Add instruction encodings / disassembly support for l2r instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170345 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 70 insertions, 4 deletions

diff --git a/lib/Target/XCore/Disassembler/XCoreDisassembler.cpp b/lib/Target/XCore/Disassembler/XCoreDisassembler.cpp
index 4f60724f65..094f18ceee 100644
--- a/lib/Target/XCore/Disassembler/XCoreDisassembler.cpp
+++ b/lib/Target/XCore/Disassembler/XCoreDisassembler.cpp
@@ -62,6 +62,23 @@ static bool readInstruction16(const MemoryObject &region,
   return true;
 }
 
+static bool readInstruction32(const MemoryObject &region,
+                              uint64_t address,
+                              uint64_t &size,
+                              uint32_t &insn) {
+  uint8_t Bytes[4];
+
+  // We want to read exactly 4 Bytes of data.
+  if (region.readBytes(address, 4, Bytes, NULL) == -1) {
+    size = 0;
+    return false;
+  }
+  // Encoded as a little-endian 32-bit word in the stream.
+  insn = (Bytes[0] << 0) | (Bytes[1] << 8) | (Bytes[2] << 16) |
+         (Bytes[3] << 24);
+  return true;
+}
+
 static unsigned getReg(const void *D, unsigned RC, unsigned RegNo) {
   const XCoreDisassembler *Dis = static_cast<const XCoreDisassembler*>(D);
   return *(Dis->getRegInfo()->getRegClass(RC).begin() + RegNo);
@@ -105,6 +122,16 @@ static DecodeStatus DecodeRUSSrcDstBitpInstruction(MCInst &Inst,
                                                    uint64_t Address,
                                                    const void *Decoder);
 
+static DecodeStatus DecodeL2RInstruction(MCInst &Inst,
+                                         unsigned Insn,
+                                         uint64_t Address,
+                                         const void *Decoder);
+
+static DecodeStatus DecodeLR2RInstruction(MCInst &Inst,
+                                          unsigned Insn,
+                                          uint64_t Address,
+                                          const void *Decoder);
+
 #include "XCoreGenDisassemblerTables.inc"
 
 static DecodeStatus DecodeGRRegsRegisterClass(MCInst &Inst,
@@ -218,6 +245,32 @@ DecodeRUSSrcDstBitpInstruction(MCInst &Inst, unsigned Insn, uint64_t Address,
   return S;
 }
 
+static DecodeStatus
+DecodeL2RInstruction(MCInst &Inst, unsigned Insn, uint64_t Address,
+                               const void *Decoder) {
+  unsigned Op1, Op2;
+  DecodeStatus S = Decode2OpInstruction(fieldFromInstruction(Insn, 0, 16),
+                                        Op1, Op2);
+  if (S == MCDisassembler::Success) {
+    DecodeGRRegsRegisterClass(Inst, Op1, Address, Decoder);
+    DecodeGRRegsRegisterClass(Inst, Op2, Address, Decoder);
+  }
+  return S;
+}
+
+static DecodeStatus
+DecodeLR2RInstruction(MCInst &Inst, unsigned Insn, uint64_t Address,
+                               const void *Decoder) {
+  unsigned Op1, Op2;
+  DecodeStatus S = Decode2OpInstruction(fieldFromInstruction(Insn, 0, 16),
+                                        Op1, Op2);
+  if (S == MCDisassembler::Success) {
+    DecodeGRRegsRegisterClass(Inst, Op2, Address, Decoder);
+    DecodeGRRegsRegisterClass(Inst, Op1, Address, Decoder);
+  }
+  return S;
+}
+
 MCDisassembler::DecodeStatus
 XCoreDisassembler::getInstruction(MCInst &instr,
                                   uint64_t &Size,
@@ -225,20 +278,33 @@ XCoreDisassembler::getInstruction(MCInst &instr,
                                   uint64_t Address,
                                   raw_ostream &vStream,
                                   raw_ostream &cStream) const {
-  uint16_t low;
+  uint16_t insn16;
 
-  if (!readInstruction16(Region, Address, Size, low)) {
+  if (!readInstruction16(Region, Address, Size, insn16)) {
     return Fail;
   }
 
   // Calling the auto-generated decoder function.
-  DecodeStatus Result = decodeInstruction(DecoderTable16, instr, low, Address,
-                             this, STI);
+  DecodeStatus Result = decodeInstruction(DecoderTable16, instr, insn16,
+                                          Address, this, STI);
   if (Result != Fail) {
     Size = 2;
     return Result;
   }
 
+  uint32_t insn32;
+
+  if (!readInstruction32(Region, Address, Size, insn32)) {
+    return Fail;
+  }
+
+  // Calling the auto-generated decoder function.
+  Result = decodeInstruction(DecoderTable32, instr, insn32, Address, this, STI);
+  if (Result != Fail) {
+    Size = 4;
+    return Result;
+  }
+
   return Fail;
 }