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Provide BOOST_RESTRICT and BOOST_NO_RESTRICT_REFERENCES

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This commit is contained in:
Joel Falcou
2015-11-04 16:48:16 +01:00
parent 94a3bf4f12
commit f020bec68a
2 changed files with 38 additions and 1 deletions
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18
doc/macro_reference.qbk
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@ -209,6 +209,9 @@ Pointers to members don't work when used as template parameters.
The compiler misreads 8.5.1, treating classes as non-aggregate if they
contain private or protected member functions.
]]
[[`BOOST_NO_RESTRICT_REFERENCES`][Compiler][
Compiler-specific `restrict` keyword can not be applied to references.
]]
[[`BOOST_NO_RTTI`][Compiler][
The compiler may (or may not) have the typeid operator, but RTTI on the dynamic type
of an object is not supported.
@ -1136,6 +1139,21 @@ the arguments is itself a macro (see 16.3.1 in C++ standard). This is normally
used to create a mangled name in combination with a predefined macro such a
\_\_LINE__.
]]
[[`BOOST_RESTRICT`][
This macro can be used in place of the compiler specific variant of the C99 `restrict` keyword to
notify the compiler that, for the lifetime of the qualified pointer variable, only it and its
derivative value will be used to gain access to the object it references. This limits the effect of
pointer aliasing and helps the optimizers in generating better code. However, i this condition is
violated, undefined behavior may occurs.
Usage example:
``
void perform_computation( float* BOOST_RESTRICT in, float* BOOST_RESTRICT out )
{
*out = *in * 0.5f;
}
``
]]
[[`BOOST_FORCEINLINE`][
This macro can be used in place of the `inline` keyword to instruct the compiler
that the function should always be inlined.

19
include/boost/config/suffix.hpp
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@ -583,6 +583,25 @@ namespace std{ using ::type_info; }
# define BOOST_GPU_ENABLED
# endif
// BOOST_RESTRICT ---------------------------------------------//
// Macro to use in place of 'restrict' keyword variants
#if !defined(BOOST_RESTRICT)
# if defined(_MSC_VER)
# define BOOST_RESTRICT __restrict
# if !defined(BOOST_NO_RESTRICT_REFERENCES)
# define BOOST_NO_RESTRICT_REFERENCES
# endif
# elif defined(__GNUC__) && __GNUC__ > 3
// Clang also defines __GNUC__ (as 4)
# define BOOST_RESTRICT __restrict__
# else
# define BOOST_RESTRICT
# if !defined(BOOST_NO_RESTRICT_REFERENCES)
# define BOOST_NO_RESTRICT_REFERENCES
# endif
# endif
#endif
// BOOST_FORCEINLINE ---------------------------------------------//
// Macro to use in place of 'inline' to force a function to be inline
#if !defined(BOOST_FORCEINLINE)