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David Gonzalez Martin 2024-09-19 06:53:18 -06:00 committed by David
parent 9d310e36e4
commit 271c2614cc
1 changed files with 93 additions and 10 deletions
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103
bootstrap/main.c
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@ -650,6 +650,29 @@ typedef enum DwarfTag : u16
DW_TAG_hi_user = 0xffff,
} DwarfTag;
typedef enum DwarfOpcode : u8
{
DW_LNS_copy = 1,
DW_LNS_advance_pc = 2,
DW_LNS_advance_line = 3,
DW_LNS_set_file = 4,
DW_LNS_set_column = 5,
DW_LNS_negate_stmt = 6,
DW_LNS_set_basic_block = 7,
DW_LNS_const_add_pc = 8,
DW_LNS_fixed_advance_pc = 9,
DW_LNS_set_prologue_end = 10,
DW_LNS_set_epilogue_begin = 11,
DW_LNS_set_isa = 12,
} DwarfOpcode;
typedef enum DwarfExtendedOpcode : u8
{
DW_LNE_end_sequence = 1,
DW_LNE_set_address = 2,
DW_LNE_set_discriminator = 4,
} DwarfExtendedOpcode;
fn String dwarf_tag_to_string(DwarfTag tag)
{
switch (tag)
@ -1439,6 +1462,8 @@ String dwarf_operation_to_string(DwarfOperation operation)
}
}
// Packing is necessary due to the last fields not completing the alignment of 4
#pragma pack(push, 1)
STRUCT(DwarfLineHeader)
{
u32 unit_length;
@ -1452,8 +1477,8 @@ STRUCT(DwarfLineHeader)
s8 line_base;
u8 line_range;
u8 opcode_base;
// TODO: add dynamic fields
};
#pragma pack(pop)
STRUCT(DwarfCompilationUnit)
{
@ -9542,18 +9567,76 @@ may_be_unused fn void write_elf(Thread* thread, const ObjectOptions* const restr
auto name = elf_get_section_name(builder, strlit(".debug_line"));
u8 data[] = {
0x55, 0x00, 0x00, 0x00, 0x05, 0x00, 0x08, 0x00, 0x37, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0xFB,
0x0E, 0x0D, 0x00, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x01, 0x01,
0x1F, 0x01, 0x00, 0x00, 0x00, 0x00, 0x03, 0x01, 0x1F, 0x02, 0x0F, 0x05, 0x1E, 0x01, 0x14, 0x00,
0x00, 0x00, 0x00, 0x05, 0xAB, 0x89, 0xF5, 0x48, 0x1B, 0xC9, 0xF2, 0xD0, 0x37, 0xE7, 0x88, 0x66,
0x41, 0xE9, 0x19, 0x04, 0x00, 0x05, 0x05, 0x0A, 0x00, 0x09, 0x02, 0x1C, 0x11, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x14, 0x02, 0x03, 0x00, 0x01, 0x01,
*vb_add_struct(&builder->file, DwarfLineHeader) = (DwarfLineHeader) {
.unit_length = 0x55,
.version = 5,
.address_size = 8,
.segment_selector_size = 0,
.header_length = 0x37,
.minimum_instruction_length = 1,
.maximum_operations_per_instruction = 1,
.default_is_stmt = 1,
.line_base = -5,
.line_range = 14,
.opcode_base = 13,
};
auto size = sizeof(data);
// standard opcode lengths
u8 opcode_length_lookup[] = {
[DW_LNS_copy - 1] = 0,
[DW_LNS_advance_pc - 1] = 1,
[DW_LNS_advance_line - 1] = 1,
[DW_LNS_set_file - 1] = 1,
[DW_LNS_set_column - 1] = 1,
[DW_LNS_set_basic_block - 1] = 0,
[DW_LNS_negate_stmt - 1] = 0,
[DW_LNS_const_add_pc - 1] = 0,
[DW_LNS_fixed_advance_pc - 1] = 1,
[DW_LNS_set_prologue_end - 1] = 0,
[DW_LNS_set_epilogue_begin - 1] = 0,
[DW_LNS_set_isa - 1] = 1,
};
memcpy(vb_add(&builder->file, size), data, size);
// TODO: this is just one-byte binary integers. Turn into memcpy?
for (u32 i = 0; i < array_length(opcode_length_lookup); i += 1)
{
uleb128_encode(&builder->file, opcode_length_lookup[i]);
}
// TODO: figure out
{
u8 data[] = {
0x01, 0x01, 0x1F, 0x01, 0x00, 0x00, 0x00, 0x00, 0x03, 0x01, 0x1F, 0x02, 0x0F, 0x05, 0x1E, 0x01, 0x14, 0x00,
0x00, 0x00, 0x00,
};
memcpy(vb_add(&builder->file, sizeof(data)), data, sizeof(data));
}
// TODO: figure out
{
u8 checksum[] = {
0x05, 0xAB, 0x89, 0xF5, 0x48, 0x1B, 0xC9, 0xF2, 0xD0, 0x37, 0xE7, 0x88, 0x66, 0x41, 0xE9, 0x19,
};
memcpy(vb_add(&builder->file, sizeof(checksum)), checksum, sizeof(checksum));
}
{
*vb_add(&builder->file, 1) = DW_LNS_set_file;
*vb_add(&builder->file, 1) = 0;
*vb_add(&builder->file, 1) = DW_LNS_set_column;
*vb_add(&builder->file, 1) = 5;
*vb_add(&builder->file, 1) = DW_LNS_set_prologue_end;
}
// TODO: figure out
{
u8 data[] = { 0x00, 0x09, 0x02, 0x1C, 0x11, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x14, 0x02, 0x03, 0x00, 0x01, 0x01, };
memcpy(vb_add(&builder->file, sizeof(data)), data, sizeof(data));
}
auto size = builder->file.length - offset;
*section_header = (ELFSectionHeader) {
.name_offset = name,