From 5e866f5aeeaf7514f5ca4f9eaba41594eac22e5b Mon Sep 17 00:00:00 2001 From: Thomas Preud'homme Date: Fri, 1 Jul 2016 16:13:25 +0100 Subject: [PATCH] Fix Thumb-2 BL detection 2016-07-01 Thomas Preud'homme bfd/ * elf32-arm.c (using_thumb2_bl): New function. (arm_type_of_stub): Declare thumb2 variable together and change type to bfd_boolean. Use using_thumb2_bl () to determine whether THM_MAX_FWD_BRANCH_OFFSET or THM2_MAX_FWD_BRANCH_OFFSET should be checked for BL range. (elf32_arm_final_link_relocate): Use using_thumb2_bl () to determine the bit size of BL offset. ld/ * testsuite/ld-arm/arm-elf.exp (Thumb-2 BL): Assemble for ARMv7. (Thumb-2 BL on ARMv6-M): New testcase. * testsuite/ld-arm/thumb2-bl.d: Do not try to match testcase filename. * testsuite/ld-arm/thumb2-bl.s: Do not select architecture. --- bfd/ChangeLog | 10 ++++++++++ bfd/elf32-arm.c | 30 ++++++++++++++++++++++++------ ld/ChangeLog | 7 +++++++ ld/testsuite/ld-arm/arm-elf.exp | 5 ++++- ld/testsuite/ld-arm/thumb2-bl.d | 2 +- ld/testsuite/ld-arm/thumb2-bl.s | 1 - 6 files changed, 46 insertions(+), 9 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 90e34ac8654..adfed6f9e1f 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,13 @@ +2016-07-01 Thomas Preud'homme + + * elf32-arm.c (using_thumb2_bl): New function. + (arm_type_of_stub): Declare thumb2 variable together and change type + to bfd_boolean. Use using_thumb2_bl () to determine whether + THM_MAX_FWD_BRANCH_OFFSET or THM2_MAX_FWD_BRANCH_OFFSET should be + checked for BL range. + (elf32_arm_final_link_relocate): Use using_thumb2_bl () to determine + the bit size of BL offset. + 2016-06-29 Nick Clifton * elfnn-aarch64.c (is_aarch64_mapping_symbol): New function. diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c index 3d4a458fe46..b5e7ddb8995 100644 --- a/bfd/elf32-arm.c +++ b/bfd/elf32-arm.c @@ -3569,6 +3569,24 @@ using_thumb2 (struct elf32_arm_link_hash_table *globals) || arch == TAG_CPU_ARCH_V8M_MAIN); } +/* Determine whether Thumb-2 BL instruction is available. */ + +static bfd_boolean +using_thumb2_bl (struct elf32_arm_link_hash_table *globals) +{ + int arch = + bfd_elf_get_obj_attr_int (globals->obfd, OBJ_ATTR_PROC, Tag_CPU_arch); + + /* Force return logic to be reviewed for each new architecture. */ + BFD_ASSERT (arch <= TAG_CPU_ARCH_V8 + || arch == TAG_CPU_ARCH_V8M_BASE + || arch == TAG_CPU_ARCH_V8M_MAIN); + + /* Architecture was introduced after ARMv6T2 (eg. ARMv6-M). */ + return (arch == TAG_CPU_ARCH_V6T2 + || arch >= TAG_CPU_ARCH_V7); +} + /* Create .plt, .rel(a).plt, .got, .got.plt, .rel(a).got, .dynbss, and .rel(a).bss sections in DYNOBJ, and set up shortcuts to them in our hash table. */ @@ -3823,8 +3841,7 @@ arm_type_of_stub (struct bfd_link_info *info, bfd_signed_vma branch_offset; unsigned int r_type; struct elf32_arm_link_hash_table * globals; - int thumb2; - int thumb_only; + bfd_boolean thumb2, thumb2_bl, thumb_only; enum elf32_arm_stub_type stub_type = arm_stub_none; int use_plt = 0; enum arm_st_branch_type branch_type = *actual_branch_type; @@ -3839,8 +3856,8 @@ arm_type_of_stub (struct bfd_link_info *info, return stub_type; thumb_only = using_thumb_only (globals); - thumb2 = using_thumb2 (globals); + thumb2_bl = using_thumb2_bl (globals); /* Determine where the call point is. */ location = (input_sec->output_offset @@ -3906,10 +3923,10 @@ arm_type_of_stub (struct bfd_link_info *info, but only if this call is not through a PLT entry. Indeed, PLT stubs handle mode switching already. */ - if ((!thumb2 + if ((!thumb2_bl && (branch_offset > THM_MAX_FWD_BRANCH_OFFSET || (branch_offset < THM_MAX_BWD_BRANCH_OFFSET))) - || (thumb2 + || (thumb2_bl && (branch_offset > THM2_MAX_FWD_BRANCH_OFFSET || (branch_offset < THM2_MAX_BWD_BRANCH_OFFSET))) || (thumb2 @@ -9838,6 +9855,7 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, bfd_signed_vma signed_check; int bitsize; const int thumb2 = using_thumb2 (globals); + const int thumb2_bl = using_thumb2_bl (globals); /* A branch to an undefined weak symbol is turned into a jump to the next instruction unless a PLT entry will be created. @@ -10014,7 +10032,7 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, this relocation according to whether we're relocating for Thumb-2 or not. */ bitsize = howto->bitsize; - if (!thumb2) + if (!thumb2_bl) bitsize -= 2; reloc_signed_max = (1 << (bitsize - 1)) - 1; reloc_signed_min = ~reloc_signed_max; diff --git a/ld/ChangeLog b/ld/ChangeLog index 5f2e6cd4b00..f53a2edff5b 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,10 @@ +2016-07-01 Thomas Preud'homme + + * testsuite/ld-arm/arm-elf.exp (Thumb-2 BL): Assemble for ARMv7. + (Thumb-2 BL on ARMv6-M): New testcase. + * testsuite/ld-arm/thumb2-bl.d: Do not try to match testcase filename. + * testsuite/ld-arm/thumb2-bl.s: Do not select architecture. + 2016-07-01 Tristan Gingold * NEWS: Add marker for 2.27. diff --git a/ld/testsuite/ld-arm/arm-elf.exp b/ld/testsuite/ld-arm/arm-elf.exp index a5d4c8757cb..597bdcf4ccb 100644 --- a/ld/testsuite/ld-arm/arm-elf.exp +++ b/ld/testsuite/ld-arm/arm-elf.exp @@ -604,9 +604,12 @@ set armeabitests_nonacl { {{objdump -d fix-arm1176-off.d}} "fix-arm1176-6"} - {"Thumb-2 BL" "-Ttext 0x1000 --section-start .foo=0x1001000" "" "" {thumb2-bl.s} + {"Thumb-2 BL" "-Ttext 0x1000 --section-start .foo=0x1001000" "" "-march=armv7" {thumb2-bl.s} {{objdump -dr thumb2-bl.d}} "thumb2-bl"} + {"Thumb-2 BL on ARMv6-M" "-Ttext 0x1000 --section-start .foo=0x1001000" "" "-march=armv6-m" {thumb2-bl.s} + {{objdump -dr thumb2-bl.d}} + "thumb2-armv6m-bl"} {"Thumb-2 Interworked branch" "-T arm.ld" "" "" {thumb2-b-interwork.s} {{objdump -dr thumb2-b-interwork.d}} "thumb2-b-interwork"} diff --git a/ld/testsuite/ld-arm/thumb2-bl.d b/ld/testsuite/ld-arm/thumb2-bl.d index 298a0446a0c..8dab0c048f4 100644 --- a/ld/testsuite/ld-arm/thumb2-bl.d +++ b/ld/testsuite/ld-arm/thumb2-bl.d @@ -1,5 +1,5 @@ -.*thumb2-bl: file format elf32-.*arm.* +.*: file format elf32-.*arm.* Disassembly of section .text: diff --git a/ld/testsuite/ld-arm/thumb2-bl.s b/ld/testsuite/ld-arm/thumb2-bl.s index ddb1cd33fcb..80af8108b8f 100644 --- a/ld/testsuite/ld-arm/thumb2-bl.s +++ b/ld/testsuite/ld-arm/thumb2-bl.s @@ -1,7 +1,6 @@ @ Test to ensure that a Thumb-2 BL works with an offset that is @ not permissable for Thumb-1. - .arch armv7 .global _start .syntax unified -- 2.30.2