Create crtsavres.o for powerpc builds

Summary:
GCC expects to link in a crtsavres.o on powerpc platforms.  On
powerpc64 this is an empty file, but on powerpc and powerpcspe this does contain
some save/restore functions, which may not actually be necessary for newer
modern GCC and clang.  This appeases the in-tree gcc, though, and is needed in
order to switch to the BSD CRTRBEGIN.

PR:	233751
Reviewed By: andrew
Differential Revision: https://reviews.freebsd.org/D18826

gnu/lib/csu/Makefile

@@ -28,10 +28,6 @@ CRTS_CFLAGS=	-DCRTSTUFFS_O -DSHARED ${PICFLAG}
 CFLAGS+=	-DTARGET_ARM_EABI
 .endif
 
-.if ${MACHINE_CPUARCH} == "powerpc"
-TGTOBJS=	crtsavres.o
-SRCS+=		crtsavres.asm
-.endif
 .if ${MACHINE_CPUARCH} == "sparc64"
 TGTOBJS=	crtfastmath.o
 SRCS+=		crtfastmath.c

lib/csu/powerpc/Makefile

@@ -2,7 +2,7 @@
 
 .PATH: ${.CURDIR:H}/common
 
-SRCS=		crt1.c crti.S crtn.S
+SRCS=		crt1.c crti.S crtn.S crtsavres.S
 OBJS=		${SRCS:N*.h:R:S/$/.o/g}
 OBJS+=		Scrt1.o gcrt1.o
 CFLAGS+=	-I${.CURDIR:H}/common \

lib/csu/powerpc/crtsavres.S

@@ -0,0 +1,191 @@
+/*-
+ * SPDX-License-Identifier: BSD-1-Clause
+ *
+ * Copyright 2019 Justin Hibbits
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <machine/asm.h>
+__FBSDID("$FreeBSD$");
+
+.text
+
+/*
+ * The PowerPC ABI spec requires the following save/restore functions to be
+ * provided:
+ *
+ * _savefpr_N
+ * _restfpr_N
+ * _restfpr_N_x
+ * _savegpr_N
+ * _restgpr_N
+ * _restgpr_N_x
+ * 
+ * With N ranging from 14 to 31, to save the nonvolatile registers.
+ */
+
+#define _CRTENTRY(name) \
+	.text; \
+	.globl	name; \
+	.type	name,@function; \
+	name:
+
+#define SAVEFPR(r)	_CRTENTRY(__CONCAT(_savefpr_,r))	\
+	stfd	r,(-256 + r * 8)(11)
+
+SAVEFPR(14)
+SAVEFPR(15)
+SAVEFPR(16)
+SAVEFPR(17)
+SAVEFPR(18)
+SAVEFPR(19)
+SAVEFPR(20)
+SAVEFPR(21)
+SAVEFPR(22)
+SAVEFPR(23)
+SAVEFPR(24)
+SAVEFPR(25)
+SAVEFPR(26)
+SAVEFPR(27)
+SAVEFPR(28)
+SAVEFPR(29)
+SAVEFPR(30)
+SAVEFPR(31)
+	blr
+
+#define RESTFPR(r)	_CRTENTRY(__CONCAT(_restfpr_,r))	\
+	lfd	r,(-256 + r * 8)(11)
+
+RESTFPR(14)
+RESTFPR(15)
+RESTFPR(16)
+RESTFPR(17)
+RESTFPR(18)
+RESTFPR(19)
+RESTFPR(20)
+RESTFPR(21)
+RESTFPR(22)
+RESTFPR(23)
+RESTFPR(24)
+RESTFPR(25)
+RESTFPR(26)
+RESTFPR(27)
+RESTFPR(28)
+RESTFPR(29)
+RESTFPR(30)
+RESTFPR(31)
+	blr
+
+#define SAVEGPR(r)	_CRTENTRY(__CONCAT(_savegpr_,r))	\
+	stfd	r,(-128 + r*4)(11)
+
+SAVEGPR(14)
+SAVEGPR(15)
+SAVEGPR(16)
+SAVEGPR(17)
+SAVEGPR(18)
+SAVEGPR(19)
+SAVEGPR(20)
+SAVEGPR(21)
+SAVEGPR(22)
+SAVEGPR(23)
+SAVEGPR(24)
+SAVEGPR(25)
+SAVEGPR(26)
+SAVEGPR(27)
+SAVEGPR(28)
+SAVEGPR(29)
+SAVEGPR(30)
+SAVEGPR(31)
+	blr
+
+#define RESTGPR(r)	_CRTENTRY(__CONCAT(_restgpr_,r))	\
+	lwz	r,(-128 + r*4)(11)
+
+RESTGPR(14)
+RESTGPR(15)
+RESTGPR(16)
+RESTGPR(17)
+RESTGPR(18)
+RESTGPR(19)
+RESTGPR(20)
+RESTGPR(21)
+RESTGPR(22)
+RESTGPR(23)
+RESTGPR(24)
+RESTGPR(25)
+RESTGPR(26)
+RESTGPR(27)
+RESTGPR(28)
+RESTGPR(29)
+RESTGPR(30)
+RESTGPR(31)
+	blr
+
+#define RESTFPR_X(r)	_CRTENTRY(__CONCAT(__CONCAT(_restfpr_,r),_x))	\
+	lfd	r,(-256 + r * 8)(11)
+
+RESTFPR_X(14)
+RESTFPR_X(15)
+RESTFPR_X(16)
+RESTFPR_X(17)
+RESTFPR_X(18)
+RESTFPR_X(19)
+RESTFPR_X(20)
+RESTFPR_X(21)
+RESTFPR_X(22)
+RESTFPR_X(23)
+RESTFPR_X(24)
+RESTFPR_X(25)
+RESTFPR_X(26)
+RESTFPR_X(27)
+RESTFPR_X(28)
+RESTFPR_X(29)
+RESTFPR_X(30)
+RESTFPR_X(31)
+	lwz	0,4(11)
+	mtlr	0
+	mr	1,11
+	blr
+
+#define RESTGPR_X(r)	_CRTENTRY(__CONCAT(__CONCAT(_restgpr_,r),_x))	\
+	lwz	r,(-128 + r*4)(11)
+
+RESTGPR_X(14)
+RESTGPR_X(15)
+RESTGPR_X(16)
+RESTGPR_X(17)
+RESTGPR_X(18)
+RESTGPR_X(19)
+RESTGPR_X(20)
+RESTGPR_X(21)
+RESTGPR_X(22)
+RESTGPR_X(23)
+RESTGPR_X(24)
+RESTGPR_X(25)
+RESTGPR_X(26)
+RESTGPR_X(27)
+RESTGPR_X(28)
+RESTGPR_X(29)
+RESTGPR_X(30)
+RESTGPR_X(31)
+	lwz	0,4(11)
+	mtlr	0
+	mr	1,11
+	blr

lib/csu/powerpc64/Makefile

@@ -4,7 +4,7 @@
 
 SRCS=		crt1.c crti.S crtn.S
 OBJS=		${SRCS:N*.h:R:S/$/.o/g}
-OBJS+=		Scrt1.o gcrt1.o
+OBJS+=		crtsavres.o Scrt1.o gcrt1.o
 CFLAGS+=	-I${.CURDIR:H}/common \
 		-I${SRCTOP}/lib/libc/include \
 		-mlongcall -DCRT_IRELOC_SUPPRESS
@@ -18,7 +18,7 @@ FILESDIR=	${LIBDIR}
 .undef LIBRARIES_ONLY
 
 CLEANFILES=	${OBJS}
-CLEANFILES+=	crt1.s gcrt1.s Scrt1.s
+CLEANFILES+=	crt1.s crtsavres.s gcrt1.s Scrt1.s
 
 # See the comment in lib/csu/common/crtbrand.c for the reason crt1.c is not
 # directly compiled to .o files.
@@ -27,6 +27,10 @@ crt1.s: crt1.c
 	${CC} ${CFLAGS} -S -o ${.TARGET} ${.CURDIR}/crt1.c
 	sed ${SED_FIX_NOTE} ${.TARGET}
 
+# On powerpc64 crtsavres is an empty file
+crtsavres.s:
+	touch ${.TARGET}
+
 crt1.o: crt1.s
 	${CC} ${CFLAGS:N-g} ${ACFLAGS} -c -o ${.TARGET} crt1.s