Re: [Patch,avr] Ad PR 54222: Add roundfx, countlsfx to stdfix.h

[Denis Chertykov <chertykov at gmail dot com>]

2013/2/7 Georg-Johann Lay <avr@gjlay.de>:
> This patch adds more fixed-point features from embedded-C:
>
> - roundfx rounding functions
> - countlsfx bit counting functions
> - add implementations of builtins so that an implementation / symbol is
>   available when the address of such a function is taken
>
> The stdfix.h header is cleaned up and just contains defines that map the
> available embedded-C functions to their builtin like
>
> #define roundr   __builtin_avr_roundr
>
> Reasoning is
>
> 1) Is is possible to take the address of roundr
>
> 2) Some builtins might print diagnostics.  If the functions in
>    stdfix.h were implemented as inline functions, the diagnose
>    will point to the implementation in stdfix.h but not to the
>    used code that uses the builtin with odd values.
>
> I found no way to get the location of the argument; EXPR_LOCATION won't work,
> and emitting a warning during built-in folding will show at locations more or
> less randomly distributed (depending on pass) around the correct location...
>
> The type-generic functions are implemented by overloading them.
>
> A new, avr-specific C source is added to libgcc that is used to compile objects
> to be added to libgcc.a.  The objects are compiled by iterating over the
> source, which is not possible with LIB2ADD.  That is: With LIB2ADD, there would
> be a bunch of new C modules, one for each function.  The new iteration scheme
> is similar to iterating over libgcc sources like lib1funcs.S, fp-bit.c,
> fixed-bit.c, etc.
>
> The new test cases pass but they need the following patch to work correctly:
>
> http://gcc.gnu.org/ml/gcc-patches/2013-02/msg00313.html
>
> This is pending review.
>
> Ok for trunk?
>
> Johann
>
>
> gcc/
>         PR target/54222
>         * config/avr/avr.md (unspec) <UNSPEC_ROUND>: Add.
>         * config/avr/avr-fixed.md (ALL4QA, ALL124QA): New mode iterators.
>         (round<mode>3, round<mode>3_const): New expanders for fixed-mode.
>         (*round<mode>3.libgcc): New insns for fixed-modes.
>         * config/avr/builtins.def (ABSxx): Use a non-NULL LIBNAME.
>         (ROUNDxx, COUNTLSxx, BITSxx, xxBITS): New DEF_BUILTINs.
>         (ROUNDFX, COUNTLSFX, ABSFX): New DEF_BUILTINs.
>         * config/avr/stdfix.h (absFX, bitsFX, FXbits): Remove inline
>         implementations.  Define to __builtin_avr_absFX,
>         __builtin_avr_bitsFX, __builtin_avr_FXbits, respectively.
>         (roundFX, countlsFX): Define to __builtin_avr_roundFX,
>         __builtin_avr_countlsFX, respectively.
>         * config/avr/avr-c.c (target.h): Include it.
>         (enum avr_builtin_id): New enum.
>         (avr_resolve_overloaded_builtin): New static function.
>         (avr_register_target_pragmas): Use it to set
>         targetm.resolve_overloaded_builtin.
>         * config/avr/avr.c (avr_init_builtins): Supply myriads of local
>         tree nodes used by DEF_BUILTIN.
>         (avr_expand_builtin) <AVR_BUILTIN_ROUNDxx>: Sanity-check them.
>         (avr_fold_builtin) <AVR_BUILTIN_BITSxx>: Fold to VIEW_COVERT_EXPR.
>         <AVR_BUILTIN_xxBITS>: Same.
>
> libgcc/
>         PR target/54222
>         * config/avr/lib2funcs.c: New C sources for modules for libgcc.a.
>         * config/avr/lib2-object.mk: New iterator to build objects from it.
>         * config/avr/t-avr: Iterate lib2-object.mk to build objects from
>         lib2funcs.c.
>         (LIB2FUNCS_EXCLUDE): Add _clrsbdi2.
>         (LIB1ASMFUNCS): Add: _ssabs_1, _mask1, _ret, _roundqq3, _rounduqq3,
>         _round_s2, _round_u2, _round_2_const, _addmask_2, _round_s4,
>         _round_u4, _round_4_const, _addmask_4, _round_x8, _rounddq3
>         _roundudq3, _roundda3 _rounduda3, _roundta3 _rounduta3.
>         * config/avr/lib1funcs-fixed.S: Implement them.
>
> gcc/testsuite/
>         PR target/54222
>         * gcc.target/avr/torture/builtins-4-roundfx.c: New test.
>         * gcc.target/avr/torture/builtins-5-countlsfx.c: New test.
>
>

Approved.

Denis.