synth_backend/
elf_builder.rs

1//! ELF (Executable and Linkable Format) Builder for ARM
2//!
3//! Generates ELF32 files for ARM Cortex-M targets
4
5use synth_core::Result;
6
7/// ELF file class
8#[derive(Debug, Clone, Copy, PartialEq, Eq)]
9pub enum ElfClass {
10    /// 32-bit
11    Elf32 = 1,
12    /// 64-bit
13    Elf64 = 2,
14}
15
16/// ELF data encoding
17#[derive(Debug, Clone, Copy, PartialEq, Eq)]
18pub enum ElfData {
19    /// Little-endian
20    LittleEndian = 1,
21    /// Big-endian
22    BigEndian = 2,
23}
24
25/// ELF file type
26#[derive(Debug, Clone, Copy, PartialEq, Eq)]
27pub enum ElfType {
28    /// Relocatable file
29    Rel = 1,
30    /// Executable file
31    Exec = 2,
32    /// Shared object file
33    Dyn = 3,
34}
35
36/// ELF machine architecture
37#[derive(Debug, Clone, Copy, PartialEq, Eq)]
38pub enum ElfMachine {
39    /// ARM
40    Arm = 40,
41    /// ARM64/AArch64
42    AArch64 = 183,
43}
44
45/// Section type
46#[derive(Debug, Clone, Copy, PartialEq, Eq)]
47pub enum SectionType {
48    /// Null section
49    Null = 0,
50    /// Program data
51    ProgBits = 1,
52    /// Symbol table
53    SymTab = 2,
54    /// String table
55    StrTab = 3,
56    /// Relocation entries with addends
57    Rela = 4,
58    /// Symbol hash table
59    Hash = 5,
60    /// Dynamic linking information
61    Dynamic = 6,
62    /// Note
63    Note = 7,
64    /// No space (BSS)
65    NoBits = 8,
66    /// Relocation entries
67    Rel = 9,
68}
69
70/// Section flags
71#[derive(Debug, Clone, Copy)]
72pub struct SectionFlags(pub u32);
73
74impl SectionFlags {
75    /// Writable
76    pub const WRITE: u32 = 0x1;
77    /// Occupies memory during execution
78    pub const ALLOC: u32 = 0x2;
79    /// Executable
80    pub const EXEC: u32 = 0x4;
81    /// Mergeable
82    pub const MERGE: u32 = 0x10;
83    /// Contains null-terminated strings
84    pub const STRINGS: u32 = 0x20;
85}
86
87/// ELF section
88#[derive(Debug, Clone)]
89pub struct Section {
90    /// Section name (index into string table)
91    pub name: String,
92    /// Section type
93    pub section_type: SectionType,
94    /// Section flags
95    pub flags: u32,
96    /// Virtual address
97    pub addr: u32,
98    /// Section data
99    pub data: Vec<u8>,
100    /// Alignment
101    pub align: u32,
102    /// Explicit size (for NoBits sections like .bss where data is empty)
103    pub explicit_size: Option<u32>,
104}
105
106impl Section {
107    /// Create a new section
108    pub fn new(name: &str, section_type: SectionType) -> Self {
109        Self {
110            name: name.to_string(),
111            section_type,
112            flags: 0,
113            addr: 0,
114            data: Vec::new(),
115            align: 1,
116            explicit_size: None,
117        }
118    }
119
120    /// Set flags
121    pub fn with_flags(mut self, flags: u32) -> Self {
122        self.flags = flags;
123        self
124    }
125
126    /// Set address
127    pub fn with_addr(mut self, addr: u32) -> Self {
128        self.addr = addr;
129        self
130    }
131
132    /// Set alignment
133    pub fn with_align(mut self, align: u32) -> Self {
134        self.align = align;
135        self
136    }
137
138    /// Add data
139    pub fn with_data(mut self, data: Vec<u8>) -> Self {
140        self.data = data;
141        self
142    }
143
144    /// Set explicit size (for NoBits sections like .bss where data is empty)
145    pub fn with_size(mut self, size: u32) -> Self {
146        self.explicit_size = Some(size);
147        self
148    }
149
150    /// Get the effective size of the section
151    pub fn size(&self) -> u32 {
152        self.explicit_size.unwrap_or(self.data.len() as u32)
153    }
154}
155
156/// Symbol binding
157#[derive(Debug, Clone, Copy, PartialEq, Eq)]
158pub enum SymbolBinding {
159    /// Local symbol
160    Local = 0,
161    /// Global symbol
162    Global = 1,
163    /// Weak symbol
164    Weak = 2,
165}
166
167/// Symbol type
168#[derive(Debug, Clone, Copy, PartialEq, Eq)]
169pub enum SymbolType {
170    /// No type
171    NoType = 0,
172    /// Object (data)
173    Object = 1,
174    /// Function
175    Func = 2,
176    /// Section
177    Section = 3,
178    /// File name
179    File = 4,
180}
181
182/// ELF symbol
183#[derive(Debug, Clone)]
184pub struct Symbol {
185    /// Symbol name
186    pub name: String,
187    /// Value/address
188    pub value: u32,
189    /// Size
190    pub size: u32,
191    /// Binding
192    pub binding: SymbolBinding,
193    /// Type
194    pub symbol_type: SymbolType,
195    /// Section index
196    pub section: u16,
197}
198
199impl Symbol {
200    /// Create a new symbol
201    pub fn new(name: &str) -> Self {
202        Self {
203            name: name.to_string(),
204            value: 0,
205            size: 0,
206            binding: SymbolBinding::Local,
207            symbol_type: SymbolType::NoType,
208            section: 0,
209        }
210    }
211
212    /// Set value
213    pub fn with_value(mut self, value: u32) -> Self {
214        self.value = value;
215        self
216    }
217
218    /// Set size
219    pub fn with_size(mut self, size: u32) -> Self {
220        self.size = size;
221        self
222    }
223
224    /// Set binding
225    pub fn with_binding(mut self, binding: SymbolBinding) -> Self {
226        self.binding = binding;
227        self
228    }
229
230    /// Set type
231    pub fn with_type(mut self, symbol_type: SymbolType) -> Self {
232        self.symbol_type = symbol_type;
233        self
234    }
235
236    /// Set section
237    pub fn with_section(mut self, section: u16) -> Self {
238        self.section = section;
239        self
240    }
241}
242
243/// Program header type
244#[derive(Debug, Clone, Copy, PartialEq, Eq)]
245pub enum ProgramType {
246    /// Null entry
247    Null = 0,
248    /// Loadable segment
249    Load = 1,
250    /// Dynamic linking info
251    Dynamic = 2,
252    /// Interpreter path
253    Interp = 3,
254    /// Note section
255    Note = 4,
256}
257
258/// Program header flags
259pub struct ProgramFlags;
260
261impl ProgramFlags {
262    /// Executable
263    pub const EXEC: u32 = 0x1;
264    /// Writable
265    pub const WRITE: u32 = 0x2;
266    /// Readable
267    pub const READ: u32 = 0x4;
268}
269
270/// ELF program header (segment)
271#[derive(Debug, Clone)]
272pub struct ProgramHeader {
273    /// Segment type
274    pub p_type: ProgramType,
275    /// Offset in file
276    pub offset: u32,
277    /// Virtual address
278    pub vaddr: u32,
279    /// Physical address
280    pub paddr: u32,
281    /// Size in file
282    pub filesz: u32,
283    /// Size in memory
284    pub memsz: u32,
285    /// Flags (R/W/X)
286    pub flags: u32,
287    /// Alignment
288    pub align: u32,
289}
290
291impl ProgramHeader {
292    /// Create a new LOAD segment
293    pub fn load(vaddr: u32, offset: u32, size: u32, flags: u32) -> Self {
294        Self {
295            p_type: ProgramType::Load,
296            offset,
297            vaddr,
298            paddr: vaddr, // Physical = virtual for simple cases
299            filesz: size,
300            memsz: size,
301            flags,
302            align: 4,
303        }
304    }
305
306    /// Create a new LOAD segment for BSS-like regions (no file data, only memory)
307    /// Used for .bss, linear memory, and other zero-initialized regions
308    pub fn load_nobits(vaddr: u32, memsz: u32, flags: u32) -> Self {
309        Self {
310            p_type: ProgramType::Load,
311            offset: 0, // No file offset for NoBits
312            vaddr,
313            paddr: vaddr, // Physical = virtual
314            filesz: 0,    // No file data
315            memsz,        // Memory size to allocate
316            flags,
317            align: 4,
318        }
319    }
320}
321
322/// ARM relocation type
323#[derive(Debug, Clone, Copy, PartialEq, Eq)]
324pub enum ArmRelocationType {
325    /// R_ARM_THM_CALL (10) — Thumb BL/BLX instruction (Cortex-M). This is the
326    /// correct relocation for a Thumb-2 `bl` call site; `Call`/R_ARM_CALL below
327    /// is the ARM-mode form and is mis-resolved by `ld` for Thumb calls.
328    ThmCall = 10,
329    /// R_ARM_CALL (28) — BL/BLX instruction
330    Call = 28,
331    /// R_ARM_JUMP24 (29) — B/BL<cond> instruction
332    Jump24 = 29,
333    /// R_ARM_ABS32 (2) — Direct 32-bit reference
334    Abs32 = 2,
335    /// R_ARM_MOVW_ABS_NC (43) — MOVW instruction (low 16 bits)
336    MovwAbsNc = 43,
337    /// R_ARM_MOVT_ABS (44) — MOVT instruction (high 16 bits)
338    MovtAbs = 44,
339}
340
341/// A built `.rel.<name>` section: its name offset in `.shstrtab`, the target
342/// section index it relocates (`sh_info`), its file offset, and the encoded
343/// REL entries. Internal to [`ElfBuilder::build`].
344struct ExtraRelSection {
345    name_offset: usize,
346    target_idx: u32,
347    offset: usize,
348    data: Vec<u8>,
349}
350
351/// ELF relocation entry (REL format, no addend)
352#[derive(Debug, Clone)]
353pub struct Relocation {
354    /// Offset within the section where the relocation applies
355    pub offset: u32,
356    /// Symbol index in the symbol table
357    pub symbol_index: u32,
358    /// Relocation type
359    pub reloc_type: ArmRelocationType,
360}
361
362/// ARM EABI version 5 (soft-float)
363pub const EF_ARM_EABI_VER5: u32 = 0x05000000;
364/// ARM hard-float ABI flag
365pub const EF_ARM_ABI_FLOAT_HARD: u32 = 0x00000400;
366/// ARM soft-float ABI flag
367pub const EF_ARM_ABI_FLOAT_SOFT: u32 = 0x00000200;
368
369/// ELF file builder
370pub struct ElfBuilder {
371    /// File class (32 or 64 bit)
372    class: ElfClass,
373    /// Data encoding
374    data: ElfData,
375    /// File type
376    elf_type: ElfType,
377    /// Machine architecture
378    machine: ElfMachine,
379    /// Entry point address
380    entry: u32,
381    /// ELF e_flags (EABI version + float ABI)
382    e_flags: u32,
383    /// Sections
384    sections: Vec<Section>,
385    /// Symbols
386    symbols: Vec<Symbol>,
387    /// Program headers (segments)
388    program_headers: Vec<ProgramHeader>,
389    /// Relocations for .text section
390    relocations: Vec<Relocation>,
391    /// Extra per-section relocation tables, keyed by the target section's name
392    /// (e.g. `.debug_line`). Each produces a `.rel.<name>` section. Kept separate
393    /// from `relocations` (the `.text` set) so the existing `.rel.text` byte
394    /// layout is untouched: when this is empty the build is byte-identical to the
395    /// pre-generalization output (VCR-DBG-001 PR C, #394).
396    extra_relocations: Vec<(String, Vec<Relocation>)>,
397}
398
399impl ElfBuilder {
400    /// Create a new ELF builder for ARM32
401    pub fn new_arm32() -> Self {
402        Self {
403            class: ElfClass::Elf32,
404            data: ElfData::LittleEndian,
405            elf_type: ElfType::Exec,
406            machine: ElfMachine::Arm,
407            entry: 0,
408            e_flags: EF_ARM_EABI_VER5,
409            sections: Vec::new(),
410            symbols: Vec::new(),
411            program_headers: Vec::new(),
412            relocations: Vec::new(),
413            extra_relocations: Vec::new(),
414        }
415    }
416
417    /// Set entry point
418    ///
419    /// For ARM (Thumb) targets, bit 0 is automatically set to indicate Thumb mode.
420    /// Cortex-M is Thumb-only, so function addresses in ELF must have bit 0 set.
421    pub fn with_entry(mut self, entry: u32) -> Self {
422        self.entry = if self.machine == ElfMachine::Arm {
423            entry | 1 // Set Thumb bit for ARM targets
424        } else {
425            entry
426        };
427        self
428    }
429
430    /// Set ELF e_flags (e.g. to add hard-float ABI)
431    pub fn set_flags(&mut self, flags: u32) {
432        self.e_flags = flags;
433    }
434
435    /// Set file type
436    pub fn with_type(mut self, elf_type: ElfType) -> Self {
437        self.elf_type = elf_type;
438        self
439    }
440
441    /// Add a section
442    pub fn add_section(&mut self, section: Section) {
443        self.sections.push(section);
444    }
445
446    /// Add a symbol
447    pub fn add_symbol(&mut self, symbol: Symbol) {
448        self.symbols.push(symbol);
449    }
450
451    /// Add a symbol and return its 1-based index in `.symtab` (index 0 is the
452    /// reserved null symbol). Use when a later relocation must reference this
453    /// symbol — e.g. the `.text` base symbol the DWARF `.rel.debug_*` records
454    /// resolve against (VCR-DBG-001).
455    pub fn add_symbol_indexed(&mut self, symbol: Symbol) -> u32 {
456        let index = self.symbols.len() as u32 + 1;
457        self.symbols.push(symbol);
458        index
459    }
460
461    /// Add a program header (segment)
462    pub fn add_program_header(&mut self, ph: ProgramHeader) {
463        self.program_headers.push(ph);
464    }
465
466    /// Add a relocation entry for the .text section
467    pub fn add_relocation(&mut self, reloc: Relocation) {
468        self.relocations.push(reloc);
469    }
470
471    /// Add a relocation table targeting a non-`.text` section by name (e.g.
472    /// `.debug_line`). Produces a separate `.rel.<name>` section whose `sh_info`
473    /// points at the named section. The section must already have been added via
474    /// [`add_section`]; if no matching section exists at build time the table is
475    /// silently dropped. Used by VCR-DBG-001 to relocate the DWARF `.text`
476    /// references so a host linker fixes them up alongside `.text`.
477    pub fn add_section_relocations(&mut self, target_section: &str, relocs: Vec<Relocation>) {
478        if relocs.is_empty() {
479            return;
480        }
481        self.extra_relocations
482            .push((target_section.to_string(), relocs));
483    }
484
485    /// Add an undefined external symbol (e.g., __meld_dispatch_import)
486    /// Returns the symbol index (1-based, accounting for null symbol)
487    pub fn add_undefined_symbol(&mut self, name: &str) -> u32 {
488        let index = self.symbols.len() as u32 + 1; // +1 for null symbol
489        self.symbols.push(Symbol {
490            name: name.to_string(),
491            value: 0,
492            size: 0,
493            binding: SymbolBinding::Global,
494            symbol_type: SymbolType::Func,
495            section: 0, // SHN_UNDEF
496        });
497        index
498    }
499
500    /// Build the ELF file to bytes
501    pub fn build(&self) -> Result<Vec<u8>> {
502        let mut output = Vec::new();
503
504        // ELF header size (52 bytes for ELF32)
505        let header_size = 52;
506        // Program header size (32 bytes for ELF32)
507        let ph_entry_size = 32;
508        let ph_count = self.program_headers.len();
509        let ph_table_size = ph_entry_size * ph_count;
510
511        // Reserve space for ELF header + program headers
512        output.resize(header_size + ph_table_size, 0);
513
514        // Build string table for section names
515        let (shstrtab_data, section_name_offsets, extra_rel_name_offsets) =
516            self.build_section_string_table();
517
518        // Build symbol string table
519        let (strtab_data, symbol_name_offsets) = self.build_symbol_string_table();
520
521        // Calculate section offsets (after ELF header + program headers)
522        let mut current_offset = header_size + ph_table_size;
523
524        // Section 1: .shstrtab (section name string table)
525        let shstrtab_offset = current_offset;
526        current_offset += shstrtab_data.len();
527
528        // Section 2: .strtab (symbol name string table)
529        let strtab_offset = current_offset;
530        current_offset += strtab_data.len();
531
532        // User sections
533        let mut section_offsets = Vec::new();
534        for section in &self.sections {
535            section_offsets.push(current_offset);
536            current_offset += section.data.len();
537        }
538
539        // Section 3: .symtab (symbol table)
540        let symtab_offset = current_offset;
541        let symtab_data = self.build_symbol_table(&symbol_name_offsets);
542        current_offset += symtab_data.len();
543
544        // Section 4+ (optional): .rel.text (relocations)
545        let rel_data = self.build_relocation_table();
546        let rel_offset = current_offset;
547        current_offset += rel_data.len();
548
549        // Extra per-section relocation tables (.rel.<name>), laid out after
550        // .rel.text. Each entry resolves its target section index by name; a
551        // table whose target section is absent is dropped. Empty when no
552        // --debug-line ⇒ byte-identical to the pre-generalization layout.
553        let mut extra_rel: Vec<ExtraRelSection> = Vec::new();
554        for (i, (target, relocs)) in self.extra_relocations.iter().enumerate() {
555            let Some(target_idx) = self.section_index_by_name(target) else {
556                continue;
557            };
558            let data = Self::encode_rel_entries(relocs);
559            let name_offset = extra_rel_name_offsets.get(i).copied().unwrap_or(0);
560            extra_rel.push(ExtraRelSection {
561                name_offset,
562                target_idx,
563                offset: current_offset,
564                data,
565            });
566            current_offset += extra_rel.last().unwrap().data.len();
567        }
568
569        // Section header table comes at the end
570        let sh_offset = current_offset;
571
572        // Now write all the data
573        output.extend_from_slice(&shstrtab_data);
574        output.extend_from_slice(&strtab_data);
575
576        for section in &self.sections {
577            output.extend_from_slice(&section.data);
578        }
579
580        output.extend_from_slice(&symtab_data);
581        output.extend_from_slice(&rel_data);
582        for er in &extra_rel {
583            output.extend_from_slice(&er.data);
584        }
585
586        // Write section headers
587        let section_headers = self.build_section_headers_with_rel(
588            &section_name_offsets,
589            shstrtab_offset,
590            &shstrtab_data,
591            strtab_offset,
592            &strtab_data,
593            symtab_offset,
594            &symtab_data,
595            &section_offsets,
596            rel_offset,
597            &rel_data,
598            &extra_rel,
599        );
600        output.extend_from_slice(&section_headers);
601
602        // Write program headers (right after ELF header)
603        // Auto-correct p_offset for LOAD segments by matching vaddr to section addrs
604        for (i, ph) in self.program_headers.iter().enumerate() {
605            let ph_offset = header_size + i * ph_entry_size;
606            let mut corrected_ph = ph.clone();
607            if corrected_ph.filesz > 0 {
608                // Find the section whose addr matches this segment's vaddr
609                for (si, section) in self.sections.iter().enumerate() {
610                    if section.addr == corrected_ph.vaddr && si < section_offsets.len() {
611                        corrected_ph.offset = section_offsets[si] as u32;
612                        break;
613                    }
614                }
615            }
616            self.write_program_header(
617                &mut output[ph_offset..ph_offset + ph_entry_size],
618                &corrected_ph,
619            );
620        }
621
622        // Now write the actual ELF header at the beginning
623        let has_rel = !self.relocations.is_empty();
624        let num_sections = 4 + self.sections.len() + if has_rel { 1 } else { 0 } + extra_rel.len();
625        let ph_offset = if ph_count > 0 { header_size as u32 } else { 0 };
626        self.write_elf_header_with_phdrs(
627            &mut output[0..header_size],
628            ph_offset,
629            ph_count as u16,
630            sh_offset as u32,
631            num_sections as u16,
632        )?;
633
634        Ok(output)
635    }
636
637    /// Write a single program header
638    fn write_program_header(&self, output: &mut [u8], ph: &ProgramHeader) {
639        let mut cursor = 0;
640
641        // p_type (4 bytes)
642        output[cursor..cursor + 4].copy_from_slice(&(ph.p_type as u32).to_le_bytes());
643        cursor += 4;
644
645        // p_offset (4 bytes)
646        output[cursor..cursor + 4].copy_from_slice(&ph.offset.to_le_bytes());
647        cursor += 4;
648
649        // p_vaddr (4 bytes)
650        output[cursor..cursor + 4].copy_from_slice(&ph.vaddr.to_le_bytes());
651        cursor += 4;
652
653        // p_paddr (4 bytes)
654        output[cursor..cursor + 4].copy_from_slice(&ph.paddr.to_le_bytes());
655        cursor += 4;
656
657        // p_filesz (4 bytes)
658        output[cursor..cursor + 4].copy_from_slice(&ph.filesz.to_le_bytes());
659        cursor += 4;
660
661        // p_memsz (4 bytes)
662        output[cursor..cursor + 4].copy_from_slice(&ph.memsz.to_le_bytes());
663        cursor += 4;
664
665        // p_flags (4 bytes)
666        output[cursor..cursor + 4].copy_from_slice(&ph.flags.to_le_bytes());
667        cursor += 4;
668
669        // p_align (4 bytes)
670        output[cursor..cursor + 4].copy_from_slice(&ph.align.to_le_bytes());
671    }
672
673    /// Write ELF header with program header info
674    fn write_elf_header_with_phdrs(
675        &self,
676        output: &mut [u8],
677        ph_offset: u32,
678        ph_count: u16,
679        sh_offset: u32,
680        sh_count: u16,
681    ) -> Result<()> {
682        let mut cursor = 0;
683
684        // ELF magic number
685        output[cursor..cursor + 4].copy_from_slice(&[0x7f, b'E', b'L', b'F']);
686        cursor += 4;
687
688        // Class (32-bit)
689        output[cursor] = self.class as u8;
690        cursor += 1;
691
692        // Data (little-endian)
693        output[cursor] = self.data as u8;
694        cursor += 1;
695
696        // Version
697        output[cursor] = 1;
698        cursor += 1;
699
700        // OS/ABI
701        output[cursor] = 0; // System V
702        cursor += 1;
703
704        // ABI version
705        output[cursor] = 0;
706        cursor += 1;
707
708        // Padding (7 bytes)
709        output[cursor..cursor + 7].copy_from_slice(&[0; 7]);
710        cursor += 7;
711
712        // Type (little-endian u16)
713        let etype = self.elf_type as u16;
714        output[cursor..cursor + 2].copy_from_slice(&etype.to_le_bytes());
715        cursor += 2;
716
717        // Machine (little-endian u16)
718        let machine = self.machine as u16;
719        output[cursor..cursor + 2].copy_from_slice(&machine.to_le_bytes());
720        cursor += 2;
721
722        // Version (little-endian u32)
723        output[cursor..cursor + 4].copy_from_slice(&1u32.to_le_bytes());
724        cursor += 4;
725
726        // Entry point (little-endian u32)
727        output[cursor..cursor + 4].copy_from_slice(&self.entry.to_le_bytes());
728        cursor += 4;
729
730        // Program header offset (little-endian u32)
731        output[cursor..cursor + 4].copy_from_slice(&ph_offset.to_le_bytes());
732        cursor += 4;
733
734        // Section header offset (little-endian u32)
735        output[cursor..cursor + 4].copy_from_slice(&sh_offset.to_le_bytes());
736        cursor += 4;
737
738        // Flags (little-endian u32) - ARM EABI version 5 + float ABI
739        output[cursor..cursor + 4].copy_from_slice(&self.e_flags.to_le_bytes());
740        cursor += 4;
741
742        // ELF header size (little-endian u16)
743        output[cursor..cursor + 2].copy_from_slice(&52u16.to_le_bytes());
744        cursor += 2;
745
746        // Program header entry size (little-endian u16)
747        let ph_entry_size: u16 = if ph_count > 0 { 32 } else { 0 };
748        output[cursor..cursor + 2].copy_from_slice(&ph_entry_size.to_le_bytes());
749        cursor += 2;
750
751        // Program header count (little-endian u16)
752        output[cursor..cursor + 2].copy_from_slice(&ph_count.to_le_bytes());
753        cursor += 2;
754
755        // Section header entry size (little-endian u16)
756        output[cursor..cursor + 2].copy_from_slice(&40u16.to_le_bytes());
757        cursor += 2;
758
759        // Section header count (little-endian u16)
760        output[cursor..cursor + 2].copy_from_slice(&sh_count.to_le_bytes());
761        cursor += 2;
762
763        // Section header string table index (little-endian u16) - .shstrtab is section 1
764        output[cursor..cursor + 2].copy_from_slice(&1u16.to_le_bytes());
765
766        Ok(())
767    }
768
769    /// Build section name string table. Returns the bytes, the per-user-section
770    /// name offsets, and the per-extra-relocation `.rel.<name>` name offsets
771    /// (parallel to `self.extra_relocations`). The extra-rel names are appended
772    /// AFTER `.rel.text`, so when `extra_relocations` is empty the table is
773    /// byte-identical to the pre-generalization layout.
774    fn build_section_string_table(&self) -> (Vec<u8>, Vec<usize>, Vec<usize>) {
775        let mut strtab = vec![0]; // null string at offset 0
776        let mut offsets = Vec::new();
777
778        // Standard sections
779        strtab.extend_from_slice(b".shstrtab\0");
780        strtab.extend_from_slice(b".strtab\0");
781        strtab.extend_from_slice(b".symtab\0");
782
783        // User sections
784        for section in &self.sections {
785            let offset = strtab.len();
786            offsets.push(offset);
787            strtab.extend_from_slice(section.name.as_bytes());
788            strtab.push(0);
789        }
790
791        // .rel.text (if relocations exist)
792        if !self.relocations.is_empty() {
793            strtab.extend_from_slice(b".rel.text\0");
794        }
795
796        // .rel.<name> for each extra per-section relocation table.
797        let mut extra_rel_offsets = Vec::new();
798        for (target, _) in &self.extra_relocations {
799            let offset = strtab.len();
800            extra_rel_offsets.push(offset);
801            strtab.extend_from_slice(format!(".rel{target}\0").as_bytes());
802        }
803
804        (strtab, offsets, extra_rel_offsets)
805    }
806
807    /// Build symbol name string table
808    fn build_symbol_string_table(&self) -> (Vec<u8>, Vec<usize>) {
809        let mut strtab = vec![0]; // null string at offset 0
810        let mut offsets = Vec::new();
811
812        for symbol in &self.symbols {
813            let offset = strtab.len();
814            offsets.push(offset);
815            strtab.extend_from_slice(symbol.name.as_bytes());
816            strtab.push(0);
817        }
818
819        (strtab, offsets)
820    }
821
822    /// Build relocation table (ELF32 REL entries: 8 bytes each)
823    fn build_relocation_table(&self) -> Vec<u8> {
824        Self::encode_rel_entries(&self.relocations)
825    }
826
827    /// Encode a slice of relocations as ELF32 REL entries (8 bytes each). Shared
828    /// by `.rel.text` and the per-section `.rel.<name>` tables.
829    fn encode_rel_entries(relocs: &[Relocation]) -> Vec<u8> {
830        let mut rel_data = Vec::new();
831        for reloc in relocs {
832            // r_offset (4 bytes)
833            rel_data.extend_from_slice(&reloc.offset.to_le_bytes());
834            // r_info (4 bytes) = (sym_index << 8) | type
835            let r_info = (reloc.symbol_index << 8) | (reloc.reloc_type as u32);
836            rel_data.extend_from_slice(&r_info.to_le_bytes());
837        }
838        rel_data
839    }
840
841    /// Resolve a target section name to its ELF section index. User sections
842    /// begin at index 4 (null=0, shstrtab=1, strtab=2, symtab=3). Returns `None`
843    /// if no user section has that name.
844    fn section_index_by_name(&self, name: &str) -> Option<u32> {
845        self.sections
846            .iter()
847            .position(|s| s.name == name)
848            .map(|pos| 4 + pos as u32)
849    }
850
851    /// Build symbol table
852    fn build_symbol_table(&self, name_offsets: &[usize]) -> Vec<u8> {
853        let mut symtab = Vec::new();
854
855        // First entry is always null symbol
856        symtab.extend_from_slice(&[0u8; 16]); // 16 bytes per symbol in ELF32
857
858        // User symbols
859        for (i, symbol) in self.symbols.iter().enumerate() {
860            let name_offset = if i < name_offsets.len() {
861                name_offsets[i] as u32
862            } else {
863                0
864            };
865
866            // st_name (4 bytes)
867            symtab.extend_from_slice(&name_offset.to_le_bytes());
868
869            // st_value (4 bytes)
870            // For ARM targets, STT_FUNC symbols must have bit 0 set (Thumb interworking)
871            let value = if self.machine == ElfMachine::Arm && symbol.symbol_type == SymbolType::Func
872            {
873                symbol.value | 1
874            } else {
875                symbol.value
876            };
877            symtab.extend_from_slice(&value.to_le_bytes());
878
879            // st_size (4 bytes)
880            symtab.extend_from_slice(&symbol.size.to_le_bytes());
881
882            // st_info (1 byte) = (binding << 4) | (type & 0xf)
883            let info = ((symbol.binding as u8) << 4) | (symbol.symbol_type as u8 & 0xf);
884            symtab.push(info);
885
886            // st_other (1 byte)
887            symtab.push(0);
888
889            // st_shndx (2 bytes)
890            symtab.extend_from_slice(&symbol.section.to_le_bytes());
891        }
892
893        symtab
894    }
895
896    /// Build section headers (with optional .rel.text)
897    #[allow(clippy::too_many_arguments)]
898    fn build_section_headers_with_rel(
899        &self,
900        section_name_offsets: &[usize],
901        shstrtab_offset: usize,
902        shstrtab_data: &[u8],
903        strtab_offset: usize,
904        strtab_data: &[u8],
905        symtab_offset: usize,
906        symtab_data: &[u8],
907        section_offsets: &[usize],
908        rel_offset: usize,
909        rel_data: &[u8],
910        extra_rel: &[ExtraRelSection],
911    ) -> Vec<u8> {
912        let mut headers = Vec::new();
913
914        // Section header size is 40 bytes for ELF32
915
916        // Section 0: null section
917        headers.extend_from_slice(&[0u8; 40]);
918
919        // Section 1: .shstrtab
920        self.write_section_header(
921            &mut headers,
922            1,
923            SectionType::StrTab as u32,
924            0,
925            0,
926            shstrtab_offset as u32,
927            shstrtab_data.len() as u32,
928            0,
929            0,
930            1,
931            0,
932        );
933
934        // Section 2: .strtab
935        let strtab_name_offset = ".shstrtab\0".len();
936        self.write_section_header(
937            &mut headers,
938            strtab_name_offset as u32,
939            SectionType::StrTab as u32,
940            0,
941            0,
942            strtab_offset as u32,
943            strtab_data.len() as u32,
944            0,
945            0,
946            1,
947            0,
948        );
949
950        // Section 3: .symtab (links to .strtab which is section 2)
951        let symtab_name_offset = ".shstrtab\0.strtab\0".len();
952        self.write_section_header(
953            &mut headers,
954            symtab_name_offset as u32,
955            SectionType::SymTab as u32,
956            0,
957            0,
958            symtab_offset as u32,
959            symtab_data.len() as u32,
960            2,
961            1,
962            4,
963            16,
964        );
965
966        // User sections
967        for (i, section) in self.sections.iter().enumerate() {
968            let name_offset = if i < section_name_offsets.len() {
969                section_name_offsets[i] as u32
970            } else {
971                0
972            };
973            let offset = if i < section_offsets.len() {
974                section_offsets[i] as u32
975            } else {
976                0
977            };
978
979            self.write_section_header(
980                &mut headers,
981                name_offset,
982                section.section_type as u32,
983                section.flags,
984                section.addr,
985                offset,
986                section.size(),
987                0,
988                0,
989                section.align,
990                0,
991            );
992        }
993
994        // .rel.text section (if relocations exist)
995        if !rel_data.is_empty() {
996            let rel_name_offset = self.rel_text_shstrtab_offset();
997            // sh_link = symtab section index (3), sh_info = .text section index (4, first user section)
998            let text_section_idx = 4u32; // null(0) + shstrtab(1) + strtab(2) + symtab(3) + .text(4)
999            self.write_section_header(
1000                &mut headers,
1001                rel_name_offset as u32,
1002                SectionType::Rel as u32,
1003                0,
1004                0,
1005                rel_offset as u32,
1006                rel_data.len() as u32,
1007                3,                // sh_link = .symtab section index
1008                text_section_idx, // sh_info = section to which relocations apply
1009                4,
1010                8, // Each REL entry is 8 bytes
1011            );
1012        }
1013
1014        // Extra .rel.<name> sections (e.g. .rel.debug_line). Same shape as
1015        // .rel.text but sh_info points at the named target section.
1016        for er in extra_rel {
1017            self.write_section_header(
1018                &mut headers,
1019                er.name_offset as u32,
1020                SectionType::Rel as u32,
1021                0,
1022                0,
1023                er.offset as u32,
1024                er.data.len() as u32,
1025                3,             // sh_link = .symtab section index
1026                er.target_idx, // sh_info = relocated section
1027                4,
1028                8, // Each REL entry is 8 bytes
1029            );
1030        }
1031
1032        headers
1033    }
1034
1035    /// Compute the shstrtab offset where .rel.text name begins
1036    fn rel_text_shstrtab_offset(&self) -> usize {
1037        // Layout: \0 .shstrtab\0 .strtab\0 .symtab\0 [user sections...] .rel.text\0
1038        let mut offset = 1 + ".shstrtab\0".len() + ".strtab\0".len() + ".symtab\0".len();
1039        for section in &self.sections {
1040            offset += section.name.len() + 1;
1041        }
1042        offset
1043    }
1044
1045    /// Write a single section header
1046    #[allow(clippy::too_many_arguments)]
1047    fn write_section_header(
1048        &self,
1049        output: &mut Vec<u8>,
1050        name: u32,
1051        sh_type: u32,
1052        flags: u32,
1053        addr: u32,
1054        offset: u32,
1055        size: u32,
1056        link: u32,
1057        info: u32,
1058        align: u32,
1059        entsize: u32,
1060    ) {
1061        output.extend_from_slice(&name.to_le_bytes());
1062        output.extend_from_slice(&sh_type.to_le_bytes());
1063        output.extend_from_slice(&flags.to_le_bytes());
1064        output.extend_from_slice(&addr.to_le_bytes());
1065        output.extend_from_slice(&offset.to_le_bytes());
1066        output.extend_from_slice(&size.to_le_bytes());
1067        output.extend_from_slice(&link.to_le_bytes());
1068        output.extend_from_slice(&info.to_le_bytes());
1069        output.extend_from_slice(&align.to_le_bytes());
1070        output.extend_from_slice(&entsize.to_le_bytes());
1071    }
1072
1073    /// Write ELF header (legacy method for tests)
1074    #[allow(dead_code)]
1075    fn write_elf_header(&self, output: &mut Vec<u8>) -> Result<()> {
1076        // ELF magic number
1077        output.extend_from_slice(&[0x7f, b'E', b'L', b'F']);
1078
1079        // Class (32-bit)
1080        output.push(self.class as u8);
1081
1082        // Data (little-endian)
1083        output.push(self.data as u8);
1084
1085        // Version
1086        output.push(1);
1087
1088        // OS/ABI
1089        output.push(0); // System V
1090
1091        // ABI version
1092        output.push(0);
1093
1094        // Padding
1095        output.extend_from_slice(&[0; 7]);
1096
1097        // Type (little-endian u16)
1098        let etype = self.elf_type as u16;
1099        output.extend_from_slice(&etype.to_le_bytes());
1100
1101        // Machine (little-endian u16)
1102        let machine = self.machine as u16;
1103        output.extend_from_slice(&machine.to_le_bytes());
1104
1105        // Version (little-endian u32)
1106        output.extend_from_slice(&1u32.to_le_bytes());
1107
1108        // Entry point (little-endian u32)
1109        output.extend_from_slice(&self.entry.to_le_bytes());
1110
1111        // Program header offset (little-endian u32)
1112        output.extend_from_slice(&0u32.to_le_bytes());
1113
1114        // Section header offset (little-endian u32)
1115        output.extend_from_slice(&0u32.to_le_bytes());
1116
1117        // Flags (little-endian u32)
1118        output.extend_from_slice(&0u32.to_le_bytes());
1119
1120        // ELF header size (little-endian u16)
1121        output.extend_from_slice(&52u16.to_le_bytes());
1122
1123        // Program header entry size (little-endian u16)
1124        output.extend_from_slice(&0u16.to_le_bytes());
1125
1126        // Program header count (little-endian u16)
1127        output.extend_from_slice(&0u16.to_le_bytes());
1128
1129        // Section header entry size (little-endian u16)
1130        output.extend_from_slice(&40u16.to_le_bytes());
1131
1132        // Section header count (little-endian u16)
1133        output.extend_from_slice(&0u16.to_le_bytes());
1134
1135        // Section header string table index (little-endian u16)
1136        output.extend_from_slice(&0u16.to_le_bytes());
1137
1138        Ok(())
1139    }
1140}
1141
1142#[cfg(test)]
1143mod tests {
1144    use super::*;
1145
1146    #[test]
1147    fn test_elf_builder_creation() {
1148        let builder = ElfBuilder::new_arm32();
1149        assert_eq!(builder.class, ElfClass::Elf32);
1150        assert_eq!(builder.data, ElfData::LittleEndian);
1151        assert_eq!(builder.machine, ElfMachine::Arm);
1152    }
1153
1154    #[test]
1155    fn test_section_creation() {
1156        let section = Section::new(".text", SectionType::ProgBits)
1157            .with_flags(SectionFlags::ALLOC | SectionFlags::EXEC)
1158            .with_addr(0x8000)
1159            .with_align(4);
1160
1161        assert_eq!(section.name, ".text");
1162        assert_eq!(section.section_type, SectionType::ProgBits);
1163        assert_eq!(section.addr, 0x8000);
1164        assert_eq!(section.align, 4);
1165    }
1166
1167    #[test]
1168    fn test_symbol_creation() {
1169        let symbol = Symbol::new("main")
1170            .with_value(0x8000)
1171            .with_size(128)
1172            .with_binding(SymbolBinding::Global)
1173            .with_type(SymbolType::Func)
1174            .with_section(1);
1175
1176        assert_eq!(symbol.name, "main");
1177        assert_eq!(symbol.value, 0x8000);
1178        assert_eq!(symbol.size, 128);
1179        assert_eq!(symbol.binding, SymbolBinding::Global);
1180        assert_eq!(symbol.symbol_type, SymbolType::Func);
1181    }
1182
1183    #[test]
1184    fn test_elf_header_generation() {
1185        let builder = ElfBuilder::new_arm32().with_entry(0x8000);
1186        let elf = builder.build().unwrap();
1187
1188        // Check magic number
1189        assert_eq!(&elf[0..4], &[0x7f, b'E', b'L', b'F']);
1190
1191        // Check class (32-bit)
1192        assert_eq!(elf[4], 1);
1193
1194        // Check data (little-endian)
1195        assert_eq!(elf[5], 1);
1196
1197        // Check version
1198        assert_eq!(elf[6], 1);
1199    }
1200
1201    #[test]
1202    fn test_add_sections() {
1203        let mut builder = ElfBuilder::new_arm32();
1204
1205        let text = Section::new(".text", SectionType::ProgBits)
1206            .with_flags(SectionFlags::ALLOC | SectionFlags::EXEC);
1207
1208        let data = Section::new(".data", SectionType::ProgBits)
1209            .with_flags(SectionFlags::ALLOC | SectionFlags::WRITE);
1210
1211        builder.add_section(text);
1212        builder.add_section(data);
1213
1214        assert_eq!(builder.sections.len(), 2);
1215    }
1216
1217    #[test]
1218    fn test_add_symbols() {
1219        let mut builder = ElfBuilder::new_arm32();
1220
1221        let main_sym = Symbol::new("main")
1222            .with_binding(SymbolBinding::Global)
1223            .with_type(SymbolType::Func);
1224
1225        let data_sym = Symbol::new("data")
1226            .with_binding(SymbolBinding::Local)
1227            .with_type(SymbolType::Object);
1228
1229        builder.add_symbol(main_sym);
1230        builder.add_symbol(data_sym);
1231
1232        assert_eq!(builder.symbols.len(), 2);
1233    }
1234
1235    #[test]
1236    fn test_complete_elf_generation() {
1237        // Create a complete ELF file with sections and symbols
1238        let mut builder = ElfBuilder::new_arm32()
1239            .with_entry(0x8000)
1240            .with_type(ElfType::Exec);
1241
1242        // Add .text section with some ARM code
1243        let text_code = vec![
1244            0x00, 0x48, 0x2d, 0xe9, // push {fp, lr}
1245            0x04, 0xb0, 0x8d, 0xe2, // add fp, sp, #4
1246            0x00, 0x00, 0xa0, 0xe3, // mov r0, #0
1247            0x00, 0x88, 0xbd, 0xe8, // pop {fp, pc}
1248        ];
1249        let text = Section::new(".text", SectionType::ProgBits)
1250            .with_flags(SectionFlags::ALLOC | SectionFlags::EXEC)
1251            .with_addr(0x8000)
1252            .with_align(4)
1253            .with_data(text_code);
1254
1255        builder.add_section(text);
1256
1257        // Add .data section
1258        let data_content = vec![0x01, 0x02, 0x03, 0x04];
1259        let data = Section::new(".data", SectionType::ProgBits)
1260            .with_flags(SectionFlags::ALLOC | SectionFlags::WRITE)
1261            .with_addr(0x8100)
1262            .with_align(4)
1263            .with_data(data_content);
1264
1265        builder.add_section(data);
1266
1267        // Add .bss section (no data)
1268        let bss = Section::new(".bss", SectionType::NoBits)
1269            .with_flags(SectionFlags::ALLOC | SectionFlags::WRITE)
1270            .with_addr(0x8200)
1271            .with_align(4);
1272
1273        builder.add_section(bss);
1274
1275        // Add symbols
1276        let main_sym = Symbol::new("main")
1277            .with_value(0x8000)
1278            .with_size(16)
1279            .with_binding(SymbolBinding::Global)
1280            .with_type(SymbolType::Func)
1281            .with_section(4); // .text is section 4 (0=null, 1=shstrtab, 2=strtab, 3=symtab, 4=.text)
1282
1283        builder.add_symbol(main_sym);
1284
1285        let data_var = Symbol::new("global_var")
1286            .with_value(0x8100)
1287            .with_size(4)
1288            .with_binding(SymbolBinding::Global)
1289            .with_type(SymbolType::Object)
1290            .with_section(5); // .data is section 5
1291
1292        builder.add_symbol(data_var);
1293
1294        // Build the ELF file
1295        let elf = builder.build().unwrap();
1296
1297        // Validate ELF header
1298        assert_eq!(&elf[0..4], &[0x7f, b'E', b'L', b'F']);
1299        assert_eq!(elf[4], 1); // 32-bit
1300        assert_eq!(elf[5], 1); // little-endian
1301        assert_eq!(elf[6], 1); // version
1302
1303        // Check that we have a reasonable file size
1304        assert!(elf.len() > 52); // At least header size
1305        assert!(elf.len() < 10000); // Reasonable upper bound
1306
1307        // Validate entry point is set correctly (Thumb bit set for ARM)
1308        let entry_bytes = &elf[24..28];
1309        let entry = u32::from_le_bytes([
1310            entry_bytes[0],
1311            entry_bytes[1],
1312            entry_bytes[2],
1313            entry_bytes[3],
1314        ]);
1315        assert_eq!(entry, 0x8001); // 0x8000 | 1 (Thumb bit)
1316
1317        // Validate section header offset is non-zero
1318        let sh_off_bytes = &elf[32..36];
1319        let sh_off = u32::from_le_bytes([
1320            sh_off_bytes[0],
1321            sh_off_bytes[1],
1322            sh_off_bytes[2],
1323            sh_off_bytes[3],
1324        ]);
1325        assert!(sh_off > 0);
1326
1327        // Validate section count (null + shstrtab + strtab + symtab + .text + .data + .bss = 7)
1328        let sh_num_bytes = &elf[48..50];
1329        let sh_num = u16::from_le_bytes([sh_num_bytes[0], sh_num_bytes[1]]);
1330        assert_eq!(sh_num, 7);
1331
1332        // Validate string table index points to .shstrtab (section 1)
1333        let shstrndx_bytes = &elf[50..52];
1334        let shstrndx = u16::from_le_bytes([shstrndx_bytes[0], shstrndx_bytes[1]]);
1335        assert_eq!(shstrndx, 1);
1336    }
1337
1338    #[test]
1339    fn test_string_table_generation() {
1340        let mut builder = ElfBuilder::new_arm32();
1341
1342        builder.add_section(Section::new(".text", SectionType::ProgBits));
1343        builder.add_section(Section::new(".data", SectionType::ProgBits));
1344
1345        let (strtab, offsets, _extra_rel_offsets) = builder.build_section_string_table();
1346
1347        // Should have null byte at start
1348        assert_eq!(strtab[0], 0);
1349
1350        // Should contain .shstrtab, .strtab, .symtab, .text, .data
1351        let strtab_str = String::from_utf8_lossy(&strtab);
1352        assert!(strtab_str.contains(".shstrtab"));
1353        assert!(strtab_str.contains(".strtab"));
1354        assert!(strtab_str.contains(".symtab"));
1355        assert!(strtab_str.contains(".text"));
1356        assert!(strtab_str.contains(".data"));
1357
1358        // Should have offsets for user sections
1359        assert_eq!(offsets.len(), 2);
1360    }
1361
1362    #[test]
1363    fn test_relocation_support() {
1364        let mut builder = ElfBuilder::new_arm32()
1365            .with_entry(0x8000)
1366            .with_type(ElfType::Rel);
1367
1368        // Add .text section with a BL placeholder
1369        let text_code = vec![0x00u8; 16]; // 4 instructions of placeholder
1370        let text = Section::new(".text", SectionType::ProgBits)
1371            .with_flags(SectionFlags::ALLOC | SectionFlags::EXEC)
1372            .with_addr(0x8000)
1373            .with_align(4)
1374            .with_data(text_code);
1375        builder.add_section(text);
1376
1377        // Add undefined external symbol
1378        let sym_idx = builder.add_undefined_symbol("__meld_dispatch_import");
1379        assert!(sym_idx > 0);
1380
1381        // Add relocation for the BL at offset 4
1382        builder.add_relocation(Relocation {
1383            offset: 4,
1384            symbol_index: sym_idx,
1385            reloc_type: ArmRelocationType::Call,
1386        });
1387
1388        let elf = builder.build().unwrap();
1389
1390        // Verify ELF is valid
1391        assert_eq!(&elf[0..4], &[0x7f, b'E', b'L', b'F']);
1392
1393        // Section count should include .rel.text
1394        // null(1) + shstrtab(1) + strtab(1) + symtab(1) + .text(1) + .rel.text(1) = 6
1395        let sh_num = u16::from_le_bytes([elf[48], elf[49]]);
1396        assert_eq!(sh_num, 6);
1397
1398        // Verify the symbol table contains the undefined symbol
1399        // (section = 0 for SHN_UNDEF)
1400        let has_undef = elf
1401            .windows(b"__meld_dispatch_import".len())
1402            .any(|w| w == b"__meld_dispatch_import");
1403        assert!(
1404            has_undef,
1405            "ELF should contain __meld_dispatch_import symbol name"
1406        );
1407    }
1408
1409    #[test]
1410    fn test_symbol_table_encoding() {
1411        let mut builder = ElfBuilder::new_arm32();
1412
1413        let sym = Symbol::new("test_func")
1414            .with_value(0x1000)
1415            .with_size(64)
1416            .with_binding(SymbolBinding::Global)
1417            .with_type(SymbolType::Func)
1418            .with_section(1);
1419
1420        builder.add_symbol(sym);
1421
1422        let (_strtab, offsets) = builder.build_symbol_string_table();
1423        let symtab = builder.build_symbol_table(&offsets);
1424
1425        // Should have null symbol (16 bytes) + 1 symbol (16 bytes) = 32 bytes
1426        assert_eq!(symtab.len(), 32);
1427
1428        // First symbol should be all zeros
1429        assert!(symtab[0..16].iter().all(|&b| b == 0));
1430
1431        // Second symbol should have correct encoding
1432        // Check st_value (bytes 4-7 of second entry)
1433        // For ARM STT_FUNC symbols, bit 0 is set for Thumb interworking
1434        let value_bytes = &symtab[20..24];
1435        let value = u32::from_le_bytes([
1436            value_bytes[0],
1437            value_bytes[1],
1438            value_bytes[2],
1439            value_bytes[3],
1440        ]);
1441        assert_eq!(value, 0x1001); // 0x1000 | 1 (Thumb bit)
1442
1443        // Check st_size (bytes 8-11 of second entry)
1444        let size_bytes = &symtab[24..28];
1445        let size = u32::from_le_bytes([size_bytes[0], size_bytes[1], size_bytes[2], size_bytes[3]]);
1446        assert_eq!(size, 64);
1447
1448        // Check st_info (byte 12 of second entry)
1449        let info = symtab[28];
1450        let binding = info >> 4;
1451        let sym_type = info & 0xf;
1452        assert_eq!(binding, SymbolBinding::Global as u8);
1453        assert_eq!(sym_type, SymbolType::Func as u8);
1454    }
1455}
synth_backend/elf_builder.rs

synth_backend/
elf_builder.rs
