Saturating Multiplier Results On Overflow; Multiplier Instruction Summary - Analog Devices ADSP-BF53x Blackfin Reference

Multiply Accumulators (Multipliers)
• If an overflow or underflow has occurred, the saturate operation
sets the specified Result register to the maximum positive or nega-
tive value. For more information, see the following section.

Saturating Multiplier Results on Overflow

The following bits in
• Bit 16 (
the result has overflowed 32 bits) for the
respectively.
If the bit is cleared (=0), no overflow or underflow has occurred. If
the bit is set (=1), an overflow or underflow has occurred. The
and
AV1S
• Bit 24 (
accumulator result to a register.

Multiplier Instruction Summary

Table 2-10 lists the multiplier instructions. For more information about
assembly language syntax and the effect of multiplier instructions on the
status flags, see
In Table 2-10, note the meaning of these symbols:
• Dreg denotes any Data Register File register.
• Dreg_lo_hi denotes any 16-bit register half in any Data Register
File register.
• Dreg_lo denotes the lower 16 bits of any Data Register File
register.
• Dreg_hi denotes the upper 16 bits of any Data Register File
register.
2-38 ADSP-BF53x/BF56x Blackfin Processor Programming Reference
indicate multiplier overflow status:
ASTAT
) and bit 18 (
AV0 AV1
bits are sticky bits.
) and bit 25 ( ) are set if overflow occurs in extracting the
V VS
Chapter 15, "Arithmetic Operations."
) record overflow condition (whether
and
A0
accumulators,
A1
AV0S