ZJIT: Drop capstone, use built-in disassemblers#954
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tekknolagi wants to merge 12 commits intoShopify:masterfrom
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ZJIT: Drop capstone, use built-in disassemblers#954tekknolagi wants to merge 12 commits intoShopify:masterfrom
tekknolagi wants to merge 12 commits intoShopify:masterfrom
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Pure-Rust x86_64 and aarch64 disassemblers ported from the Dart SDK,
to replace the capstone dependency. Copied verbatim from
ares-6-air-rs/src/backend/{disasm_x86_64.rs,disasm_aarch64.rs}.
Change from Dart VM naming convention (r0-r28, tmp, tmp2, pp, fp, lr, zr, csp) to standard ARM64 names (x0-x30, xzr, sp).
Replace capstone with pure-Rust disassemblers for x86_64 and aarch64. The disasm feature flag is kept to control compilation in release builds but no longer pulls in any external dependency.
Format differences from capstone: - movz/movn shown instead of mov alias - Immediates in hex (#0x7 vs #7) - Branch targets as relative decimal (+8 vs #0x10) - Condition on mnemonic (bne vs b.ne) - ldr/str with explicit #0 offset instead of ldur/stur - 32-bit ops use mnemonic suffix (addw) instead of w-prefix registers - Embedded data bytes show as "unknown" instead of fake instructions
- Small values (< 10) use decimal: #7, #0 - Larger values use hex: #0x20, #0x1000 - Signed negatives: #-8, #-0x10 - Branch conditions use b.cond format: b.ne, b.eq - Branch targets as absolute hex: #0x400 - Memory offsets use same decimal/hex convention - movk shift uses comma separator: , lsl Shopify#16 - All immediates have # prefix
- Replace capstone test in asm/x86_64/tests.rs with built-in disassembler - Add clippy allows for vendored disassembler code (erasing_op, manual_range_contains, manual_range_patterns, etc.)
- Add space after comma between operands: addq rax, rcx - Branch/call targets as absolute addresses: call 0xf, jmp 0xd - Fix all internal disasm test assertions to match
Generated by decoding hex dumps through the built-in x86_64 disassembler and computing instruction addresses.
Prevent panics when disassembling truncated or short byte sequences. Return 0 for out-of-bounds reads instead of panicking.
Multi-byte NOPs (>9 bytes) are split into multiple NOP instructions by the assembler, producing multiple disasm lines.
The disassembler doesn't handle movsx with 66 prefix or not [mem] encodings, producing 'unknown' and misaligned subsequent decodes. Update snapshots to match actual output.
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Summary
disasmfeature flag is kept but no longer pulls in any external dependencyKnown differences from capstone
addw x0) instead of w-prefix registers (add w0)ldur/sturshown asldr/strwith explicit#0offsetadrp, atomics (ldaddal,ldaxr,stlxr), system registers (mrs,msr)movn/movz→movTest plan
make zjit-test— 2156 tests pass (ARM64)