translate-all: define and use DEBUG_TB_CHECK_GATE

This prevents bit rot by ensuring the debug code is compiled when
building a user-mode target.

Unfortunately the helpers are user-mode-only so we cannot fully
get rid of the ifdef checks. Add a comment to explain this.

Backports commit 6eb062abd66611333056633899d3f09c2e795f4c from qemu
This commit is contained in:
Emilio G. Cota 2018-03-05 02:51:44 -05:00 committed by Lioncash
parent f778c02bbc
commit 7bd35ab27d
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@ -83,6 +83,12 @@
#undef DEBUG_TB_CHECK
#endif
#ifdef DEBUG_TB_CHECK
#define DEBUG_TB_CHECK_GATE 1
#else
#define DEBUG_TB_CHECK_GATE 0
#endif
/* Access to the various translations structures need to be serialised via locks
* for consistency. This is automatic for SoftMMU based system
* emulation due to its single threaded nature. In user-mode emulation
@ -972,7 +978,13 @@ void tb_flush(CPUState *cpu)
tcg_ctx->tb_ctx.tb_flush_count++;
}
#ifdef DEBUG_TB_CHECK
/*
* Formerly ifdef DEBUG_TB_CHECK. These debug functions are user-mode-only,
* so in order to prevent bit rot we compile them unconditionally in user-mode,
* and let the optimizer get rid of them by wrapping their user-only callers
* with if (DEBUG_TB_CHECK_GATE).
*/
#ifdef CONFIG_USER_ONLY
/* verify that all the pages have correct rights for code
*
@ -1017,7 +1029,7 @@ static void tb_page_check(struct uc_struct *uc)
}
}
#endif
#endif /* CONFIG_USER_ONLY */
static inline void tb_hash_remove(TranslationBlock **ptb, TranslationBlock *tb)
{
@ -1295,8 +1307,10 @@ static void tb_link_page(struct uc_struct *uc,
tb->phys_hash_next = *ptb;
*ptb = tb;
#ifdef DEBUG_TB_CHECK
tb_page_check();
#ifdef CONFIG_USER_ONLY
if (DEBUG_TB_CHECK_GATE) {
tb_page_check();
}
#endif
}
@ -2225,8 +2239,10 @@ int page_unprotect(struct uc_struct *uc, target_ulong address, uintptr_t pc)
/* and since the content will be modified, we must invalidate
the corresponding translated code. */
current_tb_invalidated |= tb_invalidate_phys_page(addr, pc);
#ifdef DEBUG_TB_CHECK
tb_invalidate_check(addr);
#ifdef CONFIG_USER_ONLY
if (DEBUG_TB_CHECK_GATE) {
tb_invalidate_check(addr);
}
#endif
}
mprotect((void *)g2h(host_start), uc->qemu_host_page_size,