Re: [PATCH] c-family: Add more predefined macros for math flags

[Jeff Law <jeffreyalaw@gmail.com>]

On 6/30/2021 2:59 AM, Matthias Kretz wrote:
> Library code, especially in headers, sometimes needs to know how the
> compiler interprets / optimizes floating-point types and operations.
> This information can be used for additional optimizations or for
> ensuring correctness. This change makes -freciprocal-math,
> -fno-signed-zeros, -fno-trapping-math, -fassociative-math, and
> -frounding-math report their state via corresponding pre-defined macros.
>
> Signed-off-by: Matthias Kretz <m.kretz@gsi.de>
>
> gcc/testsuite/ChangeLog:
>
> 	* gcc.dg/associative-math-1.c: New test.
> 	* gcc.dg/associative-math-2.c: New test.
> 	* gcc.dg/no-signed-zeros-1.c: New test.
> 	* gcc.dg/no-signed-zeros-2.c: New test.
> 	* gcc.dg/no-trapping-math-1.c: New test.
> 	* gcc.dg/no-trapping-math-2.c: New test.
> 	* gcc.dg/reciprocal-math-1.c: New test.
> 	* gcc.dg/reciprocal-math-2.c: New test.
> 	* gcc.dg/rounding-math-1.c: New test.
> 	* gcc.dg/rounding-math-2.c: New test.
>
> gcc/c-family/ChangeLog:
>
> 	* c-cppbuiltin.c (c_cpp_builtins_optimize_pragma): Define or
> 	undefine __RECIPROCAL_MATH__, __NO_SIGNED_ZEROS__,
> 	__NO_TRAPPING_MATH__, __ASSOCIATIVE_MATH__, and
> 	__ROUNDING_MATH__ according to the new optimization flags.
>
> gcc/ChangeLog:
>
> 	* cppbuiltin.c (define_builtin_macros_for_compilation_flags):
> 	Define __RECIPROCAL_MATH__, __NO_SIGNED_ZEROS__,
> 	__NO_TRAPPING_MATH__, __ASSOCIATIVE_MATH__, and
> 	__ROUNDING_MATH__ according to their corresponding flags.
> 	* doc/cpp.texi: Document __RECIPROCAL_MATH__,
> 	__NO_SIGNED_ZEROS__, __NO_TRAPPING_MATH__, __ASSOCIATIVE_MATH__,
> 	and __ROUNDING_MATH__.
OK.  Sorry about the long wait.

jeff