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Source code

VCVTPH2W

Convert Packed FP16 Values to Signed Word Integers

stableVMJITAOTinstruction

Encodings

OpcodeInstructionOp/En64-bitCompat/LegacyDescription
EVEX.128.66.MAP5.W0 7D /rVCVTPH2W xmm1{k1}{z}, xmm2/m128/m16bcstAValidValidConvert packed FP16 values in AND AVX512VL) xmm2/m128/m16bcst to signed word integers, OR AVX10.1 and store the result in xmm1.
EVEX.256.66.MAP5.W0 7D /rVCVTPH2W ymm1{k1}{z}, ymm2/m256/m16bcstAValidValidConvert packed FP16 values in AND AVX512VL) ymm2/m256/m16bcst to signed word integers, OR AVX10.1 and store the result in ymm1.
EVEX.512.66.MAP5.W0 7D /rVCVTPH2W zmm1{k1}{z}, zmm2/m512/m16bcst {er}AValidValidConvert packed FP16 values in OR AVX10.1 zmm2/m512/m16bcst to signed word integers, and store the result in zmm1.

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. 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: Full

Measured cost

Loading measurements from arch-data...

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 8000H 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 intrinsics

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 2-48, "Type E2 Class Exception Conditions."

Sources