[Qemu-devel] [RFC 4/4] disas: implement host disassembly output for aarch64

[Claudio Fontana <claudio.fontana@huawei.com>]

use C++ libvixl to implement output, for now only enabled for the host output
disasm, since we don't have the aarch64 target yet.

Signed-off-by: Claudio Fontana <claudio.fontana@linaro.org>
---
 configure                   |  6 +++++
 disas.c                     |  2 ++
 disas/Makefile.objs         |  7 ++++++
 disas/aarch64-cxx.cc        | 53 +++++++++++++++++++++++++++++++++++++++++++++
 disas/aarch64.c             | 45 ++++++++++++++++++++++++++++++++++++++
 disas/libvixl/Makefile.objs |  6 +++++
 include/disas/bfd.h         |  1 +
 7 files changed, 120 insertions(+)
 create mode 100644 disas/aarch64-cxx.cc
 create mode 100644 disas/aarch64.c
 create mode 100644 disas/libvixl/Makefile.objs

diff --git a/configure b/configure
index 6b73d99..1a2648a 100755
--- a/configure
+++ b/configure
@@ -4443,6 +4443,12 @@ ldflags=""
 
 for i in $ARCH $TARGET_BASE_ARCH ; do
   case "$i" in
+  aarch64)
+    if test "x${cxx}" != "x"; then
+      echo "CONFIG_AARCH64_DIS=y"  >> $config_target_mak
+      echo "CONFIG_AARCH64_DIS=y"  >> config-all-disas.mak
+    fi
+  ;;
   alpha)
     echo "CONFIG_ALPHA_DIS=y"  >> $config_target_mak
     echo "CONFIG_ALPHA_DIS=y"  >> config-all-disas.mak
diff --git a/disas.c b/disas.c
index 0203ef2..cc20c4a 100644
--- a/disas.c
+++ b/disas.c
@@ -356,6 +356,8 @@ void disas(FILE *out, void *code, unsigned long size)
 #elif defined(_ARCH_PPC)
     s.info.disassembler_options = (char *)"any";
     print_insn = print_insn_ppc;
+#elif defined(__aarch64__)
+    print_insn = print_insn_aarch64;
 #elif defined(__alpha__)
     print_insn = print_insn_alpha;
 #elif defined(__sparc__)
diff --git a/disas/Makefile.objs b/disas/Makefile.objs
index 3b1e77a..f468c22 100644
--- a/disas/Makefile.objs
+++ b/disas/Makefile.objs
@@ -1,3 +1,10 @@
+ifeq ($(CONFIG_AARCH64_DIS),y)
+libvixldir = $(SRC_PATH)/disas/libvixl/src
+QEMU_CFLAGS += -I$(libvixldir) -Wno-undef
+common-obj-$(CONFIG_AARCH64_DIS) += libvixl/
+common-obj-$(CONFIG_AARCH64_DIS) += aarch64.o aarch64-cxx.o
+endif
+
 common-obj-$(CONFIG_ALPHA_DIS) += alpha.o
 common-obj-$(CONFIG_ARM_DIS) += arm.o
 common-obj-$(CONFIG_CRIS_DIS) += cris.o
diff --git a/disas/aarch64-cxx.cc b/disas/aarch64-cxx.cc
new file mode 100644
index 0000000..524f5ae
--- /dev/null
+++ b/disas/aarch64-cxx.cc
@@ -0,0 +1,53 @@
+/*
+ * Aarch64 disassembly output wrapper to libvixl - C++ part
+ * 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/simulator-a64.h"
+#include "a64/macro-assembler-a64.h"
+
+extern "C" {
+    int vixl_is_initialized(int);
+    int vixl_init(FILE *f);
+    int vixl_decode_insn(uint8_t *bytes);
+}
+
+using namespace vixl;
+
+static Decoder *vixl_decoder = NULL;
+static Disassembler *vixl_disasm = NULL;
+
+int vixl_is_initialized(int unused)
+{
+    return vixl_decoder != NULL;
+}
+
+/* Disassemble Aarch64 bytecode - wrappers */
+int vixl_init(FILE *f) {
+    vixl_decoder = new Decoder();
+    vixl_disasm = new PrintDisassembler(f);
+    vixl_decoder->AppendVisitor(vixl_disasm);
+    return 1;
+}
+
+int vixl_decode_insn(uint8_t *bytes)
+{
+    Instr instr;
+    instr = bytes[0] | bytes[1] << 8 | bytes[2] << 16 | bytes[3] << 24;
+    vixl_decoder->Decode(reinterpret_cast<Instruction*>(&instr));
+    return 1;
+}
diff --git a/disas/aarch64.c b/disas/aarch64.c
new file mode 100644
index 0000000..7e44837
--- /dev/null
+++ b/disas/aarch64.c
@@ -0,0 +1,45 @@
+/*
+ * Aarch64 disassembly output wrapper to libvixl - C part
+ * 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 "disas/bfd.h"
+#define INSN_SIZE 4
+
+extern int vixl_is_initialized(int);
+extern int vixl_init(FILE *);
+extern int vixl_decode_insn(uint8_t *);
+
+/* Disassemble Aarch64 bytecode. */
+int print_insn_aarch64(uint64_t addr, disassemble_info *info)
+{
+    uint8_t bytes[INSN_SIZE];
+    int status;
+
+    if (!vixl_is_initialized(0)) {
+        vixl_init(info->stream);
+    }
+
+    status = info->read_memory_func(addr, bytes, INSN_SIZE, info);
+    if (status != 0) {
+        info->memory_error_func(status, addr, info);
+        return -1;
+    }
+
+    vixl_decode_insn(bytes);
+    return INSN_SIZE;
+}
diff --git a/disas/libvixl/Makefile.objs b/disas/libvixl/Makefile.objs
new file mode 100644
index 0000000..43ba29c
--- /dev/null
+++ b/disas/libvixl/Makefile.objs
@@ -0,0 +1,6 @@
+libvixl_OBJS = src/utils.o \
+               src/a64/instructions-a64.o \
+               src/a64/decoder-a64.o \
+               src/a64/disasm-a64.o
+
+common-obj-$(CONFIG_AARCH64_DIS) += $(libvixl_OBJS)
diff --git a/include/disas/bfd.h b/include/disas/bfd.h
index 803b6ef..73017da 100644
--- a/include/disas/bfd.h
+++ b/include/disas/bfd.h
@@ -379,6 +379,7 @@ int print_insn_h8300            (bfd_vma, disassemble_info*);
 int print_insn_h8300h           (bfd_vma, disassemble_info*);
 int print_insn_h8300s           (bfd_vma, disassemble_info*);
 int print_insn_h8500            (bfd_vma, disassemble_info*);
+int print_insn_aarch64          (bfd_vma, disassemble_info*);
 int print_insn_alpha            (bfd_vma, disassemble_info*);
 disassembler_ftype arc_get_disassembler (int, int);
 int print_insn_arm              (bfd_vma, disassemble_info*);
-- 
1.8.1