Re: [Qemu-devel] [PATCH v1] RISC-V: Add misa to DisasContext

[Philippe Mathieu-Daudé]

On 05/09/2018 06:39 AM, Michael Clark wrote:
> gen methods should access state from DisasContext. Add misa
> field to the DisasContext struct and remove CPURISCVState
> argument from all gen methods.
> 
> Cc: Palmer Dabbelt <address@hidden>
> Cc: Sagar Karandikar <address@hidden>
> Cc: Bastian Koppelmann <address@hidden>
> Cc: Alistair Francis <address@hidden>
> Cc: Emilio G. Cota <address@hidden>
> Signed-off-by: Michael Clark <address@hidden>

Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

> ---
>  target/riscv/translate.c | 74 
> ++++++++++++++++++++++++++----------------------
>  1 file changed, 40 insertions(+), 34 deletions(-)
> 
> diff --git a/target/riscv/translate.c b/target/riscv/translate.c
> index c0e6a044d383..5b9e5fe343d2 100644
> --- a/target/riscv/translate.c
> +++ b/target/riscv/translate.c
> @@ -44,6 +44,7 @@ typedef struct DisasContext {
>      target_ulong next_pc;
>      uint32_t opcode;
>      uint32_t flags;
> +    uint32_t misa;
>      uint32_t mem_idx;
>      int singlestep_enabled;
>      int bstate;
> @@ -82,6 +83,11 @@ static const int tcg_memop_lookup[8] = {
>  #define CASE_OP_32_64(X) case X
>  #endif
>  
> +static inline bool has_ext(DisasContext *ctx, uint32_t ext)
> +{
> +    return ctx->misa & ext;
> +}
> +
>  static void generate_exception(DisasContext *ctx, int excp)
>  {
>      tcg_gen_movi_tl(cpu_pc, ctx->pc);
> @@ -513,14 +519,13 @@ static void gen_arith_imm(DisasContext *ctx, uint32_t 
> opc, int rd,
>      tcg_temp_free(source1);
>  }
>  
> -static void gen_jal(CPURISCVState *env, DisasContext *ctx, int rd,
> -                    target_ulong imm)
> +static void gen_jal(DisasContext *ctx, int rd, target_ulong imm)
>  {
>      target_ulong next_pc;
>  
>      /* check misaligned: */
>      next_pc = ctx->pc + imm;
> -    if (!riscv_has_ext(env, RVC)) {
> +    if (!has_ext(ctx, RVC)) {
>          if ((next_pc & 0x3) != 0) {
>              gen_exception_inst_addr_mis(ctx);
>              return;
> @@ -534,8 +539,8 @@ static void gen_jal(CPURISCVState *env, DisasContext 
> *ctx, int rd,
>      ctx->bstate = BS_BRANCH;
>  }
>  
> -static void gen_jalr(CPURISCVState *env, DisasContext *ctx, uint32_t opc,
> -                     int rd, int rs1, target_long imm)
> +static void gen_jalr(DisasContext *ctx, uint32_t opc, int rd, int rs1,
> +                     target_long imm)
>  {
>      /* no chaining with JALR */
>      TCGLabel *misaligned = NULL;
> @@ -547,7 +552,7 @@ static void gen_jalr(CPURISCVState *env, DisasContext 
> *ctx, uint32_t opc,
>          tcg_gen_addi_tl(cpu_pc, cpu_pc, imm);
>          tcg_gen_andi_tl(cpu_pc, cpu_pc, (target_ulong)-2);
>  
> -        if (!riscv_has_ext(env, RVC)) {
> +        if (!has_ext(ctx, RVC)) {
>              misaligned = gen_new_label();
>              tcg_gen_andi_tl(t0, cpu_pc, 0x2);
>              tcg_gen_brcondi_tl(TCG_COND_NE, t0, 0x0, misaligned);
> @@ -572,8 +577,8 @@ static void gen_jalr(CPURISCVState *env, DisasContext 
> *ctx, uint32_t opc,
>      tcg_temp_free(t0);
>  }
>  
> -static void gen_branch(CPURISCVState *env, DisasContext *ctx, uint32_t opc,
> -                       int rs1, int rs2, target_long bimm)
> +static void gen_branch(DisasContext *ctx, uint32_t opc, int rs1, int rs2,
> +                       target_long bimm)
>  {
>      TCGLabel *l = gen_new_label();
>      TCGv source1, source2;
> @@ -610,7 +615,7 @@ static void gen_branch(CPURISCVState *env, DisasContext 
> *ctx, uint32_t opc,
>  
>      gen_goto_tb(ctx, 1, ctx->next_pc);
>      gen_set_label(l); /* branch taken */
> -    if (!riscv_has_ext(env, RVC) && ((ctx->pc + bimm) & 0x3)) {
> +    if (!has_ext(ctx, RVC) && ((ctx->pc + bimm) & 0x3)) {
>          /* misaligned */
>          gen_exception_inst_addr_mis(ctx);
>      } else {
> @@ -1313,8 +1318,8 @@ static void gen_fp_arith(DisasContext *ctx, uint32_t 
> opc, int rd,
>      }
>  }
>  
> -static void gen_system(CPURISCVState *env, DisasContext *ctx, uint32_t opc,
> -                      int rd, int rs1, int csr)
> +static void gen_system(DisasContext *ctx, uint32_t opc, int rd, int rs1,
> +                       int csr)
>  {
>      TCGv source1, csr_store, dest, rs1_pass, imm_rs1;
>      source1 = tcg_temp_new();
> @@ -1356,7 +1361,7 @@ static void gen_system(CPURISCVState *env, DisasContext 
> *ctx, uint32_t opc,
>              gen_exception_illegal(ctx);
>              break;
>          case 0x102: /* SRET */
> -            if (riscv_has_ext(env, RVS)) {
> +            if (has_ext(ctx, RVS)) {
>                  gen_helper_sret(cpu_pc, cpu_env, cpu_pc);
>                  tcg_gen_exit_tb(0); /* no chaining */
>                  ctx->bstate = BS_BRANCH;
> @@ -1497,7 +1502,7 @@ static void decode_RV32_64C0(DisasContext *ctx)
>      }
>  }
>  
> -static void decode_RV32_64C1(CPURISCVState *env, DisasContext *ctx)
> +static void decode_RV32_64C1(DisasContext *ctx)
>  {
>      uint8_t funct3 = extract32(ctx->opcode, 13, 3);
>      uint8_t rd_rs1 = GET_C_RS1(ctx->opcode);
> @@ -1517,7 +1522,7 @@ static void decode_RV32_64C1(CPURISCVState *env, 
> DisasContext *ctx)
>                        GET_C_IMM(ctx->opcode));
>  #else
>          /* C.JAL(RV32) -> jal x1, offset[11:1] */
> -        gen_jal(env, ctx, 1, GET_C_J_IMM(ctx->opcode));
> +        gen_jal(ctx, 1, GET_C_J_IMM(ctx->opcode));
>  #endif
>          break;
>      case 2:
> @@ -1596,22 +1601,22 @@ static void decode_RV32_64C1(CPURISCVState *env, 
> DisasContext *ctx)
>          break;
>      case 5:
>          /* C.J -> jal x0, offset[11:1]*/
> -        gen_jal(env, ctx, 0, GET_C_J_IMM(ctx->opcode));
> +        gen_jal(ctx, 0, GET_C_J_IMM(ctx->opcode));
>          break;
>      case 6:
>          /* C.BEQZ -> beq rs1', x0, offset[8:1]*/
>          rs1s = GET_C_RS1S(ctx->opcode);
> -        gen_branch(env, ctx, OPC_RISC_BEQ, rs1s, 0, 
> GET_C_B_IMM(ctx->opcode));
> +        gen_branch(ctx, OPC_RISC_BEQ, rs1s, 0, GET_C_B_IMM(ctx->opcode));
>          break;
>      case 7:
>          /* C.BNEZ -> bne rs1', x0, offset[8:1]*/
>          rs1s = GET_C_RS1S(ctx->opcode);
> -        gen_branch(env, ctx, OPC_RISC_BNE, rs1s, 0, 
> GET_C_B_IMM(ctx->opcode));
> +        gen_branch(ctx, OPC_RISC_BNE, rs1s, 0, GET_C_B_IMM(ctx->opcode));
>          break;
>      }
>  }
>  
> -static void decode_RV32_64C2(CPURISCVState *env, DisasContext *ctx)
> +static void decode_RV32_64C2(DisasContext *ctx)
>  {
>      uint8_t rd, rs2;
>      uint8_t funct3 = extract32(ctx->opcode, 13, 3);
> @@ -1645,7 +1650,7 @@ static void decode_RV32_64C2(CPURISCVState *env, 
> DisasContext *ctx)
>          if (extract32(ctx->opcode, 12, 1) == 0) {
>              if (rs2 == 0) {
>                  /* C.JR -> jalr x0, rs1, 0*/
> -                gen_jalr(env, ctx, OPC_RISC_JALR, 0, rd, 0);
> +                gen_jalr(ctx, OPC_RISC_JALR, 0, rd, 0);
>              } else {
>                  /* C.MV -> add rd, x0, rs2 */
>                  gen_arith(ctx, OPC_RISC_ADD, rd, 0, rs2);
> @@ -1653,11 +1658,11 @@ static void decode_RV32_64C2(CPURISCVState *env, 
> DisasContext *ctx)
>          } else {
>              if (rd == 0) {
>                  /* C.EBREAK -> ebreak*/
> -                gen_system(env, ctx, OPC_RISC_ECALL, 0, 0, 0x1);
> +                gen_system(ctx, OPC_RISC_ECALL, 0, 0, 0x1);
>              } else {
>                  if (rs2 == 0) {
>                      /* C.JALR -> jalr x1, rs1, 0*/
> -                    gen_jalr(env, ctx, OPC_RISC_JALR, 1, rd, 0);
> +                    gen_jalr(ctx, OPC_RISC_JALR, 1, rd, 0);
>                  } else {
>                      /* C.ADD -> add rd, rd, rs2 */
>                      gen_arith(ctx, OPC_RISC_ADD, rd, rd, rs2);
> @@ -1689,7 +1694,7 @@ static void decode_RV32_64C2(CPURISCVState *env, 
> DisasContext *ctx)
>      }
>  }
>  
> -static void decode_RV32_64C(CPURISCVState *env, DisasContext *ctx)
> +static void decode_RV32_64C(DisasContext *ctx)
>  {
>      uint8_t op = extract32(ctx->opcode, 0, 2);
>  
> @@ -1698,15 +1703,15 @@ static void decode_RV32_64C(CPURISCVState *env, 
> DisasContext *ctx)
>          decode_RV32_64C0(ctx);
>          break;
>      case 1:
> -        decode_RV32_64C1(env, ctx);
> +        decode_RV32_64C1(ctx);
>          break;
>      case 2:
> -        decode_RV32_64C2(env, ctx);
> +        decode_RV32_64C2(ctx);
>          break;
>      }
>  }
>  
> -static void decode_RV32_64G(CPURISCVState *env, DisasContext *ctx)
> +static void decode_RV32_64G(DisasContext *ctx)
>  {
>      int rs1;
>      int rs2;
> @@ -1741,13 +1746,13 @@ static void decode_RV32_64G(CPURISCVState *env, 
> DisasContext *ctx)
>          break;
>      case OPC_RISC_JAL:
>          imm = GET_JAL_IMM(ctx->opcode);
> -        gen_jal(env, ctx, rd, imm);
> +        gen_jal(ctx, rd, imm);
>          break;
>      case OPC_RISC_JALR:
> -        gen_jalr(env, ctx, MASK_OP_JALR(ctx->opcode), rd, rs1, imm);
> +        gen_jalr(ctx, MASK_OP_JALR(ctx->opcode), rd, rs1, imm);
>          break;
>      case OPC_RISC_BRANCH:
> -        gen_branch(env, ctx, MASK_OP_BRANCH(ctx->opcode), rs1, rs2,
> +        gen_branch(ctx, MASK_OP_BRANCH(ctx->opcode), rs1, rs2,
>                     GET_B_IMM(ctx->opcode));
>          break;
>      case OPC_RISC_LOAD:
> @@ -1820,7 +1825,7 @@ static void decode_RV32_64G(CPURISCVState *env, 
> DisasContext *ctx)
>  #endif
>          break;
>      case OPC_RISC_SYSTEM:
> -        gen_system(env, ctx, MASK_OP_SYSTEM(ctx->opcode), rd, rs1,
> +        gen_system(ctx, MASK_OP_SYSTEM(ctx->opcode), rd, rs1,
>                     (ctx->opcode & 0xFFF00000) >> 20);
>          break;
>      default:
> @@ -1829,19 +1834,19 @@ static void decode_RV32_64G(CPURISCVState *env, 
> DisasContext *ctx)
>      }
>  }
>  
> -static void decode_opc(CPURISCVState *env, DisasContext *ctx)
> +static void decode_opc(DisasContext *ctx)
>  {
>      /* check for compressed insn */
>      if (extract32(ctx->opcode, 0, 2) != 3) {
> -        if (!riscv_has_ext(env, RVC)) {
> +        if (!has_ext(ctx, RVC)) {
>              gen_exception_illegal(ctx);
>          } else {
>              ctx->next_pc = ctx->pc + 2;
> -            decode_RV32_64C(env, ctx);
> +            decode_RV32_64C(ctx);
>          }
>      } else {
>          ctx->next_pc = ctx->pc + 4;
> -        decode_RV32_64G(env, ctx);
> +        decode_RV32_64G(ctx);
>      }
>  }
>  
> @@ -1865,6 +1870,7 @@ void gen_intermediate_code(CPUState *cs, 
> TranslationBlock *tb)
>      ctx.bstate = BS_NONE;
>      ctx.flags = tb->flags;
>      ctx.mem_idx = tb->flags & TB_FLAGS_MMU_MASK;
> +    ctx.misa = env->misa;
>      ctx.frm = -1;  /* unknown rounding mode */
>  
>      num_insns = 0;
> @@ -1898,7 +1904,7 @@ void gen_intermediate_code(CPUState *cs, 
> TranslationBlock *tb)
>          }
>  
>          ctx.opcode = cpu_ldl_code(env, ctx.pc);
> -        decode_opc(env, &ctx);
> +        decode_opc(&ctx);
>          ctx.pc = ctx.next_pc;
>  
>          if (cs->singlestep_enabled) {
>