diff options
| author | Viorel Preoteasa <viorel.preoteasa@gmail.com> | 2022-03-18 15:32:28 +0000 |
|---|---|---|
| committer | Nick Clifton <nickc@redhat.com> | 2022-03-18 15:32:28 +0000 |
| commit | a747a286b9331adfba85a508beddaef47ea1a1c2 (patch) | |
| tree | 1bcd10aa0944fad7fbb3cf03acea7db86e01f0ad /bfd/elf32-arm.c | |
| parent | c4d0963383ad8ca0f0bf63c857b9462efdacff7c (diff) | |
Fix ld-arm bug in encoding of blx calls jumping from thumb to arm instructions
PR 28924
* elf32-arm.c (THM_MAX_FWD_BRANCH_OFFSET): Fix definition.
(THM2_MAX_FWD_BRANCH_OFFSET): Likewise.
Diffstat (limited to 'bfd/elf32-arm.c')
| -rw-r--r-- | bfd/elf32-arm.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c index 616efe60ad..5b8f5e5a0e 100644 --- a/bfd/elf32-arm.c +++ b/bfd/elf32-arm.c @@ -2536,11 +2536,23 @@ static const bfd_vma elf32_arm_nacl_plt_entry [] = 0xea000000, /* b .Lplt_tail */ }; +/* PR 28924: + There was a bug due to too high values of THM_MAX_FWD_BRANCH_OFFSET and + THM2_MAX_FWD_BRANCH_OFFSET. The first macro concerns the case when Thumb-2 + is not available, and second macro when Thumb-2 is available. Among other + things, they affect the range of branches represented as BLX instructions + in Encoding T2 defined in Section A8.8.25 of the ARM Architecture + Reference Manual ARMv7-A and ARMv7-R edition issue C.d. Such branches are + specified there to have a maximum forward offset that is a multiple of 4. + Previously, the respective values defined here were multiples of 2 but not + 4 and they are included in comments for reference. */ #define ARM_MAX_FWD_BRANCH_OFFSET ((((1 << 23) - 1) << 2) + 8) -#define ARM_MAX_BWD_BRANCH_OFFSET ((-((1 << 23) << 2)) + 8) -#define THM_MAX_FWD_BRANCH_OFFSET ((1 << 22) -2 + 4) +#define ARM_MAX_BWD_BRANCH_OFFSET ((-((1 << 23) << 2)) + 8) +#define THM_MAX_FWD_BRANCH_OFFSET ((1 << 22) - 4 + 4) +/* #def THM_MAX_FWD_BRANCH_OFFSET ((1 << 22) - 2 + 4) */ #define THM_MAX_BWD_BRANCH_OFFSET (-(1 << 22) + 4) -#define THM2_MAX_FWD_BRANCH_OFFSET (((1 << 24) - 2) + 4) +#define THM2_MAX_FWD_BRANCH_OFFSET (((1 << 24) - 4) + 4) +/* #def THM2_MAX_FWD_BRANCH_OFFSET (((1 << 24) - 2) + 4) */ #define THM2_MAX_BWD_BRANCH_OFFSET (-(1 << 24) + 4) #define THM2_MAX_FWD_COND_BRANCH_OFFSET (((1 << 20) -2) + 4) #define THM2_MAX_BWD_COND_BRANCH_OFFSET (-(1 << 20) + 4) |