cvttps2dq

Convert with Truncation Packed Single-Precision to Packed Doubleword Integers

CVTTPS2DQ xmm1, xmm2/m128

Converts four floats to 32-bit integers (Truncated).

Details

Converts four packed single-precision floating-point values to four packed signed 32-bit integers by truncating toward zero (discarding fractional part). If any input is NaN or out of range, the result is 0x80000000. Operates on 128-bit XMM registers without using MXCSR rounding mode.

Pseudocode Operation

dest[0:31] ← Truncate(src[0:31]); dest[32:63] ← Truncate(src[32:63]); dest[64:95] ← Truncate(src[64:95]); dest[96:127] ← Truncate(src[96:127]);

Example

CVTTPS2DQ xmm1, xmm2/m128

Encoding

Binary Layout
F3
+0
0F
+1
5B
+2
 
Format SSE2
Opcode F3 0F 5B
Extension SSE2

Operands

  • dest
    XMM
  • src
    XMM/Mem

Reference (Intel® SDM)

Instruction Forms

Opcode Instruction Op/En 64/32-bit Mode CPUID Description
F3 0F 5B /r CVTTPS2DQ xmm1, xmm2/m128 A V/V SSE2 Convert four packed single precision floating-point values from xmm2/mem to four packed signed doubleword values in xmm1 using truncation.
VEX.128.F3.0F.WIG 5B /r VCVTTPS2DQ xmm1, xmm2/m128 A V/V AVX Convert four packed single precision floating-point values from xmm2/mem to four packed signed doubleword values in xmm1 using truncation.
VEX.256.F3.0F.WIG 5B /r VCVTTPS2DQ ymm1, ymm2/m256 A V/V AVX Convert eight packed single precision floating-point values from ymm2/mem to eight packed signed doubleword values in ymm1 using truncation.
EVEX.128.F3.0F.W0 5B /r VCVTTPS2DQ xmm1 {k1}{z}, xmm2/m128/m32bcst B V/V AVX512VL AVX512F Convert four packed single precision floating-point values from xmm2/m128/m32bcst to four packed signed doubleword values in xmm1 using truncation subject to writemask k1.
EVEX.256.F3.0F.W0 5B /r VCVTTPS2DQ ymm1 {k1}{z}, ymm2/m256/m32bcst B V/V AVX512VL AVX512F Convert eight packed single precision floating-point values from ymm2/m256/m32bcst to eight packed signed doubleword values in ymm1 using truncation subject to writemask k1.
EVEX.512.F3.0F.W0 5B /r VCVTTPS2DQ zmm1 {k1}{z}, zmm2/m512/m32bcst {sae} B V/V AVX512F Convert sixteen packed single precision floating-point values from zmm2/m512/m32bcst to sixteen packed signed doubleword values in zmm1 using truncation subject to 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 single precision floating-point values in the source operand to four, eight or sixteen signed doubleword integers in the destination operand. When a conversion is inexact, a truncated (round toward zero) value is returned. If a converted result is larger than the maximum signed doubleword integer, the floating-point invalid exception is raised, and if this exception is masked, the indefinite integer value 80000000H is returned. EVEX encoded versions: The source operand is 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. The upper bits (MAXVL-1:256) of the corresponding ZMM 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 ZMM 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 ZMM register destination are unmodified. Note: VEX.vvvv and EVEX.vvvv are reserved and must be 1111b otherwise instructions will #UD. CVTTPS2DQ—Convert With Truncation Packed Single Precision Floating-Point Values to Packed Signed Doubleword Integer Values Vol. 2A 3-249

Operation

VCVTTPS2DQ (EVEX Encoded Versions) When SRC Operand is a Register
(KL, VL) = (4, 128), (8, 256), (16, 512)

FOR j := 0 TO KL-1
i := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+31:i] :=
Convert_Single_Precision_Floating_Point_To_Integer_Truncate(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

VCVTTPS2DQ (EVEX Encoded Versions) When SRC Operand is a Memory Source
(KL, VL) = (4, 128), (8, 256), (16, 512)

FOR j := 0 TO 15
i := j * 32
IF k1[j] OR *no writemask*
THEN
IF (EVEX.b = 1)
THEN
DEST[i+31:i] :=
Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[31:0])
ELSE
DEST[i+31:i] :=
Convert_Single_Precision_Floating_Point_To_Integer_Truncate(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

VCVTTPS2DQ (VEX.256 Encoded Version)
DEST[31:0] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[31:0])
DEST[63:32] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[63:32])
DEST[95:64] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[95:64])
DEST[127:96] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[127:96)
DEST[159:128] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[159:128])
DEST[191:160] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[191:160])
DEST[223:192] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[223:192])
DEST[255:224] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[255:224])



CVTTPS2DQ—Convert With Truncation Packed Single Precision Floating-Point Values to Packed Signed Doubleword Integer Values       Vol. 2A 3-250
VCVTTPS2DQ (VEX.128 Encoded Version)
DEST[31:0] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[31:0])
DEST[63:32] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[63:32])
DEST[95:64] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[95:64])
DEST[127:96] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[127:96])
DEST[MAXVL-1:128] := 0

CVTTPS2DQ (128-bit Legacy SSE Version)
DEST[31:0] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[31:0])
DEST[63:32] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[63:32])
DEST[95:64] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[95:64])
DEST[127:96] := Convert_Single_Precision_Floating_Point_To_Integer_Truncate(SRC[127:96])
DEST[MAXVL-1:128] (unmodified)

Intel C/C++ Compiler Intrinsic Equivalent

VCVTTPS2DQ __m512i _mm512_cvttps_epi32( __m512 a);
VCVTTPS2DQ __m512i _mm512_mask_cvttps_epi32( __m512i s, __mmask16 k, __m512 a);
VCVTTPS2DQ __m512i _mm512_maskz_cvttps_epi32( __mmask16 k, __m512 a);
VCVTTPS2DQ __m512i _mm512_cvtt_roundps_epi32( __m512 a, int sae);
VCVTTPS2DQ __m512i _mm512_mask_cvtt_roundps_epi32( __m512i s, __mmask16 k, __m512 a, int sae);
VCVTTPS2DQ __m512i _mm512_maskz_cvtt_roundps_epi32( __mmask16 k, __m512 a, int sae);
VCVTTPS2DQ __m256i _mm256_mask_cvttps_epi32( __m256i s, __mmask8 k, __m256 a);
VCVTTPS2DQ __m256i _mm256_maskz_cvttps_epi32( __mmask8 k, __m256 a);
VCVTTPS2DQ __m128i _mm_mask_cvttps_epi32( __m128i s, __mmask8 k, __m128 a);
VCVTTPS2DQ __m128i _mm_maskz_cvttps_epi32( __mmask8 k, __m128 a);
VCVTTPS2DQ __m256i _mm256_cvttps_epi32 (__m256 a)
CVTTPS2DQ __m128i _mm_cvttps_epi32 (__m128 a)

Exceptions

SIMD Floating-Point Exceptions

Invalid, 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. CVTTPS2DQ—Convert With Truncation Packed Single Precision Floating-Point Values to Packed Signed Doubleword Integer Values Vol. 2A 3-251