On 5/18/23 06:57, Fei Wu wrote:
+void HELPER(inc_exec_freq)(void *ptr)
+{
+ TBStatistics *stats = (TBStatistics *) ptr;
+ tcg_debug_assert(stats);
+ ++stats->executions.normal;
+}
...
+static inline void gen_tb_exec_count(TranslationBlock *tb)
+{
+ if (tb_stats_enabled(tb, TB_EXEC_STATS)) {
+ TCGv_ptr ptr = tcg_temp_new_ptr();
+ tcg_gen_movi_ptr(ptr, (intptr_t)tb->tb_stats);
+ gen_helper_inc_exec_freq(ptr);
+ }
+}
This is 3 host instructions, easily expanded inline:
--- a/accel/tcg/translator.c
+++ b/accel/tcg/translator.c
@@ -11,6 +11,7 @@
#include "qemu/error-report.h"
#include "tcg/tcg.h"
#include "tcg/tcg-op.h"
+#include "tcg/tcg-temp-internal.h"
#include "exec/exec-all.h"
#include "exec/gen-icount.h"
#include "exec/log.h"
@@ -18,6 +19,30 @@
#include "exec/plugin-gen.h"
#include "exec/replay-core.h"
+
+static void gen_tb_exec_count(TranslationBlock *tb)
+{
+ if (tb_stats_enabled(tb, TB_EXEC_STATS)) {
+ TCGv_ptr ptr = tcg_temp_ebb_new_ptr();
+
+ tcg_gen_movi_ptr(ptr, (intptr_t)&tb->tb_stats->executions.normal);
+ if (sizeof(tb->tb_stats->executions.normal) == 4) {
+ TCGv_i32 t = tcg_temp_ebb_new_i32();
+ tcg_gen_ld_i32(t, ptr, 0);
+ tcg_gen_addi_i32(t, t, 1);
+ tcg_gen_st_i32(t, ptr, 0);
+ tcg_temp_free_i32(t);
+ } else {
+ TCGv_i64 t = tcg_temp_ebb_new_i64();
+ tcg_gen_ld_i64(t, ptr, 0);
+ tcg_gen_addi_i64(t, t, 1);
+ tcg_gen_st_i64(t, ptr, 0);
+ tcg_temp_free_i64(t);
+ }
+ tcg_temp_free_ptr(ptr);
+ }
+}
+
bool translator_use_goto_tb(DisasContextBase *db, target_ulong dest)
{
/* Suppress goto_tb if requested. */
I'm not expecially keen on embedding the TBStatistics pointer directly
like this; for most hosts we will have to put this constant into the
constant pool. Whereas the pointer already exists at tb->tb_stats, and
tb is at a constant displacement prior to the code, so we already have
mechanisms for generating pc-relative addresses.
However, that's premature optimization. Let's get it working first.