diff mbox series

[v2,2/8] target/riscv: add support for Zca and Zcf extensions

Message ID 20221113023251.11047-3-liweiwei@iscas.ac.cn
State New
Headers show
Series support subsets of code size reduction extension | expand

Commit Message

Weiwei Li Nov. 13, 2022, 2:32 a.m. UTC
Add check for Zca and Zcf extensions

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
---
 target/riscv/insn_trans/trans_rvi.c.inc |  4 ++--
 target/riscv/translate.c                | 16 ++++++++++++++--
 2 files changed, 16 insertions(+), 4 deletions(-)

Comments

Richard Henderson Nov. 13, 2022, 9:40 p.m. UTC | #1
On 11/13/22 12:32, Weiwei Li wrote:
> +        } else if ((get_xl_max(ctx) == MXL_RV32) &&
> +            !ctx->cfg_ptr->ext_zcf &&
> +            (((opcode & 0xe003) == 0x6000) ||
> +             ((opcode & 0xe003) == 0x6002) ||
> +             ((opcode & 0xe003) == 0xe000) ||
> +             ((opcode & 0xe003) == 0xe002))) {
>               gen_exception_illegal(ctx);

Why aren't you using the same c_flw solution that you do for Zcd?


r~
Weiwei Li Nov. 14, 2022, 3:17 a.m. UTC | #2
On 2022/11/14 05:40, Richard Henderson wrote:
> On 11/13/22 12:32, Weiwei Li wrote:
>> +        } else if ((get_xl_max(ctx) == MXL_RV32) &&
>> +            !ctx->cfg_ptr->ext_zcf &&
>> +            (((opcode & 0xe003) == 0x6000) ||
>> +             ((opcode & 0xe003) == 0x6002) ||
>> +             ((opcode & 0xe003) == 0xe000) ||
>> +             ((opcode & 0xe003) == 0xe002))) {
>>               gen_exception_illegal(ctx);
>
> Why aren't you using the same c_flw solution that you do for Zcd?
Yeah, it's OK for zcf intructions to use the c_flw solution.

I tried to remain the original logic for Zcf and Zcd instructions, 
However, this way is not suitable for Zcd instructions

since zcmp/zcmt instructions will overlap their encodings(but not the 
same).  So I changed the way of Zcd instructions.

Regards,

Weiwei Li

>
>
> r~
diff mbox series

Patch

diff --git a/target/riscv/insn_trans/trans_rvi.c.inc b/target/riscv/insn_trans/trans_rvi.c.inc
index 5c69b88d1e..0d73b919ce 100644
--- a/target/riscv/insn_trans/trans_rvi.c.inc
+++ b/target/riscv/insn_trans/trans_rvi.c.inc
@@ -56,7 +56,7 @@  static bool trans_jalr(DisasContext *ctx, arg_jalr *a)
     tcg_gen_andi_tl(cpu_pc, cpu_pc, (target_ulong)-2);
 
     gen_set_pc(ctx, cpu_pc);
-    if (!has_ext(ctx, RVC)) {
+    if (!ctx->cfg_ptr->ext_zca) {
         TCGv t0 = tcg_temp_new();
 
         misaligned = gen_new_label();
@@ -178,7 +178,7 @@  static bool gen_branch(DisasContext *ctx, arg_b *a, TCGCond cond)
 
     gen_set_label(l); /* branch taken */
 
-    if (!has_ext(ctx, RVC) && ((ctx->base.pc_next + a->imm) & 0x3)) {
+    if (!ctx->cfg_ptr->ext_zca && ((ctx->base.pc_next + a->imm) & 0x3)) {
         /* misaligned */
         gen_exception_inst_addr_mis(ctx);
     } else {
diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index 2ab8772ebe..0514e43fd3 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -557,7 +557,7 @@  static void gen_jal(DisasContext *ctx, int rd, target_ulong imm)
 
     /* check misaligned: */
     next_pc = ctx->base.pc_next + imm;
-    if (!has_ext(ctx, RVC)) {
+    if (!ctx->cfg_ptr->ext_zca) {
         if ((next_pc & 0x3) != 0) {
             gen_exception_inst_addr_mis(ctx);
             return;
@@ -1097,7 +1097,19 @@  static void decode_opc(CPURISCVState *env, DisasContext *ctx, uint16_t opcode)
     ctx->virt_inst_excp = false;
     /* Check for compressed insn */
     if (insn_len(opcode) == 2) {
-        if (!has_ext(ctx, RVC)) {
+        /*
+         * Zca support all of the existing C extension, excluding all
+         * compressed floating point loads and stores
+         * Zcf(RV32 only) support c.flw, c.flwsp, c.fsw, c.fswsp
+         */
+        if (!ctx->cfg_ptr->ext_zca) {
+            gen_exception_illegal(ctx);
+        } else if ((get_xl_max(ctx) == MXL_RV32) &&
+            !ctx->cfg_ptr->ext_zcf &&
+            (((opcode & 0xe003) == 0x6000) ||
+             ((opcode & 0xe003) == 0x6002) ||
+             ((opcode & 0xe003) == 0xe000) ||
+             ((opcode & 0xe003) == 0xe002))) {
             gen_exception_illegal(ctx);
         } else {
             ctx->opcode = opcode;