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Ssub – Texas Instruments TMS320C67X/C67X+ DSP User Manual

Page 295

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Subtract Two Signed Integers With Saturation

SSUB

3-235

Instruction Set

SPRU733

Pipeline
Stage

E1

Read

src1, src2

Written

dst

Unit in use

.L

Instruction Type

Single-cycle

Delay Slots

0

See Also

SUB

Example 1

SSUB .L2

B1,B2,B3

Before instruction

1 cycle after instruction

2 cycles after instruction

B1 5A2E 51A3h 1512984995

B1 5A2E 51A3h

B1 5A2E 51A3h

B2 802A 3FA2h −2144714846

B2 802A 3FA2h

B2 802A 3FA2h

B3 xxxx xxxxh

B3 7FFF FFFFh 2147483647

B3 7FFF FFFFh

CSR 0001 0100h

CSR 0001 0100h

CSR 0001 0300h Saturated

Example 2

SSUB .L1

A0,A1,A2

Before instruction

1 cycle after instruction

2 cycles after instruction

A0 4367 71F2h 1130852850

A0 4367 71F2h

A0 4367 71F2h

A1 5A2E 51A3h 1512984995

A1 5A2E 51A3h

A1 5A2E 51A3h

A2 xxxx xxxxh

A2 E939 204Fh −382132145

A2 E939 204Fh

CSR 0001 0100h

CSR 0001 0100h

CSR 0001 0100h Not saturated

Pipeline