From c3e95ec34ee0be3ac74e57bd9987e1fce176952c Mon Sep 17 00:00:00 2001
From: Nguyen Anh Quynh <aquynh@gmail.com>
Date: Tue, 25 Aug 2015 14:50:55 +0800
Subject: [PATCH] x86: do not generate basic-block callback when translation is
 broken in the middle due to full cache

---
 include/uc_priv.h            | 2 ++
 qemu/target-i386/translate.c | 8 +++++++-
 uc.c                         | 1 +
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/include/uc_priv.h b/include/uc_priv.h
index 1494cc65..2703627c 100644
--- a/include/uc_priv.h
+++ b/include/uc_priv.h
@@ -163,6 +163,8 @@ struct uc_struct {
     uint64_t addr_end;  // address where emulation stops (@end param of uc_emu_start())
 
     int thumb;  // thumb mode for ARM
+    // full TCG cache leads to middle-block break in the last translation?
+    bool block_full;
 };
 
 #include "qemu_macro.h"
diff --git a/qemu/target-i386/translate.c b/qemu/target-i386/translate.c
index 15b941c4..7ce37ef8 100644
--- a/qemu/target-i386/translate.c
+++ b/qemu/target-i386/translate.c
@@ -8256,6 +8256,7 @@ static inline void gen_intermediate_code_internal(uint8_t *gen_opc_cc_op,
     target_ulong cs_base;
     int num_insns;
     int max_insns;
+    bool block_full = false;
 
     /* generate intermediate code */
     pc_start = tb->pc;
@@ -8349,7 +8350,9 @@ static inline void gen_intermediate_code_internal(uint8_t *gen_opc_cc_op,
         max_insns = CF_COUNT_MASK;
 
     // Unicorn: trace this block on request
-    if (env->uc->hook_block) {
+    // Only hook this block if it is not broken from previous translation due to
+    // full translation cache
+    if (env->uc->hook_block && !env->uc->block_full) {
         struct hook_struct *trace = hook_find((uch)env->uc, UC_HOOK_BLOCK, pc_start);
         if (trace) {
             env->uc->block_addr = pc_start;
@@ -8407,6 +8410,7 @@ static inline void gen_intermediate_code_internal(uint8_t *gen_opc_cc_op,
             num_insns >= max_insns) {
             gen_jmp_im(dc, pc_ptr - dc->cs_base);
             gen_eob(dc);
+            block_full = true;
             break;
         }
     }
@@ -8427,6 +8431,8 @@ done_generating:
         tb->size = pc_ptr - pc_start;
         // tb->icount = num_insns;
     }
+
+    env->uc->block_full = block_full;
 }
 
 void gen_intermediate_code(CPUX86State *env, TranslationBlock *tb)
diff --git a/uc.c b/uc.c
index 2011c693..65179095 100644
--- a/uc.c
+++ b/uc.c
@@ -414,6 +414,7 @@ uc_err uc_emu_start(uch handle, uint64_t begin, uint64_t until, uint64_t timeout
     uc->emu_counter = 0;
     uc->stop_request = false;
     uc->invalid_error = UC_ERR_OK;
+    uc->block_full = false;
 
     switch(uc->arch) {
         default: