On Tue, Dec 29, 2015 at 11:38 AM, Michael Meissner <meiss...@linux.vnet.ibm.com> wrote: > This patch enables support of the __float128 software emulation functions in > libgcc. The patch is reworked from previous versions of this patch (listed as > patch #8). > > This patch adds support for declaring emulation functions that either use the > software emulation functions from the soft-fp subdirectory converted for > PowerPC __float128 via sed, or by using the hardware instructions that will be > present in ISA 3.0 (power9). Thus if you compile code for power7/power8 and > run it on a power9 system, it use the hardware support when running on power9. > > I removed the old comparison functions that was in previous versions of this > patch, and instead went with the standard EQ, GE, LE, and UNORD software > emulation support (patch #10 changes the compiler to use these functions). > > This patch adds support to use the hardware rounding modes and exceptions for > software emulation that was done by Steven Munroe and Tulio Magno. > > The __float128 support is only enabled on 64-bit PowerPC Linux systems, where > the base compler targets at least power7. On big endian systems, you can use > __float128 in 32-bit mode, but the support functions are not built on a purely > 32-bit system. > > At the moment, there is no support for converting between decimal types and > __float128, nor for the complex __float128 support. These are being worked > on, > and should be done in the GCC 7.x time frame. However, it is important to add > the software emulation support in GCC 6.x now so that most users that want to > use IEEE 128-bit floating point can use it, and that we can work on the glibc > issues to fully support __float128 in the GCC 7.x time frame. There might be > problems that need to be fixed, but without the libgcc changes, nobody can use > __float128. > > I have done bootstraps on a big-endian power7 system and little-endian power8 > system with no regressions. I have also built a compiler on a SLES 11.3 > system > to make sure that it builds on systems without the ISA 3.0 instructions (in > this case, the ifunc resolver always returns the software emulation function). > Is this ok to install in the tree along with IEEE patch #10? > > 2015-12-29 Michael Meissner <meiss...@linux.vnet.ibm.com> > Steven Munroe (munro...@linux.vnet.ibm.com) > Tulio Magno Quites Machado Filho <tuli...@br.ibm.com> > > * config/rs6000/floattikf-sw.c: New file to convert signed 128-bit > integers to IEEE 128-bit floating point. > > * config/rs6000/float128-hw.c: New file for ISA 3.0 IEEE 128-bit > floating point hardware support. > > * config/rs6000/fixkfti-sw.c: New file to convert IEEE 128-bit > floating point to signed 128-bit integer. > > * config/rs6000/float128-ifunc.c: New file to pick either IEEE > 128-bit floating point software emulation or use ISA 3.0 hardware > support if it is available. > > * config/rs6000/fixunskfti-sw.c: New file to convert IEEE 128-bit > floating point to unsigned 128-bit integer. > > * config/rs6000/extendkftf2-sw.c: New file to convert IBM extended > double to IEEE 128-bit floating point. > > * config/rs6000/floatuntikf-sw.c: New file to convert unsigned > 128-bit integer to IEEE 128-bit floating point. > > * config/rs6000/trunctfkf2-sw.c: New file to convert IEEE 128-bit > floating point to IBM extended double. > > * config/rs6000/t-float128: New file to build IEEE 128-bit > floating point emulator functions. > > * config/rs6000/t-float128-hw: New file to build IEEE 128-bit > floating point emulator functions using ISA 3.0 hardware > instructions. > > * config/rs6000/sfp-exceptions.c: New file to provide exception > support for IEEE 128-bit floating point. > > * config/rs6000/quad-float128.h: New file to support IEEE 128-bit > floating point. > > * config/rs6000/float128-sed: New file to convert TF names to KF > names for PowerPC IEEE 128-bit floating point support. > > * config/rs6000/sfp-machine.h (_FP_W_TYPE_SIZE): Use 64-bit types > when building on 64-bit systems, or when VSX is enabled. > (_FP_W_TYPE): Likewise. > (_FP_WS_TYPE): Likewise. > (_FP_I_TYPE): Likewise. > (TItype): Define on 64-bit systems. > (UTItype): Likewise. > (TI_BITS): Likewise. > (_FP_MUL_MEAT_D): Add support for using 64-bit types. > (_FP_MUL_MEAT_Q): Likewise. > (_FP_DIV_MEAT_D): Likewise. > (_FP_DIV_MEAT_Q): Likewise. > (_FP_NANFRAC_D): Likewise. > (_FP_NANFRAC_Q): Likewise. > (ISA_BIT): Add exception support. > (FP_EX_INVALID): Likewise. > (FP_EX_OVERFLOW): Likewise. > (FP_EX_UNDERFLOW): Likewise. > (FP_EX_DIVZERO): Likewise. > (FP_EX_INEXACT): Likewise. > (FP_EX_ALL): Likewise. > (__sfp_handle_exceptions): Likewise. > (FP_HANDLE_EXCEPTIONS): Likewise. > (FP_RND_NEAREST): Likewise. > (FP_RND_ZERO): Likewise. > (FP_RND_PINF): Likewise. > (FP_RND_MINF): Likewise. > (FP_RND_MASK): Likewise. > (_FP_DECL_EX): Likewise. > (FP_INIT_ROUNDMODE): Likewise. > (FP_ROUNDMODE): Likewise. > > * libgcc/config.host (powerpc*-*-linux*): If compiler can compile > VSX code, enable IEEE 128-bit floating point. > > * Makefile.in (EXTRA_CLEAN): Add extra files to be delete with > make clean. > (FLAGS_TO_PASS): Likewise. > (clean rule): Likewise. > > * configure.ac (powerpc*-*-linux*): Check whether the PowerPC > compiler can do __float128. > * configure: Regenerate.
The revised patch is okay with me in theory, but I would like Joseph to check that this is the way he wants the solution addressed and implemented. Also, I cannot approve the Makefile.in change. Thanks, David
