Like the other load/store instructions, "w" register is preferred when
disassembling BPF_STX | BPF_W | BPF_XADD.
v1 -> v2:
- Updated testcase insn-unit.s (Yonghong)
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
llvm-svn: 355127
JMP32 instructions has been added to eBPF ISA. They are 32-bit variants of
existing BPF conditional jump instructions, but the comparison happens on
low 32-bit sub-register only, therefore some unnecessary extensions could
be saved.
JMP32 instructions will only be available for -mcpu=v3. Host probe hook has
been updated accordingly.
JMP32 instructions will only be enabled in code-gen when -mattr=+alu32
enabled, meaning compiling the program using sub-register mode.
For JMP32 encoding, it is a new instruction class, and is using the
reserved eBPF class number 0x6.
This patch has been tested by compiling and running kernel bpf selftests
with JMP32 enabled.
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
llvm-svn: 353384
This patch test disassembler output for load/store instructions when
-mattr=+alu32 specified for which we want to use "w" register format.
Also, this patch extended the existing insn-unit.s and insn-unit-32.s to
make sure disassemblers for all other instructions are not affected.
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 325993
This patch adds new insn, "reg = be16/be32/be64 reg",
for bswap to little endian for big-endian target (bpfeb).
It also adds new insn for negation "reg = -reg".
Currently, for source code, e.g.,
b = -a
LLVM still prefers to generate:
b = 0 - a
But "reg = -reg" format can be used in assembly code.
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
llvm-svn: 314376
This patch adds instruction patterns for operations in BPF_ALU. After this,
assembler could recognize some 32-bit ALU statement. For example, those listed
int the unit test file.
Separate MOV patterns are unnecessary as MOV is ALU operation that could reuse
ALU encoding infrastructure, this patch removed those redundant patterns.
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Reviewed-by: Yonghong Song <yhs@fb.com>
llvm-svn: 313961