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, _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 -
