Message ID | 20230410141316.3317474-3-mchitale@ventanamicro.com |
---|---|
State | New |
Headers | show |
Series | Smstateen FCSR implementation | expand |
On 4/10/23 07:13, Mayuresh Chitale wrote: > The state of smstateen0.FCSR bit impacts the execution of floating point > instructions when misa.F==0. Add a field in the tb->flags which stores > the current state of smstateen0.fcsr and will be used by floating point > translation routines. Are you certain that you require a new bit? Could the same effect be achieved by forcing one or more of the existing TB_FLAGS.{FS,HS_FS} fields to 0 within cpu_get_tb_cpu_state? I.e. for the purposes of translation, pretend the FS state is DISABLED? These bits are scarce, are we are nearly out. r~
On Tue, Apr 11, 2023 at 7:17 AM Richard Henderson <richard.henderson@linaro.org> wrote: > > On 4/10/23 07:13, Mayuresh Chitale wrote: > > The state of smstateen0.FCSR bit impacts the execution of floating point > > instructions when misa.F==0. Add a field in the tb->flags which stores > > the current state of smstateen0.fcsr and will be used by floating point > > translation routines. > > Are you certain that you require a new bit? > > Could the same effect be achieved by forcing one or more of the existing > TB_FLAGS.{FS,HS_FS} fields to 0 within cpu_get_tb_cpu_state? I.e. for the purposes of > translation, pretend the FS state is DISABLED? Yes, that is correct. > > These bits are scarce, are we are nearly out. > > > r~ >
diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index 132cf06ff2..9c6b10d29a 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -653,6 +653,7 @@ FIELD(TB_FLAGS, VTA, 24, 1) FIELD(TB_FLAGS, VMA, 25, 1) /* Native debug itrigger */ FIELD(TB_FLAGS, ITRIGGER, 26, 1) +FIELD(TB_FLAGS, FCSR, 27, 1) #ifdef TARGET_RISCV32 #define riscv_cpu_mxl(env) ((void)(env), MXL_RV32) diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index f88c503cf4..1590e6e480 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -117,6 +117,11 @@ void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc, if (env->cur_pmbase != 0) { flags = FIELD_DP32(flags, TB_FLAGS, PM_BASE_ENABLED, 1); } + if (smstateen_acc_ok(env, 0, SMSTATEEN0_FCSR) == RISCV_EXCP_NONE) { + flags = FIELD_DP32(flags, TB_FLAGS, FCSR, 1); + } else { + flags = FIELD_DP32(flags, TB_FLAGS, FCSR, 0); + } *pflags = flags; } diff --git a/target/riscv/translate.c b/target/riscv/translate.c index 0ee8ee147d..4880eaeb89 100644 --- a/target/riscv/translate.c +++ b/target/riscv/translate.c @@ -77,6 +77,7 @@ typedef struct DisasContext { int frm; RISCVMXL ol; bool virt_inst_excp; + bool smstateen_fcsr_ok; bool virt_enabled; const RISCVCPUConfig *cfg_ptr; bool hlsx; @@ -1187,6 +1188,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs) ctx->itrigger = FIELD_EX32(tb_flags, TB_FLAGS, ITRIGGER); ctx->zero = tcg_constant_tl(0); ctx->virt_inst_excp = false; + ctx->smstateen_fcsr_ok = FIELD_EX32(tb_flags, TB_FLAGS, FCSR); } static void riscv_tr_tb_start(DisasContextBase *db, CPUState *cpu)
The state of smstateen0.FCSR bit impacts the execution of floating point instructions when misa.F==0. Add a field in the tb->flags which stores the current state of smstateen0.fcsr and will be used by floating point translation routines. Signed-off-by: Mayuresh Chitale <mchitale@ventanamicro.com> --- target/riscv/cpu.h | 1 + target/riscv/cpu_helper.c | 5 +++++ target/riscv/translate.c | 2 ++ 3 files changed, 8 insertions(+)