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Chapter 26. M680x0 Dependent Features

26.4. Floating Point

Packed decimal (P) format floating literals are not supported. Feel free to add the code!

The floating point formats generated by directives are these.

.float

Single

precision floating point constants.

.double

Double

precision floating point constants.

.extend

.ldouble

Extended

precision (

long double

) floating point constants.

26.5. 680x0 Machine Directives

In order to be compatible with the Sun assembler the 680x0 assembler understands the following

directives.

.data1

This directive is identical to a

.data 1

directive.

.data2

This directive is identical to a

.data 2

directive.

.even

This directive is a special case of the

.align

directive; it aligns the output to an even byte

boundary.

.skip

This directive is identical to a

.space

directive.

26.6. Opcodes

26.6.1. Branch Improvement

Certain pseudo opcodes are permitted for branch instructions. They expand to the shortest branch

instruction that reach the target. Generally these mnemonics are made by substituting

j

for

b

at the

start of a Motorola mnemonic.

The following table summarizes the pseudo operations. A

*

flags cases that are more fully described

after the table:

Displacement

+