diff options
author | Richard Henderson <richard.henderson@linaro.org> | 2022-04-21 08:17:12 -0700 |
---|---|---|
committer | Richard Henderson <richard.henderson@linaro.org> | 2022-04-26 08:16:41 -0700 |
commit | 345b7a8757e89a8f70a1fa09c6d51310650ef8be (patch) | |
tree | 57adcb4bfe3cb0e3d115c846475b5113989d388e /target/nios2 | |
parent | e8d12542ee5646843c5557db3c78a6c29dc6bf29 (diff) |
target/nios2: Support division error exception
Division may (optionally) raise a division exception.
Since the linux kernel has been prepared for this for
some time, enable it by default.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220421151735.31996-42-richard.henderson@linaro.org>
Diffstat (limited to 'target/nios2')
-rw-r--r-- | target/nios2/cpu.c | 1 | ||||
-rw-r--r-- | target/nios2/cpu.h | 2 | ||||
-rw-r--r-- | target/nios2/helper.c | 4 | ||||
-rw-r--r-- | target/nios2/helper.h | 2 | ||||
-rw-r--r-- | target/nios2/op_helper.c | 29 | ||||
-rw-r--r-- | target/nios2/translate.c | 60 |
6 files changed, 58 insertions, 40 deletions
diff --git a/target/nios2/cpu.c b/target/nios2/cpu.c index 58e6ad0462..54e7071907 100644 --- a/target/nios2/cpu.c +++ b/target/nios2/cpu.c @@ -263,6 +263,7 @@ static int nios2_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) } static Property nios2_properties[] = { + DEFINE_PROP_BOOL("diverr_present", Nios2CPU, diverr_present, true), DEFINE_PROP_BOOL("mmu_present", Nios2CPU, mmu_present, true), /* ALTR,pid-num-bits */ DEFINE_PROP_UINT32("mmu_pid_num_bits", Nios2CPU, pid_num_bits, 8), diff --git a/target/nios2/cpu.h b/target/nios2/cpu.h index 08284d7927..4d63006ffe 100644 --- a/target/nios2/cpu.h +++ b/target/nios2/cpu.h @@ -207,7 +207,9 @@ struct ArchCPU { CPUNegativeOffsetState neg; CPUNios2State env; + bool diverr_present; bool mmu_present; + uint32_t pid_num_bits; uint32_t tlb_num_ways; uint32_t tlb_num_entries; diff --git a/target/nios2/helper.c b/target/nios2/helper.c index 4d9085f22f..c5a2dd65b1 100644 --- a/target/nios2/helper.c +++ b/target/nios2/helper.c @@ -119,6 +119,9 @@ void nios2_cpu_do_interrupt(CPUState *cs) case EXCP_UNALIGND: name = "Misaligned (destination)"; break; + case EXCP_DIV: + name = "DIV error"; + break; case EXCP_TRAP: name = "TRAP insn"; break; @@ -187,6 +190,7 @@ void nios2_cpu_do_interrupt(CPUState *cs) case EXCP_SUPERI: case EXCP_ILLEGAL: + case EXCP_DIV: case EXCP_TRAP: do_exception(cpu, cpu->exception_addr, 0, false); break; diff --git a/target/nios2/helper.h b/target/nios2/helper.h index 525b6b685b..6f5ec60b0d 100644 --- a/target/nios2/helper.h +++ b/target/nios2/helper.h @@ -19,6 +19,8 @@ */ DEF_HELPER_FLAGS_2(raise_exception, TCG_CALL_NO_WG, noreturn, env, i32) +DEF_HELPER_FLAGS_3(divs, TCG_CALL_NO_WG, s32, env, s32, s32) +DEF_HELPER_FLAGS_3(divu, TCG_CALL_NO_WG, i32, env, i32, i32) #if !defined(CONFIG_USER_ONLY) DEF_HELPER_3(eret, noreturn, env, i32, i32) diff --git a/target/nios2/op_helper.c b/target/nios2/op_helper.c index 49fccf2c2c..a19b504b0e 100644 --- a/target/nios2/op_helper.c +++ b/target/nios2/op_helper.c @@ -31,6 +31,35 @@ void helper_raise_exception(CPUNios2State *env, uint32_t index) cpu_loop_exit(cs); } +static void maybe_raise_div(CPUNios2State *env, uintptr_t ra) +{ + Nios2CPU *cpu = env_archcpu(env); + CPUState *cs = env_cpu(env); + + if (cpu->diverr_present) { + cs->exception_index = EXCP_DIV; + cpu_loop_exit_restore(cs, ra); + } +} + +int32_t helper_divs(CPUNios2State *env, int32_t num, int32_t den) +{ + if (unlikely(den == 0) || unlikely(den == -1 && num == INT32_MIN)) { + maybe_raise_div(env, GETPC()); + return num; /* undefined */ + } + return num / den; +} + +uint32_t helper_divu(CPUNios2State *env, uint32_t num, uint32_t den) +{ + if (unlikely(den == 0)) { + maybe_raise_div(env, GETPC()); + return num; /* undefined */ + } + return num / den; +} + #ifndef CONFIG_USER_ONLY void helper_eret(CPUNios2State *env, uint32_t new_status, uint32_t new_pc) { diff --git a/target/nios2/translate.c b/target/nios2/translate.c index b8d75207a4..b27269bf08 100644 --- a/target/nios2/translate.c +++ b/target/nios2/translate.c @@ -654,59 +654,39 @@ gen_r_shift_s(ror, rotr_tl) static void divs(DisasContext *dc, uint32_t code, uint32_t flags) { R_TYPE(instr, (code)); + TCGv dest; - /* Stores into R_ZERO are ignored */ - if (unlikely(instr.c == R_ZERO)) { - return; + if (instr.c == R_ZERO) { + dest = tcg_temp_new(); + } else { + dest = cpu_R[instr.c]; } - TCGv t0 = tcg_temp_new(); - TCGv t1 = tcg_temp_new(); - TCGv t2 = tcg_temp_new(); - TCGv t3 = tcg_temp_new(); + gen_helper_divs(dest, cpu_env, + load_gpr(dc, instr.a), load_gpr(dc, instr.b)); - tcg_gen_ext32s_tl(t0, load_gpr(dc, instr.a)); - tcg_gen_ext32s_tl(t1, load_gpr(dc, instr.b)); - tcg_gen_setcondi_tl(TCG_COND_EQ, t2, t0, INT_MIN); - tcg_gen_setcondi_tl(TCG_COND_EQ, t3, t1, -1); - tcg_gen_and_tl(t2, t2, t3); - tcg_gen_setcondi_tl(TCG_COND_EQ, t3, t1, 0); - tcg_gen_or_tl(t2, t2, t3); - tcg_gen_movi_tl(t3, 0); - tcg_gen_movcond_tl(TCG_COND_NE, t1, t2, t3, t2, t1); - tcg_gen_div_tl(cpu_R[instr.c], t0, t1); - tcg_gen_ext32s_tl(cpu_R[instr.c], cpu_R[instr.c]); - - tcg_temp_free(t3); - tcg_temp_free(t2); - tcg_temp_free(t1); - tcg_temp_free(t0); + if (instr.c == R_ZERO) { + tcg_temp_free(dest); + } } static void divu(DisasContext *dc, uint32_t code, uint32_t flags) { R_TYPE(instr, (code)); + TCGv dest; - /* Stores into R_ZERO are ignored */ - if (unlikely(instr.c == R_ZERO)) { - return; + if (instr.c == R_ZERO) { + dest = tcg_temp_new(); + } else { + dest = cpu_R[instr.c]; } - TCGv t0 = tcg_temp_new(); - TCGv t1 = tcg_temp_new(); - TCGv t2 = tcg_const_tl(0); - TCGv t3 = tcg_const_tl(1); + gen_helper_divu(dest, cpu_env, + load_gpr(dc, instr.a), load_gpr(dc, instr.b)); - tcg_gen_ext32u_tl(t0, load_gpr(dc, instr.a)); - tcg_gen_ext32u_tl(t1, load_gpr(dc, instr.b)); - tcg_gen_movcond_tl(TCG_COND_EQ, t1, t1, t2, t3, t1); - tcg_gen_divu_tl(cpu_R[instr.c], t0, t1); - tcg_gen_ext32s_tl(cpu_R[instr.c], cpu_R[instr.c]); - - tcg_temp_free(t3); - tcg_temp_free(t2); - tcg_temp_free(t1); - tcg_temp_free(t0); + if (instr.c == R_ZERO) { + tcg_temp_free(dest); + } } static void trap(DisasContext *dc, uint32_t code, uint32_t flags) |