millfork/doc/abi/generated-labels.md

Guide to generated label names

Many Millfork constructs generate labels. Knowing what they mean can be useful when reading the generated assembly code.

Every generated label is of form .xx__11111 where 11111 is a sequential number and xx is the type:

• ah – optimized addition of carry

• an – logical conjunction short-circuiting

• bc – array bounds checking (-fbounds-checking)

• c8 – constant #8 for BIT when immediate addressing is not available

• co – greater-than comparison

• cp – equality comparison for larger types

• de – decrement for larger types

• do – beginning of a do-while statement

• ds – decimal right shift operation

• el – beginning of the "else" block in an if statement

• ew – end of a while statement

• fi – end of an if statement

• he – beginning of the body of a while statement

• in – increment for larger types

• is – optimized addition of carry using undocumented instructions

• od – end of a do-while statement

• or – logical alternative short-circuiting

• sx – sign extension, from a smaller signed type to a larger type

• th – beginning of the "then" block in an if statement

• wh – beginning of a while statement