re PR target/85456 (PowerPC: Using -mabi=ieeelongdouble calls wrong function for __builtin_powi.)

[libgcc]
2018-04-20  Michael Meissner  <meissner@linux.ibm.com>

	PR target/85456
	* config/rs6000/_powikf2.c: New file.  Add support for the
	__builtin_powil function when long double is IEEE 128-bit floating
	point.
	* config/rs6000/float128-ifunc.c (__powikf2_resolve): Add
	__powikf2 support.
	(__powikf2): Likewise.
	* config/rs6000/quad-float128.h (__powikf2_sw): Likewise.
	(__powikf2_hw): Likewise.
	(__powikf2): Likewise.
	* config/rs6000/t-float128 (fp128_ppc_funcs): Likewise.
	* config/rs6000/t-float128-hw (fp128_hw_func): Likewise.
	(_powikf2-hw.c): Likewise.

[gcc]
2018-04-20  Michael Meissner  <meissner@linux.ibm.com>

	PR target/85456
	* config/rs6000/rs6000.c (init_float128_ieee): Add support to call
	__powikf2 when long double is IEEE 128-bit.

[gcc/testsuite]
2018-04-20  Michael Meissner  <meissner@linux.ibm.com>

	PR target/85456
	* gcc.target/powerpc/pr85456.c: New test.

From-SVN: r259533

6 files changed, 98 insertions, 3 deletions

diff --git a/libgcc/ChangeLog b/libgcc/ChangeLog
index 8a645c8..f0361dc 100644
--- a/libgcc/ChangeLog
+++ b/libgcc/ChangeLog
@@ -1,3 +1,19 @@
+2018-04-20  Michael Meissner  <meissner@linux.ibm.com>
+
+	PR target/85456
+	* config/rs6000/_powikf2.c: New file.  Add support for the
+	__builtin_powil function when long double is IEEE 128-bit floating
+	point.
+	* config/rs6000/float128-ifunc.c (__powikf2_resolve): Add
+	__powikf2 support.
+	(__powikf2): Likewise.
+	* config/rs6000/quad-float128.h (__powikf2_sw): Likewise.
+	(__powikf2_hw): Likewise.
+	(__powikf2): Likewise.
+	* config/rs6000/t-float128 (fp128_ppc_funcs): Likewise.
+	* config/rs6000/t-float128-hw (fp128_hw_func): Likewise.
+	(_powikf2-hw.c): Likewise.
+
 2018-04-19  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR libgcc/85334
diff --git a/libgcc/config/rs6000/_powikf2.c b/libgcc/config/rs6000/_powikf2.c
new file mode 100644
index 0000000..7afd096
--- /dev/null
+++ b/libgcc/config/rs6000/_powikf2.c
@@ -0,0 +1,63 @@
+/* Copyright (C) 1989-2018 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC 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, or (at your option) any later
+version.
+
+GCC 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.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+#include "soft-fp.h"
+#include "quad-float128.h"
+
+/* __powikf3 can be compiled 3 different ways:
+
+   1) If the assembler does not have support for the IEEE 128-bit insns
+   (xsaddqp, etc.) it is just compiled as __powikf2.
+
+   2) If the assembler has IEEE 128-bit floating point support, and __powikf2
+   is not previously defined, it is defined as __powikf2_sw.
+
+   3) If the assembler has IEEE 128-bit floating point support, and __powikf2
+   is included by _powikf2-hw.c, which defines __powikf2 as __powikf2_hw.  The
+   __powikf2_hw.c is compiled with -mcpu=power9 and it automatically uses the
+   IEEE 128-bit instructions.
+
+   For #2/#3, float128-ifunc.c defines an ifunc function for __powikf2, that
+   will use the software version on power7/power8 systems, and the hardware
+   version on power9 systems.
+
+   The code is cloned from the code in libgcc2.c (which handles the standard
+   SF, DF, TF, and XF types).  */
+
+#if defined(FLOAT128_HW_INSNS) && !defined(__powikf2)
+#define __powikf2 __powikf2_sw
+#endif
+
+TFtype
+__powikf2 (TFtype x, SItype_ppc m)
+{
+  unsigned int n = m < 0 ? -m : m;
+  TFtype y = n % 2 ? x : 1;
+  while (n >>= 1)
+    {
+      x = x * x;
+      if (n % 2)
+	y = y * x;
+    }
+  return m < 0 ? 1/y : y;
+}
diff --git a/libgcc/config/rs6000/float128-ifunc.c b/libgcc/config/rs6000/float128-ifunc.c
index 13a6045..8fcac24 100644
--- a/libgcc/config/rs6000/float128-ifunc.c
+++ b/libgcc/config/rs6000/float128-ifunc.c
@@ -84,6 +84,12 @@ __negkf2_resolve (void)
   return SW_OR_HW (__negkf2_sw, __negkf2_hw);
 }
 
+static __typeof__ (__powikf2_sw) *
+__powikf2_resolve (void)
+{
+  return SW_OR_HW (__powikf2_sw, __powikf2_hw);
+}
+
 static __typeof__ (__floatsikf_sw) *
 __floatsikf_resolve (void)
 {
@@ -243,6 +249,9 @@ TFtype __divkf3 (TFtype, TFtype)
 TFtype __negkf2 (TFtype)
   __attribute__ ((__ifunc__ ("__negkf2_resolve")));
 
+TFtype __powikf2 (TFtype, SItype_ppc)
+  __attribute__ ((__ifunc__ ("__powikf2_resolve")));
+
 CMPtype __eqkf2 (TFtype, TFtype)
   __attribute__ ((__ifunc__ ("__eqkf2_resolve")));
 
diff --git a/libgcc/config/rs6000/quad-float128.h b/libgcc/config/rs6000/quad-float128.h
index e10b25f..1d4d513 100644
--- a/libgcc/config/rs6000/quad-float128.h
+++ b/libgcc/config/rs6000/quad-float128.h
@@ -72,6 +72,7 @@ extern TFtype __subkf3_sw (TFtype, TFtype);
 extern TFtype __mulkf3_sw (TFtype, TFtype);
 extern TFtype __divkf3_sw (TFtype, TFtype);
 extern TFtype __negkf2_sw (TFtype);
+extern TFtype __powikf2_sw (TFtype, SItype_ppc);
 extern CMPtype __eqkf2_sw (TFtype, TFtype);
 extern CMPtype __gekf2_sw (TFtype, TFtype);
 extern CMPtype __lekf2_sw (TFtype, TFtype);
@@ -114,6 +115,7 @@ extern TFtype __subkf3_hw (TFtype, TFtype);
 extern TFtype __mulkf3_hw (TFtype, TFtype);
 extern TFtype __divkf3_hw (TFtype, TFtype);
 extern TFtype __negkf2_hw (TFtype);
+extern TFtype __powikf2_hw (TFtype, SItype_ppc);
 extern CMPtype __eqkf2_hw (TFtype, TFtype);
 extern CMPtype __gekf2_hw (TFtype, TFtype);
 extern CMPtype __lekf2_hw (TFtype, TFtype);
@@ -142,6 +144,7 @@ extern TFtype __subkf3 (TFtype, TFtype);
 extern TFtype __mulkf3 (TFtype, TFtype);
 extern TFtype __divkf3 (TFtype, TFtype);
 extern TFtype __negkf2 (TFtype);
+extern TFtype __powikf2 (TFtype, SItype_ppc);
 extern CMPtype __eqkf2 (TFtype, TFtype);
 extern CMPtype __nekf2 (TFtype, TFtype);
 extern CMPtype __gekf2 (TFtype, TFtype);
diff --git a/libgcc/config/rs6000/t-float128 b/libgcc/config/rs6000/t-float128
index 41ad527..8d52521 100644
--- a/libgcc/config/rs6000/t-float128
+++ b/libgcc/config/rs6000/t-float128
@@ -25,7 +25,7 @@ fp128_softfp_obj	= $(fp128_softfp_static_obj) $(fp128_softfp_shared_obj)
 # New functions for software emulation
 fp128_ppc_funcs		= floattikf floatuntikf fixkfti fixunskfti \
 			  extendkftf2-sw trunctfkf2-sw \
-			  sfp-exceptions _mulkc3 _divkc3
+			  sfp-exceptions _mulkc3 _divkc3 _powikf2
 
 fp128_ppc_src		= $(addprefix $(srcdir)/config/rs6000/,$(addsuffix \
 				.c,$(fp128_ppc_funcs)))
diff --git a/libgcc/config/rs6000/t-float128-hw b/libgcc/config/rs6000/t-float128-hw
index 7ab1069..acdddb0 100644
--- a/libgcc/config/rs6000/t-float128-hw
+++ b/libgcc/config/rs6000/t-float128-hw
@@ -6,9 +6,9 @@ FLOAT128_HW_INSNS	= -DFLOAT128_HW_INSNS
 
 # New functions for hardware support
 fp128_hardfp_src	= _mulkc3-hw.c _divkc3-hw.c
-fp128_hw_funcs		= float128-hw _mulkc3-hw _divkc3-hw
+fp128_hw_funcs		= float128-hw _mulkc3-hw _divkc3-hw _powikf2-hw
 fp128_hw_src		= $(srcdir)/config/rs6000/float128-hw.c _mulkc3-hw.c \
-			  _divkc3-hw.c
+			  _divkc3-hw.c _powikf2-hw.c
 fp128_hw_static_obj	= $(addsuffix $(objext),$(fp128_hw_funcs))
 fp128_hw_shared_obj	= $(addsuffix _s$(objext),$(fp128_hw_funcs))
 fp128_hw_obj		= $(fp128_hw_static_obj) $(fp128_hw_shared_obj)
@@ -43,3 +43,7 @@ _mulkc3-hw.c: $(srcdir)/config/rs6000/_mulkc3.c
 _divkc3-hw.c: $(srcdir)/config/rs6000/_divkc3.c
 	(echo "#define __divkc3 __divkc3_hw"; \
 	 cat $(srcdir)/config/rs6000/_divkc3.c) > _divkc3-hw.c
+
+_powikf2-hw.c: $(srcdir)/config/rs6000/_powikf2.c
+	(echo "#define __powikf2 __powikf2_hw"; \
+	 cat $(srcdir)/config/rs6000/_powikf2.c) > _powikf2-hw.c