Re: Short-cut generation of simple built-in functions

["H.J. Lu" <hjl.tools@gmail.com>]

On Sat, Nov 7, 2015 at 5:31 AM, Richard Sandiford
<richard.sandiford@arm.com> wrote:
> This patch short-circuits the builtins.c expansion code for a particular
> gimple call if:
>
> - the function has an associated internal function
> - the target implements that internal function
> - the call has no side effects
>
> This allows a later patch to remove the builtins.c code, once calls with
> side effects have been handled.
>
> Tested on x86_64-linux-gnu, aarch64-linux-gnu and arm-linux-gnueabi.
> OK to install?
>
> Thanks,
> Richard
>
>
> gcc/
>         * builtins.h (called_as_built_in): Declare.
>         * builtins.c (called_as_built_in): Make external.
>         * internal-fn.h (expand_internal_call): Define a variant that
>         specifies the internal function explicitly.
>         * internal-fn.c (expand_load_lanes_optab_fn)
>         (expand_store_lanes_optab_fn, expand_ANNOTATE, expand_GOMP_SIMD_LANE)
>         (expand_GOMP_SIMD_VF, expand_GOMP_SIMD_LAST_LANE)
>         (expand_GOMP_SIMD_ORDERED_START, expand_GOMP_SIMD_ORDERED_END)
>         (expand_UBSAN_NULL, expand_UBSAN_BOUNDS, expand_UBSAN_VPTR)
>         (expand_UBSAN_OBJECT_SIZE, expand_ASAN_CHECK, expand_TSAN_FUNC_EXIT)
>         (expand_UBSAN_CHECK_ADD, expand_UBSAN_CHECK_SUB)
>         (expand_UBSAN_CHECK_MUL, expand_ADD_OVERFLOW, expand_SUB_OVERFLOW)
>         (expand_MUL_OVERFLOW, expand_LOOP_VECTORIZED)
>         (expand_mask_load_optab_fn, expand_mask_store_optab_fn)
>         (expand_ABNORMAL_DISPATCHER, expand_BUILTIN_EXPECT, expand_VA_ARG)
>         (expand_UNIQUE, expand_GOACC_DIM_SIZE, expand_GOACC_DIM_POS)
>         (expand_GOACC_LOOP, expand_GOACC_REDUCTION, expand_direct_optab_fn)
>         (expand_unary_optab_fn, expand_binary_optab_fn): Add an internal_fn
>         argument.
>         (internal_fn_expanders): Update prototype.
>         (expand_internal_call): Define a variant that specifies the
>         internal function explicitly. Use it to implement the previous
>         interface.
>         * cfgexpand.c (expand_call_stmt): Try to expand calls to built-in
>         functions as calls to internal functions.
>

This caused:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68488


H.J.