[Bug target/85358] PowerPC: Using -mabi=ieeelongdouble -mcpu=power9 breaks __ibm128

[meissner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85358

--- Comment #2 from Michael Meissner <meissner at gcc dot gnu.org> ---
Author: meissner
Date: Fri Jun 22 14:19:45 2018
New Revision: 261893

URL: https://gcc.gnu.org/viewcvs?rev=261893&root=gcc&view=rev
Log:
[gcc]
2018-06-22  Michael Meissner  <meissner@linux.ibm.com>

        Back port from trunk
        2018-06-18  Michael Meissner  <meissner@linux.ibm.com>

        PR target/85358
        * config/rs6000/rs6000-modes.def (toplevel): Rework the 128-bit
        floating point modes, so that IFmode is numerically greater than
        TFmode, which is greater than KFmode using FRACTIONAL_FLOAT_MODE
        to declare the ordering.  This prevents IFmode from being
        converted to TFmode when long double is IEEE 128-bit on an ISA 3.0
        machine.  Include rs6000-modes.h to share the fractional values
        between genmodes* and the rest of the compiler.
        (IFmode): Likewise.
        (KFmode): Likewise.
        (TFmode): Likewise.
        * config/rs6000/rs6000-modes.h: New file.
        * config/rs6000/rs6000.c (rs6000_debug_reg_global): Change the
        meaning of rs6000_long_double_size so that 126..128 selects an
        appropriate 128-bit floating point type.
        (rs6000_option_override_internal): Likewise.
        * config/rs6000/rs6000.h (toplevel): Include rs6000-modes.h.
        (TARGET_LONG_DOUBLE_128): Change the meaning of
        rs6000_long_double_size so that 126..128 selects an appropriate
        128-bit floating point type.
        (LONG_DOUBLE_TYPE_SIZE): Update comment.
        * config/rs6000/rs6000.md (trunciftf2): Correct the modes of the
        source and destination to match the standard usage.
        (truncifkf2): Likewise.
        (copysign<mode>3, IEEE iterator): Rework copysign of float128 on
        ISA 2.07 to use an explicit clobber, instead of passing in a
        temporary.
        (copysign<mode>3_soft): Likewise.

[libgcc]
2018-06-22  Michael Meissner  <meissner@linux.ibm.com>

        Back port from trunk
        2018-06-18  Michael Meissner  <meissner@linux.ibm.com>

        * config/rs6000/t-float128 (FP128_CFLAGS_SW): Compile float128
        support modules with -mno-gnu-attribute.
        * config/rs6000/t-float128-hw (FP128_CFLAGS_HW): Likewise.


Added:
    branches/gcc-8-branch/gcc/config/rs6000/rs6000-modes.h
Modified:
    branches/gcc-8-branch/gcc/ChangeLog
    branches/gcc-8-branch/gcc/config/rs6000/rs6000-modes.def
    branches/gcc-8-branch/gcc/config/rs6000/rs6000.c
    branches/gcc-8-branch/gcc/config/rs6000/rs6000.h
    branches/gcc-8-branch/gcc/config/rs6000/rs6000.md
    branches/gcc-8-branch/libgcc/ChangeLog
    branches/gcc-8-branch/libgcc/config/rs6000/t-float128
    branches/gcc-8-branch/libgcc/config/rs6000/t-float128-hw