ARM Architecture Reference Manual ARMv7-A and ARMv7-R edition

Application Level Programmers’ Model
A2.7.8 Pseudocode details of floating-point operations
This section contains pseudocode definitions of the floating-point operations used by the architecture.
Generation of specific floating-point values
The following pseudocode functions generate specific floating-point values. The sign argument of
FPInfinity(), FPMaxNormal(), and FPZero() is '0' for the positive version and '1' for the negative version.
// FPZero()
// ========
bits(N) FPZero(bit sign, integer N)
assert N == 16 || N == 32 || N == 64;
if N == 16 then
return sign : ‘00000 0000000000’;
elsif N == 32 then
return sign : ‘00000000 00000000000000000000000’;
else
return sign : ‘00000000000 0000000000000000000000000000000000000000000000000000’;
// FPTwo()
// =======
bits(N) FPTwo(integer N)
assert N == 32 || N == 64;
if N == 32 then
return ‘0 10000000 00000000000000000000000’;
else
return ‘0 10000000000 0000000000000000000000000000000000000000000000000000’;
// FPThree()
// =========
bits(N) FPThree(integer N)
assert N == 32 || N == 64;
if N == 32 then
return ‘0 10000000 10000000000000000000000’;
else
return ‘0 10000000000 1000000000000000000000000000000000000000000000000000’;
// FPMaxNormal()
// =============
bits(N) FPMaxNormal(bit sign, integer N)
assert N == 16 || N == 32 || N == 64;
if N == 16 then
return sign : ‘11110 1111111111’;
elsif N == 32 then
return sign : ‘11111110 11111111111111111111111’;
else
return sign : ‘11111111110 1111111111111111111111111111111111111111111111111111’;
A2-46 Copyright © 1996-1998, 2000, 2004-2008 ARM Limited. All rights reserved. ARM DDI 0406B