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CVTSS2SD

Convert Scalar Single Precision Floating-Point Value to Scalar Double Precision

stableVMJITAOTinstruction

Encodings

OpcodeInstructionOp/En64-bitCompat/LegacyDescription
F3 0F 5A /rCVTSS2SD xmm1, xmm2/m32AValidValidConvert one single precision floating-point value in xmm2/m32 to one double precision floating-point value in xmm1.
VEX.LIG.F3.0F.WIG 5A /rVCVTSS2SD xmm1, xmm2, xmm3/m32BValidValidConvert one single precision floating-point value in xmm3/m32 to one double precision floating-point value and merge with high bits of xmm2.
EVEX.LLIG.F3.0F.W0 5A /rVCVTSS2SD xmm1 {k1}{z}, xmm2, xmm3/m32{sae}CValidValidConvert one single precision floating-point value in OR AVX10.1 xmm3/m32 to one double precision floating-point value and merge with high bits of xmm2 under writemask k1.

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 lectura y 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

B

  1. modrm.reg escrituraModRM byte, reg field (bits 5-3)
  2. vex.vvvv lecturaVEX prefix, vvvv field (inverted)
  3. modrm.rm lecturaModRM byte, r/m field (bits 2-0); with the SIB byte and the displacement when the mod field asks for them

C

  1. modrm.reg escrituraModRM byte, reg field (bits 5-3)
  2. evex.vvvv lecturaEVEX prefix, vvvv field (inverted)
  3. 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: Tuple1 Scalar

Measured cost

Loading measurements from arch-data...

Description

Converts a single precision floating-point value in the "convert-from" source operand to a double precision floatingpoint value in the destination operand. When the "convert-from" source operand is an XMM register, the single precision floating-point value is contained in the low doubleword of the register. The result is stored in the low quadword of the destination operand.

128-bit Legacy SSE version: The "convert-from" source operand (the second operand) is an XMM register or memory location. Bits (MAXVL-1:64) of the corresponding destination register remain unchanged. The destination operand is an XMM register.

VEX.128 and EVEX encoded versions: The "convert-from" source operand (the third operand) can be an XMM register or a 32-bit memory location. The first source and destination operands are XMM registers. Bits (127:64) of the XMM register destination are copied from the corresponding bits in the first source operand. Bits (MAXVL- 1:128) of the destination register are zeroed.

Software should ensure VCVTSS2SD is encoded with VEX.L=0. Encoding VCVTSS2SD with VEX.L=1 may encounter unpredictable behavior across different processor generations.

Operation

VCVTSS2SD (EVEX Encoded Version)

IF k1[0] or *no writemask*

     THEN DEST[63:0] := Convert_Single_Precision_To_Double_Precision_Floating_Point(SRC2[31:0]);

     ELSE

     IF *merging-masking*         ; merging-masking

           THEN *DEST[63:0] remains unchanged*

           ELSE                   ; zeroing-masking

           THEN DEST[63:0] = 0

     FI;

FI;

DEST[127:64] := SRC1[127:64]

DEST[MAXVL-1:128] := 0

VCVTSS2SD (VEX.128 Encoded Version)
DEST[63:0] := Convert_Single_Precision_To_Double_Precision_Floating_Point(SRC2[31:0])
DEST[127:64] := SRC1[127:64]
DEST[MAXVL-1:128] := 0

CVTSS2SD (128-bit Legacy SSE Version)
DEST[63:0] := Convert_Single_Precision_To_Double_Precision_Floating_Point(SRC[31:0]);
DEST[MAXVL-1:64] (Unmodified)

Intel C/C++ compiler intrinsics

VCVTSS2SD __m128d _mm_cvt_roundss_sd(__m128d a, __m128 b, int r);
VCVTSS2SD __m128d _mm_mask_cvt_roundss_sd(__m128d s, __mmask8 m, __m128d a,__m128 b, int r);
VCVTSS2SD __m128d _mm_maskz_cvt_roundss_sd(__mmask8 k, __m128d a, __m128 a, int r);
VCVTSS2SD __m128d _mm_mask_cvtss_sd(__m128d s, __mmask8 m, __m128d a,__m128 b);
VCVTSS2SD __m128d _mm_maskz_cvtss_sd(__mmask8 m, __m128d a,__m128 b);
CVTSS2SD __m128d_mm_cvtss_sd(__m128d a, __m128 a);

SIMD Floating-Point Exceptions

Invalid, Denormal.

Other Exceptions

VEX-encoded instructions, see Table 2-20, "Type 3 Class Exception Conditions." EVEX-encoded instructions, see Table 2-49, "Type E3 Class Exception Conditions."

Sources