INSTRUCTION SET REFERENCE
6-19
6
6.2.10
bbc, bbs
Mnemonic:
bbc
Check Bit and Branch If Clear
bbs
Check Bit and Branch If Set
Format:
bb*
bitpos,
src,
targ
reg/lit
reg
disp
Description:
Checks bit (designated by bitpos) in src and sets AC register condition code
according to src value. The processor then performs conditional branch to
instruction specified with targ, based on condition code state.
For
bbc
, when selected bit in src is clear, the processor sets condition code to
000
2
and branches to instruction specified by targ; otherwise, it sets condition
code to 010
2
and goes to next instruction.
For
bbs
, when selected bit is set, the processor sets condition code to 010
2
and branches to targ; otherwise, it sets condition code to 000
2
and goes to
next instruction.
targ can be no farther than -2
12
to (2
12
- 4) bytes from current IP. When using
the Intel i960 processor assembler, targ must be a label which specifies target
instruction’s IP.
Action:
bbs:
if((src & 2**(bitpos%32)) == 1)
{
AC.cc = 010
2
;
temp[31:2] = sign_extension(targ[12:2]);
IP[31:2] = IP[31:2] + temp[31:2];
IP[1:0] = 0;
}
else
AC.cc = 000
2
;
bbc:
if((src & 2**(bitpos%32)) == 0)
{
AC.cc = 000
2
;
temp[31:2] = sign_extension(targ[12:2]);
IP[31:2] = IP[31:2] + temp[31:2];
IP[1:0] = 0;
}
else
AC.cc = 010
2
;
Faults:
STANDARD Refer
to
section 6.1.6, “Faults” (pg. 6-5)
.
Содержание i960 Jx
Страница 1: ...Release Date December 1997 Order Number 272483 002 i960 Jx Microprocessor Developer s Manual ...
Страница 24: ......
Страница 25: ...1 INTRODUCTION ...
Страница 26: ......
Страница 35: ...2 DATA TYPES AND MEMORY ADDRESSING MODES ...
Страница 36: ......
Страница 46: ......
Страница 47: ...3 PROGRAMMING ENVIRONMENT ...
Страница 48: ......
Страница 73: ...4 CACHE AND ON CHIP DATA RAM ...
Страница 74: ......
Страница 85: ...5 INSTRUCTION SET OVERVIEW ...
Страница 86: ......
Страница 111: ...6 INSTRUCTION SET REFERENCE ...
Страница 112: ......
Страница 195: ...INSTRUCTION SET REFERENCE 6 83 6 Opcode mov 5CCH REG movl 5DCH REG movt 5ECH REG movq 5FCH REG See Also LOAD STORE lda ...
Страница 233: ...7 PROCEDURE CALLS ...
Страница 234: ......
Страница 256: ......
Страница 257: ...8 FAULTS ...
Страница 258: ......
Страница 291: ...9 TRACING AND DEBUGGING ...
Страница 292: ......
Страница 309: ...10 TIMERS ...
Страница 310: ......
Страница 324: ......
Страница 325: ...11 INTERRUPTS ...
Страница 326: ......
Страница 369: ...12 INITIALIZATION AND SYSTEM REQUIREMENTS ...
Страница 370: ......
Страница 412: ......
Страница 413: ...13 MEMORY CONFIGURATION ...
Страница 414: ......
Страница 429: ...14 EXTERNAL BUS ...
Страница 430: ......
Страница 468: ......
Страница 469: ...15 TEST FEATURES ...
Страница 470: ......
Страница 493: ...A CONSIDERATIONS FOR WRITING PORTABLE CODE ...
Страница 494: ......
Страница 502: ......
Страница 503: ...B OPCODES AND EXECUTION TIMES ...
Страница 504: ......
Страница 515: ...C MACHINE LEVEL INSTRUCTION FORMATS ...
Страница 516: ......
Страница 523: ...D REGISTER AND DATA STRUCTURES ...
Страница 524: ......
Страница 550: ......
Страница 551: ...GLOSSARY ...
Страница 552: ......
Страница 561: ...INDEX ...
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Страница 578: ......