[PATCH v2 39/52] disas/riscv: Fix isa decoding of rev8

The encoding of rev8 is different for rv32 and rv64.

Cc: [email protected]
Fixes: 02c1b569a15 ("disas/riscv: Add Zb[abcs] instructions")
Reviewed-by: Alistair Francis <[email protected]>
Signed-off-by: Richard Henderson <[email protected]>
---
 disas/riscv.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/disas/riscv.c b/disas/riscv.c
index 5624e7f60a..787340e811 100644
--- a/disas/riscv.c
+++ b/disas/riscv.c
@@ -3292,8 +3292,16 @@ static const rv_opcode_data *decode_inst_opcode(rv_decode *dec, rv_isa isa)
                 case 0b01100: op = rv_op_rori; break;
                 case 0b01101:
                     switch ((inst >> 20) & 0b1111111) {
-                    case 0b0011000: op = rv_op_rev8; break;
-                    case 0b0111000: op = rv_op_rev8; break;
+                    case 0b0011000:
+                        if (isa == rv32) {
+                            op = rv_op_rev8;
+                        }
+                        break;
+                    case 0b0111000:
+                        if (isa == rv64) {
+                            op = rv_op_rev8;
+                        }
+                        break;
                     case 0b0000111: op = rv_op_brev8; break;
                     }
                     break;
-- 
2.43.0