From 667ff9612b786f9bb5b70135811164b48b7d44eb Mon Sep 17 00:00:00 2001 From: Michael Walle Date: Mon, 23 Sep 2013 20:47:33 +0200 Subject: target-lm32: stop VM on illegal or unknown instruction Instead of translating the instruction to a no-op, pause the VM and display a message to the user. As a side effect, this also works for instructions where the operands are only known at runtime. Signed-off-by: Michael Walle --- target-lm32/translate.c | 106 +++++++++++++++++++++++++++++++----------------- 1 file changed, 68 insertions(+), 38 deletions(-) (limited to 'target-lm32/translate.c') diff --git a/target-lm32/translate.c b/target-lm32/translate.c index f20460ab2c..80bffc7b27 100644 --- a/target-lm32/translate.c +++ b/target-lm32/translate.c @@ -122,6 +122,12 @@ static inline void t_gen_raise_exception(DisasContext *dc, uint32_t index) tcg_temp_free_i32(tmp); } +static inline void t_gen_illegal_insn(DisasContext *dc) +{ + tcg_gen_movi_tl(cpu_pc, dc->pc); + gen_helper_ill(cpu_env); +} + static void gen_goto_tb(DisasContext *dc, int n, target_ulong dest) { TranslationBlock *tb; @@ -425,6 +431,7 @@ static void dec_divu(DisasContext *dc) if (!(dc->features & LM32_FEATURE_DIVIDE)) { qemu_log_mask(LOG_GUEST_ERROR, "hardware divider is not available\n"); + t_gen_illegal_insn(dc); return; } @@ -504,6 +511,7 @@ static void dec_modu(DisasContext *dc) if (!(dc->features & LM32_FEATURE_DIVIDE)) { qemu_log_mask(LOG_GUEST_ERROR, "hardware divider is not available\n"); + t_gen_illegal_insn(dc); return; } @@ -527,6 +535,7 @@ static void dec_mul(DisasContext *dc) if (!(dc->features & LM32_FEATURE_MULTIPLY)) { qemu_log_mask(LOG_GUEST_ERROR, "hardware multiplier is not available\n"); + t_gen_illegal_insn(dc); return; } @@ -591,21 +600,21 @@ static void dec_orhi(DisasContext *dc) static void dec_scall(DisasContext *dc) { - if (dc->imm5 == 7) { - LOG_DIS("scall\n"); - } else if (dc->imm5 == 2) { + switch (dc->imm5) { + case 2: LOG_DIS("break\n"); - } else { - qemu_log_mask(LOG_GUEST_ERROR, "invalid opcode @0x%x", dc->pc); - return; - } - - if (dc->imm5 == 7) { - tcg_gen_movi_tl(cpu_pc, dc->pc); - t_gen_raise_exception(dc, EXCP_SYSTEMCALL); - } else { tcg_gen_movi_tl(cpu_pc, dc->pc); t_gen_raise_exception(dc, EXCP_BREAKPOINT); + break; + case 7: + LOG_DIS("scall\n"); + tcg_gen_movi_tl(cpu_pc, dc->pc); + t_gen_raise_exception(dc, EXCP_SYSTEMCALL); + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, "invalid opcode @0x%x", dc->pc); + t_gen_illegal_insn(dc); + break; } } @@ -681,6 +690,7 @@ static void dec_sextb(DisasContext *dc) if (!(dc->features & LM32_FEATURE_SIGN_EXTEND)) { qemu_log_mask(LOG_GUEST_ERROR, "hardware sign extender is not available\n"); + t_gen_illegal_insn(dc); return; } @@ -694,6 +704,7 @@ static void dec_sexth(DisasContext *dc) if (!(dc->features & LM32_FEATURE_SIGN_EXTEND)) { qemu_log_mask(LOG_GUEST_ERROR, "hardware sign extender is not available\n"); + t_gen_illegal_insn(dc); return; } @@ -722,6 +733,7 @@ static void dec_sl(DisasContext *dc) if (!(dc->features & LM32_FEATURE_SHIFT)) { qemu_log_mask(LOG_GUEST_ERROR, "hardware shifter is not available\n"); + t_gen_illegal_insn(dc); return; } @@ -743,24 +755,32 @@ static void dec_sr(DisasContext *dc) LOG_DIS("sr r%d, r%d, r%d\n", dc->r2, dc->r0, dc->r1); } - if (!(dc->features & LM32_FEATURE_SHIFT)) { - if (dc->format == OP_FMT_RI) { - /* TODO: check r1 == 1 during runtime */ - } else { - if (dc->imm5 != 1) { - qemu_log_mask(LOG_GUEST_ERROR, - "hardware shifter is not available\n"); - return; - } - } - } - + /* The real CPU (w/o hardware shifter) only supports right shift by exactly + * one bit */ if (dc->format == OP_FMT_RI) { + if (!(dc->features & LM32_FEATURE_SHIFT) && (dc->imm5 != 1)) { + qemu_log_mask(LOG_GUEST_ERROR, + "hardware shifter is not available\n"); + t_gen_illegal_insn(dc); + return; + } tcg_gen_sari_tl(cpu_R[dc->r1], cpu_R[dc->r0], dc->imm5); } else { - TCGv t0 = tcg_temp_new(); + int l1 = gen_new_label(); + int l2 = gen_new_label(); + TCGv t0 = tcg_temp_local_new(); tcg_gen_andi_tl(t0, cpu_R[dc->r1], 0x1f); + + if (!(dc->features & LM32_FEATURE_SHIFT)) { + tcg_gen_brcondi_tl(TCG_COND_EQ, t0, 1, l1); + t_gen_illegal_insn(dc); + tcg_gen_br(l2); + } + + gen_set_label(l1); tcg_gen_sar_tl(cpu_R[dc->r2], cpu_R[dc->r0], t0); + gen_set_label(l2); + tcg_temp_free(t0); } } @@ -773,24 +793,30 @@ static void dec_sru(DisasContext *dc) LOG_DIS("sru r%d, r%d, r%d\n", dc->r2, dc->r0, dc->r1); } - if (!(dc->features & LM32_FEATURE_SHIFT)) { - if (dc->format == OP_FMT_RI) { - /* TODO: check r1 == 1 during runtime */ - } else { - if (dc->imm5 != 1) { - qemu_log_mask(LOG_GUEST_ERROR, - "hardware shifter is not available\n"); - return; - } - } - } - if (dc->format == OP_FMT_RI) { + if (!(dc->features & LM32_FEATURE_SHIFT) && (dc->imm5 != 1)) { + qemu_log_mask(LOG_GUEST_ERROR, + "hardware shifter is not available\n"); + t_gen_illegal_insn(dc); + return; + } tcg_gen_shri_tl(cpu_R[dc->r1], cpu_R[dc->r0], dc->imm5); } else { - TCGv t0 = tcg_temp_new(); + int l1 = gen_new_label(); + int l2 = gen_new_label(); + TCGv t0 = tcg_temp_local_new(); tcg_gen_andi_tl(t0, cpu_R[dc->r1], 0x1f); + + if (!(dc->features & LM32_FEATURE_SHIFT)) { + tcg_gen_brcondi_tl(TCG_COND_EQ, t0, 1, l1); + t_gen_illegal_insn(dc); + tcg_gen_br(l2); + } + + gen_set_label(l1); tcg_gen_shr_tl(cpu_R[dc->r2], cpu_R[dc->r0], t0); + gen_set_label(l2); + tcg_temp_free(t0); } } @@ -819,6 +845,7 @@ static void dec_user(DisasContext *dc) LOG_DIS("user"); qemu_log_mask(LOG_GUEST_ERROR, "user instruction undefined\n"); + t_gen_illegal_insn(dc); } static void dec_wcsr(DisasContext *dc) @@ -886,6 +913,7 @@ static void dec_wcsr(DisasContext *dc) if (dc->num_breakpoints <= no) { qemu_log_mask(LOG_GUEST_ERROR, "breakpoint #%i is not available\n", no); + t_gen_illegal_insn(dc); break; } gen_helper_wcsr_bp(cpu_env, cpu_R[dc->r1], tcg_const_i32(no)); @@ -898,6 +926,7 @@ static void dec_wcsr(DisasContext *dc) if (dc->num_watchpoints <= no) { qemu_log_mask(LOG_GUEST_ERROR, "watchpoint #%i is not available\n", no); + t_gen_illegal_insn(dc); break; } gen_helper_wcsr_wp(cpu_env, cpu_R[dc->r1], tcg_const_i32(no)); @@ -956,6 +985,7 @@ static void dec_xor(DisasContext *dc) static void dec_ill(DisasContext *dc) { qemu_log_mask(LOG_GUEST_ERROR, "invalid opcode 0x%02x\n", dc->opcode); + t_gen_illegal_insn(dc); } typedef void (*DecoderInfo)(DisasContext *dc); -- cgit v1.2.3