[PATCH,rs6000] PR80108: Fix ICE with cross compiler

[Kelvin Nilsen <kdnilsen at linux dot vnet dot ibm dot com>]

PR 80108 describes an ICE that occurs on an existing test program when
compiled with a particular combination of target options.  

This patch fixes the compiler to reject that particular combination of
target options since it is not meaningful and duplicates the offending
test case with a dg-options directive to exercise the problematic
command-line options.

This patch has been bootstrapped and tested with no regressions on both
powerpc64-unknown-linux-gnu and powerpc64le-unknown-linux-gnu.  Is
this ok for the trunk?


gcc/ChangeLog:

2017-03-31  Kelvin Nilsen  <kelvin@gcc.gnu.org>

	PR target/80108
	* config/rs6000/rs6000.c (rs6000_option_override_internal):
	Enhance special handling given to the TARGET_P9_MINMAX option in
	relation to certain other options.

gcc/testsuite/ChangeLog:

2017-03-31  Kelvin Nilsen  <kelvin@gcc.gnu.org>

	PR target/80108
	* gcc.target/powerpc/ppc-fortran/ppc-fortran.exp: New file.
	* gcc.target/powerpc/ppc-fortran/pr80108-1.f90: New test.

Index: gcc/config/rs6000/rs6000.c
===================================================================
--- gcc/config/rs6000/rs6000.c	(revision 246573)
+++ gcc/config/rs6000/rs6000.c	(working copy)
@@ -4273,8 +4273,30 @@ rs6000_option_override_internal (bool global_init_
   /* For the newer switches (vsx, dfp, etc.) set some of the older options,
      unless the user explicitly used the -mno-<option> to disable the code.  */
   if (TARGET_P9_VECTOR || TARGET_MODULO || TARGET_P9_DFORM_SCALAR
-      || TARGET_P9_DFORM_VECTOR || TARGET_P9_DFORM_BOTH > 0 || TARGET_P9_MINMAX)
+      || TARGET_P9_DFORM_VECTOR || TARGET_P9_DFORM_BOTH > 0)
     rs6000_isa_flags |= (ISA_3_0_MASKS_SERVER & ~rs6000_isa_flags_explicit);
+  else if (TARGET_P9_MINMAX)
+    {
+      if (have_cpu)
+	{
+	  if (cpu_index == PROCESSOR_POWER9)
+	    /* legacy behavior: allow -mcpu-power9 with certain capabilities
+	       (eg -mno-vsx) explicitly disabled.  */
+	    rs6000_isa_flags |=
+	      (ISA_3_0_MASKS_SERVER & ~rs6000_isa_flags_explicit);
+	  else
+	    error ("Power9 target option is incompatible with -mcpu=<xxx> for "
+		   "<xxx> less than power9");
+	}
+      else if ((ISA_3_0_MASKS_SERVER & rs6000_isa_flags_explicit)
+	       != (ISA_3_0_MASKS_SERVER & rs6000_isa_flags
+		   & rs6000_isa_flags_explicit))
+	/* Enforce that none of the ISA_3_0_MASKS_SERVER flags
+	   were explicitly cleared.  */
+	error ("-mpower9-minmax incompatible with explicitly disabled options");
+      else
+	rs6000_isa_flags |= ISA_3_0_MASKS_SERVER;
+    }
   else if (TARGET_P8_VECTOR || TARGET_DIRECT_MOVE || TARGET_CRYPTO)
     rs6000_isa_flags |= (ISA_2_7_MASKS_SERVER & ~rs6000_isa_flags_explicit);
   else if (TARGET_VSX)
Index: gcc/testsuite/gcc.target/powerpc/ppc-fortran/ppc-fortran.exp
===================================================================
--- gcc/testsuite/gcc.target/powerpc/ppc-fortran/ppc-fortran.exp	(revision 0)
+++ gcc/testsuite/gcc.target/powerpc/ppc-fortran/ppc-fortran.exp	(revision 246624)
@@ -0,0 +1,65 @@
+#   Copyright (C) 2004-2017 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GCC; see the file COPYING3.  If not see
+# <http://www.gnu.org/licenses/>.
+
+# GCC testsuite that uses the `dg.exp' driver.
+
+# Load support procs.
+load_lib gfortran-dg.exp
+
+# If a testcase doesn't have special options, use these.
+global DEFAULT_FFLAGS
+if ![info exists DEFAULT_FFLAGS] then {
+    set DEFAULT_FFLAGS " -pedantic-errors"
+}
+
+# Initialize `dg'.
+dg-init
+
+global gfortran_test_path
+global gfortran_aux_module_flags
+set gfortran_test_path $srcdir/$subdir
+set gfortran_aux_module_flags $DEFAULT_FFLAGS
+proc dg-compile-aux-modules { args } {
+    global gfortran_test_path
+    global gfortran_aux_module_flags
+    if { [llength $args] != 2 } {
+	error "dg-set-target-env-var: needs one argument"
+	return
+    }
+
+    set level [info level]
+    if { [info procs dg-save-unknown] != [list] } {
+	rename dg-save-unknown dg-save-unknown-level-$level
+    }
+
+    dg-test $gfortran_test_path/[lindex $args 1] "" $gfortran_aux_module_flags
+    # cleanup-modules is intentionally not invoked here.
+
+    if { [info procs dg-save-unknown-level-$level] != [list] } {
+	rename dg-save-unknown-level-$level dg-save-unknown
+    }
+}
+
+# Main loop.
+gfortran-dg-runtest [lsort \
+       [glob -nocomplain $srcdir/$subdir/*.\[fF\]{,90,95,03,08} ] ] "" $DEFAULT_FFLAGS
+
+gfortran-dg-runtest [lsort \
+       [glob -nocomplain $srcdir/$subdir/g77/*.\[fF\] ] ] "" $DEFAULT_FFLAGS
+
+
+# All done.
+dg-finish
Index: gcc/testsuite/gcc.target/powerpc/ppc-fortran/pr80108-1.f90
===================================================================
--- gcc/testsuite/gcc.target/powerpc/ppc-fortran/pr80108-1.f90	(revision 0)
+++ gcc/testsuite/gcc.target/powerpc/ppc-fortran/pr80108-1.f90	(working copy)
@@ -0,0 +1,53 @@
+! Originally contributed by Tobias Burnas.
+! { dg-do compile { target { powerpc*-*-* } } }
+! { dg-skip-if "do not override -mcpu" { powerpc*-*-* } { "-mcpu=*" } { "-mcpu=power9" } }
+! { dg-require-effective-target powerpc_p9vector_ok }
+! { dg-options "-m32 -mcpu=405 -mpower9-minmax -mfloat128-type" }
+! { dg-excess-errors "expect error due to conflicting target options" }
+! Since the error message is not associated with a particular line
+! number, we cannot use the dg-error directive and cannot specify a
+! regexp to describe the expected error message.  The expected error
+! message is:
+!  "Power9 target option is incompatible with -mcpu=<xxx> for <xxx>
+!    less than power9"
+
+program stream_test
+    implicit none
+    character(len=*), parameter :: rec1 = 'record1'
+    character(len=*), parameter :: rec2 = 'record2'
+    character(len=50) :: str1,str2
+    integer           :: len, i
+    real              :: r
+
+    open(10,form='formatted',access='stream',&
+         status='scratch',position='rewind')
+    write(10,'(a)') rec1//new_line('a')//rec2
+    rewind(10)
+    read(10,*) str1
+    read(10,*) str2
+    if(str1 /= rec1 .or. str2 /= rec2) call abort()
+    rewind(10)
+    read(10,'(a)') str1
+    read(10,'(a)') str2
+    if(str1 /= rec1 .or. str2 /= rec2) call abort()
+    close(10)
+
+    open(10,form='formatted',access='stream',&
+         status='scratch',position='rewind')
+    write(10,*) '123 '//trim(rec1)//'  1e-12'
+    write(10,*) '12345.6789'
+    rewind(10)
+    read(10,*) i,str1
+    read(10,*) r
+    if(i /= 123 .or. str1 /= rec1 .or. r /= 12345.6789) &
+      call abort()
+    close(10)
+
+    open(unit=10,form='unformatted',access='stream', &
+         status='scratch',position='rewind')
+    write(10) rec1//new_line('a')//rec2
+    len = len_trim(rec1//new_line('a')//rec2)
+    rewind(10)
+    read(10) str1(1:len)
+    if(str1 /= rec1//new_line('a')//rec2) call abort()
+end program stream_test