x86doc › VCVTPH2W - Convert Packed FP16 Values to Signed Word Integers

VCVTPH2W—Convert Packed FP16 Values to Signed Word Integers

Opcode/Instruction	Op/En	64/32 bit Mode Support	CPUID Feature Flag	Description
EVEX.128.66.MAP5.W0 7D /r VCVTPH2W xmm1{k1}{z}, xmm2/m128/m16bcst	A	V/V	AVX512-FP16 AVX512VL	Convert packed FP16 values in xmm2/m128/m16bcst to signed word integers, and store the result in xmm1.
EVEX.256.66.MAP5.W0 7D /r VCVTPH2W ymm1{k1}{z}, ymm2/m256/m16bcst	A	V/V	AVX512-FP16 AVX512VL	Convert packed FP16 values in ymm2/m256/m16bcst to signed word integers, and store the result in ymm1.
EVEX.512.66.MAP5.W0 7D /r VCVTPH2W zmm1{k1}{z}, zmm2/m512/m16bcst {er}	A	V/V	AVX512-FP16	Convert packed FP16 values in zmm2/m512/m16bcst to signed word integers, and store the result in zmm1.

Instruction Operand Encoding

Op/En	Tuple	Operand 1	Operand 2	Operand 3	Operand 4
A	Full	ModRM:reg (w)	ModRM:r/m (r)	N/A	N/A

Description

This instruction converts packed FP16 values in the source operand to signed word integers in the destination operand.

When a conversion is inexact, the value returned is rounded according to the rounding control bits in the MXCSR register or the embedded rounding control bits. If a converted result cannot be represented in the destination format, the floating-point invalid exception is raised, and if this exception is masked, the indefinite integer value is returned.

The destination elements are updated according to the writemask.

Operation

VCVTPH2W DEST, SRC

VL = 128, 256 or 512

KL := VL / 16

IF *SRC is a register* and (VL = 512) and (EVEX.b = 1):

SET_RM(EVEX.RC)

ELSE:

SET_RM(MXCSR.RC)

FOR j := 0 TO KL-1:

IF k1[j] OR *no writemask*:

IF *SRC is memory* and EVEX.b = 1:

tsrc := SRC.fp16[0]

ELSE

tsrc := SRC.fp16[j]

DEST.word[j] := Convert_fp16_to_integer16(tsrc)

ELSE IF *zeroing*:

DEST.word[j] := 0

// else dest.word[j] remains unchanged

DEST[MAXVL-1:VL] := 0

Intel C/C++ Compiler Intrinsic Equivalent

VCVTPH2W __m512i _mm512_cvt_roundph_epi16 (__m512h a, int rounding);

VCVTPH2W __m512i _mm512_mask_cvt_roundph_epi16 (__m512i src, __mmask32 k, __m512h a, int rounding);

VCVTPH2W __m512i _mm512_maskz_cvt_roundph_epi16 (__mmask32 k, __m512h a, int rounding);

VCVTPH2W __m128i _mm_cvtph_epi16 (__m128h a);

VCVTPH2W __m128i _mm_mask_cvtph_epi16 (__m128i src, __mmask8 k, __m128h a);

VCVTPH2W __m128i _mm_maskz_cvtph_epi16 (__mmask8 k, __m128h a);

VCVTPH2W __m256i _mm256_cvtph_epi16 (__m256h a);

VCVTPH2W __m256i _mm256_mask_cvtph_epi16 (__m256i src, __mmask16 k, __m256h a);

VCVTPH2W __m256i _mm256_maskz_cvtph_epi16 (__mmask16 k, __m256h a);

VCVTPH2W __m512i _mm512_cvtph_epi16 (__m512h a);

VCVTPH2W __m512i _mm512_mask_cvtph_epi16 (__m512i src, __mmask32 k, __m512h a);

VCVTPH2W __m512i _mm512_maskz_cvtph_epi16 (__mmask32 k, __m512h a);

SIMD Floating-Point Exceptions

Invalid, Precision.

Other Exceptions

EVEX-encoded instructions, see Table 2-46, “Type E2 Class Exception Conditions.”