Currently some of the instructions in bitmanip extensions can not be obtained
using DECLARE_INSN macros. I generated them using riscv-opcodes and added to
other opcodes.
Approved-By: Nelson Chu <nelson@rivosinc.com>
The Floating Point Mode Register is a new register which controls the
behaviour of FP8 instructions. This is handled by the Linux kernel
through a new NT_ARM_FPMR register set.
This patch adds required code to support core file dumps with
NT_ARM_FPMR in them.
Addressing (an old) review comment suggesting this housekeeping item.
Use consistent naming style in libsframe. sframe_decoder_ctx objects
are named 'dctx', so use 'ectx' for sframe_encoder_ctx objects.
Make necessary changes in all the applicable declarations and definitions.
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Update readelf to display the base symbol version as
Symbol table for image contains 5 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000003008 0 OBJECT GLOBAL DEFAULT 10 bar@@
2: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS VERS_1
3: 0000000000003008 0 OBJECT GLOBAL DEFAULT 10 bar@@VERS_1
4: 0000000000003000 0 OBJECT GLOBAL DEFAULT 10 foo@
instead of
Symbol table for image contains 5 entries:
Num: Value Size Type Bind Vis Ndx Name
0: 0000000000000000 0 NOTYPE LOCAL DEFAULT UND
1: 0000000000003008 0 OBJECT GLOBAL DEFAULT 10 bar
2: 0000000000000000 0 OBJECT GLOBAL DEFAULT ABS VERS_1
3: 0000000000003008 0 OBJECT GLOBAL DEFAULT 10 bar@@VERS_1
4: 0000000000003000 0 OBJECT GLOBAL DEFAULT 10 foo
That is bar@@ and foo@ vs bar and foo.
binutils/
PR binutils/33599
* readelf.c (process_version_sections): Replace 0x8001 with
(VERSYM_HIDDEN | VERSYM_BASE).
(get_symbol_version_string): Likewise. Return "" for the base
version.
include/
PR binutils/33599
* elf/common.h (VERSYM_BASE): New.
ld/
PR binutils/33599
* testsuite/ld-elf/pr33599.d: New file.
* testsuite/ld-elf/pr33599.map: Likewise.
* testsuite/ld-elf/pr33599.s: Likewise.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Change argument names (in declaration) to SF_BUF and SF_SIZE (instead of
the current CF_BUF and CF_SIZE respectively).
include/
* sframe-api.h (sframe_decode): Fix typos. Use same name as
used for the definition.
There's no need for a hook; what needs doing is uniform, the question is
only whether to perform any merging (i.e. whether other parts of a backend
are capable of dealing with the effects).
Where _bfd_nolink_bfd_merge_sections() was used, false is hardcoded. For
ELF no real target override is permitted; true is hardcoded except for the
cases where bfd_generic_merge_sections() was used as the hook function
before.
As SFrame format evolves, this will be useful to refer to v2 on-disk
layout directly as the format evolves.
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
include/
* sframe.h (struct sframe_func_desc_entry): Rename to tag v2.
In DWARF CFI an "undefined" register rule for the return address (RA)
register indicates that there is no return address and the stack trace
is complete.
Represent DW_CFA_undefined as SFrame FRE without any offsets, so that a
stack tracer implementation can use this as indication that an outermost
frame has been reached and the stack trace is complete.
This representation is backward compatible, as existing stack tracers
should already deal with the case, that an SFrame FRE a so far invalid
offset count of zero and stop the trace.
include/
* sframe.h (SFRAME_V2_FRE_RA_UNDEFINED_P): New macro to test
FRE info word for RA undefined (FRE without any offsets).
binutils/
* NEWS: Mention SFrame can represent an undefined RA as FRE
without any offsets.
gas/
* gen-sframe.h (struct sframe_row_entry): Add ra_undefined_p
flag.
* gen-sframe.c (sframe_row_entry_new): Initialize ra_undefined_p
flag to not set.
(sframe_row_entry_initialize): Treat ra_undefined_p flag as
sticky.
(sframe_fre_set_ra_track): Reset ra_undefined_p flag.
(sframe_xlate_do_restore): Reset ra_undefined_p flag to saved
state.
(sframe_xlate_do_same_value): Reset ra_undefined_p flag.
(sframe_xlate_do_cfi_undefined): For RA set ra_undefined_p flag.
(output_sframe_row_entry): Represent RA undefined as SFrame FRE
without any offsets and FRE info word fields zeroed.
* NEWS: Mention assembler represents .cfi_undefined RA in SFrame
as FRE without any offsets.
libsframe/
* doc/sframe-spec.texi (Changes from Version 1 to Version 2):
Mention that a SFrame FRE without any offsets flag indicates an
outermost frame with an undefined RA.
(fre_offset_count): Document that a FRE offset count of zero
indicates an outermost frame with an undefined RA.
* sframe.c (sframe_get_fre_ra_undefined_p): Use macro
SFRAME_V2_FRE_RA_UNDEFINED_P.
(sframe_fre_get_fp_offset, sframe_fre_get_ra_offset): Do not
return fixed FP/RA offset if RA undefined.
* sframe-dump.c (dump_sframe_func_with_fres): Show FRE without
any offsets as "RA undefined".
gas/testsuite/
* gas/cfi-sframe/cfi-sframe.exp: Run tests for .cfi_undefined RA
on AArch64, s390x, and x86-64.
* gas/cfi-sframe/cfi-sframe-aarch64-ra-undefined-1.d: Add test
for .cfi_undefined RA on AArch64.
* gas/cfi-sframe/cfi-sframe-aarch64-ra-undefined-1.s: Likewise.
* as/cfi-sframe/cfi-sframe-s390x-ra-undefined-1.d: Add test
for .cfi_undefined RA on s390x.
* gas/cfi-sframe/cfi-sframe-s390x-ra-undefined-1.s: Likewise.
* gas/cfi-sframe/cfi-sframe-x86_64-ra-undefined-1.d: Add test
for .cfi_undefined RA on x86-64.
* gas/cfi-sframe/cfi-sframe-x86_64-ra-undefined-1.s: Likewise.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
SFrame FREs without any offsets will later be used to represent an
undefined return address (RA) in SFrame. This API can then be used,
for instance by libsframe when dumping SFrame stack trace information
(e.g. in objdump and readelf), to test for RA undefined. Other users
of libsframe need the same capability.
include/
* sframe-api.h (sframe_fre_get_ra_undefined_p): New declaration.
libsframe/
* libsframe.ver (sframe_fre_get_ra_undefined_p): List new API.
* sframe.c (sframe_fre_get_ra_undefined_p): New definition.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
A check in print_insn_aarch64_word asserted that part of the encoding
space couldn't contain any valid encodings, and then returned ERR_NYI
("Not Yet Implemented", perhaps?) for these values. However, some of
the new FEAT_MOP4 instructions will trigger the assert. The check seems
to be outdated, and is clearly no longer valid, so it can just be
deleted.
Additionally, there are no other assignments of ERR_NYI, so delete all
remaining references to this error type.
Add new instructions from the Generic Interrupt Controller, GICv5,
extension. These instructions are aliases to system instructions and are
the following:
* gic <operation>, <reg>
* gicr <reg>, <operation>
* gsb <operation>
Generic Interrupt Controller v5, GICv5, adds new system registers
and system instructions. These are enabled with the +gcie flag, where
gcie stands for GICv5 (Generic Interrupt Controller) CPU Interrupt
Extension.
This is the binutils fix for PR 33384. Here we are assuming that no
const char* comma-separated option strings are passed in to
disassemble_info.disassembler_options. That is true for current usage
in gdb and binutils. In fact, there is only one place that passes a
string in read-only memory, gdb/tdep-i386.c:disassembly_flavor, and
that one is a single option.
include/
* dis-asm.h (struct disassemble_info): Comment.
(disassembler_options_cmp, next_disassembler_option),
(FOR_EACH_DISASSEMBLER_OPTION): Delete.
(for_each_disassembler_option): Declare.
opcodes/
* disassemble.c (disassembler_options_cmp): Delete.
(for_each_disassembler_option): New function.
* arc-dis.c (parse_option): Replace disassembler_options_cmp
with strcmp.
(parse_cpu_option): Likewise.
(parse_disassembler_options): Replace FOR_EACH_DISASSEMBLER_OPTION
with for_each_disassembler_option, and extract loop body to..
(arc_parse_option): ..this new function.
* arm-dis.c (parse_arm_disassembler_options): Delete, extracting
loop body to..
(arm_parse_option): ..this new function.
(print_insn): Use for_each_disassembler_option.
* csky-dis.c (parse_csky_dis_options): Delete, extracting loop
body to..
(parse_csky_option): ..this new function.
(print_insn_csky): Use for_each_disassembler_option.
* nfp-dis.c (parse_disassembler_options): Replace
FOR_EACH_DISASSEMBLER_OPTION with for_each_disassembler_option,
and extract loop body to..
(nfp_parse_option): ..this new function. Use opcodes_error_handler
here rather than info->fprintf_func to print error.
* ppc-dis.c (ppc_parse_cpu): Replace disassembler_options_cmp
with strcmp.
(struct ppc_parse_data): New.
(powerpc_init_dialect): Adjust to use new struct. Replace
FOR_EACH_DISASSEMBLER_OPTION with for_each_disassembler_option,
and extract loop body to..
(ppc_parse_option): ..this new function.
Silence -Wundef when ARCH_SIZE is not defined by checking that it is
defined before comparing its value.
Signed-off-by: Andrew Hanson <andrew@andrewhanson.dev>
include/
* binary-io.h: Fix -Wundef compiler warning when O_BINARY is not
defined. Wrap the check to ensure portability across platforms.
Signed-off-by: Andrew Hanson <andrew@andrewhanson.dev>
Before GCC PR114186, all looked good in the land of
multidimensional arrays: you wrote
int a[5][10];
and ctf_type_aname() et al would print it as
int [5][10]
Unfortunately this was two bugs in one. GCC was emitting the array as if
it were int a[10][5], i.e. as this:
a -> [10] -> [5] -> int
rather than
a -> [5] -> [10] -> int
as it should be. libctf was hiding this by printing them in the wrong
order, concealing the bug from anyone using objdump --ctf or anything
but actual type graph traversal. Once this was fixed for GCC, the bug
was visible in libctf: multidimensional arrays were printed backwards!
(But this is just a print-time bug: the underlying bug, that something
traversing the type graph would see the array in backwards order, was
fixed by the fix to GCC.)
Fix this libctf bug, printing the arrays the right way round. In a
possibly futile attempt to retain some vestige of backwards
compatibility, introduce a new bug-compat flag CTF_F_ARRNELEMS, which,
if on, indicates that PR114186 is fixed and GCC is emitting array
elements the right way round. (Unfortunately, the fix went in without
this flag, so some GCCs will still emit CTF that will cause libctf to
print them wrong, even with this fix -- but it's no wronger than it was
before, and new GCC and new binutils, as well as GCC older than any fix
for PR114186 and new binutils, will print things properly. Someone
traversing the type graph will see things right after the GCC fix, wrong
before it, and there isn't really any reliable way to tell which you
have, though if CTF_F_ARRNELEMS is set, you definitely have a fixed GCC.
The test checks for this, but it's not something we expect actual users
to ever do -- CTF dict flags are an internal implementation detail with
no user-visible API for a reason.)
[nca: log message, test compat with older compilers]
include/
* ctf.h (CTF_F_ARRNELEMS): New bug-compat flag.
(CTF_F_MAX): Adjust.
libctf/
PR libctf/32161
* ctf-decl.c (ctf_decl_push): Prepend if this is an array and
the bug-compat flag is set.
* ctf-dump.c (ctf_dump_header): Dump the new bug-compat flag.
* testsuite/libctf-lookup/multidim-array*: New test.
Many feature bits were unnecessarily added for features with no command
line flags, and effectively acted as aliases of the architecture version
bit they were linked to. The system register regating patch removed all
uses of these feature bits, so we can just remove them.
The flag is unnecessary, because we can just unconditionally check the
features field every time. Having the information duplicated in two
separate fields makes it harder to maintain, particularly in the context
of the upcoming regating patch.
The reg_flags parameter of aarch64_sys_ins_reg_supported_p is now
unused, so remove that as well.
This modifies some of the PR 21813 fixes, allowing for smaller EIHD.
Not knowing any better, I chose to use EIHD__C_LENGTH as the minimum
length.
include/
* vms/eihd.h (EIHD__C_LENGTH): Comment.
bfd/
* vms-alpha.c (_bfd_vms_slurp_eihd): Remove size check
duplicating that done by the caller of this function.
(alpha_vms_object_p): Allow smaller EIHD.
(evax_bfd_print_image): Likewise. Don't print fields past
the record size.
Commit 012d442686 effectively made peXXigen.c _bfd_XXi_swap_aux_out
always use the COFF E_FILNMLEN of 14. The problem was that the auxent
x_fname field was defined in include/coff/external.h using a length of
14. Later, E_FILNMLEN is redefined to 18 in coff/pe.h. This no doubt
falsely tripped memory checking tools. AUXESZ is 18, so no actual
buffer overrun.
This patch defines x_fname as an 18 char field, the full auxent, and
uses E_FILNMLEN when accessing.
PR 33302
include/
* coff/external.h (union external_auxent): Make x_fname
AUXESZ chars.
bfd/
* coffswap.h (coff_swap_aux_in): Correct #error message.
(coff_swap_aux_out): Likewise. Use E_FILNMLEN when copying
to ext field.
* peXXigen.c (_bfd_XXi_swap_aux_in): Add #error. Style fix.
(_bfd_XXi_swap_aux_out): Add #error. Don't use sizeof, use
E_FILNMLEN when copying to ext field.
gas
* testsuite/gas/pe/long_file_symbol.d,
* testsuite/gas/pe/long_file_symbol.s: New test.
* testsuite/gas/pe/pe.exp: Run it.
Reported-By: Frediano Ziglio <freddy77@gmail.com>
Mostly whitespace fixes and wrap of long comment lines, removal of block
comments and moving a few defines around. Nothing much to see here,
but AUXESZ before union external_auxent is needed by the next patch.
* coff/external.h: Whitespace fixes, wrap long comment lines,
remove header style comments. Move some defines.
(E_FILNMLEN): Remove #ifndef.
(_ETEXT): Don't define.
(SYMENT, AUXENT): Don't define, make them typedefs.
* coff/internal.h: Whitespace fixes, wrap long comment lines,
remove header style comments. Move some defines.
(signed): Don't define.
Use stat, instead of strcmp, to check if the same linker script file
appears multiple times for
$ ld -L... -T ././/script.t -T script.t ...
Although ././/script.t and script.t access the same file, but their
filenames are different. strcmp won't work here.
Copy gnulib/import/same-inode.h to include since the gnulib directory
isn't included in the binutils tarball.
include/
PR ld/24576
* same-inode.h: New file. Copied from gnulib/import/same-inode.h.
ld/
PR ld/24576
* ldfile.c: Include "same-inode.h".
(ldfile_find_command_file): Change the second argument from bool
to enum script_open_style. Check if the same linker script file
appears multiple times by using stat, instead using strcmp.
(ldfile_open_command_file_1): Don't check if the same linker
script file appears multiple times here.
* testsuite/ld-scripts/pr24576-1.d: Adjusted.
* testsuite/ld-scripts/pr24576-2.d: New.
* testsuite/ld-scripts/script.exp: Run pr24576-2.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Add new command line option -z memtag-stack for aarch64 elf. This
option instructs the linker to generate the necessary dynamic tag
DT_AARCH64_MEMTAG_STACK, which the dynamic loader can then use to
protect the stack memory with PROT_MTE. Linker issues an
'unrecognized option' error when -z memtag-stack is specified for
non-aarch64 based emulations.
readelf displays the dynamic tag when present:
$ readelf -d <exectutable>
Dynamic section at offset 0xfdd8 contains XX entries:
Tag Type Name/Value
0x0000000000000001 (NEEDED) Shared library: [libc.so.6]
0x000000000000000c (INIT) 0x400520
0x000000000000000d (FINI) 0x400b64
0x0000000000000019 (INIT_ARRAY) 0x41fdc8
... ... ...
0x000000007000000c (AARCH64_MEMTAG_STACK) 0x1
... ... ...
ChangeLog:
* bfd/elfnn-aarch64.c (elfNN_aarch64_late_size_sections): Emit
DT_AARCH64_MEMTAG_STACK dynamic tag.
* bfd/elfxx-aarch64.h (struct aarch64_memtag_opts): Add new
member for tracking whether stack access uses MTE insns.
* binutils/readelf.c (get_aarch64_dynamic_type): Handle
DT_AARCH64_MEMTAG_STACK.
* ld/emultempl/aarch64elf.em: Add new command line option.
* ld/ld.texi: Add documentation for -z memtag-stack.
* ld/testsuite/ld-aarch64/aarch64-elf.exp: Add new test.
* ld/testsuite/ld-aarch64/dt-memtag-stack.d: New test.
include/ChangeLog:
* elf/aarch64.h (DT_AARCH64_MEMTAG_STACK): New definition.
Add new command line option -z memtag-mode=<mode> to aarch64 elf,
where <mode> can be one of none, sync, or async. For mode of sync or
async, a DT_AARCH64_MEMTAG_MODE dynamic tag with a value of 0 or 1
respectively is emitted.
readelf displays the dynamic tag when present:
$ readelf -d <exectutable>
Dynamic section at offset 0xfdd8 contains XX entries:
Tag Type Name/Value
0x0000000000000001 (NEEDED) Shared library: [libc.so.6]
0x000000000000000c (INIT) 0x400520
0x000000000000000d (FINI) 0x400b64
0x0000000000000019 (INIT_ARRAY) 0x41fdc8
... ... ...
0x0000000070000009 (AARCH64_MEMTAG_MODE) 0x1
... ... ...
Note that this patch doesn't add support for the "asymm" MTE mode,
which is an Armv8.7 extension.
ChangeLog:
* bfd/elfnn-aarch64.c (struct elf_aarch64_link_hash_table): Add
new member for memtag properties.
(bfd_elfNN_aarch64_set_options): New argument to pass memtag
properties.
(elfNN_aarch64_late_size_sections): Emit DT_AARCH64_MEMTAG_MODE
dynamic tag.
* bfd/elfxx-aarch64.h: New definition for the various memtag
properties.
* binutils/readelf.c (get_aarch64_dynamic_type): Handle
DT_AARCH64_MEMTAG_MODE.
* ld/emultempl/aarch64elf.em: Likewise.
* ld/ld.texi: Add documentation for the new option
-z memtag-mode.
* ld/testsuite/ld-aarch64/aarch64-elf.exp: New test.
* ld/testsuite/ld-aarch64/dt-memtag.d: New test.
* ld/testsuite/ld-aarch64/dt-memtag-mode.s: New test.
include/ChangeLog:
* elf/aarch64.h (DT_AARCH64_MEMTAG_MODE): New definition.
When parsing immediate values, register names should not be
misinterpreted as symbols. However, for backwards compatibility we need
to permit some newer register names within older instructions. The
current mechanism for doing so depends on the list of explicit
architecture requirements for the instructions, which is fragile and
easy to forget, and grows increasingly messy as more architecture
features are added.
This patch add explicit flags to each opcode to indicate which set of
register names is disallowed in each instance. These flags are
mandatory for all opcodes with immediate operands, which ensures that
the choice of disallowed names will always be deliberate and explicit.
This patch should have no functional change.
Remove LIBSFRAME_1.1, LIBSFRAME_1.0 nodes and add a new LIBSFRAME_2.0
node (non-inheritance version) to create new global versioned symbols.
Also announce libsframe.so.2 in NEWS.
New APIs:
sframe_decoder_get_flags;
sframe_decoder_get_offsetof_fde_start_addr;
sframe_encoder_get_flags;
sframe_encoder_get_offsetof_fde_start_addr;
Removed APIs: (already deprecated since X-2 release)
sframe_get_funcdesc_with_addr;
APIs with changed semantics:
sframe_decoder_get_funcdesc_v2;
sframe_encoder_add_funcdesc_v2;
sframe_encoder_write;
lisbframe/
* libsframe.ver: Define new LIBSFRAME_2.0.
* libtool-version: Bump the 'current' numeral to indicate a binary
incompatible release.
include/
* sframe-api.h (sframe_get_funcdesc_with_addr): Remove
deprecated interface.
libsframe/
* sframe.c (sframe_get_funcdesc_with_addr): Likewise.
binutils/
* NEWS: Announce new versioned release of libsframe.
So far, SFrame sections were of type SHT_PROGBITS.
As per ELF specification, SHT_PROGBITS indicates that the section holds
information defined by the program, whose format and meaning are
determined solely by the program.
On the linker side, SHT_PROGBITS should be reserved for the simple "cat
contents after applying relocs" semantics.
Currently, the only way to know that a section contains SFrame stack
trace data is if consumer checks for section name. Such a check for
section name is not quite conformant to ELF principles.
Some of this was discussed here
https://sourceware.org/pipermail/binutils/2025-March/140181.html
With this change, the SFrame sections generated by gas, ld will have
section type set to SHT_GNU_SFRAME. The new section type is defined in
the SHT_LOOS/SHT_HIOS space. The SFrame parsing routine
_bfd_elf_parse_sframe () now admits sections only when the the section
type is SHT_GNU_SFRAME.
No special handling / validation is done at the moment for the case of
manual creation of SFrame sections via obj_elf_section (). Add function
level comments for now to add a note about this.
Although the default handling for (sh_type >= SHT_LOOS && sh_type <=
SHT_HIOS) is sufficient when SHT_GNU_SFRAME is in that range, it makes
sense to add it as a case of its own.
bfd/
* elf-sframe.c (_bfd_elf_parse_sframe): Check if section type is
SHT_GNU_SFRAME.
(_bfd_elf_set_section_sframe): Set SHT_GNU_SFRAME for output
SFrame section.
* elflink.c (obj_elf_section): Use section type for check
instead of section name.
* elfxx-x86.c: Set SHT_GNU_SFRAME for SFrame sections for
.plt* sections.
* elf.c (bfd_section_from_shdr): Add case for SHT_GNU_SFRAME.
binutils/
* readelf.c (get_os_specific_section_type_name): Add
SHT_GNU_SFRAME.
gas/
* NEWS: Announce emitted SFrame sections have SHT_GNU_SFRAME
set.
* config/obj-elf.c (obj_elf_attach_to_group): Add comments to
indicate no special handling for SFrame yet.
* dw2gencfi.c (cfi_finish): Set SHT_GNU_SFRAME for emitted
SFrame section.
ld/
* NEWS: Announce emitted SFrame sections have SHT_GNU_SFRAME
set.
gas/testsuite/
* gas/cfi-sframe/cfi-sframe.exp: Add new test.
* gas/cfi-sframe/cfi-sframe-common-1b.d: New test.
* gas/cfi-sframe/cfi-sframe-common-1b.s: New test.
include/
* elf/common.h (SHT_GNU_SFRAME): Add new section type for SFrame
stack trace information.
libsframe/doc/
* sframe-spec.texi: Add expected ELF section type.
FEAT_SVE_AES2 implements the SVE multi-vector Advanced Encryption
Standard and 128-bit destination element polynomial multiply long
instructions, when the PE is not in Streaming SVE mode.
FEAT_PCDPHINT - Producer-consumer data placement hints - is an optional
ISA extension that provides hint instructions to indicate:
- a store in the current execution thread is generating data at a specific
location, which a thread of execution on one or more other observers is
waiting on.
- the thread of execution on the current PE will read a location that may not
yet have been written with the value to be consumed.
This extension introduces:
- STSHH, a hint instruction, with operands (policies) keep and strm
- PRFM *IR*, a new prefetch memory operand.
In SFrame V2 the size of the offsets following an SFrame FRE can be
either signed 8-bit, 16-bit, or 32-bit integer, with the largest offset
determining their size:
1. CFA offset from CFA base register
2. RA (stack save slot) offset from CFA, usually -48 on s390x if saved
3. FP (stack save slot) offset from CFA, usually -72 on s390x if saved
The FP and RA offsets from CFA, when FP/RA saved on the stack, usually
have fixed values that fit into signed 8-bit SFrame offsets. Likewise
the DWARF register numbers on s390x of general registers (GR; 0-15) and
floating-point registers (FPR; 16-31), when FP/RA saved in registers.
With that the CFA offset from CFA base register has the greatest impact
on the signed SFrame offset size.
The s390x ELF ABI defines the stack pointer (SP) to be 8-byte aligned
[1] and the CFA as SP at call site + 160 [2]. The CFA offset from CFA
base register is therefore always a multiple of 8.
On s390x store the SFrame CFA offset from CFA base register scaled down
by the s390x-specific CFA alignment factor of 8, in addition to the
adjustment by the s390x-specific CFA adjustment of -160, to further
improve the use of signed 8-bit SFrame offsets. This is similar to the
DWARF data alignment factor getting factored out from certain offsets
stored in DWARF CFI.
[1]: s390x ELF ABI, sections "Register Roles" and "Stack Frame
Allocation", https://github.com/IBM/s390x-abi/releases
[2]: s390x ELF ABI, commit 4e38ad9c8a88 ("Document the CFA"),
https://github.com/IBM/s390x-abi/commit/4e38ad9c8a88
include/
* sframe.h (SFRAME_S390X_CFA_OFFSET_ALIGNMENT_FACTOR): Define
s390x-specific CFA offset alignment factor.
(SFRAME_V2_S390X_CFA_OFFSET_ENCODE,
SFRAME_V2_S390X_CFA_OFFSET_DECODE): Scale down/up by
SFRAME_S390X_CFA_OFFSET_ALIGNMENT_FACTOR.
libsframe/
* doc/sframe-spec.texi (s390x,
SFRAME_S390X_CFA_OFFSET_ALIGNMENT_FACTOR): Document s390x-
specific CFA offset alignment factor.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
In SFrame V2 the size of the offsets following an SFrame FRE can be
either signed 8-bit, 16-bit, or 32-bit integer, with the largest offset
determining their size:
1. CFA offset from CFA base register
2. RA (stack save slot) offset from CFA, usually -48 on s390x if saved
3. FP (stack save slot) offset from CFA, usually -72 on s390x if saved
The FP and RA offsets from CFA, when FP/RA saved on the stack, usually
have fixed values that fit into signed 8-bit SFrame offsets. Likewise
the DWARF register numbers on s390x of general registers (GR; 0-15) and
floating-point registers (FPR; 16-31), when FP/RA saved in registers.
With that the CFA offset from CFA base register has the greatest impact
on the signed SFrame offset size.
The s390x ELF ABI [1] defines the CFA as stack pointer (SP) at call
site +160. [2] Therefore the minimum CFA offset from CFA base register
on s390x is 160. This does not fit into a signed 8-bit integer and
therefore effectively prevents any use of signed 8-bit SFrame offsets
on s390x.
For s390x store the CFA offset from CFA base register adjusted by -160
to enable the use of signed 8-bit SFrame offsets.
[1]: s390x ELF ABI, https://github.com/IBM/s390x-abi/releases
[2]: s390x ELF ABI, commit 4e38ad9c8a88 ("Document the CFA"),
https://github.com/IBM/s390x-abi/commit/4e38ad9c8a88
include/
* sframe.h (SFRAME_S390X_CFA_OFFSET_ADJUSTMENT): Define
s390x-specific CFA offset adjustment.
(SFRAME_V2_S390X_CFA_OFFSET_ENCODE,
SFRAME_V2_S390X_CFA_OFFSET_DECODE): New s390x-specific
macros. Use SFRAME_S390X_CFA_OFFSET_ADJUSTMENT to en-/decode
CFA offset.
bfd/
* elf64-s390.c (elf_s390x_sframe_plt_fre): Use
SFRAME_V2_S390X_CFA_OFFSET_ENCODE on CFA offset to store it
adjusted and switch to 8-bit offsets.
gas/
* gen-sframe.c (sframe_fre_set_cfa_offset): For s390x use
SFRAME_V2_S390X_CFA_OFFSET_ENCODE on CFA offset to store it
adjusted.
(sframe_fre_get_cfa_offset): New helper. For s390x use
SFRAME_V2_S390X_CFA_OFFSET_DECODE on CFA offset to undo its
adjustment.
(sframe_xlate_do_def_cfa_register): Use new helper
sframe_fre_get_cfa_offset.
libsframe/
* sframe.c (sframe_fre_get_cfa_offset): For s390x use
SFRAME_V2_S390X_CFA_OFFSET_DECODE on CFA offset to undo its
adjustment.
* doc/sframe-spec.texi (s390x,
SFRAME_S390X_CFA_OFFSET_ADJUSTMENT,
SFRAME_V2_S390X_CFA_OFFSET_ENCODE,
SFRAME_V2_S390X_CFA_OFFSET_DECODE): Document s390x-specific
adjustment of CFA offset.
libsframe/testsuite/
* libsframe.find/plt-findfre-2.c (add_plt0_fde, add_pltn_fde):
Use SFRAME_V2_S390X_CFA_OFFSET_ENCODE to enable use of 1-byte
SFrame offsets.
Suggested-by: Indu Bhagat <indu.bhagat@oracle.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
If an architecture uses both SFrame RA and FP tracking SFrame assumes
that the RA offset is the 2nd offset and the FP offset is the 3rd offset
following a SFrame FRE. An architecture does not necessarily need to
save both on the stack (or in register) at the same time or even at all.
SFrame cannot represent FP without RA saved on stack (or in a register),
since it cannot distinguish whether the 2nd offset is the RA or FP
offset.
For s390x use an invalid SFrame RA offset from CFA value of zero as
padding to represent the FP being saved when the RA is not saved. This
aligns with the existing invalid SFrame fixed RA offset from CFA value
of zero. In a stack tracer this then also naturally falls into place,
as it can skip restoring the RA in the topmost frame, if both the fixed
RA offset (from SFrame header) and the RA offset (from FDE) are zero,
without any need to test architecture-specific flags.
include/
* sframe.h (SFRAME_FRE_RA_OFFSET_INVALID): New define. Used as
padding offset.
* sframe-api.h (sframe_fre_get_ra_offset): Add comment that for
s390x an offset value of SFRAME_FRE_RA_OFFSET_INVALID indicates
that the RA is not saved.
gas/
* gen-sframe.c (get_fre_num_offsets): For s390x account padding
RA offset, if FP without RA saved.
(sframe_get_fre_offset_size): Likewise.
(output_sframe_row_entry): For s390x write a padding RA offset,
if FP without RA needs to be represented.
(sframe_do_fde): Enable FP without RA saved to be represented
on s390x.
libsframe/
* sframe.c (sframe_fre_get_ra_offset): Add comment that for
s390x an offset value of SFRAME_FRE_RA_OFFSET_INVALID indicates
that the RA is not saved.
* sframe-dump.c (dump_sframe_func_with_fres): Treat invalid
RA offsets as if they were undefined. Display them as "U"
to distinguish them.
* doc/sframe-spec.texi (s390x): Document s390x-specific use of
SFRAME_FRE_RA_OFFSET_INVALID to represent FP without RA saved.
gas/testsuite/
* gas/cfi-sframe/cfi-sframe.exp: Rename s390x-specific tests.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-offset-err-1.s: Rename
to ...
* cfi-sframe/cfi-sframe-s390x-fpra-offset-err-1.d: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-offset-2.s: This.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-offset-2.d: Likewise.
Update test verification pattern accordingly.
* cfi-sframe/cfi-sframe-s390x-fpra-register-err-1.s: Rename
to ...
* cfi-sframe/cfi-sframe-s390x-fpra-register-err-1.d: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-2.s: This.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-2.d: Likewise.
Update test verification pattern accordingly.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
GCC on s390x, when in a leaf function, can be observed to save the
frame pointer (FP) and/or return address (RA) register in a floating-
point registers (FPR) instead of on the stack. This is declared using
the following CFI directive:
.cfi_register <fp/ra-regnum>, <fpr-regnum>
SFrame cannot represent the FP and/or RA being saved in another
register. It does only track the CFA base register (SP/FP), CFA offset
from CFA base register, and FP and RA save area offsets from CFA.
On s390x the FP and/or RA are only saved in another FPR when in a leaf
function. That is a function that does not call any other function.
Therefore it can ever only be the topmost function in a call chain.
An unwinder by default has access to all registers of the function that
is the topmost on the call stack. Therefore no further information
is required to restore FP/RA from the FPR.
Represent FP/RA saved in another register on s390x, by encoding the
DWARF register number shifted by one to the left with the least-
significant bit set in the offset as follows:
offset = (regnum << 1) | 1
The use of the least-significant bit of the offset as indication is
possible, as the stack pointer (SP), the CFA, and any register save
area slots are 8-byte aligned according to the s390x ELF ABI:
- The stack pointer (SP) "shall maintain an 8-byte alignment". [1]
- The CFA is defined as SP at call site +160. [2]
- Pointers and 8-byte integers, such as general register values, must
be 8-byte aligned. [3]
SFrame FP and RA stack offsets must therefore always be a multiple of
8 on s390x. Note that for the same reason the DWARF data alignment
factor is -8 on s390x (see DWARF2_CIE_DATA_ALIGNMENT).
Add s390x-specific SFrame (error) tests for FP/RA saved in FPRs in leaf
function.
[1]: s390x ELF ABI, sections "Register Roles" and "Stack Frame
Allocation", https://github.com/IBM/s390x-abi/releases
[2]: s390x ELF ABI, commit 4e38ad9c8a88 ("Document the CFA"),
https://github.com/IBM/s390x-abi/commit/4e38ad9c8a88
[3]: s390x ELF ABI, section "Fundamental Types", table "Scalar types",
https://github.com/IBM/s390x-abi/releases
include/
* sframe.h (SFRAME_V2_S390X_OFFSET_IS_REGNUM): New s390x-
specific macro to test whether an SFrame FP/RA offset is a DWARF
register number.
(SFRAME_V2_S390X_OFFSET_ENCODE_REGNUM): New s390x-specific macro
to encode a DWARF register number into an SFrame FP/RA offset.
(SFRAME_V2_S390X_OFFSET_DECODE_REGNUM): New s390x-specific macro
to decode an SFrame FP/RA offset into a DWARF register number.
* sframe-api.h (sframe_fre_get_fp_offset,
sframe_fre_get_fp_offset): Add comment that for s390x the offset
may be an encoded register number.
gas/
* gen-sframe.c (s390_sframe_xlate_do_register): New S390-
specific function. Uses SFRAME_V2_S390X_OFFSET_ENCODE_REGNUM to
represent FP/RA saved in another register on s390x.
(sframe_xlate_do_register): Invoke s390_sframe_xlate_do_register
on s390x.
libsframe/
* sframe.c (sframe_fre_get_fp_offset, sframe_fre_get_fp_offset):
Add comment that for s390x the offset may be an encoded register
number.
* sframe-dump.c (is_sframe_abi_arch_s390x): New helper to test
whether ABI/arch is s390x.
(dump_sframe_func_with_fres): Use
SFRAME_V2_S390X_OFFSET_IS_REGNUM and
SFRAME_V2_S390X_OFFSET_DECODE_REGNUM to dump FP/RA saved in
another register on s390x.
* doc/sframe-spec.texi (s390x): Document s390x-specific
representation of FP/RA saved in another register.
gas/testsuite/
* gas/cfi-sframe/cfi-sframe.exp: Update s390x-specific SFrame
(error) tests.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-err-2.s: Rename
to ...
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-err-2.d:
Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-1.s: This. Test
no longer triggers a warning, as SFrame can represent FP and RA
saved in registers.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-1.d: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-err-1.d: Test
now triggers a different warning, as SFrame can represent FP and
RA saved in registers, but not FP without RA saved in register.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
This introduces initial support to generate .sframe from CFI directives
in assembler on s390 64-bit (s390x). Due to SFrame V2 format
limitations it has the following limitations, some of them getting
addressed by subsequent patches, which cause generation of SFrame FDE
to be skipped:
- SFrame FP/RA tracking only supports register contents being saved on
the stack (i.e. .cfi_offset). It does not support FP/RA register
contents being saved in other registers (i.e. .cfi_register). GCC on
s390x can be observed to save the FP/RA register contents in floating-
point registers, but only in leaf functions.
This issue is detailed further and resolved in the subsequent commit
"s390: Represent FP/RA saved in register in SFrame".
- SFrame FP/RA tracking cannot represent FP without RA saved. This is
because the format assumes SFrame FDE offset2 to be the RA offset, if
there are two offsets, and offset3 to be the FP offset, if there are
three offsets. There is no mean to distinguish whether offset2 is the
RA or FP offset, if there are only two offsets.
This issue is detailed further and resolved in the subsequent commit
"s390: Represent FP without RA saved in SFrame".
- SFrame assumes a dedicated FP register number. The s390x ELF ABI [1]
does only designate register 11 as preferred FP register number. In
general GCC and Clang on s390x use register 11 as frame pointer.
GCC on s390x can be observed to use register 14 as frame pointer in
the stack clash protector in the function prologue.
glibc on s390x contains hand-written assembler code that uses
register 12 as frame pointer.
This s390x support is largely based on the AArch64 support from commit
b52c4ee466 ("gas: generate .sframe from CFI directives").
The SFrame ABI/arch identifier SFRAME_ABI_S390X_ENDIAN_BIG is introduced
for s390x and added to the SFrame format specification.
The s390x ELF ABI [1] specifies the following C calling conventions for
s390x architecture:
- Register 15 is the stack pointer (SP).
- Register 14 contains the return address (RA) at function entry.
- There is no dedicated frame pointer register. Register 11 is the
preferred frame pointer (FP). [2] GCC and Clang in general use
register 11 as frame pointer.
- The CFA is defined as SP at call site +160. [3] The SP at call site
can therefore be derived from the CFA using a SP value offset from CFA
of -160.
The s390x ELF ABI [1] does not assign any standard save slot to each
register in the register save area of a stack frame. Neither the
return address (RA, r14) nor preferred frame pointer (FP, r11)
necessarily need to be saved. Therefore SFrame RA and FP tracking is
used.
Support for SFrame on s390 is only enabled for the 64-bit s390x ELF ABI
(z/Architecture with 64-bit addressing mode). It is disabled for the
32-bit s390 ELF ABI (ESA/390 or z/Architecture with 32-bit addressing
mode).
s390x-specific SFrame assembler and linker tests are added, including
error tests for use of a non-preferred frame pointer (FP) register and
specification of a non-default return address (RA) register.
[1]: s390x ELF ABI, https://github.com/IBM/s390x-abi/releases
[2]: s390x ELF ABI, commit f00421825979 ("Add information about the frame
pointer register"),
https://github.com/IBM/s390x-abi/commit/f00421825979
[3]: s390x ELF ABI, commit 4e38ad9c8a88 ("Document the CFA"),
https://github.com/IBM/s390x-abi/commit/4e38ad9c8a88
include/
* sframe.h: Add reference to s390x architecture in comments.
(SFRAME_ABI_S390X_ENDIAN_BIG): Define SFrame ABI/arch identifier
for s390x.
(SFRAME_S390X_SP_VAL_OFFSET): Define s390x-specific SP value
offset from CFA.
libsframe/
* sframe.c (need_swapping): Add SFRAME_ABI_S390X_ENDIAN_BIG.
* doc/sframe-spec.texi (SFRAME_ABI_S390X_ENDIAN_BIG, s390x,
SFRAME_S390X_SP_VAL_OFFSET): Document SFrame ABI/arch identifier
for s390x, add references to s390x architecture, and document
s390x-specifics, such as the SP value offset from CFA of -160.
gas/
* config/tc-s390.h: s390x support to generate .sframe from CFI
directives in assembler.
(support_sframe_p): Define.
(SFRAME_CFA_SP_REG, SFRAME_CFA_FP_REG, SFRAME_CFA_RA_REG):
Define.
(sframe_ra_tracking_p): Define.
(sframe_cfa_ra_offset): Define.
(sframe_get_abi_arch): Define.
* config/tc-s390.c: s390x support to generate .sframe from CFI
directives in assembler.
(s390_sframe_cfa_sp_reg, s390_sframe_cfa_fp_reg,
s390_sframe_cfa_ra_reg): New. Initialize to DWARF register
numbers of stack pointer (SP, r15), preferred frame pointer
(FP, r11), and return address (RA, r14) registers.
(s390_support_sframe_p): New function. Return true if s390x.
(s390_sframe_ra_tracking_p): New function. Return true.
(s390_sframe_cfa_ra_offset): New function. Return
SFRAME_CFA_FIXED_RA_INVALID.
(s390_sframe_get_abi_arch): New function. Return
SFRAME_ABI_S390X_ENDIAN_BIG if s390x, otherwise zero.
* gen-sframe.c: Add reference to s390x architecture in comments.
(sframe_xlate_do_val_offset): Add support for s390x-specific
SFRAME_S390X_SP_VAL_OFFSET.
* NEWS: Add news entry.
gas/testsuite/
* gas/cfi-sframe/cfi-sframe.exp: Enable common SFrame tests for
s390x. Add s390x-specific SFrame (error) tests.
* gas/cfi-sframe/cfi-sframe-s390x-1.d: New s390x-specific SFrame
test.
* gas/cfi-sframe/cfi-sframe-s390x-1.s: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-2.d: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-2.s: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-err-1.d: New s390x-specific
SFrame error test that uses a non-default frame-pointer register
as CFA base register.
* gas/cfi-sframe/cfi-sframe-s390x-err-1.s: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-err-2.d: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-err-2.s: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-err-3.d: New s390x-specific
SFrame error test that uses a non-default return address
register.
* gas/cfi-sframe/cfi-sframe-s390x-err-3.s: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-offset-1.d: New s390x-
specific SFrame test that saves RA and FP individually on the
stack.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-offset-1.s: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-offset-err-1.d: New
s390x-specific SFrame error test that saves FP and RA
individually, to trigger FP without RA saved.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-offset-err-1.s: Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-err-1.d: New
s390x-specific SFrame error test that saves FP and RA
individually in registers.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-err-1.s:
Likewise.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-err-2.d: New
s390x-specific SFrame error test that saves RA and FP
individually in registers.
* gas/cfi-sframe/cfi-sframe-s390x-fpra-register-err-2.s:
Likewise.
ld/testsuite/
* ld-s390/s390.exp: Add simple SFrame test.
* ld-s390/sframe-simple-1.d: New simple SFrame test.
* ld-s390/sframe-bar.s: Likewise.
* ld-s390/sframe-foo.s: Likewise.
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
This also fix the imply result for .option rvc.
Imply zcf when c and f and rv32
Imply zcd when c and d
Imply zca when c
Changed INSN_CLASS_C to INSN_CLASS_ZCA
Changed INSN_CLASS_F_AND_C to INSN_CLASS_ZCF
Changed INSN_CLASS_D_AND_C to INSN_CLASS_ZCD
Changed INSN_CLASS_ZIHINTNTL_AND_C to INSN_CLASS_ZIHINTNTL_AND_ZCA
for SFRAME_V2_GNU_AS_LD_ENCODING_FLAGS.
The intention of creating an abstraction like
SFRAME_V2_GNU_AS_LD_ENCODING_FLAGS is to address the concern that there
should be a central place to enforce harmonious flags between GNU as and
ld. At the moment, the only flag that needs to be enforced is
SFRAME_F_FDE_FUNC_START_PCREL.
sframe.h and sframe-api.h are installed headers by libsframe for the
specification and implementation respectively. Adding a definition like
SFRAME_V2_GNU_AS_LD_ENCODING_FLAGS does not fit in either. Create a
new internal header instead to keep the definition uncoupled from
sframe.h and sframe-api.h. Rename the previously added
SFRAME_F_LD_MUSTHAVE_FLAGS to define the new
SFRAME_V2_GNU_AS_LD_ENCODING_FLAGS.
bfd/
* elf-sframe.c (_bfd_elf_merge_section_sframe): Use the new
internal header and SFRAME_V2_GNU_AS_LD_ENCODING_FLAGS.
gas/
* gen-sframe.c (output_sframe_internal): Likewise.
include/
* sframe-api.h (SFRAME_F_LD_MUSTHAVE_FLAGS): Move from..
* sframe-internal.h: ..to here. New file.
