21.18 DCFD and DCFDU

The DCFD directive allocates memory for word-aligned double-precision floating-point numbers, and defines the initial runtime contents of the memory. DCFDU is the same, except that the memory alignment is arbitrary.


{label} DCFD{U} fpliteral{,fpliteral}...


is a double-precision floating-point literal.


Double-precision numbers occupy two words and must be word aligned to be used in arithmetic operations. The assembler inserts up to three bytes of padding before the first defined number, if necessary, to achieve four-byte alignment.

Use DCFDU if you do not require alignment.

The word order used when converting fpliteral to internal form is controlled by the floating-point architecture selected. You cannot use DCFD or DCFDU if you select the --fpu none option.

The range for double-precision numbers is:

  • Maximum 1.79769313486231571e+308.

  • Minimum 2.22507385850720138e-308.


        DCFD    1E308,-4E-100
        DCFDU   10000,-.1,3.1E26
Non-ConfidentialPDF file icon PDF versionDUI0801J
Copyright © 2014–2017, 2019 Arm Limited or its affiliates. All rights reserved.