There are no legacy ldind nor ldabs BPF instructions with BPF_SIZE_DW.
For some reason we were (incorrectly) supporting these. This patch
updates the opcodes so the instructions get removed and modifies the
GAS manual and testsuite accordingly.
See discussion at
https://lore.kernel.org/bpf/110aad7a-f8a3-46ed-9fda-2f8ee54dcb89@linux.dev
Tested in bpf-uknonwn-none target, x86-64-linux-gnu host.
include/ChangeLog:
2024-01-29 Jose E. Marchesi <jose.marchesi@oracle.com>
* opcode/bpf.h (enum bpf_insn_id): Remove BPF_INSN_LDINDDW and
BPF_INSN_LDABSDW instructions.
opcodes/ChangeLog:
2024-01-29 Jose E. Marchesi <jose.marchesi@oracle.com>
* bpf-opc.c (bpf_opcodes): Remove BPF_INSN_LDINDDW and
BPF_INSN_LDABSDW instructions.
gas/ChangeLog:
2024-01-29 Jose E. Marchesi <jose.marchesi@oracle.com>
* doc/c-bpf.texi (BPF Instructions): There is no indirect 64-bit
load instruction.
(BPF Instructions): There is no absolute 64-bit load instruction.
* testsuite/gas/bpf/mem.s: Update test accordingly.
* testsuite/gas/bpf/mem-be-pseudoc.d: Likewise.
* testsuite/gas/bpf/mem-be.d: Likewise.
* testsuite/gas/bpf/mem-pseudoc.d: Likewise.
* testsuite/gas/bpf/mem-pseudoc.s: Likewise.
* testsuite/gas/bpf/mem.d: Likewise.
* testsuite/gas/bpf/mem.s: Likewise.
Adds two new external authors to etc/update-copyright.py to cover
bfd/ax_tls.m4, and adds gprofng to dirs handled automatically, then
updates copyright messages as follows:
1) Update cgen/utils.scm emitted copyrights.
2) Run "etc/update-copyright.py --this-year" with an extra external
author I haven't committed, 'Kalray SA.', to cover gas testsuite
files (which should have their copyright message removed).
3) Build with --enable-maintainer-mode --enable-cgen-maint=yes.
4) Check out */po/*.pot which we don't update frequently.
The neg/neg32 BPF instructions always use BPF_SRC_K (=0) in their header
source bit, despite operating on registers. If BPF_SRC_X (=1) is set,
the instructions are rejected by the kernel.
Because of this there are also no neg/neg32 instructions which operate
on immediates, so remove them.
bd434cc4d9 was a similar fix in the old
CGEN-based port, but was not carried forward in the new port.
include/
* opcode/bpf.h (enum bpf_insn_id): Remove spurious entries
BPF_INSN_NEGI and BPF_INSN_NEG32I.
opcodes/
* bpf-opc.c (bpf_opcodes): Remove erroneous NEGI and NEG32I
instructions.
gas/
* doc/c-bpf.texi (BPF Instructions): Remove erroneous neg and
neg32 instructions operating on immediates.
* testsuite/gas/bpf/alu.s: Adapt accordingly.
* testsuite/gas/bpf/alu.d: Likewise.
* testsuite/gas/bpf/alu-be.d: Likewise
* testsuite/gas/bpf/alu32.s: Likewise.
* testsuite/gas/bpf/alu32.d: Likewise.
* testsuite/gas/bpf/alu32-be.d: Likewise.
* testsuite/gas/bpf/alu-pseudoc.s: Likewise.
* testsuite/gas/bpf/alu-pseudoc.d: Likewise.
* testsuite/gas/bpf/alu-be-pseudoc.d: Likewise.
* testsuite/gas/bpf/alu32-pseudoc.s: Likewise.
* testsuite/gas/bpf/alu32-pseudoc.d: Likewise.
* testsuite/gas/bpf/alu32-be-pseudoc.d: Likewise.
This patch adds support for EF_BPF_CPUVER bits in the ELF
machine-dependent header flags. These bits encode the BPF CPU
version for which the object file has been compiled for.
The BPF assembler is updated so it annotates the object files it
generates with these bits.
The BPF disassembler is updated so it honors EF_BPF_CPUVER to use the
appropriate ISA version if the user didn't specify an explicit ISA
version in the command line. Note that a value of zero in
EF_BPF_CPUVER is interpreted by the disassembler as "use the later
supported version" (the BPF CPU versions start with v1.)
The readelf utility is updated to pretty print EF_BPF_CPUVER when it
prints out the ELF header:
$ readelf -h a.out
ELF Header:
...
Flags: 0x4, CPU Version: 4
Tested in bpf-unknown-none.
include/ChangeLog:
2023-07-30 Jose E. Marchesi <jose.marchesi@oracle.com>
* elf/bpf.h (EF_BPF_CPUVER): Define.
* opcode/bpf.h (BPF_XBPF): Change from 0xf to 0xff so it fits in
EF_BPF_CPUVER.
binutils/ChangeLog:
2023-07-30 Jose E. Marchesi <jose.marchesi@oracle.com>
* readelf.c (get_machine_flags): Recognize and pretty print BPF
machine flags.
opcodes/ChangeLog:
2023-07-30 Jose E. Marchesi <jose.marchesi@oracle.com>
* bpf-dis.c: Initialize asm_bpf_version to -1.
(print_insn_bpf): Set BPF ISA version from the cpu version ELF
header flags if no explicit version set in the command line.
* disassemble.c (disassemble_init_for_target): Remove unused code.
gas/ChangeLog:
2023-07-30 Jose E. Marchesi <jose.marchesi@oracle.com>
* config/tc-bpf.h (elf_tc_final_processing): Define.
* config/tc-bpf.c (bpf_elf_final_processing): New function.
This patch adds support for the BPF V4 ISA byte swap instructions to
opcodes, assembler and disassembler.
Tested in bpf-unknown-none.
include/ChangeLog:
2023-07-24 Jose E. Marchesi <jose.marchesi@oracle.com>
* opcode/bpf.h (BPF_IMM32_BSWAP16): Define.
(BPF_IMM32_BSWAP32): Likewise.
(BPF_IMM32_BSWAP64): Likewise.
(enum bpf_insn_id): New entries BPF_INSN_BSWAP{16,32,64}.
opcodes/ChangeLog:
2023-07-24 Jose E. Marchesi <jose.marchesi@oracle.com>
* bpf-opc.c (bpf_opcodes): Add entries for the BSWAP*
instructions.
gas/ChangeLog:
2023-07-24 Jose E. Marchesi <jose.marchesi@oracle.com>
* doc/c-bpf.texi (BPF Instructions): Document BSWAP* instructions.
* testsuite/gas/bpf/alu.s: Test BSWAP{16,32,64} instructions.
* testsuite/gas/bpf/alu.d: Likewise.
* testsuite/gas/bpf/alu-be.d: Likewise.
* testsuite/gas/bpf/alu-pseudoc.s: Likewise.
* testsuite/gas/bpf/alu-pseudoc.d: Likewise.
* testsuite/gas/bpf/alu-be-pseudoc.d: Likewise.
This patch adds support for the V4 BPF instruction jal/gotol, which is
like ja/goto but it supports a signed 32-bit PC-relative (in number of
64-bit words minus one) target operand instead of the 16-bit signed
operand of the other instruction. This greatly increases the jump
range in BPF programs.
Tested in bpf-unkown-none.
bfd/ChangeLog:
2023-07-24 Jose E. Marchesi <jose.marchesi@oracle.com>
* reloc.c: New reloc BFD_RELOC_BPF_DISPCALL32.
* elf64-bpf.c (bpf_reloc_type_lookup): Handle the new reloc.
* libbfd.h (bfd_reloc_code_real_names): Regenerate.
gas/ChangeLog:
2023-07-24 Jose E. Marchesi <jose.marchesi@oracle.com>
* config/tc-bpf.c (struct bpf_insn): New field `id'.
(md_assemble): Save the ids of successfully parsed instructions
and use the new BFD_RELOC_BPF_DISPCALL32 whenever appropriate.
(md_apply_fix): Adapt to the new BFD reloc.
* testsuite/gas/bpf/jump.s: Test JAL.
* testsuite/gas/bpf/jump.d: Likewise.
* testsuite/gas/bpf/jump-pseudoc.d: Likewise.
* testsuite/gas/bpf/jump-be.d: Likewise.
* testsuite/gas/bpf/jump-be-pseudoc.d: Likewise.
* doc/c-bpf.texi (BPF Instructions): Document new instruction
jal/gotol.
Document new operand type disp32.
include/ChangeLog:
2023-07-24 Jose E. Marchesi <jose.marchesi@oracle.com>
* opcode/bpf.h (enum bpf_insn_id): Add entry BPF_INSN_JAL.
(enum bpf_insn_id): Remove spurious entry BPF_INSN_CALLI.
opcodes/ChangeLog:
2023-07-23 Jose E. Marchesi <jose.marchesi@oracle.com>
* bpf-opc.c (bpf_opcodes): Add entry for jal.
This commit adds the signed load to register (ldxs*) instructions
introduced in the BPF ISA version 4, including opcodes and assembler
tests.
Tested in bpf-unknown-none.
include/ChangeLog:
2023-07-21 Jose E. Marchesi <jose.marchesi@oracle.com>
* opcode/bpf.h (enum bpf_insn_id): Add entries for signed load
instructions.
(BPF_MODE_SMEM): Define.
opcodes/ChangeLog:
2023-07-21 Jose E. Marchesi <jose.marchesi@oracle.com>
* bpf-opc.c (bpf_opcodes): Add entries for LDXS{B,W,H,DW}
instructions.
gas/ChangeLog:
2023-07-21 Jose E. Marchesi <jose.marchesi@oracle.com>
* testsuite/gas/bpf/mem.s: Add signed load instructions.
* testsuite/gas/bpf/mem-pseudoc.s: Likewise.
* testsuite/gas/bpf/mem.d: Likewise.
* testsuite/gas/bpf/mem-pseudoc.d: Likewise.
* testsuite/gas/bpf/mem-be.d: Likewise.
* doc/c-bpf.texi (BPF Instructions): Document the signed load
instructions.
This commit adds the signed register move (movs) instructions
introduced in the BPF ISA version 4, including opcodes and assembler
tests.
Tested in bpf-unknown-none.
include/ChangeLog:
2023-07-21 Jose E. Marchesi <jose.marchesi@oracle.com>
* opcode/bpf.h (BPF_OFFSET16_MOVS8): Define.
(BPF_OFFSET16_MOVS16): Likewise.
(BPF_OFFSET16_MOVS32): Likewise.
(enum bpf_insn_id): Add entries for MOVS{8,16,32}R and
MOVS32{8,16,32}R.
opcodes/ChangeLog:
2023-07-21 Jose E. Marchesi <jose.marchesi@oracle.com>
* bpf-opc.c (bpf_opcodes): Add entries for MOVS{8,16,32}R and
MOVS32{8,16,32}R instructions. and MOVS32I instructions.
gas/ChangeLog:
2023-07-21 Jose E. Marchesi <jose.marchesi@oracle.com>
* testsuite/gas/bpf/alu.s: Test movs instructions.
* testsuite/gas/bpf/alu-pseudoc.s: Likewise.
* testsuite/gas/bpf/alu32.s: Likewise for movs32 instruction.
* testsuite/gas/bpf/alu32-pseudoc.s: Likewise.
* testsuite/gas/bpf/alu.d: Add expected results.
* testsuite/gas/bpf/alu32.d: Likewise.
* testsuite/gas/bpf/alu-be.d: Likewise.
* testsuite/gas/bpf/alu32-be.d: Likewise.
* testsuite/gas/bpf/alu-pseudoc.d: Likewise.
* testsuite/gas/bpf/alu32-pseudoc.d: Likewise.
* testsuite/gas/bpf/alu-be-pseudoc.d: Likewise.
* testsuite/gas/bpf/alu32-be-pseudoc.d: Likewise.
CGEN is cool, but the BPF architecture is simply too bizarre for it.
The weird way of BPF to handle endianness in instruction encoding, the
weird C-like alternative assembly syntax, the weird abuse of
multi-byte (or infra-byte) instruction fields as opcodes, the unusual
presence of opcodes beyond the first 32-bits of some instructions, are
all examples of what makes it a PITA to continue using CGEN for this
port. The bpf.cpu file is becoming so complex and so nested with
p-macros that it is very difficult to read, and quite challenging to
update. Also, every time we are forced to change something in CGEN to
accommodate BPF requirements (which is often) we have to do extensive
testing to make sure we do not break any other target using CGEN.
This is getting un-maintenable.
So I have decided to bite the bullet and revamp/rewrite the port so it
no longer uses CGEN. Overall, this involved:
* To remove the cpu/bpf.{cpu,opc} descriptions.
* To remove the CGEN generated files.
* To replace the CGEN generated opcodes table with a new hand-written
opcodes table for BPF.
* To replace the CGEN generated disassembler wih a new disassembler
that uses the new opcodes.
* To replace the CGEN generated assembler with a new assembler that uses the
new opcodes.
* To replace the CGEN generated simulator with a new simulator that uses the
new opcodes. [This is pushed in GDB in another patch.]
* To adapt the build systems to the new situation.
Additionally, this patch introduces some extensions and improvements:
* A new BPF relocation BPF_RELOC_BPF_DISP16 plus corresponding ELF
relocation R_BPF_GNU_64_16 are added to the BPF BFD port. These
relocations are used for section-relative 16-bit offsets used in
load/store instructions.
* The disassembler now has support for the "pseudo-c" assembly syntax of
BPF. What dialect to use when disassembling is controlled by a command
line option.
* The disassembler now has support for dumping instruction immediates in
either octal, hexadecimal or decimal. The used output base is controlled
by a new command-line option.
* The GAS BPF test suite has been re-structured and expanded in order to
test the disassembler pseudoc syntax support. Minor bugs have been also
fixed there. The assembler generic tests that were disabled for bpf-*-*
targets due to the previous implementation of pseudoc syntax are now
re-enabled. Additional tests have been added to test the new features of
the assembler. .dump files are no longer used.
* The linker BPF test suite has been adapted to the command line options
used by the new disassembler.
The result is very satisfactory. This patchs adds 3448 lines of code
and removes 10542 lines of code.
Tested in:
* Target bpf-unknown-none with 64-bit little-endian host and 32-bit
little-endian host.
* Target x86-64-linux-gnu with --enable-targets=all
Note that I have not tested in a big-endian host yet. I will do so
once this lands upstream so I can use the GCC compiler farm.
I have not included ChangeLog entries in this patch: these would be
massive and not very useful, considering this is pretty much a rewrite
of the port. I beg the indulgence of the global maintainers.
