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       Explicit_conversions_with_convert_T() - Explicit type conversions using convert_T()

       convert_destType(sourceType) destType
       (sourceType) destTypen


       Explicit conversions may be performed using the convert_destType(sourceType) suite of
       functions. These provide a full set of type conversions between supported types (see
       scalarDataTypes(3clc)) except for the following types: bool, half, size_t, ptrdiff_t,
       intptr_t, uintptr_t, and void.

       The number of elements in the source and destination vectors must match.

       The behavior of the conversion may be modified by one or two optional modifiers that
       specify saturation for out-of-range inputs and rounding behavior.

       The full form of the scalar convert function is:


       The full form of the vector convert function is:

       Conversions are available for the following scalar types: char, uchar, short, ushort, int,
       uint, long, ulong, float, and built-in vector types derived therefrom. The operand and
       result type must have the same number of elements. The operand and result type may be the
       same type in which case the conversion has no effect on the type or value of an

       Conversions between integer types follow the conversion rules specified in sections and of the C99 specification except for out-of-range behavior and
       saturated conversions which are described in section below.  Rounding Modes.PP
       Conversions to and from floating-point type shall conform to IEEE-754 rounding rules.
       Conversions may have an optional rounding mode modifier described in the table below.

       │ModifierRounding Mode Description        │
       │                             │                                  │
       │       _rte                  │        Round to nearest even     │
       │                             │                                  │
       │       _rtz                  │        Round towards zero        │
       │                             │                                  │
       │       _rtp                  │        Round toward positive     │
       │                             │        infinity                  │
       │                             │                                  │
       │       _rtn                  │        Round toward negative     │
       │                             │        infinity                  │
       │                             │                                  │
       │       no modifier specified │        Use the default rounding  │
       │                             │        mode for this destination │
       │                             │        type, _rtz for conversion │
       │                             │        to integers or the        │
       │                             │        default rounding mode for │
       │                             │        conversion to             │
       │                             │        floating-point types.     │

       By default, conversions to integer type use the _rtz (round toward zero) rounding mode and
       conversions to floating-point type use the default rounding mode. The only default
       floating-point rounding mode supported is round to nearest even, i.e the default rounding
       mode will be _rte for floating-point types.

       For conversions to floating-point format, when a finite source value exceeds the maximum
       representable finite floating-point destination value, the rounding mode will affect
       whether the result is the maximum finite floating point value or infinity of same sign as
       the source value, per IEEE-754 rules for rounding.

       Out-of-Range Behavior and Saturated Conversions

       When the conversion operand is either greater than the greatest representable destination
       value or less than the least representable destination value, it is said to be
       out-of-range. The result of out-of-range conversion is determined by the conversion rules
       specified by the C99 specification in section 6.3. When converting from a floating-point
       type to integer type, the behavior is implementation-defined.

       Conversions to integer type may opt to convert using the optional saturated mode by
       appending the _sat modifier to the conversion function name. When in saturated mode,
       values that are outside the representable range shall clamp to the nearest representable
       value in the destination format. (NaN should be converted to 0).

       Conversions to floating-point type shall conform to IEEE-754 rounding rules. The _sat
       modifier may not be used for conversions to floating-point formats.

       In the following example, convert_int4 converts a uchar4 vector u to an int4 vector c:

       uchar4 u; int4   c = convert_int4(u);

       In the following example, convert_int converts a float scalar f to an int scalar i:

       float   f; int    i = convert_int(f);


       short4  s;

       // negative values clamped to 0 ushort4 u =
       convert_ushort4_sat( s );

       // values > CHAR_MAX converted to CHAR_MAX //
       values < CHAR_MIN converted to CHAR_MIN char4 c
       = convert_char4_sat( s );


       float4 f;

       // values implementation defined for // f >
       INT_MAX, f < INT_MIN or NaN int4   i =
       convert_int4( f );

       // values > INT_MAX clamp to INT_MAX, values <
       INT_MIN clamp // to INT_MIN. NaN should produce

       // The _rtz rounding mode is // used to produce
       the integer values.  int4   i2 =
       convert_int4_sat( f );

       // similar to convert_int4, except that //
       floating-point values are rounded to the nearest
       // integer instead of truncated int4   i3 =
       convert_int4_rte( f );

       // similar to convert_int4_sat, except that //
       floating-point values are rounded to the //
       nearest integer instead of truncated int4   i4 =
       convert_int4_sat_rte( f );


       int4   i;

       // convert ints to floats using the default
       rounding mode.  float4 f = convert_float4( i );

       // convert ints to floats. integer values that
       cannot // be exactly represented as floats
       should round up to the // next representable
       float.  float4 f = convert_float4_rtp( i );


       OpenCL Specification[1]


       scalarDataTypes(3clc), vectorDataTypes(3clc)


       The Khronos Group


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        1. OpenCL Specification
           page 207, section 6.2.3 - Explicit Conversions