VSQRTSH - Compute Square Root of Scalar FP16 Value

Opcode/ Instruction

Op/ En

64/32 bit Mode Support

CPUID Feature Flag

Description

EVEX.LLIG.F3.MAP5.W0 51 /r VSQRTSH xmm1{k1}{z}, xmm2, xmm3/m16 {er}

A

V/V

AVX512-FP16

Compute square root of the low FP16 value in xmm3/m16 and store the result in xmm1 subject to writemask k1. Bits 127:16 from xmm2 are copied to xmm1[127:16].

Instruction Operand Encoding

Op/En

Tuple

Operand 1

Operand 2

Operand 3

Operand 4

A

Scalar

ModRM:reg (w)

VEX.vvvv (r)

ModRM:r/m (r)

N/A

Description

This instruction performs a scalar FP16 square-root computation on the source operand and stores the FP16 result in the destination operand. Bits 127:16 of the destination operand are copied from the corresponding bits of the first source operand. Bits MAXVL-1:128 of the destination operand are zeroed. The low FP16 element of the destination is updated according to the writemask.

Operation

VSQRTSH dest{k1}, src1, src2 

IF k1[0] or *no writemask*:
   DEST.fp16[0] := SQRT(src2.fp16[0])
ELSE IF *zeroing*:
   DEST.fp16[0] := 0
//else DEST.fp16[0] remains unchanged
DEST[127:16] := src1[127:16]
DEST[MAXVL-1:128] := 0

Intel C/C++ Compiler Intrinsic Equivalent 

VSQRTSH __m128h _mm_mask_sqrt_round_sh (__m128h src, __mmask8 k, __m128h a, __m128h b, const int rounding);
VSQRTSH __m128h _mm_maskz_sqrt_round_sh (__mmask8 k, __m128h a, __m128h b, const int rounding);
VSQRTSH __m128h _mm_sqrt_round_sh (__m128h a, __m128h b, const int rounding);
VSQRTSH __m128h _mm_mask_sqrt_sh (__m128h src, __mmask8 k, __m128h a, __m128h b);
VSQRTSH __m128h _mm_maskz_sqrt_sh (__mmask8 k, __m128h a, __m128h b);
VSQRTSH __m128h _mm_sqrt_sh (__m128h a, __m128h b);

SIMD Floating-Point Exceptions

Invalid, Precision, Denormal

Other Exceptions

EVEX-encoded instructions, see Table 2-47, "Type E3 Class Exception Conditions."