mips.c (DIRECT_BUILTIN_PURE): New macro.

mips.c (DIRECT_BUILTIN_PURE): New macro.

        * config/mips/mips.c (DIRECT_BUILTIN_PURE): New macro. Add a
        pure qualifier to the built-in.
        (MSA_BUILTIN_PURE): New macro. Add a pure qualifier to the MSA
        built-ins.
        (struct mips_builtin_description): Add is_pure flag.
        (mips_init_builtins): Mark built-in as pure if the flag in the
        corresponding mips_builtin_description struct is set.

        * gcc.target/mips/mips-builtins-pure.c: New test.

From-SVN: r277534