[PATCH v3 03/10] GCN libgcc.

[Andrew Stubbs <ams at codesourcery dot com>]

[Already approved by Jeff Law.  Included here for completeness.]

This patch contains the GCN port of libgcc.

2018-12-12  Andrew Stubbs  <ams@codesourcery.com>
	    Kwok Cheung Yeung  <kcy@codesourcery.com>
	    Julian Brown  <julian@codesourcery.com>
	    Tom de Vries  <tom@codesourcery.com>

	libgcc/
	* config.host: Recognize amdgcn*-*-amdhsa.
	* config/gcn/crt0.c: New file.
	* config/gcn/lib2-divmod-hi.c: New file.
	* config/gcn/lib2-divmod.c: New file.
	* config/gcn/lib2-gcn.h: New file.
	* config/gcn/sfp-machine.h: New file.
	* config/gcn/t-amdgcn: New file.
---
 libgcc/config.host                 |   8 +++
 libgcc/config/gcn/crt0.c           |  23 ++++++++
 libgcc/config/gcn/lib2-divmod-hi.c | 117 +++++++++++++++++++++++++++++++++++++
 libgcc/config/gcn/lib2-divmod.c    | 117 +++++++++++++++++++++++++++++++++++++
 libgcc/config/gcn/lib2-gcn.h       |  49 ++++++++++++++++
 libgcc/config/gcn/sfp-machine.h    |  51 ++++++++++++++++
 libgcc/config/gcn/t-amdgcn         |  16 +++++
 7 files changed, 381 insertions(+)
 create mode 100644 libgcc/config/gcn/crt0.c
 create mode 100644 libgcc/config/gcn/lib2-divmod-hi.c
 create mode 100644 libgcc/config/gcn/lib2-divmod.c
 create mode 100644 libgcc/config/gcn/lib2-gcn.h
 create mode 100644 libgcc/config/gcn/sfp-machine.h
 create mode 100644 libgcc/config/gcn/t-amdgcn

diff --git a/libgcc/config.host b/libgcc/config.host
index 1cbc8ac..a854ede 100644
--- a/libgcc/config.host
+++ b/libgcc/config.host
@@ -91,6 +91,10 @@ alpha*-*-*)
 am33_2.0-*-linux*)
 	cpu_type=mn10300
 	;;
+amdgcn*-*-*)
+	cpu_type=gcn
+	tmake_file="${tmake_file} t-softfp-sfdf t-softfp"
+	;;
 arc*-*-*)
 	cpu_type=arc
 	;;
@@ -387,6 +391,10 @@ alpha*-dec-*vms*)
 	extra_parts="$extra_parts vms-dwarf2.o vms-dwarf2eh.o"
 	md_unwind_header=alpha/vms-unwind.h
 	;;
+amdgcn*-*-amdhsa)
+	tmake_file="$tmake_file gcn/t-amdgcn"
+	extra_parts="crt0.o"
+	;;
 arc*-*-elf*)
 	tmake_file="arc/t-arc"
 	extra_parts="crti.o crtn.o crtend.o crtbegin.o crtendS.o crtbeginS.o"
diff --git a/libgcc/config/gcn/crt0.c b/libgcc/config/gcn/crt0.c
new file mode 100644
index 0000000..00a3f42
--- /dev/null
+++ b/libgcc/config/gcn/crt0.c
@@ -0,0 +1,23 @@
+/* Copyright (C) 2017-2018 Free Software Foundation, Inc.
+
+   This file 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.
+
+   This file 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/>.  */
+
+/* Provide an entry point symbol to silence a linker warning.  */
+void _start() {}
diff --git a/libgcc/config/gcn/lib2-divmod-hi.c b/libgcc/config/gcn/lib2-divmod-hi.c
new file mode 100644
index 0000000..90626f6
--- /dev/null
+++ b/libgcc/config/gcn/lib2-divmod-hi.c
@@ -0,0 +1,117 @@
+/* Copyright (C) 2012-2018 Free Software Foundation, Inc.
+   Contributed by Altera and Mentor Graphics, Inc.
+
+This file 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.
+
+This file 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 "lib2-gcn.h"
+
+/* 16-bit HI divide and modulo as used in gcn.  */
+
+static UHItype
+udivmodhi4 (UHItype num, UHItype den, word_type modwanted)
+{
+  UHItype bit = 1;
+  UHItype res = 0;
+
+  while (den < num && bit && !(den & (1L<<15)))
+    {
+      den <<=1;
+      bit <<=1;
+    }
+  while (bit)
+    {
+      if (num >= den)
+	{
+	  num -= den;
+	  res |= bit;
+	}
+      bit >>=1;
+      den >>=1;
+    }
+  if (modwanted)
+    return num;
+  return res;
+}
+
+
+HItype
+__divhi3 (HItype a, HItype b)
+{
+  word_type neg = 0;
+  HItype res;
+
+  if (a < 0)
+    {
+      a = -a;
+      neg = !neg;
+    }
+
+  if (b < 0)
+    {
+      b = -b;
+      neg = !neg;
+    }
+
+  res = udivmodhi4 (a, b, 0);
+
+  if (neg)
+    res = -res;
+
+  return res;
+}
+
+
+HItype
+__modhi3 (HItype a, HItype b)
+{
+  word_type neg = 0;
+  HItype res;
+
+  if (a < 0)
+    {
+      a = -a;
+      neg = 1;
+    }
+
+  if (b < 0)
+    b = -b;
+
+  res = udivmodhi4 (a, b, 1);
+
+  if (neg)
+    res = -res;
+
+  return res;
+}
+
+
+UHItype
+__udivhi3 (UHItype a, UHItype b)
+{
+  return udivmodhi4 (a, b, 0);
+}
+
+
+UHItype
+__umodhi3 (UHItype a, UHItype b)
+{
+  return udivmodhi4 (a, b, 1);
+}
+
diff --git a/libgcc/config/gcn/lib2-divmod.c b/libgcc/config/gcn/lib2-divmod.c
new file mode 100644
index 0000000..d38a7a0
--- /dev/null
+++ b/libgcc/config/gcn/lib2-divmod.c
@@ -0,0 +1,117 @@
+/* Copyright (C) 2012-2018 Free Software Foundation, Inc.
+   Contributed by Altera and Mentor Graphics, Inc.
+
+This file 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.
+
+This file 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 "lib2-gcn.h"
+
+/* 32-bit SI divide and modulo as used in gcn.  */
+
+static USItype
+udivmodsi4 (USItype num, USItype den, word_type modwanted)
+{
+  USItype bit = 1;
+  USItype res = 0;
+
+  while (den < num && bit && !(den & (1L<<31)))
+    {
+      den <<=1;
+      bit <<=1;
+    }
+  while (bit)
+    {
+      if (num >= den)
+	{
+	  num -= den;
+	  res |= bit;
+	}
+      bit >>=1;
+      den >>=1;
+    }
+  if (modwanted)
+    return num;
+  return res;
+}
+
+
+SItype
+__divsi3 (SItype a, SItype b)
+{
+  word_type neg = 0;
+  SItype res;
+
+  if (a < 0)
+    {
+      a = -a;
+      neg = !neg;
+    }
+
+  if (b < 0)
+    {
+      b = -b;
+      neg = !neg;
+    }
+
+  res = udivmodsi4 (a, b, 0);
+
+  if (neg)
+    res = -res;
+
+  return res;
+}
+
+
+SItype
+__modsi3 (SItype a, SItype b)
+{
+  word_type neg = 0;
+  SItype res;
+
+  if (a < 0)
+    {
+      a = -a;
+      neg = 1;
+    }
+
+  if (b < 0)
+    b = -b;
+
+  res = udivmodsi4 (a, b, 1);
+
+  if (neg)
+    res = -res;
+
+  return res;
+}
+
+
+SItype
+__udivsi3 (SItype a, SItype b)
+{
+  return udivmodsi4 (a, b, 0);
+}
+
+
+SItype
+__umodsi3 (SItype a, SItype b)
+{
+  return udivmodsi4 (a, b, 1);
+}
+
diff --git a/libgcc/config/gcn/lib2-gcn.h b/libgcc/config/gcn/lib2-gcn.h
new file mode 100644
index 0000000..ceada82
--- /dev/null
+++ b/libgcc/config/gcn/lib2-gcn.h
@@ -0,0 +1,49 @@
+/* Integer arithmetic support for gcn.
+
+   Copyright (C) 2012-2018 Free Software Foundation, Inc.
+   Contributed by Altera and Mentor Graphics, Inc.
+
+   This file 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.
+
+   This file 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/>.  */
+
+#ifndef LIB2_GCN_H
+#define LIB2_GCN_H
+
+/* Types.  */
+
+typedef char QItype __attribute__ ((mode (QI)));
+typedef unsigned char UQItype __attribute__ ((mode (QI)));
+typedef short HItype __attribute__ ((mode (HI)));
+typedef unsigned short UHItype __attribute__ ((mode (HI)));
+typedef int SItype __attribute__ ((mode (SI)));
+typedef unsigned int USItype __attribute__ ((mode (SI)));
+typedef int word_type __attribute__ ((mode (__word__)));
+
+/* Exported functions.  */
+extern SItype __divsi3 (SItype, SItype);
+extern SItype __modsi3 (SItype, SItype);
+extern SItype __udivsi3 (SItype, SItype);
+extern SItype __umodsi3 (SItype, SItype);
+extern HItype __divhi3 (HItype, HItype);
+extern HItype __modhi3 (HItype, HItype);
+extern UHItype __udivhi3 (UHItype, UHItype);
+extern UHItype __umodhi3 (UHItype, UHItype);
+extern SItype __mulsi3 (SItype, SItype);
+
+#endif /* LIB2_GCN_H */
diff --git a/libgcc/config/gcn/sfp-machine.h b/libgcc/config/gcn/sfp-machine.h
new file mode 100644
index 0000000..7874081
--- /dev/null
+++ b/libgcc/config/gcn/sfp-machine.h
@@ -0,0 +1,51 @@
+/* Use 32-bit types here to prevent longlong.h trying to use TImode.
+   Once TImode works we might be better to use 64-bit here.  */
+
+#define _FP_W_TYPE_SIZE		32
+#define _FP_W_TYPE		unsigned int
+#define _FP_WS_TYPE		signed int
+#define _FP_I_TYPE		int
+
+#define _FP_MUL_MEAT_S(R,X,Y)				\
+  _FP_MUL_MEAT_1_wide(_FP_WFRACBITS_S,R,X,Y,umul_ppmm)
+#define _FP_MUL_MEAT_D(R,X,Y)				\
+  _FP_MUL_MEAT_2_wide(_FP_WFRACBITS_D,R,X,Y,umul_ppmm)
+
+#define _FP_DIV_MEAT_S(R,X,Y)	_FP_DIV_MEAT_1_loop(S,R,X,Y)
+#define _FP_DIV_MEAT_D(R,X,Y)	_FP_DIV_MEAT_2_udiv(D,R,X,Y)
+
+#define _FP_NANFRAC_S		((_FP_QNANBIT_S << 1) - 1)
+#define _FP_NANFRAC_D		((_FP_QNANBIT_D << 1) - 1), -1
+#define _FP_NANSIGN_S		0
+#define _FP_NANSIGN_D		0
+
+#define _FP_KEEPNANFRACP 1
+#define _FP_QNANNEGATEDP 0
+
+/* Someone please check this.  */
+#define _FP_CHOOSENAN(fs, wc, R, X, Y, OP)			\
+  do {								\
+    if ((_FP_FRAC_HIGH_RAW_##fs(X) & _FP_QNANBIT_##fs)		\
+	&& !(_FP_FRAC_HIGH_RAW_##fs(Y) & _FP_QNANBIT_##fs))	\
+      {								\
+	R##_s = Y##_s;						\
+	_FP_FRAC_COPY_##wc(R,Y);				\
+      }								\
+    else							\
+      {								\
+	R##_s = X##_s;						\
+	_FP_FRAC_COPY_##wc(R,X);				\
+      }								\
+    R##_c = FP_CLS_NAN;						\
+  } while (0)
+
+#define _FP_TININESS_AFTER_ROUNDING 0
+
+#define __LITTLE_ENDIAN 1234
+#define	__BIG_ENDIAN	4321
+#define __BYTE_ORDER __LITTLE_ENDIAN
+
+/* Define ALIASNAME as a strong alias for NAME.  */
+# define strong_alias(name, aliasname) _strong_alias(name, aliasname)
+# define _strong_alias(name, aliasname) \
+  extern __typeof (name) aliasname __attribute__ ((alias (#name)));
diff --git a/libgcc/config/gcn/t-amdgcn b/libgcc/config/gcn/t-amdgcn
new file mode 100644
index 0000000..8687c9f
--- /dev/null
+++ b/libgcc/config/gcn/t-amdgcn
@@ -0,0 +1,16 @@
+LIB2ADD += $(srcdir)/config/gcn/lib2-divmod.c \
+	   $(srcdir)/config/gcn/lib2-divmod-hi.c
+
+LIB2ADDEH=
+LIB2FUNCS_EXCLUDE=__main
+
+override LIB2FUNCS_ST := $(filter-out __gcc_bcmp,$(LIB2FUNCS_ST))
+
+# Debug information is not useful, and probably uses broken relocations
+LIBGCC2_DEBUG_CFLAGS = -g0
+
+crt0.o: $(srcdir)/config/gcn/crt0.c
+	$(crt_compile) -c $<
+
+# Prevent building "advanced" stuff (for example, gcov support).
+INHIBIT_LIBC_CFLAGS = -Dinhibit_libc