On 2/27/19 12:50 PM, Jiong Wang wrote:
> Like the other load/store instructions, "w" register is prefered when
> disassembling BPF_STX | BPF_W | BPF_XADD under sub-register mode.
>
> Signed-off-by: Jiong Wang <jiong.wang@xxxxxxxxxxxxx>
> ---
> lib/Target/BPF/Disassembler/BPFDisassembler.cpp | 3 ++-
> test/MC/BPF/load-store-32.s | 3 +++
> 2 files changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/lib/Target/BPF/Disassembler/BPFDisassembler.cpp b/lib/Target/BPF/Disassembler/BPFDisassembler.cpp
> index ed09e44..c5be7cb 100644
> --- a/lib/Target/BPF/Disassembler/BPFDisassembler.cpp
> +++ b/lib/Target/BPF/Disassembler/BPFDisassembler.cpp
> @@ -171,9 +171,10 @@ DecodeStatus BPFDisassembler::getInstruction(MCInst &Instr, uint64_t &Size,
> if (Result == MCDisassembler::Fail) return MCDisassembler::Fail;
>
> uint8_t InstClass = getInstClass(Insn);
> + uint8_t InstMode = getInstMode(Insn);
> if ((InstClass == BPF_LDX || InstClass == BPF_STX) &&
> getInstSize(Insn) != BPF_DW &&
> - getInstMode(Insn) == BPF_MEM &&
> + (InstMode == BPF_MEM || InstMode == BPF_XADD) &&
> STI.getFeatureBits()[BPF::ALU32])
> Result = decodeInstruction(DecoderTableBPFALU3264, Instr, Insn, Address,
This change triggered the unit test MC/BPF/insn-unit.s failure.
Exit Code: 1
Command Output (stderr):
--
/data/users/yhs/work/llvm/test/MC/BPF/insn-unit.s:60:11: error: CHECK:
expected string not found in input
// CHECK: c3 92 10 00 00 00 00 00 lock *(u32 *)(r2 + 16) += r9
^
<stdin>:25:2: note: scanning from here
22: c3 92 10 00 00 00 00 00 lock *(u32 *)(r2 + 16) += w9
^
<stdin>:25:6: note: possible intended match here
22: c3 92 10 00 00 00 00 00 lock *(u32 *)(r2 + 16) += w9
^
probably objdump -mattr=+alu32 decoding issue.
> this, STI);
> diff --git a/test/MC/BPF/load-store-32.s b/test/MC/BPF/load-store-32.s
> index 73ed9fc..be576d2 100644
> --- a/test/MC/BPF/load-store-32.s
> +++ b/test/MC/BPF/load-store-32.s
> @@ -17,9 +17,12 @@
> *(u8 *)(r0 + 0) = w7 // BPF_STX | BPF_B
> *(u16 *)(r1 + 8) = w8 // BPF_STX | BPF_H
> *(u32 *)(r2 + 16) = w9 // BPF_STX | BPF_W
> + lock *(u32 *)(r2 + 16) += w9 // BPF_STX | BPF_W | BPF_XADD
> // CHECK-32: 73 70 00 00 00 00 00 00 *(u8 *)(r0 + 0) = w7
> // CHECK-32: 6b 81 08 00 00 00 00 00 *(u16 *)(r1 + 8) = w8
> // CHECK-32: 63 92 10 00 00 00 00 00 *(u32 *)(r2 + 16) = w9
> +// CHECK-32: c3 92 10 00 00 00 00 00 lock *(u32 *)(r2 + 16) += w9
> // CHECK: 73 70 00 00 00 00 00 00 *(u8 *)(r0 + 0) = r7
> // CHECK: 6b 81 08 00 00 00 00 00 *(u16 *)(r1 + 8) = r8
> // CHECK: 63 92 10 00 00 00 00 00 *(u32 *)(r2 + 16) = r9
> +// CHECK: c3 92 10 00 00 00 00 00 lock *(u32 *)(r2 + 16) += r9
>
