5.10.9. VRECPE and VRSQRTE

VRECPE (Vector Reciprocal Estimate) finds an approximate reciprocal of each element in a vector, and places the results in a second vector.

VRSQRTE (Vector Reciprocal Square Root Estimate) finds an approximate reciprocal square root of each element in a vector, and places the results in a second vector.

Syntax

Vop{cond}.datatype Qd, Qm
Vop{cond}.datatype Dd, Dm

where:

op

must be either RECPE or RSQRTE.

cond

is an optional condition code (see Condition codes).

datatype

must be either U32 or F32.

Qd, Qm

are the destination vector and the operand vector, for a quadword operation.

Dd, Dm

are the destination vector and the operand vector, for a doubleword operation.

Results for out-of-range inputs

Table 5.10 shows the results where input values are out of range.

Table 5.10. Results for out-of-range inputs

 Operand element (VRECPE)Operand element (VRSQRTE)Result element
Integer<= 0x7FFFFFFF<= 0x3FFFFFFF0xFFFFFFFF
Floating-pointNaNNaN, Negative Normal, Negative InfinityDefault NaN
Negative 0, Negative DenormalNegative 0, Negative DenormalNegative Infinity [a]
Positive 0, Positive DenormalPositive 0, Positive DenormalPositive Infinity [a]
Positive infinityPositive infinityPositive 0
Negative infinity Negative 0

[a] The Division by Zero exception bit in the FPSCR (FPSCR[1]) is set


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