Texas Instruments TMS320C54x, User Manual

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Terminate Local Symbol Block
.newblock
4-73 Assembler Directives
Syntax
.newblock
Description The .newblock directive undefines any local labels currently defined. Local
labels, by nature, are temporary; the .newblock directive resets them and
terminates their scope.
A local label is a label in the form $n, where n is a single decimal digit. A local
label, like other labels, points to an instruction word. Unlike other labels, local
labels cannot be used in expressions. Local labels are not included in the
symbol table.
After a local label has been defined and (perhaps) used, you should use the
.newblock directive to reset it. The .text, .data, and named sections also reset
local labels. Local labels that are defined within an include file are not valid out-
side of the local file.
Example This example shows how the local label $1 is declared, reset, and then
declared again.
1 .ref ADDRA, ADDRB, ADDRC
2 0076 B .set 76h
3
4 000000 1000! LABEL1: LD ADDRA, A
5 000001 F010 SUB #B, A
000002 0076
6 000003 F843 BC $1, ALT
000004 0008’
7 000005 1000! LD ADDRB, A
8 000006 F073 B $2
000007 0009’
9
10 000008 1000! $1 LD ADDRA, A
11 000009 0000! $2 ADD ADDRC, A
12 .newblock ; Undefine $1 to reuse
13 00000a F843 BC $1, ALT
00000b 000D’
14 00000c 8000! STL A, ADDRC
15 00000d F495 $1 NOP