[PATCH v2 38/52] disas/riscv: Fix rv32 encoding of zext.h

For rv64, pack with rs2 = 0 does not encode zext.h.

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 | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/disas/riscv.c b/disas/riscv.c
index e650ad7688..5624e7f60a 100644
--- a/disas/riscv.c
+++ b/disas/riscv.c
@@ -3506,9 +3506,10 @@ static const rv_opcode_data *decode_inst_opcode(rv_decode *dec, rv_isa isa)
             case 14: op = rv_op_rem; break;
             case 15: op = rv_op_remu; break;
             case 36:
-                switch ((inst >> 20) & 0b11111) {
-                case 0: op = rv_op_zext_h; break;
-                default: op = rv_op_pack; break;
+                if (isa == rv32 && !((inst >> 20) & 0b11111)) {
+                    op = rv_op_zext_h;
+                } else {
+                    op = rv_op_pack;
                 }
                 break;
             case 39: op = rv_op_packh; break;
-- 
2.43.0