The following table shows which [eBPF instructions](https://github.com/dthaler/ebpf-docs/blob/update/isa/kernel.org/instruction-set.rst) are currently supported by PREVAIL, uBPF, and bpf2c, and which bpf_conformance test covers it.
| opcode | src | imm | description | PREVAIL | uBPF | bpf2c | conformance |
|---|---|---|---|---|---|---|---|
| 0x00 | 0x0 | any | (additional immediate value) | Y | Y | Y | arsh32-high-shift |
| 0x04 | 0x0 | any | dst = (uint32_t)(dst + imm) | Y | Y | Y | add |
| 0x05 | 0x0 | 0x00 | goto +offset | Y | Y | Y | exit-not-last |
| 0x07 | 0x0 | any | dst += imm | Y | Y | Y | add64 |
| 0x0c | any | 0x00 | dst = (uint32_t)(dst + src) | Y | Y | Y | add |
| 0x0f | any | 0x00 | dst += src | Y | Y | Y | alu64-arith |
| 0x14 | 0x0 | any | dst = (uint32_t)(dst - imm) | Y | Y | Y | alu-arith |
| 0x15 | 0x0 | any | if dst == imm goto +offset | Y | Y | Y | jeq-imm |
| 0x16 | 0x0 | any | if (uint32_t)dst == imm goto +offset | Y | Y | Y | jeq32-imm |
| 0x17 | 0x0 | any | dst -= imm | Y | Y | Y | alu64-arith |
| 0x18 | 0x0 | any | dst = imm64 | Y | Y | Y | lddw |
| 0x18 | 0x1 | any | dst = map_by_fd(imm) | no | no | no | ??? |
| 0x18 | 0x2 | any | dst = mva(map_by_fd(imm)) + next_imm | no | no | no | ??? |
| 0x18 | 0x3 | any | dst = variable_addr(imm) | no | no | no | ??? |
| 0x18 | 0x4 | any | dst = code_addr(imm) | no | no | no | ??? |
| 0x18 | 0x5 | any | dst = map_by_idx(imm) | no | no | no | ??? |
| 0x18 | 0x6 | any | dst = mva(map_by_idx(imm)) + next_imm | no | no | no | ??? |
| 0x1c | any | 0x00 | dst = (uint32_t)(dst - src) | Y | Y | Y | alu-arith |
| 0x1d | any | 0x00 | if dst == src goto +offset | Y | Y | Y | jeq-reg |
| 0x1e | any | 0x00 | if (uint32_t)dst == (uint32_t)src goto +offset | Y | Y | Y | jeq32-reg |
| 0x1f | any | 0x00 | dst -= src | Y | Y | Y | alu64-arith |
| 0x20 | any | any | (deprecated, implementation-specific) | no | no | no | (none) |
| 0x24 | 0x0 | any | dst = (uint32_t)(dst * imm) | Y | Y | Y | mul32-imm |
| 0x25 | 0x0 | any | if dst > imm goto +offset | Y | Y | Y | jgt-imm |
| 0x26 | 0x0 | any | if (uint32_t)dst > imm goto +offset | Y | Y | Y | jgt32-imm |
| 0x27 | 0x0 | any | dst *= imm | Y | Y | Y | mul64-imm |
| 0x28 | any | any | (deprecated, implementation-specific) | no | no | no | (none) |
| 0x2c | any | 0x00 | dst = (uint32_t)(dst * src) | Y | Y | Y | mul32-reg |
| 0x2d | any | 0x00 | if dst > src goto +offset | Y | Y | Y | jgt-reg |
| 0x2e | any | 0x00 | if (uint32_t)dst > (uint32_t)src goto +offset | Y | Y | Y | jgt32-reg |
| 0x2f | any | 0x00 | dst *= src | Y | Y | Y | mul64-reg |
| 0x30 | any | any | (deprecated, implementation-specific) | no | no | no | (none) |
| 0x34 | 0x0 | any | dst = (uint32_t)((imm != 0) ? (dst / imm) : 0) | Y | Y | Y | alu-arith |
| 0x35 | 0x0 | any | if dst >= imm goto +offset | Y | Y | Y | jge-imm |
| 0x36 | 0x0 | any | if (uint32_t)dst >= imm goto +offset | Y | Y | Y | jge32-imm |
| 0x37 | 0x0 | any | dst = (imm != 0) ? (dst / imm) : 0 | Y | Y | Y | alu64-arith |
| 0x38 | any | any | (deprecated, implementation-specific) | no | no | no | (none) |
| 0x3c | any | 0x00 | dst = (uint32_t)((imm != 0) ? (dst / src) : 0) | Y | Y | Y | alu-arith |
| 0x3d | any | 0x00 | if dst >= src goto +offset | Y | Y | Y | prime |
| 0x3e | any | 0x00 | if (uint32_t)dst >= (uint32_t)src goto +offset | Y | Y | Y | jge32-reg |
| 0x3f | any | 0x00 | dst = (src !+ 0) ? (dst / src) : 0 | Y | Y | Y | alu64-arith |
| 0x40 | any | any | (deprecated, implementation-specific) | no | no | no | (none) |
| 0x44 | 0x0 | any | dst = (uint32_t)(dst | imm) | Y | Y | Y | alu-bit |
| 0x45 | 0x0 | any | if dst & imm goto +offset | Y | Y | Y | jset-imm |
| 0x46 | 0x0 | any | if (uint32_t)dst & imm goto +offset | Y | Y | Y | jset32-imm |
| 0x47 | 0x0 | any | dst |= imm | Y | Y | Y | alu64-bit |
| 0x48 | any | any | (deprecated, implementation-specific) | no | no | no | (none) |
| 0x4c | any | 0x00 | dst = (uint32_t)(dst | src) | Y | Y | Y | alu-bit |
| 0x4d | any | 0x00 | if dst & src goto +offset | Y | Y | Y | jset-reg |
| 0x4e | any | 0x00 | if (uint32_t)dst & (uint32_t)src goto +offset | Y | Y | Y | jset32-reg |
| 0x4f | any | 0x00 | dst |= src | Y | Y | Y | alu64-bit |
| 0x50 | any | any | (deprecated, implementation-specific) | no | no | no | (none) |
| 0x54 | 0x0 | any | dst = (uint32_t)(dst & imm) | Y | Y | Y | alu-bit |
| 0x55 | 0x0 | any | if dst != imm goto +offset | Y | Y | Y | alu-arith |
| 0x56 | 0x0 | any | if (uint32_t)dst != imm goto +offset | Y | Y | Y | jne32-imm |
| 0x57 | 0x0 | any | dst &= imm | Y | Y | Y | alu64-bit |
| 0x58 | any | any | (deprecated, implementation-specific) | no | no | no | (none) |
| 0x5c | any | 0x00 | dst = (uint32_t)(dst & src) | Y | Y | Y | alu-bit |
| 0x5d | any | 0x00 | if dst != src goto +offset | Y | Y | Y | jne-reg |
| 0x5e | any | 0x00 | if (uint32_t)dst != (uint32_t)src goto +offset | Y | Y | Y | jne32-reg |
| 0x5f | any | 0x00 | dst &= src | Y | Y | Y | alu64-bit |
| 0x61 | any | 0x00 | dst = *(uint32_t *)(src + offset) | Y | Y | Y | ldxw |
| 0x62 | 0x0 | any | *(uint32_t *)(dst + offset) = imm | Y | Y | Y | stw |
| 0x63 | any | 0x00 | *(uint32_t *)(dst + offset) = src | Y | Y | Y | stxw |
| 0x64 | 0x0 | any | dst = (uint32_t)(dst << imm) | Y | Y | Y | alu-bit |
| 0x65 | 0x0 | any | if dst s> imm goto +offset | Y | Y | Y | jsgt-imm |
| 0x66 | 0x0 | any | if (int32_t)dst s> (int32_t)imm goto +offset | Y | Y | Y | jsgt32-imm |
| 0x67 | 0x0 | any | dst <<= imm | Y | Y | Y | alu64-bit |
| 0x69 | any | 0x00 | dst = *(uint16_t *)(src + offset) | Y | Y | Y | ldxh |
| 0x6a | 0x0 | any | *(uint16_t *)(dst + offset) = imm | Y | Y | Y | sth |
| 0x6b | any | 0x00 | *(uint16_t *)(dst + offset) = src | Y | Y | Y | stxh |
| 0x6c | any | 0x00 | dst = (uint32_t)(dst << src) | Y | Y | Y | alu-bit |
| 0x6d | any | 0x00 | if dst s> src goto +offset | Y | Y | Y | jsgt-reg |
| 0x6e | any | 0x00 | if (int32_t)dst s> (int32_t)src goto +offset | Y | Y | Y | jsgt32-reg |
| 0x6f | any | 0x00 | dst <<= src | Y | Y | Y | lsh-reg |
| 0x71 | any | 0x00 | dst = *(uint8_t *)(src + offset) | Y | Y | Y | ldxb |
| 0x72 | 0x0 | any | *(uint8_t *)(dst + offset) = imm | Y | Y | Y | stb |
| 0x73 | any | 0x00 | *(uint8_t *)(dst + offset) = src | Y | Y | Y | stxb |
| 0x74 | 0x0 | any | dst = (uint32_t)(dst >> imm) | Y | Y | Y | rsh32 |
| 0x75 | 0x0 | any | if dst s>= imm goto +offset | Y | Y | Y | jsge-imm |
| 0x76 | 0x0 | any | if (int32_t)dst s>= (int32_t)imm goto +offset | Y | Y | Y | jsge32-imm |
| 0x77 | 0x0 | any | dst >>= imm | Y | Y | Y | alu64-bit |
| 0x79 | any | 0x00 | dst = *(uint64_t *)(src + offset) | Y | Y | Y | ldxdw |
| 0x7a | 0x0 | any | *(uint64_t *)(dst + offset) = imm | Y | Y | Y | stdw |
| 0x7b | any | 0x00 | *(uint64_t *)(dst + offset) = src | Y | Y | Y | stxdw |
| 0x7c | any | 0x00 | dst = (uint32_t)(dst >> src) | Y | Y | Y | alu-bit |
| 0x7d | any | 0x00 | if dst s>= src goto +offset | Y | Y | Y | jsge-reg |
| 0x7e | any | 0x00 | if (int32_t)dst s>= (int32_t)src goto +offset | Y | Y | Y | jsge32-reg |
| 0x7f | any | 0x00 | dst >>= src | Y | Y | Y | rsh-reg |
| 0x84 | 0x0 | 0x00 | dst = (uint32_t)-dst | Y | Y | Y | neg |
| 0x85 | 0x0 | any | call helper function imm | Y | Y | Y | call_unwind_fail |
| 0x85 | 0x1 | any | call PC += offset | no | no | no | call_local |
| 0x85 | 0x2 | any | call runtime function imm | no | no | no | ??? |
| 0x87 | 0x0 | 0x00 | dst = -dst | Y | Y | Y | neg64 |
| 0x94 | 0x0 | any | dst = (uint32_t)((imm != 0) ? (dst % imm) : dst) | Y | Y | Y | mod |
| 0x95 | 0x0 | 0x00 | return | Y | Y | Y | exit |
| 0x97 | 0x0 | any | dst = (imm != 0) ? (dst % imm) : dst | Y | Y | Y | mod64 |
| 0x9c | any | 0x00 | dst = (uint32_t)((src != 0) ? (dst % src) : dst) | Y | Y | Y | mod |
| 0x9f | any | 0x00 | dst = (src != 0) ? (dst % src) : dst | Y | Y | Y | mod64 |
| 0xa4 | 0x0 | any | dst = (uint32_t)(dst ^ imm) | Y | Y | Y | alu-bit |
| 0xa5 | 0x0 | any | if dst < imm goto +offset | Y | Y | Y | jlt-imm |
| 0xa6 | 0x0 | any | if (uint32_t)dst < imm goto +offset | Y | Y | Y | jlt32-imm |
| 0xa7 | 0x0 | any | dst ^= imm | Y | Y | Y | alu64-bit |
| 0xac | any | 0x00 | dst = (uint32_t)(dst ^ src) | Y | Y | Y | alu-bit |
| 0xad | any | 0x00 | if dst < src goto +offset | Y | Y | Y | jlt-reg |
| 0xae | any | 0x00 | if (uint32_t)dst < (uint32_t)src goto +offset | Y | Y | Y | jlt32-reg |
| 0xaf | any | 0x00 | dst ^= src | Y | Y | Y | alu64-bit |
| 0xb4 | 0x0 | any | dst = (uint32_t) imm | Y | Y | Y | mov |
| 0xb5 | 0x0 | any | if dst <= imm goto +offset | Y | Y | Y | jle-imm |
| 0xb6 | 0x0 | any | if (uint32_t)dst <= imm goto +offset | Y | Y | Y | jle32-imm |
| 0xb7 | 0x0 | any | dst = imm | Y | Y | Y | mov64-sign-extend |
| 0xbc | any | 0x00 | dst = (uint32_t) src | Y | Y | Y | mov |
| 0xbd | any | 0x00 | if dst <= src goto +offset | Y | Y | Y | jle-reg |
| 0xbe | any | 0x00 | if (uint32_t)dst <= (uint32_t)src goto +offset | Y | Y | Y | jle32-reg |
| 0xbf | any | 0x00 | dst = src | Y | Y | Y | ldxb-all |
| 0xc3 | any | 0x00 | lock *(uint32_t *)(dst + offset) += src | no | no | Y | lock_add32 |
| 0xc3 | any | 0x01 | lock: *(uint32_t *)(dst + offset) += src src = *(uint32_t *)(dst + offset) |
no | no | Y | lock_fetch_add32 |
| 0xc3 | any | 0x40 | *(uint32_t *)(dst + offset) |= src | no | no | Y | lock_or32 |
| 0xc3 | any | 0x41 | lock: *(uint32_t *)(dst + offset) |= src src = *(uint32_t *)(dst + offset) |
no | no | Y | lock_fetch_or32 |
| 0xc3 | any | 0x50 | *(uint32_t *)(dst + offset) &= src | no | no | Y | lock_and32 |
| 0xc3 | any | 0x51 | lock: *(uint32_t *)(dst + offset) &= src src = *(uint32_t *)(dst + offset) |
no | no | Y | lock_fetch_and32 |
| 0xc3 | any | 0xa0 | *(uint32_t *)(dst + offset) ^= src | no | no | Y | lock_xor32 |
| 0xc3 | any | 0xa1 | lock: *(uint32_t *)(dst + offset) ^= src src = *(uint32_t *)(dst + offset) |
no | no | Y | lock_fetch_xor32 |
| 0xc3 | any | 0xe1 | lock: temp = *(uint32_t *)(dst + offset) *(uint32_t *)(dst + offset) = src src = temp |
no | no | Y | lock_xchg32 |
| 0xc3 | any | 0xf1 | lock: temp = *(uint32_t *)(dst + offset) if *(uint32_t)(dst + offset) == R0 *(uint32_t)(dst + offset) = src R0 = temp |
no | no | Y | lock_cmpxchg32 |
| 0xc4 | 0x0 | any | dst = (uint32_t)(dst s>> imm) | Y | Y | Y | arsh |
| 0xc5 | 0x0 | any | if dst s< imm goto +offset | Y | Y | Y | jslt-imm |
| 0xc6 | 0x0 | any | if (int32_t)dst s< (int32_t)imm goto +offset | Y | Y | Y | jslt32-imm |
| 0xc7 | 0x0 | any | dst s>>= imm | Y | Y | Y | arsh64 |
| 0xcc | any | 0x00 | dst = (uint32_t)(dst s>> src) | Y | Y | Y | arsh-reg |
| 0xcd | any | 0x00 | if dst s< src goto +offset | Y | Y | Y | jslt-reg |
| 0xce | any | 0x00 | if (int32_t)dst s< (int32_t)src goto +offset | Y | Y | Y | jslt32-reg |
| 0xcf | any | 0x00 | dst s>>= src | Y | Y | Y | arsh64 |
| 0xd4 | 0x0 | 0x10 | dst = htole16(dst) | Y | Y | Y | le16 |
| 0xd4 | 0x0 | 0x20 | dst = htole32(dst) | Y | Y | Y | le32 |
| 0xd4 | 0x0 | 0x40 | dst = htole64(dst) | Y | Y | Y | le64 |
| 0xd5 | 0x0 | any | if dst s<= imm goto +offset | Y | Y | Y | jsle-imm |
| 0xd6 | 0x0 | any | if (int32_t)dst s<= (int32_t)imm goto +offset | Y | Y | Y | jsle32-imm |
| 0xdb | any | 0x00 | lock *(uint64_t *)(dst + offset) += src | no | no | Y | lock_add |
| 0xdb | any | 0x01 | lock: *(uint64_t *)(dst + offset) += src src = *(uint64_t *)(dst + offset) |
no | no | Y | lock_fetch_add |
| 0xdb | any | 0x40 | *(uint64_t *)(dst + offset) |= src | no | no | Y | lock_or |
| 0xdb | any | 0x41 | lock: *(uint64_t *)(dst + offset) |= src lock src = *(uint64_t *)(dst + offset) |
no | no | Y | lock_fetch_or |
| 0xdb | any | 0x50 | *(uint64_t *)(dst + offset) &= src | no | no | Y | lock_and |
| 0xdb | any | 0x51 | lock: *(uint64_t *)(dst + offset) &= src src = *(uint64_t *)(dst + offset) |
no | no | Y | lock_fetch_and |
| 0xdb | any | 0xa0 | *(uint64_t *)(dst + offset) ^= src | no | no | Y | lock_xor |
| 0xdb | any | 0xa1 | lock: *(uint64_t *)(dst + offset) ^= src src = *(uint64_t *)(dst + offset) |
no | no | Y | lock_fetch_xor |
| 0xdb | any | 0xe1 | lock: temp = *(uint64_t *)(dst + offset) *(uint64_t *)(dst + offset) = src src = temp |
no | no | Y | lock_xchg |
| 0xdb | any | 0xf1 | lock: temp = *(uint64_t *)(dst + offset) if *(uint64_t)(dst + offset) == R0 *(uint64_t)(dst + offset) = src R0 = temp |
no | no | Y | lock_cmpxchg |
| 0xdc | 0x0 | 0x10 | dst = htobe16(dst) | Y | Y | Y | be16 |
| 0xdc | 0x0 | 0x20 | dst = htobe32(dst) | Y | Y | Y | be32 |
| 0xdc | 0x0 | 0x40 | dst = htobe64(dst) | Y | Y | Y | be64 |
| 0xdd | any | 0x00 | if dst s<= src goto +offset | Y | Y | Y | jsle-reg |
| 0xde | any | 0x00 | if (int32_t)dst s<= (int32_t)src goto +offset | Y | Y | Y | jsle32-reg |
Some takeaways:
- Some ldx instruction conformance issues still exist in the PREVAIL verifier, where instructions fail verification that shouldn't. This is not a security issue, it might simply prevent some valid programs from being verified (vbpf/ebpf-verifier#420).
- Atomic instructions are not supported by any of the components, though this is not a major problem as they will not be generated by clang when an older "cpu version" is specified on the command line.
- The conformance suite does not support most 64-bit immediate instructions (Alan-Jowett/bpf_conformance#59).