Chapter 16. D30V Dependent Features

105

Since

$

has no special meaning, you may use it in symbol names.

16.2.4. Guarded Execution

as

supports the full range of guarded execution directives for each instruction. Just append the direc 

tive after the instruction proper. The directives are:

/tx

Execute the instruction if flag f0 is true.

/fx

Execute the instruction if flag f0 is false.

/xt

Execute the instruction if flag f1 is true.

/xf

Execute the instruction if flag f1 is false.

/tt

Execute the instruction if both flags f0 and f1 are true.

/tf

Execute the instruction if flag f0 is true and flag f1 is false.

16.2.5. Register Names

You can use the predefined symbols

r0

through

r63

to refer to the D30V registers. You can also use

sp

as an alias for

r63

and

link

as an alias for

r62

. The accumulators are

a0

and

a1

.

The D30V also has predefined symbols for these control registers and status bits:

psw

Processor Status Word

bpsw

Backup Processor Status Word

pc

Program Counter

bpc

Backup Program Counter

rpt_c

Repeat Count

rpt_s

Repeat Start address