The original implementation sets $pc to the address read from the jump vector table first and links $ra with the address of the next instruction after the updated $pc. After jumping to the updated $pc and executing the next ret instruction, the program jumps to $ra, which is in the same function currently executing, which results in an infinite loop. This commit reverses the two action. Firstly, $ra is updated with the address of the next instruction after $pc, and sets $pc to the address read from the jump vector table.
Signed-off-by: Jason Chien <jason.ch...@sifive.com> --- target/riscv/insn_trans/trans_rvzce.c.inc | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/target/riscv/insn_trans/trans_rvzce.c.inc b/target/riscv/insn_trans/trans_rvzce.c.inc index 8d8a64f493..a185e2315f 100644 --- a/target/riscv/insn_trans/trans_rvzce.c.inc +++ b/target/riscv/insn_trans/trans_rvzce.c.inc @@ -293,13 +293,6 @@ static bool trans_cm_jalt(DisasContext *ctx, arg_cm_jalt *a) { REQUIRE_ZCMT(ctx); - /* - * Update pc to current for the non-unwinding exception - * that might come from cpu_ld*_code() in the helper. - */ - gen_update_pc(ctx, 0); - gen_helper_cm_jalt(cpu_pc, cpu_env, tcg_constant_i32(a->index)); - /* c.jt vs c.jalt depends on the index. */ if (a->index >= 32) { TCGv succ_pc = dest_gpr(ctx, xRA); @@ -307,6 +300,13 @@ static bool trans_cm_jalt(DisasContext *ctx, arg_cm_jalt *a) gen_set_gpr(ctx, xRA, succ_pc); } + /* + * Update pc to current for the non-unwinding exception + * that might come from cpu_ld*_code() in the helper. + */ + gen_update_pc(ctx, 0); + gen_helper_cm_jalt(cpu_pc, cpu_env, tcg_constant_i32(a->index)); + tcg_gen_lookup_and_goto_ptr(); ctx->base.is_jmp = DISAS_NORETURN; return true; -- 2.43.0