Reserved bits in the Floating-Point Control and Status Register (FCSR)
should not be implicitly cleared by fedisableexcept or feenableexcept,
there is no reason to. Among these are the 8 condition codes and one of
the two bits reserved for architecture implementers (bits #22 & #21).
As to the latter, there is no reason to treat any of them as reserved
either, they should be user controllable and settable via __fpu_control
override as the user sees fit. For example in processors implemented by
MIPS Technologies, such as the 5Kf or the 24Kf, these bits are used to
change the treatment of denormalised operands and tiny results: bit #22
is Flush Override (FO) and bit #21 is Flush to Nearest (FN). They cause
non-IEEE-compliant behaviour, but some programs may have a use for such
modes of operation; the library should not obstruct such use just as it
does not for the architectural Flush to Zero (FS) bit (bit #24).
Therefore the change adjusts the reserved mask accordingly and also
documents the distinction between bits 22:21 and 20:18.
* sysdeps/powerpc/nofpu/sim-full.c: Add FIXME note about
the need for thread-specific variables preserved across signal
handlers.
* sysdeps/powerpc/nofpu/soft-supp.h: Likewise.
* sysdeps/powerpc/soft-fp/sfp-machine.h: Likewise.
A recently-added test (dlfcn/tststatic5) pointed out that tile was not
properly initializing the variable pagesize in certain cases. This
change just copies the existing code from MIPS.
The sfp-machine.h is based on the gcc version, but extended with
required new macros by comparison with other architectures and by
investigating the hardware support for FP on tile.
This function is now called from dl_open_worker with the GL(dl_load_lock)
lock held and no longer needs local protection. GL(dl_load_lock) also
correctly protects _dl_lookup_symbol_x called here that relies on the
caller to have serialized access to the data structures it uses.
This patch introduces two new convenience functions to set the default
thread attributes used for creating threads. This allows a programmer
to set the default thread attributes just once in a process and then
run pthread_create without additional attributes.
The macros in lowlevellock.h are returning positive errors, but the
users of the macros expect negative. This causes e.g. sem_wait to
sometimes return an error with errno set to -EWOULDBLOCK.
Signed-off-by: Kirk Meyer <kirk.meyer@sencore.com>
Signed-off-by: David Holsgrove <david.holsgrove@xilinx.com>
This turns out to be helpful when doing a from-scratch cross-compile of
gcc and glibc, since you can then do "make install-headers" in glibc
even before you have a functioning tile gcc.
