Intel XENIX 286 Programmers Guide (86) - Tenox.tc

XENIX Programming
Floating-Point Directives
. float float
.double float
as: A sse m bier
The .float and .double directives accept one or more floating-point numbers as operands
and allocate storage for each number. A floating-point number has the form
[-] integer. fraction [ E [ - ] exponent ]
where integer is a decimal number, fraction is a combination of decimal digits, and
exponent is an decimal nu mber. Examples of these directives are
.float
.double
.float
25.1
1.03E12
-34718.235E4
The .float and .double directives allocate a different number of bytes. The .float sets
aside four bytes, while .double sets aside eight.
Global Directive
.globl name
The .globl directive makes the text or data associated with name globally known to all
files in a program. name must be explicitly defined by assignment or by appearance as a
label in exactly one file. All other files that wish to access this name must use .globl to
give the name global meaning; no other definition is allowed in these files. The link
editor ld resolves all global references to name when the final program is created. If
more than one name is given, they must be separated with com mas (,).
Segment Directives
.text
.data
.bss
The .text, .data, and .bss directives cause the assembler to copy subsequent · instruction
or data code (or allocated storage) to the text, data, or bss segment respectively. The
offset of the location counter is set to the previous value for that segment and
subsequent statements are processed as defined in the earlier section "Assembly
Segments."
The directives may be used any nu mber of times within a program. The offset for each
segment is initially set to 0. Changing a segment causes the current offset to be saved.
Restoring a segment causes the old offset to be restored. Thus, each segment is copied
as a contiguous block even if the original source statements were not contiguous.
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