target/riscv: Convert quadrant 0 of RVXC insns to decodetree

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Peer Adelt <peer.adelt@hni.uni-paderborn.de>

1 files changed, 16 insertions, 37 deletions

diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index 02f64ed8a7..0106fa8d51 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -803,27 +803,6 @@ static void decode_RV32_64C0(DisasContext *ctx)
     uint8_t rs1s = GET_C_RS1S(ctx->opcode);
 
     switch (funct3) {
-    case 0:
-        /* illegal */
-        if (ctx->opcode == 0) {
-            gen_exception_illegal(ctx);
-        } else {
-            /* C.ADDI4SPN -> addi rd', x2, zimm[9:2]*/
-            gen_arith_imm(ctx, OPC_RISC_ADDI, rd_rs2, 2,
-                          GET_C_ADDI4SPN_IMM(ctx->opcode));
-        }
-        break;
-    case 1:
-        /* C.FLD -> fld rd', offset[7:3](rs1')*/
-        gen_fp_load(ctx, OPC_RISC_FLD, rd_rs2, rs1s,
-                    GET_C_LD_IMM(ctx->opcode));
-        /* C.LQ(RV128) */
-        break;
-    case 2:
-        /* C.LW -> lw rd', offset[6:2](rs1') */
-        gen_load(ctx, OPC_RISC_LW, rd_rs2, rs1s,
-                 GET_C_LW_IMM(ctx->opcode));
-        break;
     case 3:
 #if defined(TARGET_RISCV64)
         /* C.LD(RV64/128) -> ld rd', offset[7:3](rs1')*/
@@ -835,21 +814,6 @@ static void decode_RV32_64C0(DisasContext *ctx)
                     GET_C_LW_IMM(ctx->opcode));
 #endif
         break;
-    case 4:
-        /* reserved */
-        gen_exception_illegal(ctx);
-        break;
-    case 5:
-        /* C.FSD(RV32/64) -> fsd rs2', offset[7:3](rs1') */
-        gen_fp_store(ctx, OPC_RISC_FSD, rs1s, rd_rs2,
-                     GET_C_LD_IMM(ctx->opcode));
-        /* C.SQ (RV128) */
-        break;
-    case 6:
-        /* C.SW -> sw rs2', offset[6:2](rs1')*/
-        gen_store(ctx, OPC_RISC_SW, rs1s, rd_rs2,
-                  GET_C_LW_IMM(ctx->opcode));
-        break;
     case 7:
 #if defined(TARGET_RISCV64)
         /* C.SD (RV64/128) -> sd rs2', offset[7:3](rs1')*/
@@ -1079,6 +1043,8 @@ static void decode_RV32_64C(DisasContext *ctx)
         return imm << amount;                 \
     }
 EX_SH(1)
+EX_SH(2)
+EX_SH(3)
 EX_SH(12)
 
 #define REQUIRE_EXT(ctx, ext) do { \
@@ -1087,6 +1053,11 @@ EX_SH(12)
     }                              \
 } while (0)
 
+static int ex_rvc_register(int reg)
+{
+    return 8 + reg;
+}
+
 bool decode_insn32(DisasContext *ctx, uint32_t insn);
 /* Include the auto-generated decoder for 32 bit insn */
 #include "decode_insn32.inc.c"
@@ -1098,6 +1069,11 @@ bool decode_insn32(DisasContext *ctx, uint32_t insn);
 #include "insn_trans/trans_rvd.inc.c"
 #include "insn_trans/trans_privileged.inc.c"
 
+bool decode_insn16(DisasContext *ctx, uint16_t insn);
+/* auto-generated decoder*/
+#include "decode_insn16.inc.c"
+#include "insn_trans/trans_rvc.inc.c"
+
 static void decode_RV32_64G(DisasContext *ctx)
 {
     int rs1, rd;
@@ -1131,7 +1107,10 @@ static void decode_opc(DisasContext *ctx)
             gen_exception_illegal(ctx);
         } else {
             ctx->pc_succ_insn = ctx->base.pc_next + 2;
-            decode_RV32_64C(ctx);
+            if (!decode_insn16(ctx, ctx->opcode)) {
+                /* fall back to old decoder */
+                decode_RV32_64C(ctx);
+            }
         }
     } else {
         ctx->pc_succ_insn = ctx->base.pc_next + 4;