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This is an example of documentation generated by ZigDoc, an alternative to Zig's built-in Auto Doc feature. See also examples in other modes/formats. The project being documented here (as the example) is the Zig standard library. Private Function

findEntry

Private Function
std.debug.Dwarf.Unwind.EhFrameHeader.SearchTable.findEntry
fn findEntry(
            table: *const SearchTable,
            eh_frame_hdr_vaddr: u64,
            pc: u64,
            addr_size_bytes: u8,
            endian: Endian,
        ) !?u64

Returns the vaddr of the FDE for pc, or null if no matching FDE was found.

Params

  • table: *const SearchTable
  • eh_frame_hdr_vaddr: u64
  • pc: u64
  • addr_size_bytes: u8
  • endian: Endian

File

debug/Dwarf/Unwind.zig:144
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        fn findEntry(
            table: *const SearchTable,
            eh_frame_hdr_vaddr: u64,
            pc: u64,
            addr_size_bytes: u8,
            endian: Endian,
        ) !?u64 {
            const table_vaddr = eh_frame_hdr_vaddr + table.offset;
            const entry_size = try entrySize(table.encoding, addr_size_bytes);
            var left: usize = 0;
            var len: usize = table.fde_count;
            while (len > 1) {
                const mid = left + len / 2;
                var entry_reader: Reader = .fixed(table.entries[mid * entry_size ..][0..entry_size]);
                const pc_begin = try readEhPointer(&entry_reader, table.encoding, addr_size_bytes, .{
                    .pc_rel_base = table_vaddr + left * entry_size,
                    .data_rel_base = eh_frame_hdr_vaddr,
                }, endian);
                if (pc < pc_begin) {
                    len /= 2;
                } else {
                    left = mid;
                    len -= len / 2;
                }
            }
            if (len == 0) return null;
            var entry_reader: Reader = .fixed(table.entries[left * entry_size ..][0..entry_size]);
            // Skip past `pc_begin`; we're now interested in the fde offset
            _ = try readEhPointerAbs(&entry_reader, table.encoding.type, addr_size_bytes, endian);
            const fde_ptr = try readEhPointer(&entry_reader, table.encoding, addr_size_bytes, .{
                .pc_rel_base = table_vaddr + left * entry_size,
                .data_rel_base = eh_frame_hdr_vaddr,
            }, endian);
            return fde_ptr;
        }