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Support compound statements

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This commit is contained in:
Eugen Wissner
2024-03-11 10:43:26 +01:00
parent 2c396ece17
commit 25657ac36d
12 changed files with 242 additions and 86 deletions
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47
backend/target.cpp
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@ -32,8 +32,6 @@ namespace elna::riscv
// Create string table writer
ELFIO::string_section_accessor stra(str_sec);
// Add label name
ELFIO::Elf32_Word str_index = stra.add_string("msg");
// Create read only data section
ELFIO::section* ro_sec = writer.sections.add(".rodata");
@ -50,15 +48,6 @@ namespace elna::riscv
sym_sec->set_entry_size(writer.get_default_entry_size(ELFIO::SHT_SYMTAB));
sym_sec->set_link(str_sec->get_index());
// Create symbol table writer
ELFIO::symbol_section_accessor syma(writer, sym_sec);
auto label_sym = syma.add_symbol(stra, ".CL0", 0x00000000, strlen("%d\n") + 1,
ELFIO::STB_LOCAL, ELFIO::STT_NOTYPE, 0, ro_sec->get_index());
syma.add_symbol(stra, "main", 0x00000000, instructions_size,
ELFIO::STB_GLOBAL, ELFIO::STT_FUNC, 0, text_sec->get_index());
auto printf_sym = syma.add_symbol(stra, "printf", 0x00000000, 0,
ELFIO::STB_GLOBAL, ELFIO::STT_NOTYPE, 0, ELFIO::SHN_UNDEF);
// Create relocation table section
ELFIO::section* rel_sec = writer.sections.add(".rel.text");
rel_sec->set_type(ELFIO::SHT_REL);
@ -68,15 +57,35 @@ namespace elna::riscv
rel_sec->set_link(sym_sec->get_index());
rel_sec->set_flags(ELFIO::SHF_ALLOC);
// Create relocation table writer
// Create symbol relocation table writers
ELFIO::symbol_section_accessor syma(writer, sym_sec);
ELFIO::relocation_section_accessor rela(writer, rel_sec);
// Add relocation entry (adjust address at offset 11)
rela.add_entry(_visitor->references[0].offset, label_sym, 26 /* ELFIO::R_RISCV_HI20 */);
rela.add_entry(_visitor->references[0].offset, label_sym, 51 /* ELFIO::R_RISCV_RELAX */);
rela.add_entry(_visitor->references[1].offset, label_sym, 27 /* ELFIO::R_RISCV_LO12_I */);
rela.add_entry(_visitor->references[1].offset, label_sym, 51 /* ELFIO::R_RISCV_RELAX */);
rela.add_entry(_visitor->references[2].offset, printf_sym, 18 /* ELFIO::R_RISCV_CALL */);
rela.add_entry(_visitor->references[2].offset, printf_sym, 51 /* ELFIO::R_RISCV_RELAX */);
ELFIO::Elf_Word digit_symbol = syma.add_symbol(stra, ".CL0", 0x00000000, strlen("%d\n") + 1,
ELFIO::STB_LOCAL, ELFIO::STT_NOTYPE, 0, ro_sec->get_index());
ELFIO::Elf_Word printf_symbol = syma.add_symbol(stra, "printf", 0x00000000, 0,
ELFIO::STB_GLOBAL, ELFIO::STT_NOTYPE, 0, ELFIO::SHN_UNDEF);
for (auto& reference : _visitor->references)
{
// The loop assumes that address_t::lower12i always follows address_t::high20.
switch (reference.target)
{
case address_t::high20:
rela.add_entry(reference.offset, digit_symbol, 26 /* ELFIO::R_RISCV_HI20 */);
rela.add_entry(reference.offset, digit_symbol, 51 /* ELFIO::R_RISCV_RELAX */);
break;
case address_t::lower12i:
rela.add_entry(reference.offset, digit_symbol, 27 /* ELFIO::R_RISCV_LO12_I */);
rela.add_entry(reference.offset, digit_symbol, 51 /* ELFIO::R_RISCV_RELAX */);
break;
case address_t::text:
rela.add_entry(reference.offset, printf_symbol, 18 /* ELFIO::R_RISCV_CALL */);
rela.add_entry(reference.offset, printf_symbol, 51 /* ELFIO::R_RISCV_RELAX */);
break;
}
}
syma.add_symbol(stra, "main", 0x00000000, instructions_size,
ELFIO::STB_GLOBAL, ELFIO::STT_FUNC, 0, text_sec->get_index());
// Create ELF object file
writer.save(out_file);