vcvtdq2ps

Convert Packed Doubleword to Packed Single

VCVTDQ2PS ymm1, ymm2/m256

Converts four 32-bit integers to floats.

Details

Converts four packed 32-bit signed doubleword integers to four packed single-precision floating-point values. The conversion uses the current MXCSR rounding mode; inexact results may set the PE (precision exception) flag in MXCSR. Available in 128-bit (XMM) and 256-bit (YMM) variants; the 256-bit form converts eight integers. No legacy flags are modified.

Pseudocode Operation

if VEX.L = 0:
  for i in 0 to 1:
    xmm1[i] ← convert_dword_to_float(xmm2[i])
else:
  for i in 0 to 3:
    ymm1[i] ← convert_dword_to_float(ymm2[i])
update_MXCSR_flags()

Example

VCVTDQ2PS ymm1, ymm2/m256

Encoding

Binary Layout
VEX
+0
0F
+3
5B
+4
 
Format VEX
Opcode VEX.256.0F.WIG 5B /r
Extension AVX

Operands

  • dest
    256-bit YMM AVX register
  • src
    256-bit YMM AVX register or Memory operand

Reference (Intel® SDM)

Instruction Forms

Opcode Instruction Op/En 64/32-bit Mode CPUID Description
NP 0F 5B /r CVTDQ2PS xmm1, xmm2/m128 A V/V SSE2 Convert four packed signed doubleword integers from xmm2/mem to four packed single precision floating-point values in xmm1.
VEX.128.0F.WIG 5B /r VCVTDQ2PS xmm1, xmm2/m128 A V/V AVX Convert four packed signed doubleword integers from xmm2/mem to four packed single precision floating-point values in xmm1.
VEX.256.0F.WIG 5B /r VCVTDQ2PS ymm1, ymm2/m256 A V/V AVX Convert eight packed signed doubleword integers from ymm2/mem to eight packed single precision floating-point values in ymm1.
EVEX.128.0F.W0 5B /r VCVTDQ2PS xmm1 {k1}{z}, xmm2/m128/m32bcst B V/V (AVX512VL AND AVX512F) OR AVX10.1 Convert four packed signed doubleword integers from xmm2/m128/m32bcst to four packed single precision floating-point values in xmm1with writemask k1.
EVEX.256.0F.W0 5B /r VCVTDQ2PS ymm1 {k1}{z}, ymm2/m256/m32bcst B V/V (AVX512VL AND AVX512F) OR AVX10.1 Convert eight packed signed doubleword integers from ymm2/m256/m32bcst to eight packed single precision floating-point values in ymm1with writemask k1.
EVEX.512.0F.W0 5B /r VCVTDQ2PS zmm1 {k1}{z}, zmm2/m512/m32bcst {er} B V/V AVX512F OR AVX10.1 Convert sixteen packed signed doubleword integers from zmm2/m512/m32bcst to sixteen packed single precision floating-point values in zmm1with writemask k1.

Instruction Operand Encoding

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

Description

Converts four, eight or sixteen packed signed doubleword integers in the source operand to four, eight or sixteen packed single precision floating-point values in the destination operand. EVEX encoded versions: The source operand can be a ZMM/YMM/XMM register, a 512/256/128-bit memory location or a 512/256/128-bit vector broadcasted from a 32-bit memory location. The destination operand is a ZMM/YMM/XMM register conditionally updated with writemask k1. VEX.256 encoded version: The source operand is a YMM register or 256- bit memory location. The destination operand is a YMM register. Bits (MAXVL-1:256) of the corresponding register destination are zeroed. VEX.128 encoded version: The source operand is an XMM register or 128- bit memory location. The destination operand is a XMM register. The upper bits (MAXVL-1:128) of the corresponding register destination are zeroed. 128-bit Legacy SSE version: The source operand is an XMM register or 128- bit memory location. The destination operand is an XMM register. The upper Bits (MAXVL-1:128) of the corresponding register destination are unmodified. VEX.vvvv and EVEX.vvvv are reserved and must be 1111b, otherwise instructions will #UD. CVTDQ2PS—Convert Packed Doubleword Integers to Packed Single Precision Floating-Point Values Vol. 2A 3-211

Operation

VCVTDQ2PS (EVEX Encoded Versions) When SRC Operand is a Register
(KL, VL) = (4, 128), (8, 256), (16, 512)
IF (VL = 512) AND (EVEX.b = 1)
THEN
SET_ROUNDING_MODE_FOR_THIS_INSTRUCTION(EVEX.RC);  ; refer to Table 15-4 in the Intel® 64 and IA-32 Architectures
Software Developer’s Manual, Volume 1
ELSE
SET_ROUNDING_MODE_FOR_THIS_INSTRUCTION(MXCSR.RC);  ; refer to Table 15-4 in the Intel® 64 and IA-32 Architectures
Software Developer’s Manual, Volume 1
FI;

FOR j := 0 TO KL-1
i := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+31:i] :=
Convert_Integer_To_Single_Precision_Floating_Point(SRC[i+31:i])
ELSE
IF *merging-masking*                                 ; merging-masking
THEN *DEST[i+31:i] remains unchanged*
ELSE                                                         ; zeroing-masking
DEST[i+31:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:VL] := 0

VCVTDQ2PS (EVEX Encoded Versions) When SRC Operand is a Memory Source
(KL, VL) = (4, 128), (8, 256), (16, 512)

FOR j := 0 TO KL-1
i := j * 32
IF k1[j] OR *no writemask*
THEN
IF (EVEX.b = 1)
THEN
DEST[i+31:i] :=
Convert_Integer_To_Single_Precision_Floating_Point(SRC[31:0])
ELSE
DEST[i+31:i] :=
Convert_Integer_To_Single_Precision_Floating_Point(SRC[i+31:i])
FI;
ELSE
IF *merging-masking*                                 ; merging-masking
THEN *DEST[i+31:i] remains unchanged*
ELSE                                                         ; zeroing-masking
DEST[i+31:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:VL] := 0





CVTDQ2PS—Convert Packed Doubleword Integers to Packed Single Precision Floating-Point Values                                         Vol. 2A 3-212
VCVTDQ2PS (VEX.256 Encoded Version)
DEST[31:0] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[31:0])
DEST[63:32] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[63:32])
DEST[95:64] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[95:64])
DEST[127:96] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[127:96)
DEST[159:128] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[159:128])
DEST[191:160] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[191:160])
DEST[223:192] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[223:192])
DEST[255:224] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[255:224)
DEST[MAXVL-1:256] := 0

VCVTDQ2PS (VEX.128 Encoded Version)
DEST[31:0] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[31:0])
DEST[63:32] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[63:32])
DEST[95:64] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[95:64])
DEST[127:96] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[127z:96)
DEST[MAXVL-1:128] := 0

CVTDQ2PS (128-bit Legacy SSE Version)
DEST[31:0] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[31:0])
DEST[63:32] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[63:32])
DEST[95:64] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[95:64])
DEST[127:96] := Convert_Integer_To_Single_Precision_Floating_Point(SRC[127z:96)
DEST[MAXVL-1:128] (unmodified)

Intel C/C++ Compiler Intrinsic Equivalent

VCVTDQ2PS __m512 _mm512_cvtepi32_ps( __m512i a);
VCVTDQ2PS __m512 _mm512_mask_cvtepi32_ps( __m512 s, __mmask16 k, __m512i a);
VCVTDQ2PS __m512 _mm512_maskz_cvtepi32_ps( __mmask16 k, __m512i a);
VCVTDQ2PS __m512 _mm512_cvt_roundepi32_ps( __m512i a, int r);
VCVTDQ2PS __m512 _mm512_mask_cvt_roundepi_ps( __m512 s, __mmask16 k, __m512i a, int r);
VCVTDQ2PS __m512 _mm512_maskz_cvt_roundepi32_ps( __mmask16 k, __m512i a, int r);
VCVTDQ2PS __m256 _mm256_mask_cvtepi32_ps( __m256 s, __mmask8 k, __m256i a);
VCVTDQ2PS __m256 _mm256_maskz_cvtepi32_ps( __mmask8 k, __m256i a);
VCVTDQ2PS __m128 _mm_mask_cvtepi32_ps( __m128 s, __mmask8 k, __m128i a);
VCVTDQ2PS __m128 _mm_maskz_cvtepi32_ps( __mmask8 k, __m128i a);
CVTDQ2PS __m256 _mm256_cvtepi32_ps (__m256i src)
CVTDQ2PS __m128 _mm_cvtepi32_ps (__m128i src)

Exceptions

SIMD Floating-Point Exceptions

Precision.

Other Exceptions

VEX-encoded instructions, see Table 2-19, “Type 2 Class Exception Conditions.” EVEX-encoded instructions, see Table 2-48, “Type E2 Class Exception Conditions.” Additionally: #UD If VEX.vvvv != 1111B or EVEX.vvvv != 1111B. CVTDQ2PS—Convert Packed Doubleword Integers to Packed Single Precision Floating-Point Values Vol. 2A 3-213