| Opcode/Instruction | Op/En | 64/32 bit Mode Support | CPUID Feature Flag | Description |
|---|---|---|---|---|
| EVEX.LLIG.F3.MAP5.W0 58 /r VADDSH xmm1{k1}{z}, xmm2, xmm3/m16 {er} | A | V/V | AVX512-FP16 | Add the low FP16 value from xmm3/m16 to xmm2, and store the result in xmm1 subject to writemask k1. Bits 127:16 of xmm2 are copied to xmm1[127:16]. |
| 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 adds the low FP16 value from the source operands 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
VADDSH (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]
ELSEIF *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
VADDSH __m128h _mm_add_round_sh (__m128h a, __m128h b, int rounding);
VADDSH ___m128h _mm_mask_add_round_sh (__m128h src, __mmask8 k, __m128h a, __m128h b, int rounding);
VADDSH ___m128h _mm_maskz_add_round_sh (__mmask8 k, __m128h a, __m128h b, int rounding);
VADDSH ___m128h _mm_add_sh (__m128h a, __m128h b);
VADDSH ___m128h _mm_mask_add_sh (__m128h src, __mmask8 k, __m128h a, __m128h b);
VADDSH ___m128h _mm_maskz_add_sh (__mmask8 k, __m128h a, __m128h b);
SIMD Floating-Point Exceptions
Invalid, Underflow, Overflow, Precision, Denormal.
Other Exceptions
EVEX-encoded instructions, see Table 2-47, “Type E3 Class Exception Conditions.”