Instruction
VCVTSD2SS
Converts the low double of the second source to single, rounding as MXCSR or the instruction selects; the other elements come from the first source.
- Extensions
- Forms
- 4 (2 VEX, 2 EVEX)
- Data
- Intel XED v2026.08.23
Forms
| Instruction | Encoding | Requires |
|---|---|---|
VCVTSD2SS xmm, xmm, m64
VCVTSD2SS_XMMdq_XMMdq_MEMq | VEX.LIG.F2.0F.WIG 5A /r | AVX |
VCVTSD2SS xmm, xmm, xmm
VCVTSD2SS_XMMdq_XMMdq_XMMq | VEX.LIG.F2.0F.WIG 5A /r | AVX |
VCVTSD2SS xmm {k}{z}, xmm, xmm, {er}
VCVTSD2SS_XMMf32_MASKmskw_XMMf64_XMMf64_AVX512 | EVEX.LIG.F2.0F.W1 5A /r | AVX10.1 or AVX512F |
VCVTSD2SS xmm {k}{z}, xmm, m64
VCVTSD2SS_XMMf32_MASKmskw_XMMf64_MEMf64_AVX512 | EVEX.LIG.F2.0F.W1 5A /r | AVX10.1 or AVX512F |
Intrinsics
The C intrinsics of Clang 23.1.2 that compile to VCVTSD2SS, each with the form it compiles to and the Clang options it needs. The forms come from compiling every intrinsic and decoding the result with Intel XED; all intrinsics A–Z explains the method.
| Intrinsic | Compiles to |
|---|---|
_mm_cvt_roundsd_ss
__m128 _mm_cvt_roundsd_ss(__m128 A, __m128d B, const int R) |
|
_mm_cvtsd_ss
__m128 _mm_cvtsd_ss(__m128 __a, __m128d __b) |
|
_mm_mask_cvt_roundsd_ss
__m128 _mm_mask_cvt_roundsd_ss(__m128 W, __mmask8 U, __m128 A, __m128d B, const int R) |
|
_mm_mask_cvtsd_ss
__m128 _mm_mask_cvtsd_ss(__m128 __W, __mmask8 __U, __m128 __A, __m128d __B) |
|
_mm_maskz_cvt_roundsd_ss
__m128 _mm_maskz_cvt_roundsd_ss(__mmask8 U, __m128 A, __m128d B, const int R) |
|
_mm_maskz_cvtsd_ss
__m128 _mm_maskz_cvtsd_ss(__mmask8 __U, __m128 __A, __m128d __B) |
|
CPUID and processors
Each form belongs to an XED ISA set. A form can be used when the processor reports every CPUID bit of one of its ISA set's alternatives.
| ISA set | CPUID | Processors in XED |
|---|---|---|
AVX | AVX | Sandy Bridge, Ivy Bridge, Haswell, Broadwell, Skylake, Comet Lake, Cannon Lake, Ice Lake (client), Tiger Lake, Alder Lake, Arrow Lake, Panther Lake, Nova Lake, Skylake-SP, Cascade Lake, Cooper Lake, Ice Lake (server), Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids, Sierra Forest, Clearwater Forest, Knights Landing, Knights Mill, Bulldozer, Piledriver, Zen, Zen+, Zen 2 |
AVX512F_SCALAR | AVX10.1 or AVX512F | Cannon Lake, Ice Lake (client), Tiger Lake, Nova Lake, Skylake-SP, Cascade Lake, Cooper Lake, Ice Lake (server), Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids, Knights Landing, Knights Mill |
More AVX10.1 instructions
- VCVTPH2PD
- VCVTPH2PS
- VCVTPH2PSX
- VCVTPH2QQ
- VCVTPH2UDQ
- VCVTPH2UQQ
- VCVTPH2UW
- VCVTPH2W
- VCVTPS2DQ
- VCVTPS2PD
- VCVTPS2PH
- VCVTPS2PHX
- VCVTPS2QQ
- VCVTPS2UDQ
- VCVTPS2UQQ
- VCVTQQ2PD
- VCVTQQ2PH
- VCVTQQ2PS
- VCVTSD2SH
- VCVTSD2SI
- VCVTSD2USI
- VCVTSH2SD
- VCVTSH2SI
- VCVTSH2SS
- VCVTSH2USI
- VCVTSI2SD
- VCVTSI2SH
- VCVTSI2SS
- VCVTSS2SD
- VCVTSS2SH
- VCVTSS2SI
- VCVTSS2USI
- VCVTTPD2DQ
- VCVTTPD2QQ
- VCVTTPD2UDQ
- VCVTTPD2UQQ
- VCVTTPH2DQ
- VCVTTPH2QQ
- VCVTTPH2UDQ
- VCVTTPH2UQQ
Sources
- Intel XED v2026.08.23 (commit
0bcb6237345c): forms, encodings, ISA sets, CPUID bits and chip model. - Clang's x86 intrinsic headers, LLVM 23.1.2 (commit
85ac56026243): the intrinsics, their signatures and doc comments, and the Clang of that release, which compiled each of them. - Intel Advanced Vector Extensions 10.2 Architecture Specification, revision 6.0 (361050-006, January 2026)
The tables are derived from Intel XED, Copyright Intel Corporation, licensed under the Apache License 2.0; x86-64.net converted and reformatted them. The intrinsics and their signatures come from Clang, part of the LLVM Project, licensed under the Apache License 2.0 with LLVM Exceptions. The text is our own.