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>
This commit is contained in:
Claudio Fontana 2014-02-05 17:27:28 +00:00 committed by Peter Maydell
parent 37fd5b53ba
commit 999b53ec87
7 changed files with 118 additions and 3 deletions

4
configure vendored
View file

@ -4641,6 +4641,10 @@ for i in $ARCH $TARGET_BASE_ARCH ; do
arm)
echo "CONFIG_ARM_DIS=y" >> $config_target_mak
echo "CONFIG_ARM_DIS=y" >> config-all-disas.mak
if test -n "${cxx}"; then
echo "CONFIG_ARM_A64_DIS=y" >> $config_target_mak
echo "CONFIG_ARM_A64_DIS=y" >> config-all-disas.mak
fi
;;
cris)
echo "CONFIG_CRIS_DIS=y" >> $config_target_mak

14
disas.c
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@ -190,7 +190,7 @@ static int print_insn_od_target(bfd_vma pc, disassemble_info *info)
/* Disassemble this for me please... (debugging). 'flags' has the following
values:
i386 - 1 means 16 bit code, 2 means 64 bit code
arm - bit 0 = thumb, bit 1 = reverse endian
arm - bit 0 = thumb, bit 1 = reverse endian, bit 2 = A64
ppc - nonzero means little endian
other targets - unused
*/
@ -225,7 +225,15 @@ void target_disas(FILE *out, CPUArchState *env, target_ulong code,
}
print_insn = print_insn_i386;
#elif defined(TARGET_ARM)
if (flags & 1) {
if (flags & 4) {
/* We might not be compiled with the A64 disassembler
* because it needs a C++ compiler; in that case we will
* fall through to the default print_insn_od case.
*/
#if defined(CONFIG_ARM_A64_DIS)
print_insn = print_insn_arm_a64;
#endif
} else if (flags & 1) {
print_insn = print_insn_thumb1;
} else {
print_insn = print_insn_arm;
@ -356,6 +364,8 @@ 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__) && defined(CONFIG_ARM_A64_DIS)
print_insn = print_insn_arm_a64;
#elif defined(__alpha__)
print_insn = print_insn_alpha;
#elif defined(__sparc__)

View file

@ -1,5 +1,10 @@
common-obj-$(CONFIG_ALPHA_DIS) += alpha.o
common-obj-$(CONFIG_ARM_DIS) += arm.o
common-obj-$(CONFIG_ARM_A64_DIS) += arm-a64.o
common-obj-$(CONFIG_ARM_A64_DIS) += libvixl/
libvixldir = $(SRC_PATH)/disas/libvixl
$(obj)/arm-a64.o: QEMU_CFLAGS += -I$(libvixldir)
common-obj-$(CONFIG_CRIS_DIS) += cris.o
common-obj-$(CONFIG_HPPA_DIS) += hppa.o
common-obj-$(CONFIG_I386_DIS) += i386.o

87
disas/arm-a64.cc Normal file
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@ -0,0 +1,87 @@
/*
* 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;
}

View file

@ -0,0 +1,8 @@
libvixl_OBJS = utils.o \
a64/instructions-a64.o \
a64/decoder-a64.o \
a64/disasm-a64.o
$(addprefix $(obj)/,$(libvixl_OBJS)): QEMU_CFLAGS += -I$(SRC_PATH)/disas/libvixl
common-obj-$(CONFIG_ARM_A64_DIS) += $(libvixl_OBJS)

View file

@ -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_arm_a64 (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*);

View file

@ -8105,7 +8105,7 @@ done_generating:
qemu_log("----------------\n");
qemu_log("IN: %s\n", lookup_symbol(pc_start));
log_target_disas(env, pc_start, dc->pc - pc_start,
dc->thumb | (dc->bswap_code << 1));
4 | (dc->bswap_code << 1));
qemu_log("\n");
}
#endif