFromInstruction(Insn, 4, 2); + switch (fieldFromInstruction(Insn, 4, 2)) { + case 0: + align = 0; break; + case 3: + return MCDisassembler::Fail; + default: + align = 4 << fieldFromInstruction(Insn, 4, 2); break; + } + index = fieldFromInstruction(Insn, 7, 1); if (fieldFromInstruction(Insn, 6, 1)) inc = 2; @@ -4164,8 +4187,15 @@ static DecodeStatus DecodeVST4LN(MCInst &Inst, unsigned Insn, inc = 2; break; case 2: - if (fieldFromInstruction(Insn, 4, 2)) - align = 4 << fieldFromInstruction(Insn, 4, 2); + switch (fieldFromInstruction(Insn, 4, 2)) { + case 0: + align = 0; break; + case 3: + return MCDisassembler::Fail; + default: + align = 4 << fieldFromInstruction(Insn, 4, 2); break; + } + index = fieldFromInstruction(Insn, 7, 1); if (fieldFromInstruction(Insn, 6, 1)) inc = 2; -- cgit v1.1 From 24b9f258f194c5e472bf133f9bbf5ca26ad500d3 Mon Sep 17 00:00:00 2001 From: Tim Northover Date: Thu, 6 Sep 2012 15:27:12 +0000 Subject: Diagnose invalid alignments on duplicating VLDn instructions. Patch by Chris Lidbury. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163323 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Target/ARM/Disassembler/ARMDisassembler.cpp | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'lib/Target/ARM/Disassembler/ARMDisassembler.cpp') diff --git a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp index 657c103..57642e1 100644 --- a/lib/Target/ARM/Disassembler/ARMDisassembler.cpp +++ b/lib/Target/ARM/Disassembler/ARMDisassembler.cpp @@ -2701,6 +2701,8 @@ static DecodeStatus DecodeVLD1DupInstruction(MCInst &Inst, unsigned Insn, unsigned align = fieldFromInstruction(Insn, 4, 1); unsigned size = fieldFromInstruction(Insn, 6, 2); + if (size == 0 && align == 1) + return MCDisassembler::Fail; align *= (1 << size); switch (Inst.getOpcode()) { @@ -2831,6 +2833,8 @@ static DecodeStatus DecodeVLD4DupInstruction(MCInst &Inst, unsigned Insn, unsigned align = fieldFromInstruction(Insn, 4, 1); if (size == 0x3) { + if (align == 0) + return MCDisassembler::Fail; size = 4; align = 16; } else { -- cgit v1.1