target/riscv/insn_trans/trans_rvzicbo.c.inc: save opcode before helpers

All helpers from this file can trigger ILLEGAL_INSN exceptions via
check_zicbo_envcfg() directly, bypassing the usual exception code from
translate.c.   If we don't save the opcode before each helper,
riscv_raise_exception() is triggered and env->bins won't be unwind during
cpu_loop_exit_restore() (code path cpu_restore_state ->
cpu_restore_state_from_tb() -> restore_state_to_opc()).

And finally, in riscv_cpu_do_interrupt(), we will set (m)tval = 0 when we can,
instead, set it to the cbo opcode that generated the exception.

Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/3380
Signed-off-by: Daniel Henrique Barboza <daniel.barboza@oss.qualcomm.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20260520214704.1943652-1-daniel.barboza@oss.qualcomm.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
(cherry picked from commit d6c5855c76b2ea849adb0fb91379dbb1e5a94dca)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

1 files changed, 8 insertions, 0 deletions

diff --git a/target/riscv/insn_trans/trans_rvzicbo.c.inc b/target/riscv/insn_trans/trans_rvzicbo.c.inc
index 15711c3140..096f7dde27 100644
--- a/target/riscv/insn_trans/trans_rvzicbo.c.inc
+++ b/target/riscv/insn_trans/trans_rvzicbo.c.inc
@@ -33,6 +33,8 @@ static bool trans_cbo_clean(DisasContext *ctx, arg_cbo_clean *a)
     REQUIRE_ZICBOM(ctx);
     TCGv src = get_address(ctx, a->rs1, 0);
 
+    /* The helper may raise ILLEGAL_INSN -- record binv for unwind. */
+    decode_save_opc(ctx, 0);
     gen_helper_cbo_clean_flush(tcg_env, src);
     return true;
 }
@@ -42,6 +44,8 @@ static bool trans_cbo_flush(DisasContext *ctx, arg_cbo_flush *a)
     REQUIRE_ZICBOM(ctx);
     TCGv src = get_address(ctx, a->rs1, 0);
 
+    /* The helper may raise ILLEGAL_INSN -- record binv for unwind. */
+    decode_save_opc(ctx, 0);
     gen_helper_cbo_clean_flush(tcg_env, src);
     return true;
 }
@@ -51,6 +55,8 @@ static bool trans_cbo_inval(DisasContext *ctx, arg_cbo_inval *a)
     REQUIRE_ZICBOM(ctx);
     TCGv src = get_address(ctx, a->rs1, 0);
 
+    /* The helper may raise ILLEGAL_INSN -- record binv for unwind. */
+    decode_save_opc(ctx, 0);
     gen_helper_cbo_inval(tcg_env, src);
     return true;
 }
@@ -60,6 +66,8 @@ static bool trans_cbo_zero(DisasContext *ctx, arg_cbo_zero *a)
     REQUIRE_ZICBOZ(ctx);
     TCGv src = get_address(ctx, a->rs1, 0);
 
+    /* The helper may raise ILLEGAL_INSN -- record binv for unwind. */
+    decode_save_opc(ctx, 0);
     gen_helper_cbo_zero(tcg_env, src);
     return true;
 }