>From cdc7b3631fd78bd2e31d2823f7543e2a56681149 Mon Sep 17 00:00:00 2001
From: Richard Henderson <address@hidden>
Date: Fri, 22 Apr 2016 11:28:52 -0700
Subject: translate-all: Add hashtable accounting to info jit

Dump hash table occupancy numbers with "info jit".

Signed-off-by: Richard Henderson <address@hidden>

diff --git a/translate-all.c b/translate-all.c
index 1a8f68b..ed296d5 100644
--- a/translate-all.c
+++ b/translate-all.c
@@ -1671,39 +1671,55 @@ void tb_flush_jmp_cache(CPUState *cpu, target_ulong addr)
 
 void dump_exec_info(FILE *f, fprintf_function cpu_fprintf)
 {
-    int i, target_code_size, max_target_code_size;
-    int direct_jmp_count, direct_jmp2_count, cross_page;
+    size_t target_code_size, max_target_code_size;
+    unsigned direct_jmp_count, direct_jmp2_count, cross_page;
+    unsigned used_buckets, max_chain, hash_tbs;
     TranslationBlock *tb;
+    int i;
 
     target_code_size = 0;
     max_target_code_size = 0;
     cross_page = 0;
     direct_jmp_count = 0;
     direct_jmp2_count = 0;
-    for (i = 0; i < tcg_ctx.tb_ctx.nb_tbs; i++) {
-        tb = &tcg_ctx.tb_ctx.tbs[i];
-        target_code_size += tb->size;
-        if (tb->size > max_target_code_size) {
-            max_target_code_size = tb->size;
-        }
-        if (tb->page_addr[1] != -1) {
-            cross_page++;
-        }
-        if (tb->tb_next_offset[0] != 0xffff) {
-            direct_jmp_count++;
-            if (tb->tb_next_offset[1] != 0xffff) {
-                direct_jmp2_count++;
+    used_buckets = 0;
+    hash_tbs = 0;
+    max_chain = 0;
+
+    for (i = 0; i < CODE_GEN_PHYS_HASH_SIZE; i++) {
+        if (tcg_ctx.tb_ctx.tb_phys_hash[i]) {
+            unsigned this_chain = 0;
+            for (tb = tcg_ctx.tb_ctx.tb_phys_hash[i]; tb != NULL;
+                 tb = tb->phys_hash_next) {
+                this_chain++;
+                hash_tbs++;
+                target_code_size += tb->size;
+                if (tb->page_addr[1] != -1) {
+                    cross_page++;
+                }
+                if (tb->tb_next_offset[0] != 0xffff) {
+                    direct_jmp_count++;
+                    if (tb->tb_next_offset[1] != 0xffff) {
+                        direct_jmp2_count++;
+                    }
+                }
             }
+            if (this_chain > max_chain) {
+                max_chain = this_chain;
+            }
+            used_buckets++;
         }
     }
-    /* XXX: avoid using doubles ? */
+    assert(hash_tbs ==
+           tcg_ctx.tb_ctx.nb_tbs - tcg_ctx.tb_ctx.tb_phys_invalidate_count);
+
     cpu_fprintf(f, "Translation buffer state:\n");
     cpu_fprintf(f, "gen code size       %td/%zd\n",
                 tcg_ctx.code_gen_ptr - tcg_ctx.code_gen_buffer,
                 tcg_ctx.code_gen_highwater - tcg_ctx.code_gen_buffer);
     cpu_fprintf(f, "TB count            %d/%d\n",
             tcg_ctx.tb_ctx.nb_tbs, tcg_ctx.code_gen_max_blocks);
-    cpu_fprintf(f, "TB avg target size  %d max=%d bytes\n",
+    cpu_fprintf(f, "TB avg target size  %zd max=%zd bytes\n",
             tcg_ctx.tb_ctx.nb_tbs ? target_code_size /
                     tcg_ctx.tb_ctx.nb_tbs : 0,
             max_target_code_size);
@@ -1717,13 +1733,18 @@ void dump_exec_info(FILE *f, fprintf_function cpu_fprintf)
     cpu_fprintf(f, "cross page TB count %d (%d%%)\n", cross_page,
             tcg_ctx.tb_ctx.nb_tbs ? (cross_page * 100) /
                                     tcg_ctx.tb_ctx.nb_tbs : 0);
-    cpu_fprintf(f, "direct jump count   %d (%d%%) (2 jumps=%d %d%%)\n",
+    cpu_fprintf(f, "direct jump count   %u (%u%%) (2 jumps=%u %u%%)\n",
                 direct_jmp_count,
                 tcg_ctx.tb_ctx.nb_tbs ? (direct_jmp_count * 100) /
                         tcg_ctx.tb_ctx.nb_tbs : 0,
                 direct_jmp2_count,
                 tcg_ctx.tb_ctx.nb_tbs ? (direct_jmp2_count * 100) /
                         tcg_ctx.tb_ctx.nb_tbs : 0);
+    cpu_fprintf(f, "TB hash buckets     %u/%d\n",
+                used_buckets, CODE_GEN_PHYS_HASH_SIZE);
+    cpu_fprintf(f, "TB hash avg chain   %0.3f max=%u\n",
+                used_buckets ? (double)hash_tbs / used_buckets : 0.0,
+                max_chain);
     cpu_fprintf(f, "\nStatistics:\n");
     cpu_fprintf(f, "TB flush count      %d\n", tcg_ctx.tb_ctx.tb_flush_count);
     cpu_fprintf(f, "TB invalidate count %d\n",