Intel® oneAPI DPC++/C++ Compiler Developer Guide and Reference

Development Reference Guides

Contents

Rules for Operators

To use operators with the
Ivec
 classes you must use one of the following three syntax conventions, where
  • [
    operator
     ] represents an operator (for example, &, |, or ^ )
  • [
    Ivec_Class
     ] represents an
    Ivec
     class
  • R
    ,
    A
    ,
    B
     variables are declared using the pertinent
    Ivec
     classes
Convention One
Syntax: 
 [ Ivec_Class ] R = [ Ivec_Class ] A [ operator ][ Ivec_Class ] B
Example: 
 I64vec1 R = I64vec1 A & I64vec1 B;
Convention Two
Syntax: 
[ Ivec_Class ] R =[ operator ] ([ Ivec_Class ] A,[ Ivec_Class ] B)
Example: 
 I64vec1 R = andnot(I64vec1 A, I64vec1 B);
Convention Three
Syntax: 
[ Ivec_Class ] R [ operator ]= [ Ivec_Class ] A
Example: 
 I64vec1 R &= I64vec1 A;
Summary of Rules for Major Operators
The following table lists automatic and explicit sign and size typecasting.
Explicit
 means that it is illegal to mix different types without an explicit typecasting.
Automatic
 means that you can mix types freely and the compiler will do the typecasting for you.
Operators
Sign Typecasting
Size Typecasting
Other Typecasting Requirements
Assignment
N/A
N/A
N/A
Logical
Automatic
Automatic
(to left)
Explicit typecasting is required for different types used in non-logical expressions on the right side of the assignment.
Addition and Subtraction
Automatic
Explicit
N/A
Multiplication
Automatic
Explicit
N/A
Shift
Automatic
Explicit
Casting Required to ensure arithmetic shift.
Compare
Automatic
Explicit
Explicit casting is required for signed classes for the less-than or greater-than operations.
Conditional Select
Automatic
Explicit
Explicit casting is required for signed classes for less-than or greater-than operations.

Data Declaration and Initialization

The following table lists literal examples of constructor declarations and data type initialization for all class sizes. All values are initialized with the most significant element on the left and the least significant to the right.
Operation
Class
Syntax
Declaration
M128
I128vec1 A; Iu8vec16 A;
Declaration
M64
I64vec1 A; Iu8vec8 A;
__m128
 Initialization
M128
I128vec1 A(__m128 m); Iu16vec8(__m128 m);
__m64
 Initialization
M64
I64vec1 A(__m64 m);Iu8vec8 A(__m64 m);
__int64
 Initialization
M64
I64vec1 A = __int64 m; Iu8vec8 A =__int64 m;
int i
 Initialization
M64
I64vec1 A = int i; Iu8vec8 A = int i;
int
 Initialization
I32vec2
I32vec2 A(int A1, int A0);
Is32vec2 A(signed int A1, signed int A0);
Iu32vec2 A(unsigned int A1, unsigned int A0);
int
 Initialization
I32vec4
I32vec4 A(int A3, int A2, int A1, int A0);
Is32vec4 A(signed int A3, ..., signed int A0);
Iu32vec4 A(unsigned int A3, ..., unsigned int A0);
short int
 Initialization
I16vec4
I16vec4 A(short A3, short A2, short A1, short A0);
Is16vec4 A(signed short A3, ..., signed short A0);
Iu16vec4 A(unsigned short A3, ..., unsigned short A0);
short int
 Initialization
I16vec8
I16vec8 A(short A7, short A6, ..., short A1, short A0);
Is16vec8 A(signed A7, ..., signed short A0);
Iu16vec8 A(unsigned short A7, ..., unsigned short A0);
char
 Initialization
I8vec8
I8vec8 A(char A7, char A6, ..., char A1, char A0);
Is8vec8 A(signed char A7, ..., signed char A0);
Iu8vec8 A(unsigned char A7, ..., unsigned char A0);
char
 Initialization
I8vec16
I8vec16 A(char A15, ..., char A0);
Is8vec16 A(signed char A15, ..., signed char A0);
Iu8vec16 A(unsigned char A15, ..., unsigned char A0);

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.