Re: [PATCH v37 10/17] target/avr: Add instruction disassembly function

On Mon, Dec 2, 2019 at 2:28 AM Aleksandar Markovic <address@hidden> wrote:

On Wednesday, November 27, 2019, Michael Rolnik <address@hidden> wrote:
Provide function disassembles executed instruction when `-d in_asm` is
provided

Example:
`./avr-softmmu/qemu-system-avr -bios free-rtos/Demo/AVR_ATMega2560_GCC/demo.elf -d in_asm` will produce something like the following

```
...
IN:
0x0000014a: CALL 0x3808

IN: main
0x00003808: CALL 0x4b4

IN: vParTestInitialise
0x000004b4: LDI r24, 255
0x000004b6: STS r24, 0
0x000004b8: MULS r16, r20
0x000004ba: OUT $1, r24
0x000004bc: LDS r24, 0
0x000004be: MULS r16, r20
0x000004c0: OUT $2, r24
0x000004c2: RET
...
```

Signed-off-by: Michael Rolnik <address@hidden>
Suggested-by: Richard Henderson <address@hidden>
Suggested-by: Philippe Mathieu-Daudé <address@hidden>
Suggested-by: Aleksandar Markovic <address@hidden>
Reviewed-by: Philippe Mathieu-Daudé <address@hidden>
Tested-by: Philippe Mathieu-Daudé <address@hidden>
---
target/avr/cpu.h | 1 +
target/avr/cpu.c | 2 +-
target/avr/disas.c | 228 +++++++++++++++++++++++++++++++++++++++++
target/avr/translate.c | 11 ++
4 files changed, 241 insertions(+), 1 deletion(-)
create mode 100644 target/avr/disas.c

diff --git a/target/avr/cpu.h b/target/avr/cpu.h
index 9ea5260165..a3e615a1eb 100644
--- a/target/avr/cpu.h
+++ b/target/avr/cpu.h
@@ -157,6 +157,7 @@ bool avr_cpu_exec_interrupt(CPUState *cpu, int int_req);
hwaddr avr_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
int avr_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
int avr_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
+int avr_print_insn(bfd_vma addr, disassemble_info *info);

static inline int avr_feature(CPUAVRState *env, int feature)
{
diff --git a/target/avr/cpu.c b/target/avr/cpu.c
index dae56d7845..52ec21dd16 100644
--- a/target/avr/cpu.c
+++ b/target/avr/cpu.c
@@ -83,7 +83,7 @@ static void avr_cpu_reset(CPUState *cs)
static void avr_cpu_disas_set_info(CPUState *cpu, disassemble_info *info)
{
info->mach = bfd_arch_avr;
- info->print_insn = NULL;
+ info->print_insn = avr_print_insn;
}

static void avr_cpu_realizefn(DeviceState *dev, Error **errp)
diff --git a/target/avr/disas.c b/target/avr/disas.c
new file mode 100644
index 0000000000..a51ade7c2a
--- /dev/null
+++ b/target/avr/disas.c
@@ -0,0 +1,228 @@
+/*
+ * AVR disassembler
+ *
+ * Copyright (c) 2018 Richard Henderson <address@hidden>

Just a detail: since this file is created in 2019, the copyright year should be 2019 too.

+ * Copyright (c) 2019 Michael Rolnik <address@hidden>
+ *
+ * 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 "qemu/osdep.h"
+#include "disas/dis-asm.h"
+#include "qemu/bitops.h"
+#include "cpu.h"
+
+typedef struct {
+ disassemble_info *info;
+ uint16_t next_word;
+ bool next_word_used;
+} DisasContext;
+
+static int to_regs_16_31_by_one(DisasContext *ctx, int indx)
+{
+ return 16 + (indx % 16);
+}
+
+static int to_regs_16_23_by_one(DisasContext *ctx, int indx)
+{
+ return 16 + (indx % 8);
+}
+static int to_regs_24_30_by_two(DisasContext *ctx, int indx)
+{
+ return 24 + (indx % 4) * 2;
+}
+static int to_regs_00_30_by_two(DisasContext *ctx, int indx)
+{
+ return (indx % 16) * 2;
+}
+
+static uint16_t next_word(DisasContext *ctx)
+{
+ ctx->next_word_used = true;
+ return ctx->next_word;
+}
+
+static int append_16(DisasContext *ctx, int x)
+{
+ return x << 16 | next_word(ctx);
+}
+
+
+/* Include the auto-generated decoder. */
+static bool decode_insn(DisasContext *ctx, uint16_t insn);
+#include "decode_insn.inc.c"
+
+#define output(mnemonic, format, ...) \
+ (pctx->info->fprintf_func(pctx->info->stream, "%-9s " format, \
+ mnemonic, ##__VA_ARGS__))
+
+int avr_print_insn(bfd_vma addr, disassemble_info *info)
+{
+ DisasContext ctx;
+ DisasContext *pctx = &ctx;
+ bfd_byte buffer[4];
+ uint16_t insn;
+ int status;
+
+ ctx.info = info;
+
+ status = info->read_memory_func(addr, buffer, 4, info);
+ if (status != 0) {
+ info->memory_error_func(status, addr, info);
+ return -1;
+ }
+ insn = bfd_getl16(buffer);
+ ctx.next_word = bfd_getl16(buffer + 2);
+ ctx.next_word_used = false;
+
+ if (!decode_insn(&ctx, insn)) {
+ output(".db", "0x%02x, 0x%02x", buffer[0], buffer[1]);
+ }
+
+ return ctx.next_word_used ? 4 : 2;
+}
+
+
+#define INSN(opcode, format, ...) \
+static bool trans_##opcode(DisasContext *pctx, arg_##opcode * a) \
+{ \
+ output(#opcode, format, ##__VA_ARGS__); \
+ return true; \
+}
+
+#define INSN_MNEMONIC(opcode, mnemonic, format, ...) \
+static bool trans_##opcode(DisasContext *pctx, arg_##opcode * a) \
+{ \
+ output(mnemonic, format, ##__VA_ARGS__); \
+ return true; \
+}
+
+/*
+ * C Z N V S H T I
+ * 0 1 2 3 4 5 6 7
+ */
+static const char *brbc[] = {
+ "BRCC", "BRNE", "BRPL", "BRVC", "BRGE", "BRHC", "BRTC", "BRID"
+};
+
+static const char *brbs[] = {
+ "BRCS", "BREQ", "BRMI", "BRVS", "BRLT", "BRHS", "BRTS", "BRIE"
+};
+
+static const char *bset[] = {
+ "SEC", "SEZ", "SEN", "SEZ", "SES", "SEH", "SET", "SEI"
+};
+
+static const char *bclr[] = {
+ "CLC", "CLZ", "CLN", "CLZ", "CLS", "CLH", "CLT", "CLI"
+};
+
+INSN(ADC, "r%d, r%d", a->rd, a->rr)
+INSN(ADD, "r%d, r%d", a->rd, a->rr)
+INSN(ADIW, "r%d:r%d, %d", a->rd + 1, a->rd, a->imm)
+INSN(AND, "r%d, r%d", a->rd, a->rr)
+INSN(ANDI, "r%d, %d", a->rd, a->imm)
+INSN(ASR, "r%d", a->rd)
+INSN_MNEMONIC(BCLR, bclr[a->bit], "")
+INSN(BLD, "r%d, %d", a->rd, a->bit)
+INSN_MNEMONIC(BRBC, brbc[a->bit], ".%+d", a->imm * 2)
+INSN_MNEMONIC(BRBS, brbs[a->bit], ".%+d", a->imm * 2)
+INSN(BREAK, "")
+INSN_MNEMONIC(BSET, bset[a->bit], "")
+INSN(BST, "r%d, %d", a->rd, a->bit)
+INSN(CALL, "0x%x", a->imm * 2)
+INSN(CBI, "%d, %d", a->reg, a->bit)
+INSN(COM, "r%d", a->rd)
+INSN(CP, "r%d, r%d", a->rd, a->rr)
+INSN(CPC, "r%d, r%d", a->rd, a->rr)
+INSN(CPI, "r%d, %d", a->rd, a->imm)
+INSN(CPSE, "r%d, r%d", a->rd, a->rr)
+INSN(DEC, "r%d", a->rd)
+INSN(DES, "%d", a->imm)
+INSN(EICALL, "")
+INSN(EIJMP, "")
+INSN(ELPM1, "")
+INSN(ELPM2, "r%d, Z", a->rd)
+INSN(ELPMX, "r%d, Z+", a->rd)
+INSN(EOR, "r%d, r%d", a->rd, a->rr)
+INSN(FMUL, "r%d, r%d", a->rd, a->rr)
+INSN(FMULS, "r%d, r%d", a->rd, a->rr)
+INSN(FMULSU, "r%d, r%d", a->rd, a->rr)
+INSN(ICALL, "")
+INSN(IJMP, "")
+INSN(IN, "r%d, $%d", a->rd, a->imm)
+INSN(INC, "r%d", a->rd)
+INSN(JMP, "0x%x", a->imm * 2)
+INSN(LAC, "Z, r%d", a->rd)
+INSN(LAS, "Z, r%d", a->rd)
+INSN(LAT, "Z, r%d", a->rd)
+INSN(LDDY, "r%d, Y+%d", a->rd, a->imm)
+INSN(LDDZ, "r%d, Z+%d", a->rd, a->imm)
+INSN(LDI, "r%d, %d", a->rd, a->imm)
+INSN(LDS, "r%d, %d", a->rd, a->imm)
+INSN(LDX1, "r%d, X", a->rd)
+INSN(LDX2, "r%d, X+", a->rd)
+INSN(LDX3, "r%d, -X", a->rd)
+INSN(LDY2, "r%d, Y+", a->rd)
+INSN(LDY3, "r%d, -Y", a->rd)
+INSN(LDZ2, "r%d, Z+", a->rd)
+INSN(LDZ3, "r%d, -Z", a->rd)
+INSN(LPM1, "")
+INSN(LPM2, "r%d, Z", a->rd)
+INSN(LPMX, "r%d, Z+", a->rd)
+INSN(LSR, "r%d", a->rd)
+INSN(MOV, "r%d, r%d", a->rd, a->rr)
+INSN(MOVW, "r%d:r%d, r%d,r:r%d", a->rd + 1, a->rd, a->rr + 1, a->rr)
+INSN(MUL, "r%d, r%d", a->rd, a->rr)
+INSN(MULS, "r%d, r%d", a->rd, a->rr)
+INSN(MULSU, "r%d, r%d", a->rd, a->rr)
+INSN(NEG, "r%d", a->rd)
+INSN(NOP, "")
+INSN(OR, "r%d, r%d", a->rd, a->rr)
+INSN(ORI, "r%d, %d", a->rd, a->imm)
+INSN(OUT, "$%d, r%d", a->imm, a->rd)
+INSN(POP, "r%d", a->rd)
+INSN(PUSH, "r%d", a->rd)
+INSN(RCALL, ".%+d", a->imm * 2)
+INSN(RET, "")
+INSN(RETI, "")
+INSN(RJMP, ".%+d", a->imm * 2)
+INSN(ROR, "r%d", a->rd)
+INSN(SBC, "r%d, r%d", a->rd, a->rr)
+INSN(SBCI, "r%d, %d", a->rd, a->imm)
+INSN(SBI, "$%d, %d", a->reg, a->bit)
+INSN(SBIC, "$%d, %d", a->reg, a->bit)
+INSN(SBIS, "$%d, %d", a->reg, a->bit)
+INSN(SBIW, "r%d:r%d, %d", a->rd + 1, a->rd, a->imm)
+INSN(SBRC, "r%d, %d", a->rr, a->bit)
+INSN(SBRS, "r%d, %d", a->rr, a->bit)
+INSN(SLEEP, "")
+INSN(SPM, "")
+INSN(SPMX, "Z+")
+INSN(STDY, "r%d, Y+%d", a->rd, a->imm)
+INSN(STDZ, "r%d, Z+%d", a->rd, a->imm)
+INSN(STS, "r%d, %d", a->rd, a->imm)
+INSN(STX1, "r%d, X", a->rr)
+INSN(STX2, "r%d, X+", a->rr)
+INSN(STX3, "r%d, -X", a->rr)
+INSN(STY2, "r%d, Y+", a->rd)
+INSN(STY3, "r%d, -Y", a->rd)
+INSN(STZ2, "r%d, Z+", a->rd)
+INSN(STZ3, "r%d, -Z", a->rd)
+INSN(SUB, "r%d, r%d", a->rd, a->rr)
+INSN(SUBI, "r%d, %d", a->rd, a->imm)
+INSN(SWAP, "r%d", a->rd)
+INSN(WDR, "")
+INSN(XCH, "Z, r%d", a->rd)
+
diff --git a/target/avr/translate.c b/target/avr/translate.c
index 941db8e168..e562e68d88 100644
--- a/target/avr/translate.c
+++ b/target/avr/translate.c
@@ -3032,6 +3032,17 @@ done_generating:

tb->size = (ctx.npc - pc_start) * 2;
tb->icount = num_insns;
+
+#ifdef DEBUG_DISAS
+ if (qemu_loglevel_mask(CPU_LOG_TB_IN_ASM)
+ && qemu_log_in_addr_range(tb->pc)) {
+ qemu_log_lock();
+ qemu_log("IN: %s\n", lookup_symbol(tb->pc));
+ log_target_disas(cs, tb->pc, tb->size);
+ qemu_log("\n");
+ qemu_log_unlock();
+ }
+#endif
}

void restore_state_to_opc(CPUAVRState *env, TranslationBlock *tb,
--
2.17.2 (Apple Git-113)

From:	Aleksandar Markovic
Subject:	Re: [PATCH v37 10/17] target/avr: Add instruction disassembly function
Date:	Mon, 2 Dec 2019 13:01:03 +0100