Move tilegx, tilepro, and linux-generic from ports to libc.

I've moved the TILE-Gx and TILEPro ports to the main sysdeps hierarchy,
along with the linux-generic ports infrastructure.  Beyond the README
update, the move was just

    git mv ports/sysdeps/tile sysdeps/tile
    git mv ports/sysdeps/unix/sysv/linux/tile \
      sysdeps/unix/sysv/linux/tile
    git mv ports/sysdeps/unix/sysv/linux/generic \
      sysdeps/unix/sysv/linux/generic

I updated the relevant ChangeLogs along the lines of the ARM move
in commit c6bfe5c4d75 and tested the 64-bit tilegx build to confirm that
there were no changes in "objdump -dr" output in the shared objects.

1 files changed, 31 insertions, 0 deletions

diff --git a/sysdeps/tile/math_private.h b/sysdeps/tile/math_private.h
new file mode 100644
index 0000000000..90dcc3f866
--- /dev/null
+++ b/sysdeps/tile/math_private.h
@@ -0,0 +1,31 @@
+#ifndef _MATH_PRIVATE_H
+
+/* Internally, we suppress any use of exception or rounding other
+   than what is supported by the hardware.  This does mean that some
+   code will silently fail to report exceptions, set rounding mode
+   as expected, etc., but it allows math code to compile that otherwise
+   wouldn't (such as math/s_fma.c) and so is valuable.
+
+   We intentionally ignore the "exception" arguments of functions that
+   take an exception, since we can't even evaluate the argument
+   without causing a build failure.  The extra level of statement
+   expression wrapping avoids "statement with no effect" warnings.
+   Since the callers don't check for errors anyway, we just claim
+   success in every case.
+
+   The overrides for libc_ functions must happen before we include
+   the generic math_private.h, and the overrides for regular
+   <fenv.h> functions must happen afterwards, to avoid clashing with
+   the declarations of those functions.  */
+
+#define libc_fesetround(rnd)			({ 0; })
+#define libc_fetestexcept(exc)			({ 0; })
+#define libc_feholdexcept_setround(env, exc)	({ (void) (env); 0; })
+#define libc_feupdateenv_test(env, exc)		({ (void) (env); 0; })
+
+#include_next <math_private.h>
+
+#define feraiseexcept(excepts)			({ 0; })
+#define feclearexcept(exc)			({ 0; })
+
+#endif