VDIVSH—Divide Scalar FP16 Values

Opcode/Instruction Op/En 64/32 bit Mode Support CPUID Feature Flag Description
EVEX.LLIG.F3.MAP5.W0 5E /r VDIVSH xmm1{k1}{z}, xmm2, xmm3/m16 {er} A V/V AVX512-FP16 Divide low FP16 value in xmm2 by low FP16 value in xmm3/m16, and store the result in xmm1 subject to writemask k1. Bits 127:16 of 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


This instruction divides the low FP16 value from the first source operand by the corresponding value in the second source operand, storing 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.


VDIVSH (EVEX Encoded Versions)

IF EVEX.b = 1 and SRC2 is a register:




IF k1[0] OR *no writemask*:

DEST.fp16[0] := SRC1.fp16[0] / 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

VDIVSH __m128h _mm_div_round_sh (__m128h a, __m128h b, int rounding);

VDIVSH __m128h _mm_mask_div_round_sh (__m128h src, __mmask8 k, __m128h a, __m128h b, int rounding);

VDIVSH __m128h _mm_maskz_div_round_sh (__mmask8 k, __m128h a, __m128h b, int rounding);

VDIVSH __m128h _mm_div_sh (__m128h a, __m128h b);

VDIVSH __m128h _mm_mask_div_sh (__m128h src, __mmask8 k, __m128h a, __m128h b);

VDIVSH __m128h _mm_maskz_div_sh (__mmask8 k, __m128h a, __m128h b);

SIMD Floating-Point Exceptions

Invalid, Underflow, Overflow, Precision, Denormal, Zero.

Other Exceptions

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