Pass an ArrayRef to MCDisassembler::getInstruction.

With this patch MCDisassembler::getInstruction takes an ArrayRef<uint8_t>
instead of a MemoryObject.

Even on X86 there is a maximum size an instruction can have. Given
that, it seems way simpler and more efficient to just pass an ArrayRef
to the disassembler instead of a MemoryObject and have it do a virtual
call every time it wants some extra bytes.

llvm-svn: 221751

1 files changed, 2 insertions, 3 deletions

diff --git a/llvm/tools/llvm-mc/Disassembler.cpp b/llvm/tools/llvm-mc/Disassembler.cpp
index a3f9191d50e..75124db9cd3 100644
--- a/llvm/tools/llvm-mc/Disassembler.cpp
+++ b/llvm/tools/llvm-mc/Disassembler.cpp
@@ -38,8 +38,7 @@ static bool PrintInsts(const MCDisassembler &DisAsm,
                        MCStreamer &Streamer, bool InAtomicBlock,
                        const MCSubtargetInfo &STI) {
   // Wrap the vector in a MemoryObject.
-  StringRef Data((const char*)Bytes.first.data(), Bytes.first.size());
-  StringRefMemoryObject memoryObject(Data);
+  ArrayRef<uint8_t> Data(Bytes.first.data(), Bytes.first.size());
 
   // Disassemble it to strings.
   uint64_t Size;
@@ -49,7 +48,7 @@ static bool PrintInsts(const MCDisassembler &DisAsm,
     MCInst Inst;
 
     MCDisassembler::DecodeStatus S;
-    S = DisAsm.getInstruction(Inst, Size, memoryObject, Index,
+    S = DisAsm.getInstruction(Inst, Size, Data.slice(Index), Index,
                               /*REMOVE*/ nulls(), nulls());
     switch (S) {
     case MCDisassembler::Fail: