diff --git a/CHANGES b/CHANGES
index a1c7d279df..e4a4675bcf 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,6 @@
+2133.	[port]		powerpc:  Support both IBM and MacOS Power PC
+			assembler syntaxes. [RT #16647]
+
 2132.	[bug]		Missing unlock on out of memory in
 			dns_dispatchmgr_setudp().
 
diff --git a/configure b/configure
index 51a7f42527..1d637a81af 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# Copyright (C) 2004-2006  Internet Systems Consortium, Inc. ("ISC")
+# Copyright (C) 2004-2007  Internet Systems Consortium, Inc. ("ISC")
 # Copyright (C) 1996-2003  Internet Software Consortium.
 #
 # Permission to use, copy, modify, and distribute this software for any
@@ -14,7 +14,7 @@
 # OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 # PERFORMANCE OF THIS SOFTWARE.
 #
-# $Id: configure,v 1.339.18.64 2007/01/08 01:58:16 marka Exp $
+# $Id: configure,v 1.339.18.65 2007/02/12 00:54:52 marka Exp $
 #
 # Portions Copyright (C) 1996-2001  Nominum, Inc.
 #
@@ -495,7 +495,7 @@ ac_includes_default="\
 # include <unistd.h>
 #endif"
 
-ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS subdirs build build_cpu build_vendor build_os host host_cpu host_vendor host_os SET_MAKE RANLIB ac_ct_RANLIB INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA LN_S STD_CINCLUDES STD_CDEFINES STD_CWARNINGS CCOPT AR ARFLAGS LN ETAGS PERL CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC EXEEXT OBJEXT CPP EGREP ISC_SOCKADDR_LEN_T ISC_PLATFORM_HAVELONGLONG ISC_PLATFORM_HAVELIFCONF ISC_PLATFORM_NEEDSYSSELECTH LWRES_PLATFORM_NEEDSYSSELECTH USE_OPENSSL DST_OPENSSL_INC USE_GSSAPI DST_GSSAPI_INC DNS_CRYPTO_LIBS ALWAYS_DEFINES ISC_PLATFORM_USETHREADS ISC_THREAD_DIR MKDEPCC MKDEPCFLAGS MKDEPPROG IRIX_DNSSEC_WARNINGS_HACK purify_path PURIFY ECHO ac_ct_AR STRIP ac_ct_STRIP CXX CXXFLAGS ac_ct_CXX CXXCPP F77 FFLAGS ac_ct_F77 LIBTOOL O A SA LIBTOOL_MKDEP_SED LIBTOOL_MODE_COMPILE LIBTOOL_MODE_INSTALL LIBTOOL_MODE_LINK LIBTOOL_ALLOW_UNDEFINED LIBTOOL_IN_MAIN LIBBIND ISC_PLATFORM_HAVEIPV6 LWRES_PLATFORM_HAVEIPV6 ISC_PLATFORM_NEEDNETINETIN6H LWRES_PLATFORM_NEEDNETINETIN6H ISC_PLATFORM_NEEDNETINET6IN6H LWRES_PLATFORM_NEEDNETINET6IN6H ISC_PLATFORM_HAVEINADDR6 LWRES_PLATFORM_HAVEINADDR6 ISC_PLATFORM_NEEDIN6ADDRANY LWRES_PLATFORM_NEEDIN6ADDRANY ISC_PLATFORM_NEEDIN6ADDRLOOPBACK LWRES_PLATFORM_NEEDIN6ADDRLOOPBACK ISC_PLATFORM_HAVEIN6PKTINFO ISC_PLATFORM_FIXIN6ISADDR ISC_IPV6_H ISC_IPV6_O ISC_ISCIPV6_O ISC_IPV6_C LWRES_HAVE_SIN6_SCOPE_ID ISC_PLATFORM_HAVESCOPEID ISC_PLATFORM_HAVEIF_LADDRREQ ISC_PLATFORM_HAVEIF_LADDRCONF ISC_PLATFORM_NEEDNTOP ISC_PLATFORM_NEEDPTON ISC_PLATFORM_NEEDATON ISC_PLATFORM_HAVESALEN LWRES_PLATFORM_HAVESALEN ISC_PLATFORM_MSGHDRFLAVOR ISC_PLATFORM_NEEDPORTT ISC_LWRES_NEEDADDRINFO ISC_LWRES_NEEDRRSETINFO ISC_LWRES_SETHOSTENTINT ISC_LWRES_ENDHOSTENTINT ISC_LWRES_GETNETBYADDRINADDR ISC_LWRES_SETNETENTINT ISC_LWRES_ENDNETENTINT ISC_LWRES_GETHOSTBYADDRVOID ISC_LWRES_NEEDHERRNO ISC_LWRES_GETIPNODEPROTO ISC_LWRES_GETADDRINFOPROTO ISC_LWRES_GETNAMEINFOPROTO ISC_PLATFORM_NEEDSTRSEP ISC_PLATFORM_NEEDMEMMOVE ISC_PLATFORM_NEEDSTRTOUL LWRES_PLATFORM_NEEDSTRTOUL GENRANDOMLIB ISC_PLATFORM_NEEDSTRLCPY ISC_PLATFORM_NEEDSTRLCAT ISC_PLATFORM_NEEDSPRINTF LWRES_PLATFORM_NEEDSPRINTF ISC_PLATFORM_NEEDVSNPRINTF LWRES_PLATFORM_NEEDVSNPRINTF ISC_EXTRA_OBJS ISC_EXTRA_SRCS ISC_PLATFORM_QUADFORMAT LWRES_PLATFORM_QUADFORMAT ISC_PLATFORM_HAVESYSUNH ISC_PLATFORM_RLIMITTYPE ISC_PLATFORM_USEDECLSPEC LWRES_PLATFORM_USEDECLSPEC ISC_PLATFORM_BRACEPTHREADONCEINIT ISC_PLATFORM_HAVEIFNAMETOINDEX ISC_PLATFORM_HAVEXADD ISC_PLATFORM_HAVECMPXCHG ISC_PLATFORM_HAVEATOMICSTORE ISC_PLATFORM_USEGCCASM ISC_PLATFORM_USEOSFASM ISC_PLATFORM_USESTDASM ISC_ARCH_DIR LATEX PDFLATEX W3M XSLTPROC XMLLINT XSLT_DOCBOOK_STYLE_HTML XSLT_DOCBOOK_STYLE_XHTML XSLT_DOCBOOK_STYLE_MAN XSLT_DOCBOOK_CHUNK_HTML XSLT_DOCBOOK_CHUNK_XHTML XSLT_DOCBOOK_CHUNKTOC_HTML XSLT_DOCBOOK_CHUNKTOC_XHTML XSLT_DOCBOOK_MAKETOC_HTML XSLT_DOCBOOK_MAKETOC_XHTML XSLT_DB2LATEX_STYLE XSLT_DB2LATEX_ADMONITIONS IDNLIBS BIND9_TOP_BUILDDIR BIND9_ISC_BUILDINCLUDE BIND9_ISCCC_BUILDINCLUDE BIND9_ISCCFG_BUILDINCLUDE BIND9_DNS_BUILDINCLUDE BIND9_LWRES_BUILDINCLUDE BIND9_BIND9_BUILDINCLUDE BIND9_VERSION PG_CONFIG USE_DLZ DLZ_DRIVER_INCLUDES DLZ_DRIVER_LIBS DLZ_DRIVER_SRCS DLZ_DRIVER_OBJS BUILD_CC BUILD_CFLAGS BUILD_CPPFLAGS BUILD_LDFLAGS BUILD_LIBS LIBOBJS LTLIBOBJS'
+ac_subst_vars='SHELL PATH_SEPARATOR PACKAGE_NAME PACKAGE_TARNAME PACKAGE_VERSION PACKAGE_STRING PACKAGE_BUGREPORT exec_prefix prefix program_transform_name bindir sbindir libexecdir datadir sysconfdir sharedstatedir localstatedir libdir includedir oldincludedir infodir mandir build_alias host_alias target_alias DEFS ECHO_C ECHO_N ECHO_T LIBS subdirs build build_cpu build_vendor build_os host host_cpu host_vendor host_os SET_MAKE RANLIB ac_ct_RANLIB INSTALL_PROGRAM INSTALL_SCRIPT INSTALL_DATA LN_S STD_CINCLUDES STD_CDEFINES STD_CWARNINGS CCOPT AR ARFLAGS LN ETAGS PERL CC CFLAGS LDFLAGS CPPFLAGS ac_ct_CC EXEEXT OBJEXT CPP EGREP ISC_SOCKADDR_LEN_T ISC_PLATFORM_HAVELONGLONG ISC_PLATFORM_HAVELIFCONF ISC_PLATFORM_NEEDSYSSELECTH LWRES_PLATFORM_NEEDSYSSELECTH USE_OPENSSL DST_OPENSSL_INC USE_GSSAPI DST_GSSAPI_INC DNS_CRYPTO_LIBS ALWAYS_DEFINES ISC_PLATFORM_USETHREADS ISC_THREAD_DIR MKDEPCC MKDEPCFLAGS MKDEPPROG IRIX_DNSSEC_WARNINGS_HACK purify_path PURIFY ECHO ac_ct_AR STRIP ac_ct_STRIP CXX CXXFLAGS ac_ct_CXX CXXCPP F77 FFLAGS ac_ct_F77 LIBTOOL O A SA LIBTOOL_MKDEP_SED LIBTOOL_MODE_COMPILE LIBTOOL_MODE_INSTALL LIBTOOL_MODE_LINK LIBTOOL_ALLOW_UNDEFINED LIBTOOL_IN_MAIN LIBBIND ISC_PLATFORM_HAVEIPV6 LWRES_PLATFORM_HAVEIPV6 ISC_PLATFORM_NEEDNETINETIN6H LWRES_PLATFORM_NEEDNETINETIN6H ISC_PLATFORM_NEEDNETINET6IN6H LWRES_PLATFORM_NEEDNETINET6IN6H ISC_PLATFORM_HAVEINADDR6 LWRES_PLATFORM_HAVEINADDR6 ISC_PLATFORM_NEEDIN6ADDRANY LWRES_PLATFORM_NEEDIN6ADDRANY ISC_PLATFORM_NEEDIN6ADDRLOOPBACK LWRES_PLATFORM_NEEDIN6ADDRLOOPBACK ISC_PLATFORM_HAVEIN6PKTINFO ISC_PLATFORM_FIXIN6ISADDR ISC_IPV6_H ISC_IPV6_O ISC_ISCIPV6_O ISC_IPV6_C LWRES_HAVE_SIN6_SCOPE_ID ISC_PLATFORM_HAVESCOPEID ISC_PLATFORM_HAVEIF_LADDRREQ ISC_PLATFORM_HAVEIF_LADDRCONF ISC_PLATFORM_NEEDNTOP ISC_PLATFORM_NEEDPTON ISC_PLATFORM_NEEDATON ISC_PLATFORM_HAVESALEN LWRES_PLATFORM_HAVESALEN ISC_PLATFORM_MSGHDRFLAVOR ISC_PLATFORM_NEEDPORTT ISC_LWRES_NEEDADDRINFO ISC_LWRES_NEEDRRSETINFO ISC_LWRES_SETHOSTENTINT ISC_LWRES_ENDHOSTENTINT ISC_LWRES_GETNETBYADDRINADDR ISC_LWRES_SETNETENTINT ISC_LWRES_ENDNETENTINT ISC_LWRES_GETHOSTBYADDRVOID ISC_LWRES_NEEDHERRNO ISC_LWRES_GETIPNODEPROTO ISC_LWRES_GETADDRINFOPROTO ISC_LWRES_GETNAMEINFOPROTO ISC_PLATFORM_NEEDSTRSEP ISC_PLATFORM_NEEDMEMMOVE ISC_PLATFORM_NEEDSTRTOUL LWRES_PLATFORM_NEEDSTRTOUL GENRANDOMLIB ISC_PLATFORM_NEEDSTRLCPY ISC_PLATFORM_NEEDSTRLCAT ISC_PLATFORM_NEEDSPRINTF LWRES_PLATFORM_NEEDSPRINTF ISC_PLATFORM_NEEDVSNPRINTF LWRES_PLATFORM_NEEDVSNPRINTF ISC_EXTRA_OBJS ISC_EXTRA_SRCS ISC_PLATFORM_QUADFORMAT LWRES_PLATFORM_QUADFORMAT ISC_PLATFORM_HAVESYSUNH ISC_PLATFORM_RLIMITTYPE ISC_PLATFORM_USEDECLSPEC LWRES_PLATFORM_USEDECLSPEC ISC_PLATFORM_BRACEPTHREADONCEINIT ISC_PLATFORM_HAVEIFNAMETOINDEX ISC_PLATFORM_HAVEXADD ISC_PLATFORM_HAVECMPXCHG ISC_PLATFORM_HAVEATOMICSTORE ISC_PLATFORM_USEGCCASM ISC_PLATFORM_USEOSFASM ISC_PLATFORM_USESTDASM ISC_PLATFORM_USEMACASM ISC_ARCH_DIR LATEX PDFLATEX W3M XSLTPROC XMLLINT XSLT_DOCBOOK_STYLE_HTML XSLT_DOCBOOK_STYLE_XHTML XSLT_DOCBOOK_STYLE_MAN XSLT_DOCBOOK_CHUNK_HTML XSLT_DOCBOOK_CHUNK_XHTML XSLT_DOCBOOK_CHUNKTOC_HTML XSLT_DOCBOOK_CHUNKTOC_XHTML XSLT_DOCBOOK_MAKETOC_HTML XSLT_DOCBOOK_MAKETOC_XHTML XSLT_DB2LATEX_STYLE XSLT_DB2LATEX_ADMONITIONS IDNLIBS BIND9_TOP_BUILDDIR BIND9_ISC_BUILDINCLUDE BIND9_ISCCC_BUILDINCLUDE BIND9_ISCCFG_BUILDINCLUDE BIND9_DNS_BUILDINCLUDE BIND9_LWRES_BUILDINCLUDE BIND9_BIND9_BUILDINCLUDE BIND9_VERSION PG_CONFIG USE_DLZ DLZ_DRIVER_INCLUDES DLZ_DRIVER_LIBS DLZ_DRIVER_SRCS DLZ_DRIVER_OBJS BUILD_CC BUILD_CFLAGS BUILD_CPPFLAGS BUILD_LDFLAGS BUILD_LIBS LIBOBJS LTLIBOBJS'
 ac_subst_files='BIND9_MAKE_INCLUDES BIND9_MAKE_RULES LIBISC_API LIBISCCC_API LIBISCCFG_API LIBDNS_API LIBBIND9_API LIBLWRES_API DLZ_DRIVER_RULES'
 
 # Initialize some variables set by options.
@@ -28049,6 +28049,68 @@ echo $ECHO_N "checking compiler support for inline assembly code... $ECHO_C" >&6
 			# We can share the same code for gcc with x86_32
 			arch=x86_32
 		fi
+		if test $arch = "powerpc"; then
+			#
+			# The MacOS (and maybe others) uses "r0" for register
+			# zero. Under linux/ibm it is "0" for register 0.
+			# Probe to see if we have a MacOS style assembler.
+			#
+			echo "$as_me:$LINENO: checking Checking for MacOS style assembler syntax" >&5
+echo $ECHO_N "checking Checking for MacOS style assembler syntax... $ECHO_C" >&6
+			cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h.  */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+			__asm__ volatile ("li r0, 0x0\n"::);
+
+  ;
+  return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
+  (eval $ac_compile) 2>conftest.er1
+  ac_status=$?
+  grep -v '^ *+' conftest.er1 >conftest.err
+  rm -f conftest.er1
+  cat conftest.err >&5
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); } &&
+	 { ac_try='test -z "$ac_c_werror_flag"
+			 || test ! -s conftest.err'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; } &&
+	 { ac_try='test -s conftest.$ac_objext'
+  { (eval echo "$as_me:$LINENO: \"$ac_try\"") >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; }; then
+
+			echo "$as_me:$LINENO: result: yes" >&5
+echo "${ECHO_T}yes" >&6
+			compiler="mac"
+			ISC_PLATFORM_USEMACASM="#define ISC_PLATFORM_USEMACASM 1"
+
+else
+  echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+echo "$as_me:$LINENO: result: no" >&5
+echo "${ECHO_T}no" >&6
+fi
+rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
+		fi
 	else
 		case "$host" in
 		alpha*-dec-osf*)
@@ -28117,6 +28179,8 @@ rm -f conftest.err conftest.$ac_objext conftest.$ac_ext
 		;;
 	aix)
 		;;
+	mac)
+		;;
 	*)
 		# See if the generic __asm function works.  If not,
 		# we need to disable the atomic operations.
@@ -28196,6 +28260,7 @@ fi
 
 
 
+
 ISC_ARCH_DIR=$arch
 
 
@@ -30744,6 +30809,7 @@ s,@ISC_PLATFORM_HAVEATOMICSTORE@,$ISC_PLATFORM_HAVEATOMICSTORE,;t t
 s,@ISC_PLATFORM_USEGCCASM@,$ISC_PLATFORM_USEGCCASM,;t t
 s,@ISC_PLATFORM_USEOSFASM@,$ISC_PLATFORM_USEOSFASM,;t t
 s,@ISC_PLATFORM_USESTDASM@,$ISC_PLATFORM_USESTDASM,;t t
+s,@ISC_PLATFORM_USEMACASM@,$ISC_PLATFORM_USEMACASM,;t t
 s,@ISC_ARCH_DIR@,$ISC_ARCH_DIR,;t t
 s,@LATEX@,$LATEX,;t t
 s,@PDFLATEX@,$PDFLATEX,;t t
diff --git a/configure.in b/configure.in
index b9d2e38a86..4059466e0c 100644
--- a/configure.in
+++ b/configure.in
@@ -18,7 +18,7 @@ AC_DIVERT_PUSH(1)dnl
 esyscmd([sed "s/^/# /" COPYRIGHT])dnl
 AC_DIVERT_POP()dnl
 
-AC_REVISION($Revision: 1.355.18.65 $)
+AC_REVISION($Revision: 1.355.18.66 $)
 
 AC_INIT(lib/dns/name.c)
 AC_PREREQ(2.59)
@@ -1960,6 +1960,21 @@ if test "$have_atomic" = "yes"; then
 			# We can share the same code for gcc with x86_32
 			arch=x86_32
 		fi
+		if test $arch = "powerpc"; then
+			#
+			# The MacOS (and maybe others) uses "r0" for register
+			# zero. Under linux/ibm it is "0" for register 0.
+			# Probe to see if we have a MacOS style assembler.
+			#
+			AC_MSG_CHECKING([Checking for MacOS style assembler syntax])
+			AC_TRY_COMPILE(, [
+			__asm__ volatile ("li r0, 0x0\n"::);
+			], [
+			AC_MSG_RESULT(yes)
+			compiler="mac"
+			ISC_PLATFORM_USEMACASM="#define ISC_PLATFORM_USEMACASM 1"
+			], [AC_MSG_RESULT(no)])
+		fi
 	else
 		case "$host" in
 		alpha*-dec-osf*)
@@ -1986,6 +2001,8 @@ if test "$have_atomic" = "yes"; then
 		;;
 	aix)
 		;;
+	mac)
+		;;
 	*)
 		# See if the generic __asm function works.  If not,
 		# we need to disable the atomic operations.
@@ -2020,6 +2037,7 @@ AC_SUBST(ISC_PLATFORM_HAVEATOMICSTORE)
 AC_SUBST(ISC_PLATFORM_USEGCCASM)
 AC_SUBST(ISC_PLATFORM_USEOSFASM)
 AC_SUBST(ISC_PLATFORM_USESTDASM)
+AC_SUBST(ISC_PLATFORM_USEMACASM)
 
 ISC_ARCH_DIR=$arch
 AC_SUBST(ISC_ARCH_DIR)
diff --git a/lib/isc/include/isc/platform.h.in b/lib/isc/include/isc/platform.h.in
index c2b0353d00..78155bfb3a 100644
--- a/lib/isc/include/isc/platform.h.in
+++ b/lib/isc/include/isc/platform.h.in
@@ -15,7 +15,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: platform.h.in,v 1.34.18.5 2005/06/16 22:01:02 jinmei Exp $ */
+/* $Id: platform.h.in,v 1.34.18.6 2007/02/12 00:52:58 marka Exp $ */
 
 #ifndef ISC_PLATFORM_H
 #define ISC_PLATFORM_H 1
@@ -250,6 +250,12 @@
  */
 @ISC_PLATFORM_USESTDASM@
 
+/*
+ * Define if MacOS style of PPC assembly must be used.
+ * e.g. "r6", not "6", for register six.
+ */
+@ISC_PLATFORM_USEMACASM@
+
 #ifndef ISC_PLATFORM_USEDECLSPEC
 #define LIBISC_EXTERNAL_DATA
 #define LIBDNS_EXTERNAL_DATA
diff --git a/lib/isc/powerpc/include/isc/atomic.h b/lib/isc/powerpc/include/isc/atomic.h
index 67b9a42214..d9c3f17d2a 100644
--- a/lib/isc/powerpc/include/isc/atomic.h
+++ b/lib/isc/powerpc/include/isc/atomic.h
@@ -14,7 +14,7 @@
  * PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: atomic.h,v 1.1.6.3 2005/09/01 03:39:13 marka Exp $ */
+/* $Id: atomic.h,v 1.1.6.4 2007/02/12 00:52:58 marka Exp $ */
 
 #ifndef ISC_ATOMIC_H
 #define ISC_ATOMIC_H 1
@@ -67,18 +67,27 @@ isc_atomic_cmpxchg(atomic_p p, int old, int new) {
         return (orig);
 }
 
-#elif ISC_PLATFORM_USEGCCASM
+#elif defined(ISC_PLATFORM_USEGCCASM) || defined(ISC_PLATFORM_USEMACASM)
 static inline isc_int32_t
 isc_atomic_xadd(isc_int32_t *p, isc_int32_t val) {
 	isc_int32_t orig;
 
 	__asm__ volatile (
+#ifdef ISC_PLATFORM_USEMACASM
 		"1:"
 		"lwarx r6, 0, %1\n"
 	    	"mr %0, r6\n"
 		"add r6, r6, %2\n"
 		"stwcx. r6, 0, %1\n"
 		"bne- 1b"
+#else
+		"1:"
+		"lwarx 6, 0, %1\n"
+	    	"mr %0, 6\n"
+		"add 6, 6, %2\n"
+		"stwcx. 6, 0, %1\n"
+		"bne- 1b"
+#endif
 		: "=&r"(orig)
 		: "r"(p), "r"(val)
 		: "r6", "memory"
@@ -90,11 +99,19 @@ isc_atomic_xadd(isc_int32_t *p, isc_int32_t val) {
 static inline void
 isc_atomic_store(void *p, isc_int32_t val) {
 	__asm__ volatile (
+#ifdef ISC_PLATFORM_USEMACASM
 		"1:"
 		"lwarx r6, 0, %0\n"
 		"lwz r6, %1\n"
 		"stwcx. r6, 0, %0\n"
 		"bne- 1b"
+#else
+		"1:"
+		"lwarx 6, 0, %0\n"
+		"lwz 6, %1\n"
+		"stwcx. 6, 0, %0\n"
+		"bne- 1b"
+#endif
 		:
 		: "r"(p), "m"(val)
 		: "r6", "memory"
@@ -106,6 +123,7 @@ isc_atomic_cmpxchg(isc_int32_t *p, isc_int32_t cmpval, isc_int32_t val) {
 	isc_int32_t orig;
 
 	__asm__ volatile (
+#ifdef ISC_PLATFORM_USEMACASM
 		"1:"
 		"lwarx r6, 0, %1\n"
 		"mr %0,r6\n"
@@ -115,6 +133,17 @@ isc_atomic_cmpxchg(isc_int32_t *p, isc_int32_t cmpval, isc_int32_t val) {
 		"stwcx. r6, 0, %1\n"
 		"bne- 1b\n"
 		"2:"
+#else
+		"1:"
+		"lwarx 6, 0, %1\n"
+		"mr %0,6\n"
+		"cmpw 6, %2\n"
+		"bne 2f\n"
+		"mr 6, %3\n"
+		"stwcx. 6, 0, %1\n"
+		"bne- 1b\n"
+		"2:"
+#endif
 		: "=&r" (orig)
 		: "r"(p), "r"(cmpval), "r"(val)
 		: "r6", "memory"