Texas Instruments TMS320C6000 Series Reference Manual page 178

Syntax
Opcode
31 29 28 27
creg z dst
3 5
Description
Execution
Pipeline
Instruction Type
Delay Slots
Integer Subtraction Using Addressing Mode
SUBAB (.unit) src2 , src1 , dst
or
SUBAH (.unit) src2 , src1 , dst
or
SUBAW (.unit) src2 , src1 , dst
.unit = .D1 or .D2
Opcode map field used... For operand type...
src2
src1
dst
src2
src1
dst
23 22 18 17
src2
5
src1 is subtracted from src2 . The subtraction defaults to linear mode. Howev-
er, if src2 is one of A4–A7 or B4–B7, the mode can be changed to circular mode
by writing the appropriate value to the AMR (see section 2.6.1 on page 2-9).
src1 is left shifted by 1 or 2 for halfword and word data sizes, respectively.
SUBAB, SUBAH, and SUBAW are byte, halfword, and word mnemonics, re-
spectively. The result is placed in dst .
if (cond) src2 –a src1
else nop
Pipeline
E1
Stage
Read src1, src2
dst
Written
Unit in use .D
Single-cycle
0
sint
sint
sint
sint
ucst5
sint
13 12
src1/cst
op
5
dst
TMS320C62x/C67x Fixed-Point Instruction Set
SUBAB/SUBAH/SUBAW
Unit Opfield
.D1, .D2 Byte: 110001
Halfword: 110101
Word: 111001
.D1, .D2 Byte: 110011
Halfword: 110111
Word: 111011
7 6 5 4 3
1 0 0 0
6
2 1 0
0 s p
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