diff options
Diffstat (limited to 'llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp')
| -rw-r--r-- | llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp b/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp index e3c0f95..872fe4b 100644 --- a/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp +++ b/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp @@ -191,6 +191,14 @@ static DecodeStatus decodeSImmOperand(MCInst &Inst, uint64_t Imm, return MCDisassembler::Success; } +static DecodeStatus decodeImmZeroOperand(MCInst &Inst, uint64_t Imm, + int64_t Address, const void *Decoder) { + if (Imm != 0) + return MCDisassembler::Fail; + Inst.addOperand(MCOperand::createImm(Imm)); + return MCDisassembler::Success; +} + static DecodeStatus decodeMemRIOperands(MCInst &Inst, uint64_t Imm, int64_t Address, const void *Decoder) { // Decode the memri field (imm, reg), which has the low 16-bits as the @@ -324,6 +332,29 @@ DecodeStatus PPCDisassembler::getInstruction(MCInst &MI, uint64_t &Size, ArrayRef<uint8_t> Bytes, uint64_t Address, raw_ostream &CS) const { + auto *ReadFunc = IsLittleEndian ? support::endian::read32le + : support::endian::read32be; + + // If this is an 8-byte prefixed instruction, handle it here. + // Note: prefixed instructions aren't technically 8-byte entities - the prefix + // appears in memory at an address 4 bytes prior to that of the base + // instruction regardless of endianness. So we read the two pieces and + // rebuild the 8-byte instruction. + // TODO: In this function we call decodeInstruction several times with + // different decoder tables. It may be possible to only call once by + // looking at the top 6 bits of the instruction. + if (STI.getFeatureBits()[PPC::FeaturePrefixInstrs] && Bytes.size() >= 8) { + uint32_t Prefix = ReadFunc(Bytes.data()); + uint32_t BaseInst = ReadFunc(Bytes.data() + 4); + uint64_t Inst = BaseInst | (uint64_t)Prefix << 32; + DecodeStatus result = decodeInstruction(DecoderTable64, MI, Inst, Address, + this, STI); + if (result != MCDisassembler::Fail) { + Size = 8; + return result; + } + } + // Get the four bytes of the instruction. Size = 4; if (Bytes.size() < 4) { @@ -332,8 +363,7 @@ DecodeStatus PPCDisassembler::getInstruction(MCInst &MI, uint64_t &Size, } // Read the instruction in the proper endianness. - uint32_t Inst = IsLittleEndian ? support::endian::read32le(Bytes.data()) - : support::endian::read32be(Bytes.data()); + uint64_t Inst = ReadFunc(Bytes.data()); if (STI.getFeatureBits()[PPC::FeatureQPX]) { DecodeStatus result = |