LoongArch: BPF: Remove redundant zext jumping in move_imm()

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In move_imm(), when an immediate hits the 12-bit unsigned range, an
`ori rd, $zero, imm` instruction is emitted.

According to the manual, the `ori` instruction inherently performs a
logical or with zero-extended immediate operands against $zero, so the
upper 32 bits of the destination register `rd` are already 0.

However, the existing JIT code unconditionally executes `goto zext;`
after `ori`, forcing it to fallthrough into `emit_zext_32()` to clear
the upper 32 bits for 32-bit ALU operations.

Fix this redundancy by directly returning from the function inside the
`is_unsigned_imm12()` block.

Acked-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

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Tiezhu Yang 2026-08-17 22:07:24 +08:00 • committed by Huacai Chen

parent 434308885d

commit 32a5e3eaa0

1 changed files with 1 additions and 1 deletions

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arch/loongarch/net/bpf_jit.h

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