qemu/disas/arm-a64.cc
Claudio Fontana 999b53ec87 disas: Implement disassembly output for A64
Use libvixl to implement disassembly output in debug
logs for A64, for use with both AArch64 hosts and targets.

Signed-off-by: Claudio Fontana <claudio.fontana@linaro.org>
[PMM:
 * added support for target disassembly
 * switched to custom QEMUDisassembler so the output format
   matches what QEMU expects
 * make sure we correctly fall back to "just print hex"
   if we didn't build the AArch64 disassembler because of
   lack of a C++ compiler
 * rename from 'aarch64' to 'arm-a64' because this is a
   disassembler for the A64 instruction set
 * merge aarch64.c and aarch64-cxx.cc into one C++ file
 * simplify the aarch64.c<->aarch64-cxx.cc interface]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-08 14:50:48 +00:00

88 lines
2.3 KiB
C++

/*
* ARM A64 disassembly output wrapper to libvixl
* Copyright (c) 2013 Linaro Limited
* Written by Claudio Fontana
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "a64/disasm-a64.h"
extern "C" {
#include "disas/bfd.h"
}
using namespace vixl;
static Decoder *vixl_decoder = NULL;
static Disassembler *vixl_disasm = NULL;
/* We don't use libvixl's PrintDisassembler because its output
* is a little unhelpful (trailing newlines, for example).
* Instead we use our own very similar variant so we have
* control over the format.
*/
class QEMUDisassembler : public Disassembler {
public:
explicit QEMUDisassembler(FILE *stream) : stream_(stream) { }
~QEMUDisassembler() { }
protected:
void ProcessOutput(Instruction *instr) {
fprintf(stream_, "%08" PRIx32 " %s",
instr->InstructionBits(), GetOutput());
}
private:
FILE *stream_;
};
static int vixl_is_initialized(void)
{
return vixl_decoder != NULL;
}
static void vixl_init(FILE *f) {
vixl_decoder = new Decoder();
vixl_disasm = new QEMUDisassembler(f);
vixl_decoder->AppendVisitor(vixl_disasm);
}
#define INSN_SIZE 4
/* Disassemble ARM A64 instruction. This is our only entry
* point from QEMU's C code.
*/
int print_insn_arm_a64(uint64_t addr, disassemble_info *info)
{
uint8_t bytes[INSN_SIZE];
uint32_t instr;
int status;
status = info->read_memory_func(addr, bytes, INSN_SIZE, info);
if (status != 0) {
info->memory_error_func(status, addr, info);
return -1;
}
if (!vixl_is_initialized()) {
vixl_init(info->stream);
}
instr = bytes[0] | bytes[1] << 8 | bytes[2] << 16 | bytes[3] << 24;
vixl_decoder->Decode(reinterpret_cast<Instruction*>(&instr));
return INSN_SIZE;
}