fold/third_party/ghidra-decompiler/specs/x86/x86borland.cspec
trvon c08081a016
feat: vendor x86-64 + 32-bit SLEIGH; precise SSA def-use; write-loop FP guard
Unlocks the x86 family end-to-end and makes the write-loop detector precise
enough for statically-linked binaries.

x86 SLEIGH:
- Vendor Ghidra's x86 language specs (specs/x86, x86:LE:64:default + :32:default);
  add x86-64/x86 .sla build targets. archSpecFor maps x86/64 + x86/32.
- ghidra_lifter: set the x86-64 decode context (longMode/addrsize/opsize) in the
  raw path, and bound decompiler flow at the function end (0xC3 tail fill) so
  variable-length x86 does not run away into zero padding.

Precise SSA def-use (benefits all arches):
- ir::pcode::PcodeOp gains in_def (defining-op index per input); the SSA lifter
  records real def-use. summarizePointerWrites now resolves the store-address
  base via def-use instead of a last-write heuristic — essential on x86 where
  arg registers are reused as scratch (RAX) and sub-registers are written (SIL).
- paramIndexOf is arch-aware (AArch64 x0–x7; SysV x86-64 RDI/RSI/RDX/RCX/R8/R9).

Precision (the key fix at scale):
- A copy bounded by a size *parameter* (memcpy-like `for i<n`) is suppressed:
  if the loop index is `<`-compared against a pure parameter input, the function
  is size-bounded and not flagged. baby_bof's decode_base64 bounds on
  strlen(input) (a computed value, not a param) so it still fires. This cut a
  statically-linked x86-64 binary from 101 findings (≈100 glibc/libstdc++ FPs)
  to 1 — the real decode_base64 → 264-byte overflow.

Perf + reach:
- Cache the pre-pass SSA lift and reuse it in the main pass (re-lifting only the
  few callers of a write-loop callee that need the injected prototype).
- Give whole-binary r2 analysis a generous timeout (FOLD_R2_ANALYSIS_TIMEOUT_MS,
  default 120s) so large static binaries actually analyze (the 3s per-command
  watchdog left them with an empty function list).

Validated: decode_base64 overflow fires on x86-64 (index_amd64.cgi) and AArch64
(index_nocanary.cgi); AArch64 corpus BOF counts unchanged (3/1/1); x86-64 static
FP 101→1. Unit: test_pcode_summary +x86-64 case (9 assertions). meson test 77/77.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-01 10:34:28 -04:00

150 lines
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XML

<?xml version="1.0" encoding="UTF-8"?>
<compiler_spec>
<data_organization>
<absolute_max_alignment value="0" />
<machine_alignment value="2" />
<default_alignment value="1" />
<default_pointer_alignment value="4" />
<pointer_size value="4" />
<wchar_size value="4" />
<short_size value="2" />
<integer_size value="4" />
<long_size value="4" />
<long_long_size value="8" />
<float_size value="4" />
<double_size value="8" />
<long_double_size value="10" /> <!-- aligned-length=12 -->
<size_alignment_map>
<entry size="1" alignment="1" />
<entry size="2" alignment="2" />
<entry size="4" alignment="4" />
<entry size="8" alignment="4" />
</size_alignment_map>
</data_organization>
<global>
<range space="ram"/>
</global>
<stackpointer register="ESP" space="ram"/>
<default_proto>
<prototype name="__fastcall" extrapop="unknown" stackshift="4">
<input>
<pentry minsize="1" maxsize="4">
<register name="EAX"/>
</pentry>
<pentry minsize="1" maxsize="4">
<register name="EDX"/>
</pentry>
<pentry minsize="1" maxsize="4">
<register name="ECX"/>
</pentry>
<pentry minsize="1" maxsize="500" align="4">
<addr offset="4" space="stack"/>
</pentry>
</input>
<output>
<pentry minsize="1" maxsize="4">
<register name="EAX"/>
</pentry>
</output>
<unaffected>
<register name="ESP"/>
<register name="EBP"/>
<register name="ESI"/>
<register name="EDI"/>
<register name="EBX"/>
</unaffected>
<killedbycall>
<register name="ECX"/>
<register name="EDX"/>
</killedbycall>
</prototype>
</default_proto>
<prototype name="__stdcall" extrapop="unknown" stackshift="4">
<input>
<pentry minsize="1" maxsize="500" align="4">
<addr offset="4" space="stack"/>
</pentry>
</input>
<output>
<pentry minsize="1" maxsize="4">
<register name="EAX"/>
</pentry>
</output>
<unaffected>
<varnode space="ram" offset="0" size="4"/>
<register name="ESP"/>
<register name="EBP"/>
<register name="ESI"/>
<register name="EDI"/>
<register name="EBX"/>
<register name="DF"/>
</unaffected>
<killedbycall>
<register name="ECX"/>
<register name="EDX"/>
</killedbycall>
<likelytrash>
<register name="ECX"/>
</likelytrash>
</prototype>
<prototype name="__cdecl" extrapop="4" stackshift="4">
<input>
<pentry minsize="1" maxsize="500" align="4">
<addr offset="4" space="stack"/>
</pentry>
</input>
<output>
<pentry minsize="1" maxsize="4">
<register name="EAX"/>
</pentry>
</output>
<unaffected>
<varnode space="ram" offset="0" size="4"/>
<register name="ESP"/>
<register name="EBP"/>
<register name="ESI"/>
<register name="EDI"/>
<register name="EBX"/>
<register name="DF"/>
</unaffected>
<killedbycall>
<register name="ECX"/>
<register name="EDX"/>
</killedbycall>
<likelytrash>
<register name="ECX"/>
</likelytrash>
</prototype>
<prototype name="__thiscall" extrapop="4" stackshift="4">
<input>
<pentry minsize="1" maxsize="500" align="4">
<addr offset="4" space="stack"/>
</pentry>
</input>
<output>
<pentry minsize="1" maxsize="4">
<register name="EAX"/>
</pentry>
</output>
<unaffected>
<register name="ESP"/>
<register name="EBP"/>
<register name="ESI"/>
<register name="EDI"/>
<register name="EBX"/>
</unaffected>
<killedbycall>
<register name="ECX"/>
<register name="EDX"/>
</killedbycall>
<likelytrash>
<register name="EAX"/>
</likelytrash>
</prototype>
<resolveprototype name="__stdcall/__fastcall">
<model name="__stdcall"/> <!-- The default case -->
<model name="__fastcall"/>
</resolveprototype>
<eval_current_prototype name="__stdcall/__fastcall"/>
</compiler_spec>