* hooks.h (hook_tree_tree_tree_bool_null): Rename to...
(hook_tree_tree_int_treep_bool_null): ...this. Update signature.
* hooks.c: Likewise.
* target-def.h (TARGET_FOLD_BUILTIN): Define to
hook_tree_tree_int_treep_bool_null.
* target.h: (struct gcc_target): Update signature of fold_builtin
field.
* doc/tm.texi (TARGET_FOLD_BUILTIN): Update description and signature.
* builtins.c (fold_call_expr): Pass call_expr_nargs and CALL_EXPR_ARGP
instead of the call expression.
(fold_builtin_call_array): Pass n and argarray directly.
(fold_call_stmt): Pass nargs and gimple_call_arg_ptr instead of
consing a list.
* config/alpha/alpha.c (alpha_fold_builtin): Update signature. Lift
MAX_ARGS check out of the loop. Delete declaration of `arity', declare
`i' and use it in place of `arity'.
* config/sparc/sparc.c (sparc_fold_builtin): Update signature.
Dereference `args' directly.
* config/xtensa/xtensa (xtensa_fold_builtin): Likewise.