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
diff --git a/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp b/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp
index 0e81302..8bc4ca9 100644
--- a/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp
+++ b/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp
@@ -16,7 +16,6 @@
#include "SparcSubtarget.h"
#include "llvm/MC/MCDisassembler.h"
#include "llvm/MC/MCFixedLenDisassembler.h"
-#include "llvm/Support/MemoryObject.h"
#include "llvm/Support/TargetRegistry.h"
using namespace llvm;
@@ -35,7 +34,7 @@
virtual ~SparcDisassembler() {}
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;
};
@@ -207,14 +206,11 @@
#include "SparcGenDisassemblerTables.inc"
-/// Read four bytes from the MemoryObject and return 32 bit word.
-static DecodeStatus readInstruction32(const MemoryObject &Region,
- uint64_t Address, uint64_t &Size,
- uint32_t &Insn) {
- uint8_t Bytes[4];
-
+/// Read four bytes from the ArrayRef and return 32 bit word.
+static DecodeStatus readInstruction32(ArrayRef<uint8_t> Bytes, uint64_t Address,
+ uint64_t &Size, uint32_t &Insn) {
// We want to read exactly 4 Bytes of data.
- if (Region.readBytes(Address, 4, Bytes) == -1) {
+ if (Bytes.size() < 4) {
Size = 0;
return MCDisassembler::Fail;
}
@@ -227,13 +223,13 @@
}
DecodeStatus SparcDisassembler::getInstruction(MCInst &Instr, uint64_t &Size,
- const MemoryObject &Region,
+ ArrayRef<uint8_t> Bytes,
uint64_t Address,
raw_ostream &VStream,
raw_ostream &CStream) const {
uint32_t Insn;
- DecodeStatus Result = readInstruction32(Region, Address, Size, Insn);
+ DecodeStatus Result = readInstruction32(Bytes, Address, Size, Insn);
if (Result == MCDisassembler::Fail)
return MCDisassembler::Fail;