From 1279f323d67b482f942c411d8a705fa9cf36e372 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Tue, 22 Mar 2016 14:59:20 +0000 Subject: [PATCH] tcg: reorganize tb_find_physical loop MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Put some comments and improve code structure. This should help reading the code. Signed-off-by: Alex Bennée [Sergey Fedorov: provide commit message; bring back resetting of tb_invalidated_flag] Signed-off-by: Sergey Fedorov Reviewed-by: Richard Henderson Signed-off-by: Richard Henderson --- cpu-exec.c | 44 ++++++++++++++++++++++++-------------------- 1 file changed, 24 insertions(+), 20 deletions(-) diff --git a/cpu-exec.c b/cpu-exec.c index f984dc71cb..02a49070b9 100644 --- a/cpu-exec.c +++ b/cpu-exec.c @@ -223,10 +223,9 @@ static TranslationBlock *tb_find_physical(CPUState *cpu, uint32_t flags) { CPUArchState *env = (CPUArchState *)cpu->env_ptr; - TranslationBlock *tb, **ptb1; + TranslationBlock *tb, **tb_hash_head, **ptb1; unsigned int h; tb_page_addr_t phys_pc, phys_page1; - target_ulong virt_page2; tcg_ctx.tb_ctx.tb_invalidated_flag = 0; @@ -234,37 +233,42 @@ static TranslationBlock *tb_find_physical(CPUState *cpu, phys_pc = get_page_addr_code(env, pc); phys_page1 = phys_pc & TARGET_PAGE_MASK; h = tb_phys_hash_func(phys_pc); - ptb1 = &tcg_ctx.tb_ctx.tb_phys_hash[h]; - for(;;) { - tb = *ptb1; - if (!tb) { - return NULL; - } + + /* Start at head of the hash entry */ + ptb1 = tb_hash_head = &tcg_ctx.tb_ctx.tb_phys_hash[h]; + tb = *ptb1; + + while (tb) { if (tb->pc == pc && tb->page_addr[0] == phys_page1 && tb->cs_base == cs_base && tb->flags == flags) { - /* check next page if needed */ - if (tb->page_addr[1] != -1) { - tb_page_addr_t phys_page2; - virt_page2 = (pc & TARGET_PAGE_MASK) + - TARGET_PAGE_SIZE; - phys_page2 = get_page_addr_code(env, virt_page2); + if (tb->page_addr[1] == -1) { + /* done, we have a match */ + break; + } else { + /* check next page if needed */ + target_ulong virt_page2 = (pc & TARGET_PAGE_MASK) + + TARGET_PAGE_SIZE; + tb_page_addr_t phys_page2 = get_page_addr_code(env, virt_page2); + if (tb->page_addr[1] == phys_page2) { break; } - } else { - break; } } + ptb1 = &tb->phys_hash_next; + tb = *ptb1; } - /* Move the TB to the head of the list */ - *ptb1 = tb->phys_hash_next; - tb->phys_hash_next = tcg_ctx.tb_ctx.tb_phys_hash[h]; - tcg_ctx.tb_ctx.tb_phys_hash[h] = tb; + if (tb) { + /* Move the TB to the head of the list */ + *ptb1 = tb->phys_hash_next; + tb->phys_hash_next = *tb_hash_head; + *tb_hash_head = tb; + } return tb; }