fix: LLIL OperationOperands undercounts (17 ops)#27
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The OperationOperands count table in Struct/BNLowLevelILInstruction.cs sized the per-instruction RawOperands[] array too small for 17 operations, so accessing the affected typed-accessor property threw IndexOutOfRangeException at runtime. The undercounts fell into groups: - SSA register/flag/stack ops omitted the version's second raw slot (ASSERT_SSA, FLAG_BIT_SSA, REG_SSA_PARTIAL, REG_STACK_ABS_SSA, REG_STACK_REL_SSA, SET_REG_SSA_PARTIAL, FORCE_VER_SSA, CALL_STACK_SSA) - Phi ops omitted the 2-slot dest SSA (FLAG_PHI, REG_PHI, REG_STACK_PHI) - Memory-version slots omitted (STORE_SSA destMem/srcMem, TAILCALL_SSA) - Two-slot operands (ASSERT sourceRegister+constraint, FLAG_BIT/FLAG_COND, INTRINSIC output-list+intrinsic+params) Counts verified 1:1 against lowlevelilinstruction.h/.cpp; an SSA register/flag/stack occupies two raw slots (value, version), and the phi source-list readers route through the native list API so the count need only cover the directly-indexed slots. No bogus accessors found.
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Problem
The
OperationOperandscount table inStruct/BNLowLevelILInstruction.cssizes each instruction'sRawOperands[]array. 17 entries undercounted their operands, so accessing the affected typed-accessor property threwIndexOutOfRangeExceptionat runtime.Root cause
Counts verified 1:1 against
lowlevelilinstruction.h/.cpp(s_instructionOperandUsage+ the per-opLowLevelILInstructionAccessorraw-index calls). Misses by group:An SSA register/flag/stack occupies two raw slots (value, version). The phi source-list readers route through the native list API rather than
RawOperands[], so the count need only cover the directly-indexed slots. No bogus accessors found (verified each C# index maps to a genuine C++ operand).Same systematic-miscount cluster as HLIL (PR #26); MLIL follows in a separate PR.
Changes
Struct/BNLowLevelILInstruction.cs: 17 count bumps, each with an operand-list comment.Verification
dotnet build -c Releaseclean.crash_audit_llil.py): NO OOB after the fix (was 17 OOB).MustGetExpressionsweep overcat.bndbLLIL, invokes each declared operand-accessor getter, asserts none throwsIndexOutOfRangeException.