gwj / at91sam9263 · Commits

Commit 2ba1eeb62c29d23238b95dc7e9ade3444b49f0a1

Authored by pbrook
1 parent 41df8411

Fix TCG relocation bug (exposed by fault after brcond op). Add FIXME for 

annother potential bug.


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3968 c046a42c-6fe2-441c-8c8c-71466251a162
Inline Side-by-side
Showing 3 changed files with 24 additions and 21 deletions
tcg/tcg.c
  View file @2ba1eeb
... ... @@ -97,6 +97,9 @@ void tcg_out_reloc(TCGContext *s, uint8_t *code_ptr, int type,
97 97  
98 98 l = &s->labels[label_index];
99 99 if (l->has_value) {
  100 + /* FIXME: This is wrong. We can not resolve the relocation
  101 + immediately because the caller has not yet written the
  102 + initial value. */
100 103 patch_reloc(code_ptr, type, l->u.value + addend);
101 104 } else {
102 105 /* add a new relocation entry */
... ... @@ -1649,8 +1652,7 @@ void dump_op_count(void)
1649 1652  
1650 1653  
1651 1654 static inline int tcg_gen_code_common(TCGContext *s, uint8_t *gen_code_buf,
1652   - int do_search_pc,
1653   - const uint8_t *searched_pc)
  1655 + long search_pc)
1654 1656 {
1655 1657 int opc, op_index, macro_op_index;
1656 1658 const TCGOpDef *def;
... ... @@ -1754,7 +1756,7 @@ static inline int tcg_gen_code_common(TCGContext *s, uint8_t *gen_code_buf,
1754 1756 }
1755 1757 #endif
1756 1758 tcg_reg_alloc_bb_end(s);
1757   - if (do_search_pc) {
  1759 + if (search_pc >= 0) {
1758 1760 s->code_ptr += def->copy_size;
1759 1761 args += def->nb_args;
1760 1762 } else {
... ... @@ -1771,13 +1773,11 @@ static inline int tcg_gen_code_common(TCGContext *s, uint8_t *gen_code_buf,
1771 1773 }
1772 1774 args += def->nb_args;
1773 1775 next: ;
1774   - if (do_search_pc) {
1775   - if (searched_pc < s->code_ptr) {
1776   - if (macro_op_index >= 0)
1777   - return macro_op_index;
1778   - else
1779   - return op_index;
1780   - }
  1776 + if (search_pc >= 0 && search_pc < s->code_ptr - gen_code_buf) {
  1777 + if (macro_op_index >= 0)
  1778 + return macro_op_index;
  1779 + else
  1780 + return op_index;
1781 1781 }
1782 1782 op_index++;
1783 1783 #ifndef NDEBUG
... ... @@ -1802,7 +1802,7 @@ int dyngen_code(TCGContext *s, uint8_t *gen_code_buf)
1802 1802 }
1803 1803 #endif
1804 1804  
1805   - tcg_gen_code_common(s, gen_code_buf, 0, NULL);
  1805 + tcg_gen_code_common(s, gen_code_buf, -1);
1806 1806  
1807 1807 /* flush instruction cache */
1808 1808 flush_icache_range((unsigned long)gen_code_buf,
... ... @@ -1810,11 +1810,16 @@ int dyngen_code(TCGContext *s, uint8_t *gen_code_buf)
1810 1810 return s->code_ptr - gen_code_buf;
1811 1811 }
1812 1812  
1813   -/* return the index of the micro operation such as the pc after is <
1814   - search_pc. Note: gen_code_buf is accessed during the operation, but
1815   - its content should not be modified. Return -1 if not found. */
1816   -int dyngen_code_search_pc(TCGContext *s, uint8_t *gen_code_buf,
1817   - const uint8_t *searched_pc)
  1813 +static uint8_t *dummy_code_buf;
  1814 +
  1815 +/* Return the index of the micro operation such as the pc after is <
  1816 + offset bytes from the start of the TB.
  1817 + We have to use a dummy code buffer here to avoid clobbering the
  1818 + oringinal code. Because we terminate code generation part way through
  1819 + we can end up with unresolved relocations. Return -1 if not found. */
  1820 +int dyngen_code_search_pc(TCGContext *s, long offset)
1818 1821 {
1819   - return tcg_gen_code_common(s, gen_code_buf, 1, searched_pc);
  1822 + if (!dummy_code_buf)
  1823 + dummy_code_buf = qemu_malloc(code_gen_max_block_size());
  1824 + return tcg_gen_code_common(s, dummy_code_buf, offset);
1820 1825 }
... ...
tcg/tcg.h
  View file @2ba1eeb
... ... @@ -257,8 +257,7 @@ void tcg_context_init(TCGContext *s);
257 257 void tcg_func_start(TCGContext *s);
258 258  
259 259 int dyngen_code(TCGContext *s, uint8_t *gen_code_buf);
260   -int dyngen_code_search_pc(TCGContext *s, uint8_t *gen_code_buf,
261   - const uint8_t *searched_pc);
  260 +int dyngen_code_search_pc(TCGContext *s, long offset);
262 261  
263 262 void tcg_set_frame(TCGContext *s, int reg,
264 263 tcg_target_long start, tcg_target_long size);
... ...
translate-all.c
  View file @2ba1eeb
... ... @@ -187,8 +187,7 @@ int cpu_restore_state(TranslationBlock *tb,
187 187 s->tb_jmp_offset = NULL;
188 188 s->tb_next = tb->tb_next;
189 189 #endif
190   - j = dyngen_code_search_pc(s, (uint8_t *)tc_ptr,
191   - (void *)searched_pc);
  190 + j = dyngen_code_search_pc(s, searched_pc - tc_ptr);
192 191 if (j < 0)
193 192 return -1;
194 193 /* now find start of instruction before */
... ...