arm: implement additional relocations generated by gcc 4.9 at -O3

GCC 4.9 also generates R_ARM_THM_MOVW_ABS_NC and R_ARM_THM_MOVT_ABS,
as an alternative to ABS32.

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
This commit is contained in:
Leif Lindholm 2015-02-03 21:16:36 +00:00
parent 016875dd52
commit c0f529ea67
3 changed files with 59 additions and 0 deletions

View file

@ -205,6 +205,21 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,
*/
case R_ARM_V4BX:
break;
case R_ARM_THM_MOVW_ABS_NC:
case R_ARM_THM_MOVT_ABS:
{
grub_uint32_t offset;
offset = grub_arm_thm_movw_movt_get_value((grub_uint16_t *) target);
offset += sym_addr;
if (ELF_R_TYPE (rel->r_info) == R_ARM_THM_MOVT_ABS)
offset >>= 16;
else
offset &= 0xffff;
grub_arm_thm_movw_movt_set_value((grub_uint16_t *) target, offset);
}
break;
case R_ARM_THM_JUMP19:
{
/* Thumb instructions can be 16-bit aligned */

View file

@ -25,6 +25,20 @@
#include <grub/i18n.h>
#include <grub/arm/reloc.h>
static inline grub_uint32_t
thumb_get_instruction_word(grub_uint16_t *target)
{
/* Extract instruction word in alignment-safe manner */
return grub_le_to_cpu16 ((*target)) << 16 | grub_le_to_cpu16 (*(target + 1));
}
static inline void
thumb_set_instruction_word(grub_uint16_t *target, grub_uint32_t insword)
{
*target = grub_cpu_to_le16 (insword >> 16);
*(target + 1) = grub_cpu_to_le16 (insword & 0xffff);
}
/*
* R_ARM_ABS32
*
@ -214,3 +228,28 @@ grub_arm_jump24_set_offset (grub_uint32_t *target,
*target = grub_cpu_to_le32 (insword);
}
grub_uint16_t
grub_arm_thm_movw_movt_get_value (grub_uint16_t *target)
{
grub_uint32_t insword;
insword = thumb_get_instruction_word (target);
return ((insword & 0xf0000) >> 4) | ((insword & 0x04000000) >> 15) | \
((insword & 0x7000) >> 4) | (insword & 0xff);
}
void
grub_arm_thm_movw_movt_set_value (grub_uint16_t *target, grub_uint16_t value)
{
grub_uint32_t insword;
insword = thumb_get_instruction_word (target);
insword &= 0xfbf08f00;
insword |= ((value & 0xf000) << 4) | ((value & 0x0800) << 15) | \
((value & 0x0700) << 4) | (value & 0xff);
thumb_set_instruction_word (target, insword);
}

View file

@ -43,4 +43,9 @@ void
grub_arm_jump24_set_offset (grub_uint32_t *target,
grub_int32_t offset);
grub_uint16_t
grub_arm_thm_movw_movt_get_value (grub_uint16_t *target);
void
grub_arm_thm_movw_movt_set_value (grub_uint16_t *target, grub_uint16_t value);
#endif