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Source code

VDIVSH

Divide Scalar FP16 Values

stableVMJITAOTinstruction

Encodings

OpcodeInstructionOp/En64-bitCompat/LegacyDescription
EVEX.LLIG.F3.MAP5.W0 5E /rVDIVSH xmm1{k1}{z}, xmm2, xmm3/m16 {er}AValidValidDivide low FP16 value in xmm2 by low FP16 OR AVX10.1 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].

Operand encoding

Each mode is a value of the Op/En column above. It says which field of the encoded instruction carries each operand, in the order they are written, and whether the instruction reads it, writes it or both.

A

  1. modrm.reg escrituraModRM byte, reg field (bits 5-3)
  2. vex.vvvv lecturaVEX prefix, vvvv field (inverted)
  3. modrm.rm lecturaModRM byte, r/m field (bits 2-0); with the SIB byte and the displacement when the mod field asks for them

Tupla: Scalar

Measured cost

Loading measurements from arch-data...

Description

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.

Operation

VDIVSH (EVEX Encoded Versions)
IF EVEX.b = 1 and SRC2 is a register:

    SET_RM(EVEX.RC)
ELSE

    SET_RM(MXCSR.RC)

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 intrinsics

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 2-49, "Type E3 Class Exception Conditions."

Sources