[AArch64][LFI] Consolidate LFI metadata into centralized type-safe mapping tables#5
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…pping tables Refactor the AArch64 Lightweight Fault Isolation (LFI) metadata TableGen architecture by moving all variant mapping relationships into explicit, centralized lookup tables inside AArch64LFI.td. This approach keeps core target files completely untouched by LFI mapping metadata. Instead of dynamically resolving base instruction names from subclass records, this design declares all mappings explicitly in centralized tables (LFIVariantTable, PairVariantTable, SIMDPostTable). This design guarantees 100% compile-time type safety; TableGen verifies that all mapped variant and base instructions are valid records, failing immediately at build-time if there are any typos. - Isolate LFI table entry structures (LFIVariantEntry, LFIPairVariantEntry, LFISIMDPostEntry) and LFIAddrMode constants into AArch64LFIInstrFormats.td. - Completely strip all LFI variant, pair, and SIMD metadata fields (HasLFIVariant, HasPairVariant, HasSIMDPost) from AArch64InstrFormats.td, leaving core formats focused strictly on memory layout properties for the MemInfoTable. - Introduce concise, type-safe helper multiclasses (LFIFamily, LFIPairFamily, LFIPrefetchFamily) in AArch64LFI.td to explicitly and cleanly declare all GPR, FPR, and Prefetch variant mappings. - Maintain type-safe SIMD post-index writeback scaling by mapping over 200 SIMD instructions via loops over structural family definitions in AArch64LFI.td. - Synchronize structure fields in AArch64MCLFIRewriter.cpp with TableGen's generated searchable primary keys.
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…lvm#207008) `Evaluate_DW_OP_convert` dereferenced `eval_ctx.dwarf_cu` (the `DWARFExpression` Delegate) whenever the operand DIE offset was non-zero, and unconditionally read `eval_ctx.stack.back()`. When a DWARF expression is evaluated without a DWARF unit (as the lldb-dwarf-expression-fuzzer does), two operand shapes crash: - `DW_OP_convert` with a non-zero offset calls `dwarf_cu->GetDIEBitSizeAndSign(...)` on a null Delegate. - `DW_OP_convert` with nothing on the stack reads the back of an empty vector. The unit test feeds both with `dwarf_cu == nullptr` and crashes: ``` [ RUN ] DWARFExpression.DW_OP_convert #2 SignalHandler(int, __siginfo*, void*) #4 DWARFExpression::Evaluate(...) #5 Evaluate(ArrayRef<unsigned char>, ...) ``` (SIGSEGV, the process aborts.) Bail out with an error when the stack is empty, and when a non-zero DIE offset is requested without a DWARF unit, instead of crashing. Extends `DWARFExpression.DW_OP_convert` with these two cases, which crash without the fix. --------- Co-authored-by: Michael Buch <michaelbuch12@gmail.com>
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Refactor the AArch64 Lightweight Fault Isolation (LFI) metadata TableGen
architecture by moving all variant mapping relationships into explicit,
centralized lookup tables inside AArch64LFI.td.
This approach keeps core target files completely untouched by LFI
mapping metadata. Instead of dynamically resolving base instruction
names from subclass records, this design declares all mappings
explicitly in centralized tables (LFIVariantTable, PairVariantTable,
SIMDPostTable). This design guarantees 100% compile-time type safety;
TableGen verifies that all mapped variant and base instructions are
valid records, failing immediately at build-time if there are any typos.
LFISIMDPostEntry) and LFIAddrMode constants into AArch64LFIInstrFormats.td.
HasPairVariant, HasSIMDPost) from AArch64InstrFormats.td, leaving core formats
focused strictly on memory layout properties for the MemInfoTable.
LFIPrefetchFamily) in AArch64LFI.td to explicitly and cleanly declare all GPR,
FPR, and Prefetch variant mappings.
instructions via loops over structural family definitions in AArch64LFI.td.
generated searchable primary keys.