/
dwarf.cr
44 lines (37 loc) · 868 Bytes
/
dwarf.cr
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require "./dwarf/abbrev"
require "./dwarf/info"
require "./dwarf/line_numbers"
require "./dwarf/strings"
module Debug
module DWARF
def self.read_unsigned_leb128(io : IO)
result = 0_u32
shift = 0
loop do
byte = io.read_byte.not_nil!.to_i
result |= (byte & 0x7f) << shift
break if byte.bit(7) == 0
shift += 7
end
result
end
def self.read_signed_leb128(io : IO)
result = 0_i32
shift = 0
size = 32
byte = 0_u8
loop do
byte = io.read_byte.not_nil!.to_i
result |= (byte & 0x7f) << shift
shift += 7
break if byte.bit(7) == 0
end
# sign bit of byte is 2nd high order bit (0x40)
if (shift < size) && (byte.bit(6) == 1)
# sign extend
result |= -(1 << shift)
end
result
end
end
end