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, 3 insertions, 5 deletions

diff --git a/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp b/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp
index 101d1ca..5251b60 100644
--- a/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp
+++ b/llvm/lib/Target/PowerPC/Disassembler/PPCDisassembler.cpp
@@ -12,7 +12,6 @@
 #include "llvm/MC/MCFixedLenDisassembler.h"
 #include "llvm/MC/MCInst.h"
 #include "llvm/MC/MCSubtargetInfo.h"
-#include "llvm/Support/MemoryObject.h"
 #include "llvm/Support/TargetRegistry.h"
 
 using namespace llvm;
@@ -29,7 +28,7 @@ public:
   virtual ~PPCDisassembler() {}
 
   DecodeStatus getInstruction(MCInst &Instr, uint64_t &Size,
-                              const MemoryObject &Region, uint64_t Address,
+                              ArrayRef<uint8_t> Bytes, uint64_t Address,
                               raw_ostream &VStream,
                               raw_ostream &CStream) const override;
 };
@@ -322,13 +321,12 @@ static DecodeStatus decodeCRBitMOperand(MCInst &Inst, uint64_t Imm,
 #include "PPCGenDisassemblerTables.inc"
 
 DecodeStatus PPCDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
-                                             const MemoryObject &Region,
+                                             ArrayRef<uint8_t> Bytes,
                                              uint64_t Address, raw_ostream &OS,
                                              raw_ostream &CS) const {
   // Get the four bytes of the instruction.
-  uint8_t Bytes[4];
   Size = 4;
-  if (Region.readBytes(Address, Size, Bytes) == -1) {
+  if (Bytes.size() < 4) {
     Size = 0;
     return MCDisassembler::Fail;
   }