CVTPD2PS—Convert Packed Double-Precision FP Values to Packed Single-Precision FP Values

Opcode/Instruction Op/En 64/32-bit Mode CPUID Feature Flag Description

66 0F 5A /r

CVTPD2PS xmm1, xmm2/m128

RM V/V SSE2 Convert two packed double-precision floating-point values in xmm2/m128 to two packed single-precision floating-point values in xmm1.

VEX.128.66.0F.WIG 5A /r

VCVTPD2PS xmm1, xmm2/m128

RM V/V AVX Convert two packed double-precision floating-point values in xmm2/mem to two single-precision floating-point values in xmm1.

VEX.256.66.0F.WIG 5A /r

VCVTPD2PS xmm1, ymm2/m256

RM V/V AVX Convert four packed double-precision floating-point values in ymm2/mem to four single-precision floating-point values in xmm1.

Instruction Operand Encoding

Op/En Operand 1 Operand 2 Operand 3 Operand 4
RM ModRM:reg (w) ModRM:r/m (r) NA NA

Description

Converts two packed double-precision floating-point values in the source operand (second operand) to two packed single-precision floating-point values in the destination operand (first operand).

When a conversion is inexact, the value returned is rounded according to the rounding control bits in the MXCSR register.

In 64-bit mode, use of the REX.R prefix permits this instruction to access additional registers (XMM8-XMM15).

128-bit Legacy SSE version: The source operand is an XMM register or 128- bit memory location. The destination operation is an XMM register. Bits[127:64] of the destination XMM register are zeroed. However, the upper bits (VLMAX-1:128) of the corresponding YMM register destination are unmodified.

VEX.128 encoded version: The source operand is an XMM register or 128- bit memory location. The destination operation is a YMM register. The upper bits (VLMAX-1:64) of the corresponding YMM register destination are zeroed.

VEX.256 encoded version: The source operand is a YMM register or 256- bit memory location. The destination operation is an XMM register. The upper bits (255:128) of the corresponding YMM register destination are zeroed.

Note: In VEX-encoded versions, VEX.vvvv is reserved and must be 1111b otherwise instructions will #UD.

SRC

X3

X2

X1

X0

DEST

0

X3

X2

X1

X0

Figure 3-12. VCVTPD2PS (VEX.256 encoded version)

Operation

CVTPD2PS (128-bit Legacy SSE version)

DEST[31:0] ← Convert_Double_Precision_To_Single_Precision_Floating_Point(SRC[63:0])
DEST[63:32] ← Convert_Double_Precision_To_Single_Precision_Floating_Point(SRC[127:64])
DEST[127:64] ← 0
DEST[VLMAX-1:128] (unmodified)

VCVTPD2PS (VEX.128 encoded version)

DEST[31:0] ← Convert_Double_Precision_To_Single_Precision_Floating_Point(SRC[63:0])
DEST[63:32] ← Convert_Double_Precision_To_Single_Precision_Floating_Point(SRC[127:64])
DEST[VLMAX-1:64] ← 0

VCVTPD2PS (VEX.256 encoded version)

DEST[31:0] ← Convert_Double_Precision_To_Single_Precision_Floating_Point(SRC[63:0])
DEST[63:32] ← Convert_Double_Precision_To_Single_Precision_Floating_Point(SRC[127:64])
DEST[95:64] ← Convert_Double_Precision_To_Single_Precision_Floating_Point(SRC[191:128])
DEST[127:96] ← Convert_Double_Precision_To_Single_Precision_Floating_Point(SRC[255:192)
DEST[255:128]← 0

Intel C/C++ Compiler Intrinsic Equivalent

CVTPD2PS:

__m128 _mm_cvtpd_ps(__m128d a)

CVTPD2PS:

__m256 _mm256_cvtpd_ps (__m256d a)

SIMD Floating-Point Exceptions

Overflow, Underflow, Invalid, Precision, Denormal.

Other Exceptions

See Exceptions Type 2; additionally

#UD If VEX.vvvv ≠ 1111B.