Clean up the architecture-specific makefiles.

Group things appropriately and name each group.

Change-Id: I0da45eb0ccde19c31d5e984d0e6eb3dad26630dc
diff --git a/libc/arch-mips64/mips64.mk b/libc/arch-mips64/mips64.mk
index 230cb26..0d4b727 100644
--- a/libc/arch-mips64/mips64.mk
+++ b/libc/arch-mips64/mips64.mk
@@ -1,13 +1,25 @@
-# mips64 specific configs
+# 64-bit mips.
 
-libc_common_src_files_mips64 := \
+#
+# Default implementations of functions that are commonly optimized.
+#
+
+libc_bionic_src_files_mips64 += \
+    bionic/__memcpy_chk.cpp \
+    bionic/__memset_chk.cpp \
+    bionic/__strcpy_chk.cpp \
+    bionic/__strcat_chk.cpp \
     bionic/memchr.c \
     bionic/memcmp.c \
+    bionic/memcpy.cpp \
     bionic/memmove.c \
     bionic/memrchr.c \
+    bionic/memset.c \
     bionic/strchr.cpp \
     bionic/strnlen.c \
     bionic/strrchr.cpp \
+
+libc_freebsd_src_files_mips64 += \
     upstream-freebsd/lib/libc/string/wcscat.c \
     upstream-freebsd/lib/libc/string/wcschr.c \
     upstream-freebsd/lib/libc/string/wcscmp.c \
@@ -16,6 +28,8 @@
     upstream-freebsd/lib/libc/string/wcsrchr.c \
     upstream-freebsd/lib/libc/string/wmemcmp.c \
     upstream-freebsd/lib/libc/string/wmemmove.c \
+
+libc_openbsd_src_files_mips64 += \
     upstream-openbsd/lib/libc/string/stpcpy.c \
     upstream-openbsd/lib/libc/string/stpncpy.c \
     upstream-openbsd/lib/libc/string/strcat.c \
@@ -28,17 +42,11 @@
     upstream-openbsd/lib/libc/string/strncmp.c \
     upstream-openbsd/lib/libc/string/strncpy.c \
 
-# Fortify implementations of libc functions.
-libc_common_src_files_mips64 += \
-    bionic/__memcpy_chk.cpp \
-    bionic/__memset_chk.cpp \
-    bionic/__strcpy_chk.cpp \
-    bionic/__strcat_chk.cpp \
+#
+# Inherently architecture-specific code.
+#
 
-
-##########################################
-### CPU specific source files
-libc_bionic_src_files_mips64 := \
+libc_bionic_src_files_mips64 += \
     arch-mips64/bionic/__bionic_clone.S \
     arch-mips64/bionic/_exit_with_stack_teardown.S \
     arch-mips64/bionic/__get_sp.S \
@@ -48,25 +56,18 @@
     arch-mips64/bionic/syscall.S \
     arch-mips64/bionic/vfork.S \
 
-# FIXME TODO
-## libc_bionic_src_files_mips64 += arch-mips64/string/memcpy.S
-## libc_bionic_src_files_mips64 += arch-mips64/string/memset.S
-libc_bionic_src_files_mips64 += bionic/memcpy.cpp
-libc_bionic_src_files_mips64 += bionic/memset.c
-
-
 libc_crt_target_cflags_mips64 := \
     $($(my_2nd_arch_prefix)TARGET_GLOBAL_CFLAGS) \
-    -I$(LOCAL_PATH)/arch-mips64/include
+    -I$(LOCAL_PATH)/arch-mips64/include \
 
 libc_crt_target_crtbegin_file_mips64 := \
-    $(LOCAL_PATH)/arch-mips64/bionic/crtbegin.c
+    $(LOCAL_PATH)/arch-mips64/bionic/crtbegin.c \
 
 libc_crt_target_crtbegin_so_file_mips64 := \
-    $(LOCAL_PATH)/arch-common/bionic/crtbegin_so.c
+    $(LOCAL_PATH)/arch-common/bionic/crtbegin_so.c \
 
 libc_crt_target_so_cflags_mips64 := \
-    -fPIC
+    -fPIC \
 
 libc_crt_target_ldflags_mips64 := \
-    -melf64ltsmip
+    -melf64ltsmip \