gwj / at91sam9263 · Commits

Commit e936243acad7a657d26560d16a1cb2a505936c2d

Authored by balrog
1 parent f0b3f3ae

A branch insn must not overwrite the branch target before relocation. 

When a branch to label is translated it generates a reloc that is filled in
when the label is translated.  However, when handling an exception and
searching for the pc we abort the translation early and we sometimes
translate the branch but not the corresponding label and so no relocation
is done.  When the block is executed again the branch points to no-where.

It seems tcg/sparc/ is going to suffer from the same issue.


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4547 c046a42c-6fe2-441c-8c8c-71466251a162
Inline Side-by-side
Showing 1 changed file with 14 additions and 3 deletions
tcg/arm/tcg-target.c
  View file @e936243
... ... @@ -78,8 +78,8 @@ static void patch_reloc(uint8_t *code_ptr, int type,
78 78 tcg_abort();
79 79  
80 80 case R_ARM_PC24:
81   - *(uint32_t *) code_ptr |=
82   - ((value - ((tcg_target_long) code_ptr + 8)) >> 2) & 0xffffff;
  81 + *(uint32_t *) code_ptr |= (*(uint32_t *) code_ptr & 0xff000000) |
  82 + (((value - ((tcg_target_long) code_ptr + 8)) >> 2) & 0xffffff);
83 83 break;
84 84 }
85 85 }
... ... @@ -272,6 +272,17 @@ static inline void tcg_out_b(TCGContext *s, int cond, int32_t offset)
272 272 (((offset - 8) >> 2) & 0x00ffffff));
273 273 }
274 274  
  275 +static inline void tcg_out_b_noaddr(TCGContext *s, int cond)
  276 +{
  277 +#ifdef WORDS_BIGENDIAN
  278 + tcg_out8(s, (cond << 4) | 0x0a);
  279 + s->code_ptr += 3;
  280 +#else
  281 + s->code_ptr += 3;
  282 + tcg_out8(s, (cond << 4) | 0x0a);
  283 +#endif
  284 +}
  285 +
275 286 static inline void tcg_out_bl(TCGContext *s, int cond, int32_t offset)
276 287 {
277 288 tcg_out32(s, (cond << 28) | 0x0b000000 |
... ... @@ -734,7 +745,7 @@ static inline void tcg_out_goto_label(TCGContext *s, int cond, int label_index)
734 745 } else {
735 746 /* Probably this should be preferred even for COND_AL... */
736 747 tcg_out_reloc(s, s->code_ptr, R_ARM_PC24, label_index, 31337);
737   - tcg_out_b(s, cond, 8);
  748 + tcg_out_b_noaddr(s, cond);
738 749 }
739 750 }
740 751  
... ...