tcg: Sanity check goto_tb input

Checking that we don't try for idx != [01] is trivial.  Checking
that we don't issue more than one of any index requires a tad
more data and some ifdefs protecting that new variable.

Signed-off-by: Richard Henderson <rth@twiddle.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
This commit is contained in:
Richard Henderson 2012-09-21 17:18:16 -07:00 committed by Aurelien Jarno
parent 717e70368b
commit 0a209d4bb1
3 changed files with 13 additions and 1 deletions

View File

@ -2275,8 +2275,15 @@ static inline void tcg_gen_exit_tb(tcg_target_long val)
tcg_gen_op1i(INDEX_op_exit_tb, val);
}
static inline void tcg_gen_goto_tb(int idx)
static inline void tcg_gen_goto_tb(unsigned idx)
{
/* We only support two chained exits. */
tcg_debug_assert(idx <= 1);
#ifdef CONFIG_DEBUG_TCG
/* Verify that we havn't seen this numbered exit before. */
tcg_debug_assert((tcg_ctx.goto_tb_issue_mask & (1 << idx)) == 0);
tcg_ctx.goto_tb_issue_mask |= 1 << idx;
#endif
tcg_gen_op1i(INDEX_op_goto_tb, idx);
}

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@ -298,6 +298,10 @@ void tcg_func_start(TCGContext *s)
s->nb_labels = 0;
s->current_frame_offset = s->frame_start;
#ifdef CONFIG_DEBUG_TCG
s->goto_tb_issue_mask = 0;
#endif
gen_opc_ptr = gen_opc_buf;
gen_opparam_ptr = gen_opparam_buf;
}

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@ -390,6 +390,7 @@ struct TCGContext {
#ifdef CONFIG_DEBUG_TCG
int temps_in_use;
int goto_tb_issue_mask;
#endif
};