From b0a0794a0f16e2160d8d35b14cca8f5e81b8b67e Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 9 Mar 2021 08:45:58 -0800 Subject: [PATCH] tcg: Re-order tcg_region_init vs tcg_prologue_init MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Instead of delaying tcg_region_init until after tcg_prologue_init is complete, do tcg_region_init first and let tcg_prologue_init shrink the first region by the size of the generated prologue. Reviewed-by: Luis Pires Reviewed-by: Alex Bennée Signed-off-by: Richard Henderson --- accel/tcg/tcg-all.c | 11 --------- accel/tcg/translate-all.c | 3 +++ bsd-user/main.c | 1 - linux-user/main.c | 1 - tcg/tcg.c | 52 ++++++++++++++------------------------- 5 files changed, 22 insertions(+), 46 deletions(-) diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c index e378c2db73..f132033999 100644 --- a/accel/tcg/tcg-all.c +++ b/accel/tcg/tcg-all.c @@ -111,17 +111,6 @@ static int tcg_init(MachineState *ms) tcg_exec_init(s->tb_size * 1024 * 1024, s->splitwx_enabled); mttcg_enabled = s->mttcg_enabled; - - /* - * Initialize TCG regions only for softmmu. - * - * This needs to be done later for user mode, because the prologue - * generation needs to be delayed so that GUEST_BASE is already set. - */ -#ifndef CONFIG_USER_ONLY - tcg_region_init(); -#endif /* !CONFIG_USER_ONLY */ - return 0; } diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c index 1eefe6ea8d..04764626bc 100644 --- a/accel/tcg/translate-all.c +++ b/accel/tcg/translate-all.c @@ -1339,6 +1339,9 @@ void tcg_exec_init(unsigned long tb_size, int splitwx) splitwx, &error_fatal); assert(ok); + /* TODO: allocating regions is hand-in-glove with code_gen_buffer. */ + tcg_region_init(); + #if defined(CONFIG_SOFTMMU) /* There's no guest base to take into account, so go ahead and initialize the prologue now. */ diff --git a/bsd-user/main.c b/bsd-user/main.c index 9d370bc8f6..270cf2ca70 100644 --- a/bsd-user/main.c +++ b/bsd-user/main.c @@ -879,7 +879,6 @@ int main(int argc, char **argv) * the real value of GUEST_BASE into account. */ tcg_prologue_init(tcg_ctx); - tcg_region_init(); /* build Task State */ memset(ts, 0, sizeof(TaskState)); diff --git a/linux-user/main.c b/linux-user/main.c index 4dfc47ad3b..2fb3a366a6 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -868,7 +868,6 @@ int main(int argc, char **argv, char **envp) generating the prologue until now so that the prologue can take the real value of GUEST_BASE into account. */ tcg_prologue_init(tcg_ctx); - tcg_region_init(); target_cpu_copy_regs(env, regs); diff --git a/tcg/tcg.c b/tcg/tcg.c index 0dc271aac9..1e683b80e4 100644 --- a/tcg/tcg.c +++ b/tcg/tcg.c @@ -1206,32 +1206,18 @@ TranslationBlock *tcg_tb_alloc(TCGContext *s) void tcg_prologue_init(TCGContext *s) { - size_t prologue_size, total_size; - void *buf0, *buf1; + size_t prologue_size; /* Put the prologue at the beginning of code_gen_buffer. */ - buf0 = s->code_gen_buffer; - total_size = s->code_gen_buffer_size; - s->code_ptr = buf0; - s->code_buf = buf0; + tcg_region_assign(s, 0); + s->code_ptr = s->code_gen_ptr; + s->code_buf = s->code_gen_ptr; s->data_gen_ptr = NULL; - /* - * The region trees are not yet configured, but tcg_splitwx_to_rx - * needs the bounds for an assert. - */ - region.start = buf0; - region.end = buf0 + total_size; - #ifndef CONFIG_TCG_INTERPRETER - tcg_qemu_tb_exec = (tcg_prologue_fn *)tcg_splitwx_to_rx(buf0); + tcg_qemu_tb_exec = (tcg_prologue_fn *)tcg_splitwx_to_rx(s->code_ptr); #endif - /* Compute a high-water mark, at which we voluntarily flush the buffer - and start over. The size here is arbitrary, significantly larger - than we expect the code generation for any one opcode to require. */ - s->code_gen_highwater = s->code_gen_buffer + (total_size - TCG_HIGHWATER); - #ifdef TCG_TARGET_NEED_POOL_LABELS s->pool_labels = NULL; #endif @@ -1248,32 +1234,32 @@ void tcg_prologue_init(TCGContext *s) } #endif - buf1 = s->code_ptr; + prologue_size = tcg_current_code_size(s); + #ifndef CONFIG_TCG_INTERPRETER - flush_idcache_range((uintptr_t)tcg_splitwx_to_rx(buf0), (uintptr_t)buf0, - tcg_ptr_byte_diff(buf1, buf0)); + flush_idcache_range((uintptr_t)tcg_splitwx_to_rx(s->code_buf), + (uintptr_t)s->code_buf, prologue_size); #endif - /* Deduct the prologue from the buffer. */ - prologue_size = tcg_current_code_size(s); - s->code_gen_ptr = buf1; - s->code_gen_buffer = buf1; - s->code_buf = buf1; - total_size -= prologue_size; - s->code_gen_buffer_size = total_size; + /* Deduct the prologue from the first region. */ + region.start = s->code_ptr; - tcg_register_jit(tcg_splitwx_to_rx(s->code_gen_buffer), total_size); + /* Recompute boundaries of the first region. */ + tcg_region_assign(s, 0); + + tcg_register_jit(tcg_splitwx_to_rx(region.start), + region.end - region.start); #ifdef DEBUG_DISAS if (qemu_loglevel_mask(CPU_LOG_TB_OUT_ASM)) { FILE *logfile = qemu_log_lock(); qemu_log("PROLOGUE: [size=%zu]\n", prologue_size); if (s->data_gen_ptr) { - size_t code_size = s->data_gen_ptr - buf0; + size_t code_size = s->data_gen_ptr - s->code_gen_ptr; size_t data_size = prologue_size - code_size; size_t i; - log_disas(buf0, code_size); + log_disas(s->code_gen_ptr, code_size); for (i = 0; i < data_size; i += sizeof(tcg_target_ulong)) { if (sizeof(tcg_target_ulong) == 8) { @@ -1287,7 +1273,7 @@ void tcg_prologue_init(TCGContext *s) } } } else { - log_disas(buf0, prologue_size); + log_disas(s->code_gen_ptr, prologue_size); } qemu_log("\n"); qemu_log_flush();