target/riscv: Activate decodetree and implemnt LUI & AUIPC

for now only LUI & AUIPC are decoded and translated. If decodetree fails, we
fall back to the old decoder.

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

1 files changed, 17 insertions, 14 deletions

diff --git a/target/riscv/translate.c b/target/riscv/translate.c
index b7176cbf98..a273ac8274 100644
--- a/target/riscv/translate.c
+++ b/target/riscv/translate.c
@@ -1874,6 +1874,19 @@ static void decode_RV32_64C(DisasContext *ctx)
     }
 }
 
+#define EX_SH(amount) \
+    static int ex_shift_##amount(int imm) \
+    {                                         \
+        return imm << amount;                 \
+    }
+EX_SH(12)
+
+bool decode_insn32(DisasContext *ctx, uint32_t insn);
+/* Include the auto-generated decoder for 32 bit insn */
+#include "decode_insn32.inc.c"
+/* Include insn module translation function */
+#include "insn_trans/trans_rvi.inc.c"
+
 static void decode_RV32_64G(DisasContext *ctx)
 {
     int rs1;
@@ -1894,19 +1907,6 @@ static void decode_RV32_64G(DisasContext *ctx)
     imm = GET_IMM(ctx->opcode);
 
     switch (op) {
-    case OPC_RISC_LUI:
-        if (rd == 0) {
-            break; /* NOP */
-        }
-        tcg_gen_movi_tl(cpu_gpr[rd], sextract64(ctx->opcode, 12, 20) << 12);
-        break;
-    case OPC_RISC_AUIPC:
-        if (rd == 0) {
-            break; /* NOP */
-        }
-        tcg_gen_movi_tl(cpu_gpr[rd], (sextract64(ctx->opcode, 12, 20) << 12) +
-               ctx->base.pc_next);
-        break;
     case OPC_RISC_JAL:
         imm = GET_JAL_IMM(ctx->opcode);
         gen_jal(ctx, rd, imm);
@@ -2011,7 +2011,10 @@ static void decode_opc(DisasContext *ctx)
         }
     } else {
         ctx->pc_succ_insn = ctx->base.pc_next + 4;
-        decode_RV32_64G(ctx);
+        if (!decode_insn32(ctx, ctx->opcode)) {
+            /* fallback to old decoder */
+            decode_RV32_64G(ctx);
+        }
     }
 }