find_trampoline_seg takes noticeable time when assembling source with
many sections. Cache the result of the most recent search and check it
first. No functional changes.
gas/
2017-11-27 Max Filippov <jcmvbkbc@gmail.com>
* config/tc-xtensa.c (find_trampoline_seg): Add static variable
that caches the result of the most recent search.
There is a recurring pattern in assembly files generated by a compiler
where a lot of jumps in a function are going to the same place. When
these jumps are relaxed with trampolines the assembler generates a
separate jump thread from each source.
Create an index of trampoline jump targets for each segment and see if a
jump being relaxed goes to a location from that index, in which case
replace its target with a location of existing trampoline jump that
results in the shortest path to the original target.
gas/
2017-11-27 Max Filippov <jcmvbkbc@gmail.com>
* config/tc-xtensa.c (trampoline_chain_entry, trampoline_chain)
(trampoline_chain_index): New structures.
(trampoline_index): Add chain_index field.
(xg_order_trampoline_chain_entry, xg_sort_trampoline_chain)
(xg_find_chain_entry, xg_get_best_chain_entry)
(xg_order_trampoline_chain, xg_get_trampoline_chain)
(xg_find_best_eq_target, xg_add_location_to_chain)
(xg_create_trampoline_chain, xg_get_single_symbol_slot): New
functions.
(xg_relax_fixups): Call xg_find_best_eq_target to adjust jump
target to point to an existing jump. Call
xg_create_trampoline_chain to create new jump target. Call
xg_add_location_to_chain to add newly created trampoline jump
to the corresponding chain.
(add_jump_to_trampoline): Extract loop searching for a single
slot with a symbol into a separate function, replace that code
with a call to that function.
(relax_frag_immed): Call xg_find_best_eq_target to adjust jump
target to point to an existing jump.
* testsuite/gas/xtensa/all.exp: Add trampoline-2 test.
* testsuite/gas/xtensa/trampoline.d: Adjust absolute addresses
as many duplicate trampoline chains are now coalesced.
* testsuite/gas/xtensa/trampoline.s: Add _nop so that objdump
stays in sync with instruction stream.
* testsuite/gas/xtensa/trampoline-2.l: New test result file.
* testsuite/gas/xtensa/trampoline-2.s: New test source file.
There's almost exact copy of the trampoline placement code in the
search_trampolines function that is used for jumps generated for relaxed
branch instructions. Get rid of the duplication and reuse
xg_find_best_trampoline function for that.
gas/
2017-11-27 Max Filippov <jcmvbkbc@gmail.com>
* config/tc-xtensa.c (search_trampolines, get_best_trampoline):
Remove definitions.
(xg_find_best_trampoline_for_tinsn): New function.
(relax_frag_immed): Replace call to get_best_trampoline with a
call to xg_find_best_trampoline_for_tinsn.
* testsuite/gas/xtensa/trampoline.d: Adjust absolute addresses
as the placement of trampolines for relaxed branches has been
changed.
Replace linked list of trampoline frags with an ordered array, so that
instead of indexing fixups trampolines could be indexed. Keep each array
in the trampoline_seg structure, so there's no need to rebuild it for
every new processed segment. Don't run relaxation for each trampoline
frag, instead run it for each fixup in the current segment that needs
relaxation at the beginning of each relaxation pass. This way the
complexity of this process drops from about O(n^2 * m) to about
O(log n * m), where n is the number of trampoline frags and m is the
number of fixups that need relaxation in the segment.
gas/
2017-11-27 Max Filippov <jcmvbkbc@gmail.com>
* config/tc-xtensa.c (trampoline_index): New structure.
(trampoline_seg): Replace trampoline list with trampoline index.
(xg_find_trampoline, xg_add_trampoline_to_index)
(xg_remove_trampoline_from_index, xg_add_trampoline_to_seg)
(xg_is_trampoline_frag_full, xg_get_fulcrum)
(xg_find_best_trampoline, xg_relax_fixup, xg_relax_fixups)
(xg_is_relaxable_fixup): New functions.
(J_MARGIN): New macro.
(xtensa_create_trampoline_frag): Use xg_add_trampoline_to_seg
instead of open-coded addition to the linked list.
(dump_trampolines): Iterate through the trampoline_seg::index.
(cached_fixupS, cached_fixup, fixup_cacheS, fixup_cache)
(fixup_order, xtensa_make_cached_fixup)
(xtensa_realloc_fixup_cache, xtensa_cache_relaxable_fixups)
(xtensa_find_first_cached_fixup, xtensa_delete_cached_fixup)
(xtensa_add_cached_fixup, check_and_update_trampolines): Remove
definitions.
(xg_relax_trampoline): Extract logic into separate functions,
replace body with a call to xg_relax_fixups.
(search_trampolines): Replace search in linked list with search
in index. Change data type of address-tracking variables from
int to offsetT. Replace abs with labs.
(xg_append_jump): Finish the trampoline frag if it's full.
(add_jump_to_trampoline): Remove trampoline frag from the index
if the frag is full.
* config/tc-xtensa.h (xtensa_frag_type): Remove next_trampoline.
* testsuite/gas/xtensa/trampoline.d: Adjust absolute addresses
as the placement of trampolines has slightly changed.
* testsuite/gas/xtensa/trampoline.s: Add _nop so that objdump
stays in sync with instruction stream.
The split between fragS and trampoline_frag doesn't save much space, but
makes trampolines management much more awkward. Merge trampoline_frag
data into the xtensa_frag_type, which is a part of fragS. No functional
changes.
gas/
2017-11-27 Max Filippov <jcmvbkbc@gmail.com>
* config/tc-xtensa.c (init_trampoline_frag): Replace pointer to
struct trampoline_frag parameter with pointer to fragS.
(xg_append_jump): Remove jump_around parameter.
(struct trampoline_frag): Remove.
(struct trampoline_seg): Change type of trampoline_list from
struct trampoline_frag to fragS.
(xtensa_create_trampoline_frag): Don't allocate struct
trampoline_frag. Initialize new fragS::tc_frag_data fields.
(dump_trampolines, xg_relax_trampoline, search_trampolines)
(get_best_trampoline, init_trampoline_frag)
(add_jump_to_trampoline, relax_frag_immed): Replace pointer to
struct trampoline_frag with a pointer to fragS.
(xg_append_jump): Remove jump_around parameter, use
fragS::tc_frag_data.jump_around_fix instead.
(xg_relax_trampoline, init_trampoline_frag)
(add_jump_to_trampoline): Don't pass jump_around parameter to
xg_append_jump.
* config/tc-xtensa.h (struct xtensa_frag_type): Add new fields:
needs_jump_around, next_trampoline and jump_around_fix.
xtensa_create_trampoline_frag has opencoded fragment equivalent to
find_trampoline_seg. Drop the fragment and use find_trampoline_seg
instead. No functional changes.
gas/
2017-11-27 Max Filippov <jcmvbkbc@gmail.com>
* config/tc-xtensa.c (find_trampoline_seg): Move above the first
use.
(xtensa_create_trampoline_frag): Replace trampoline seg search
code with a call to find_trampoline_seg.
init_trampoline_frag, add_jump_to_trampoline and xg_relax_trampoline add
a jump to the end of a trampoline frag. Extract it into a separate
funciton and use it in all these places. No functional changes.
gas/
2017-11-27 Max Filippov <jcmvbkbc@gmail.com>
* config/tc-xtensa.c (xg_append_jump): New function.
(xg_relax_trampoline, init_trampoline_frag)
(add_jump_to_trampoline): Replace trampoline jump assembling
code with a call to xg_append_jump.
To make measurement and changes easier extract trampoline relaxation
function. No functional changes.
gas/
2017-11-27 Max Filippov <jcmvbkbc@gmail.com>
* config/tc-xtensa.c (xg_relax_trampoline): New function.
(xtensa_relax_frag): Replace trampoline relaxation code with a
call to xg_relax_trampoline.
For one the register type used for masking should be validated. And then
we shouldn't accept input producing encodings which will #UD when
executed, as is the case when EVEX.Z is set while EVEX.AAA is zero.
Despite EVEX encodings not being available in real and VM86 modes,
16-bit addressing still needs to be handled properly for 16-bit
protected mode as well as 16-bit addressing in 32-bit mode. Neither
should displacements be dropped silently by the assembler, nor should
the disassembler fail to correctly scale 8-bit displacements.
Except for %eip-relative addressing, where we don't have a suitable
relocation type silently wrapping at the 4G boundary, consistently
force use of R_X86_64_32 (in ELF terms) instead of its sign-extending
counterpart. This wasn't right in case there was no base register in
the addressing expression.
Multiple errors are more confusing than helpful, as the more generic
one often implies a sufficiently different adjustment than would
actually be needed to fix the code. Additionally it makes it more
cumbersome to add missing error checks, as the testsuite then needs
extra updating.
* as.c: Include write.h.
(common_emul_init): Use FAKE_LABEL_NAME.
* ecoff.c (add_file, ecoff_directive_end, ecoff_directive_loc):
Likewise.
(ecoff_build_symbols): Use FAKE_LABEL_CHAR.
* expr.c (get_symbol_name): Use FAKE_LABEL_CHAR. Accept only if
input_from_string is TRUE.
* read.c (input_from_string): New.
(read_symbol_name): Use FAKE_LABEL_CHAR. Accept only if
input_from_string is TRUE.
(temp_ilp): Set input_from_string to TRUE.
(restore_ilp): Set input_from_string to FALSE.
* read.h (input_from_string): Declare.
* symbols.c: Include write.h
(S_IS_LOCAL): Check for FAKE_LABEL_CHAR.
(symbol_relc_make_sym): Fix comment refering to default fake label
string.
* write.h (FAKE_LABEL_CHAR): New.
* config/tc-riscv.h (FAKE_LABEL_CHAR): Define.
* testsuite/gas/all/err-fakelabel.s: New.
Uses of reg_expected_msgs rely on each arm_reg_type enumerator to have a
message entry in the same order as the enumerator declaration. This is
not clearly stated in the definition of both the arm_reg_type enum and
the reg_expected_msgs. Worse, there is nothing to ensure both are kept
in sync.
As an attempt towards this, this patch uses C99 array designators to
ensure that each message is associated with the right arm_reg_type. A
comment is also added near the definition of arm_reg_type to point to
the reg_expected_msgs array. Finally, the array is synced with
arm_reg_type by adding the missing error message for REG_TYPE_RNB.
2017-11-22 Thomas Preud'homme <thomas.preudhomme@arm.com>
gas/
* config/tc-arm.c (arm_reg_type): Comment on the link with
reg_expected_msgs.
(reg_expected_msgs): Initialize using array designators with
arm_reg_type index.
This patch separates the new FP16 instructions backported from Armv8.4-a to Armv8.2-a
into a new flag order to distinguish them from the rest of the already existing optional
FP16 instructions in Armv8.2-a.
The new flag "+fp16fml" is available from Armv8.2-a and implies +fp16 and is mandatory on
Armv8.4-a.
gas/
* config/tc-aarch64.c (fp16fml): New.
* doc/c-aarch64.texi (fp16fml): New.
* testsuite/gas/aarch64/armv8_2-a-crypto-fp16.d (fp16): Make fp16fml.
* testsuite/gas/aarch64/armv8_3-a-crypto-fp16.d (fp16): Make fp16fml.
include/
* opcode/aarch64.h: (AARCH64_FEATURE_F16_FML): New.
(AARCH64_ARCH_V8_4): Enable AARCH64_FEATURE_F16_FML by default.
opcodes/
* aarch64-tbl.h (aarch64_feature_fp_16_v8_2): Require AARCH64_FEATURE_F16_FML
and AARCH64_FEATURE_F16.
The new flag "+fp16fml" is available from Armv8.2-a and implies +fp16 and is mandatory
from Armv8.4-a.
gas/
* config/tc-arm.c (arm_ext_fp16_fml, fp16fml): New.
(do_neon_fmac_maybe_scalar_long): Use arm_ext_fp16_fml.
* doc/c-arm.texi (fp16, fp16fml): New.
* testsuite/gas/arm/armv8_2-a-fp16.d (fp16): Make fp16fml.
* testsuite/gas/arm/armv8_3-a-fp16.d (fp16): Make fp16fml.
* testsuite/gas/arm/armv8_2-a-fp16-illegal.d (fp16): Make fp16fml.
* testsuite/gas/arm/armv8_2-a-fp16-thumb2.d (fp16): Make fp16fml.
include/
* opcode/arm.h: (ARM_EXT2_FP16_FML): New.
(ARM_AEXT2_V8_4A): Add ARM_EXT2_FP16_FML.
... rather than silently dropping it altogether.
i386_finalize_displacement() expects baseindex to already be set, so
the respective statement needs to be moved up. This then also allows a
subsequent conditional to be simplified.
For this to not regress on 32-bit addressing, break out address size
guessing from i386_index_check(), invoking the new function earlier so
that i386_finalize_displacement() has i.prefix[ADDR_PREFIX] available.
i386_addressing_mode () in turn needs i.base_reg / i.index_reg set
earlier.
The new options are:
+aes: Enables the AES instructions of Armv8-a,
enabled by default with +crypto.
+sha2: Enables the SHA1 and SHA2 instructions of Armv8-a,
enabled by default with +crypto.
These options have been turned on by default when +crypto
is used, as such no breakage is expected.
The reason for the split is because with the introduction of Armv8.4-a
the implementation of AES has explicitly been made independent of the
implementation of the other crypto extensions. Backporting the split does
not break any of the previous requirements and so is safe to do.
gas * config/tc-aarch64.c
(aarch64_features): Include AES and SHA2 in CRYPTO.
Add SHA2 and AES.
include * opcode/aarch64.h:
(AARCH64_FEATURE_SHA2, AARCH64_FEATURE_AES): New.
opcodes * aarch64-tbl.h (aarch64_feature_crypto): Add AES and SHA2.
(aarch64_feature_sha2, aarch64_feature_aes): New.
(SHA2, AES): New.
(AES_INSN, SHA2_INSN): New.
(pmull, pmull2, aese, aesd, aesmc, aesimc): Change to AES_INS.
(sha1h, sha1su1, sha256su0, sha1c, sha1p,
sha1m, sha1su0, sha256h, sha256h2, sha256su1):
Change to SHA2_INS.
gas * config/tc-arm.c (arm_extensions):
(arm_archs): New entry for "armv8.4-a".
Add FPU_ARCH_DOTPROD_NEON_VFP_ARMV8.
(arm_ext_v8_2): New variable.
(enum arm_reg_type): New enumeration REG_TYPE_NSD.
(reg_expected_msgs): New entry for REG_TYPE_NSD.
(parse_typed_reg_or_scalar): Handle REG_TYPE_NSD.
(parse_scalar): Support REG_TYPE_VFS.
(enum operand_parse_code): New enumerations OP_RNSD and OP_RNSD_RNSC.
(parse_operands): Handle OP_RNSD and OP_RNSD_RNSC.
(NEON_SHAPE_DEF): New entries for DHH and DHS.
(neon_scalar_for_fmac_fp16_long): New function to generate Rm encoding
for new FP16 instructions in ARMv8.2-A.
(do_neon_fmac_maybe_scalar_long): New function to encode new FP16
instructions in ARMv8.2-A.
(do_neon_vfmal): Wrapper function for vfmal.
(do_neon_vfmsl): Wrapper function for vfmsl.
(insns): New entries for vfmal and vfmsl.
* doc/c-arm.texi (-march): Document "armv8.4-a".
* testsuite/gas/arm/dotprod-mandatory.d: New test.
* testsuite/gas/arm/armv8_2-a-fp16.s: New test source.
* testsuite/gas/arm/armv8_2-a-fp16-illegal.s: New test source.
* testsuite/gas/arm/armv8_2-a-fp16.d: New test.
* testsuite/gas/arm/armv8_3-a-fp16.d: New test.
* testsuite/gas/arm/armv8_4-a-fp16.d: New test.
* testsuite/gas/arm/armv8_2-a-fp16-thumb2.d: New test.
* testsuite/gas/arm/armv8_2-a-fp16-illegal.d: New test.
* testsuite/gas/arm/armv8_2-a-fp16-illegal.l: New error file.
opcodes * arm-dis.c (coprocessor_opcodes): New entries for ARMv8.2-A new
FP16 instructions, including vfmal.f16 and vfmsl.f16.
include * opcode/arm.h (ARM_AEXT2_V8_4A): Include Dot Product feature.
(ARM_EXT2_V8_4A): New macro.
(ARM_AEXT2_V8_4A): Likewise.
(ARM_ARCH_V8_4A): Likewise.
This fixes some EH failures for the medany code model in the g++ testsuite.
The problem is that the assembler is computing some values in the eh_frame
section as constants, that instead should have had relocs to be resolved by
the linker. This happens in output_cfi_insn in the DW_CFA_advance_loc case
where it compares label frags and immediately simplifies if they are the
same. We can fix that by forcing a new frag after every instruction
that the linker can reduce in size. I've also added a testcase to verify
the fix. This was tested with binutils make check, and gcc/g++ make checks on
qemu for medlow and medany code models.
gas/
* config/tc-riscv.c (append_insn): Call frag_wane and frag_new at
end for linker optimizable relocs.
* testsuite/gas/riscv/eh-relocs.d: New.
* testsuite/gas/riscv/eh-relocs.s: New.
* testsuite/gas/riscv/riscv.exp: Run eh-relocs test.
The RISC-V privileged ISA changed the name of sptbr (Supervisor Page
Table Base Register) to satp (Supervisor Address Translation and
Protection) to reflect the fact it could be used for more than just
paging. This patch adds an alias, as they're the same register.
include/ChangeLog
2017-11-06 Palmer Dabbelt <palmer@dabbelt.com>
* opcode/riscv-opc.h (sptbr): Rename to satp.
(CSR_SPTBR): Rename to CSR_SATP.
(sptbr): Alias to CSR_SATP.
gas/ChangeLog
2017-11-06 Palmer Dabbelt <palmer@dabbelt.com>
* testsuite/gas/riscv/satp.d: New test.
testsuite/gas/riscv/satp.s: Likewise.
testsuite/gas/riscv/riscv.exp: Likewise.
config/tc-riscv.c (md_begin): Handle CSR aliases.
gas * config/tc-arm.c (arm_cpus):
Change FPU_ARCH_CRYPTO_NEON_VFP_ARMV8
into FPU_ARCH_CRYPTO_NEON_VFP_ARMV8_DOTPROD.
include * opcode/arm.h (FPU_ARCH_CRYPTO_NEON_VFP_ARMV8_DOTPROD):
New macro.
This adds an option for the Qualcomm saphira core, the corresponding
gcc patch is here:
https://gcc.gnu.org/ml/gcc-patches/2017-10/msg02055.html
This was tested with an aarch64 build and make check and also by
building and running SPEC2006.
gas/
* config/tc-aarch64.c (aarch64_cpus): Add saphira.
* doc/c-aarch64.texi: Likewise.
A few coprocessor instructions introduced in ARMv2 are currently
accepted by GAS when targeting ARMv1 due to a typo in the code. This
patch fixes the issue and introduce a more fine grained testing for
coprocessor instructions availability. Coprocessor instructions are
grouped as follows:
* ARM coprocessor instructions introduced in ARMv2
Includes: ldc, stc, mcr, mrc, cdp, ldcl, stcl
Guarded by: ARM_EXT_V2
Tests: copro-arm_v2plus-arm_v*.d
* ARM coprocessor instructions introduced in ARMv5
Includes: ldc2, ldc2l, stc2, stc2l, cdp2, mcr2, mrc2
Guarded by: ARM_EXT_V5
Tests: copro-arm_v5plus-arm_v*.d
* ARM coprocessor instructions introduced in ARMv5TE
Includes: mcrr, mrrc
Guarded by: ARM_EXT_V5E
Tests: copro-arm_v5teplus-arm_v*.d
* ARM coprocessor instructions introduced in ARMv6
Includes: mcrr2, mrrc2
Guarded by: ARM_EXT_V6
Tests: copro-arm_v6plus-arm_v*.d
* Thumb coprocessor instructions introduced in ARMv6T2
Includes: ldc, ldcl, stc, stcl, mcr, mrc, mcrr, mrrc, cdp, ldc2,
ldc2l, stc2, stc2l, cdp2, mcr2, mrc2, mcrr2, mrrc2
Guarded by: ARM_EXT_V6T2
Tests: copro-thumb_v6t2plus-thumb_v*.d
For each of these groups, at least 2 tests are performed:
* instructions are not available in earlier architecture
* instructions are available in architecture where they were introduced
More tests need to be performed when instructions in a group span
several assembly files.
Note that an instruction in the original coprocessor testcase is
changed to unified syntax to allow the testcase to be assembled for ARM
and Thumb state. Correct processing of legacy syntax is covered in other
testcases.
2017-11-01 Thomas Preud'homme <thomas.preudhomme@arm.com>
gas/
* config/tc-arm.c (arm_ext_v2): Define to ARM_EXT_V2 feature bit.
* testsuite/gas/arm/copro.s: Split into ...
* testsuite/gas/arm/copro-arm_v2plus-thumb_v6t2plus.s: This while
changing it to unified syntax and ...
* testsuite/gas/arm/copro-arm_v5plus-thumb_v6t2plus.s: this and ...
* testsuite/gas/arm/copro-arm_v5teplus-thumb_v6t2plus.s: This and ...
* testsuite/gas/arm/copro-arm_v6plus-thumb_v6t2plus.s: This.
* testsuite/gas/arm/copro.d: Split into ...
* testsuite/gas/arm/copro-arm_v2plus-arm_v2.d: This but target ARMv2
and ...
* testsuite/gas/arm/copro-arm_v5plus-arm_v5.d: this but target ARMv5
and ...
* testsuite/gas/arm/copro-arm_v5teplus-arm_v5te.d: This but target
ARMv5TE and ...
* testsuite/gas/arm/copro-arm_v6plus-arm_v6.d: This but target ARMv6.
* testsuite/gas/arm/copro-arm_v2plus-arm_v1.d: New testcase.
* testsuite/gas/arm/copro-thumb_v6t2plus-thumb_v4t-1.d: New testcase.
* testsuite/gas/arm/copro-arm_v2plus-thumb_v6t2plus-unavail.l: Expected
errors for the above two testcases.
* testsuite/gas/arm/copro-thumb_v6t2plus-thumb_v6t2-1.d: New testcase.
* testsuite/gas/arm/copro-arm_v5plus-arm_v4.d: New testcase.
* testsuite/gas/arm/copro-thumb_v6t2plus-thumb_v4t-2.d: New testcase.
* testsuite/gas/arm/copro-arm_v5plus-thumb_v6t2plus-unavail.l:
Expected errors for the above two testcases.
* testsuite/gas/arm/copro-thumb_v6t2plus-thumb_v6t2-2.d: New testcase.
* testsuite/gas/arm/copro-arm_v5teplus-arm_v5.d: New testcase.
* testsuite/gas/arm/copro-thumb_v6t2plus-thumb_v4t-3.d: New testcase.
* testsuite/gas/arm/copro-arm_v5teplus-thumb_v6t2plus-unavail.l:
Expected errors for the above two testcases.
* testsuite/gas/arm/copro-thumb_v6t2plus-thumb_v6t2-3.d: New testcase.
* testsuite/gas/arm/copro-arm_v6plus-arm_v5te.d: New testcase.
* testsuite/gas/arm/copro-thumb_v6t2plus-thumb_v4t-4.d: New testcase.
* testsuite/gas/arm/copro-arm_v6plus-thumb_v6t2plus-unavail.l:
Expected errors for the above two testcases.
* testsuite/gas/arm/copro-thumb_v6t2plus-thumb_v6t2-4.d: New testcase.
Without 64-bit bfd, we can't properly support .code64 directive in
32-bit mode.
* config/tc-i386.c (md_pseudo_table): Add .code64 directive
only if BFD64 is defined.
* testsuite/gas/i386/code64-inval.l: New file.
* gas/testsuite/gas/i386/code64-inval.s: Likewise.
* gas/testsuite/gas/i386/code64.d: Likewise.
* gas/testsuite/gas/i386/code64.s: Likewise.
* testsuite/gas/i386/i386.exp: Run mixed-mode-reloc32,
att-regs, intel-regs, intel-expr and string-ok tests only if
assembler supports x86-64. Run code64 and code64-inval.
Systems without the C extension mandate 4-byte alignment for
instructions, so there is no reason to allow for 2-byte alignment. This
change avoids emitting lots of unimplemented instructions into object
files on non-C targets, which users keep reporting as a bug. While this
isn't actually a bug (as none of the offsets in object files are
relevant until RISC-V), it is ugly.
gas/ChangeLog
2017-10-23 Palmer Dabbelt <palmer@dabbelt.com>
* config/tc-riscv.c (riscv_frag_align_code): Align code by 4
bytes on non-RVC systems.
Fix a bug in MIPS n32 ELF object file generation and make such objects
consistent with the n32 BFD requested, by presetting the EF_MIPS_ABI2
flag in the `e_flags' member of the newly created ELF file header, as it
is this flag that tells n32 objects apart from o32 objects.
This flag will then stay set through to output file generation for
writers such as GAS or GDB's `generate-core-file' command. Readers will
overwrite the whole of `e_flags' along with the rest of the ELF file
header in `elf_swap_ehdr_in' and then verify in `mips_elf_n32_object_p'
that the flag is still set before accepting an input file as an n32
object.
The issue was discovered with GDB's `generate-core-file' command making
o32 core files out of n32 debuggees.
bfd/
* elfn32-mips.c (mips_elf_n32_mkobject): New prototype and
function.
(bfd_elf32_mkobject): Use `mips_elf_n32_mkobject' rather than
`_bfd_mips_elf_mkobject'.
gas/
* config/tc-mips.c (mips_elf_final_processing): Don't set
EF_MIPS_ABI2 in `e_flags'.