iconv: Remove _STRING_ARCH_unaligned usage for get/set macros

And use a packed structure instead.  The compiler generates optimized
unaligned code if the architecture supports it.

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Wilco Dijkstra  <Wilco.Dijkstra@arm.com>

3 files changed, 28 insertions, 140 deletions

diff --git a/iconv/gconv_int.h b/iconv/gconv_int.h
index da792a9..4b247a8 100644
--- a/iconv/gconv_int.h
+++ b/iconv/gconv_int.h
@@ -26,6 +26,34 @@
 
 __BEGIN_DECLS
 
+/* We have to provide support for machines which are not able to handled
+   unaligned memory accesses.  Some of the character encodings have
+   representations with a fixed width of 2 or 4 bytes.  */
+#define get16(addr)							\
+({									\
+  const struct { uint16_t r; } __attribute__ ((__packed__)) *__ptr	\
+    = (__typeof(__ptr))(addr);						\
+  __ptr->r;								\
+})
+#define get32(addr)							\
+({									\
+  const struct { uint32_t r; } __attribute__ ((__packed__)) *__ptr	\
+    = (__typeof(__ptr))(addr);						\
+  __ptr->r;								\
+})
+
+#define put16(addr, val)						\
+do {									\
+   struct { uint16_t r; } __attribute__ ((__packed__)) *__ptr		\
+    = (__typeof(__ptr))(addr);						\
+   __ptr->r = val;							\
+} while (0)
+#define put32(addr, val)						\
+do {									\
+   struct { uint32_t r; } __attribute__ ((__packed__)) *__ptr		\
+    = (__typeof(__ptr))(addr);						\
+   __ptr->r = val;							\
+} while (0)
 
 /* Structure for alias definition.  Simply two strings.  */
 struct gconv_alias
diff --git a/iconv/loop.c b/iconv/loop.c
index 963c59c..9d8a7cc 100644
--- a/iconv/loop.c
+++ b/iconv/loop.c
@@ -57,75 +57,10 @@
 #include <stddef.h>
 #include <libc-diag.h>
 
-/* We have to provide support for machines which are not able to handled
-   unaligned memory accesses.  Some of the character encodings have
-   representations with a fixed width of 2 or 4 bytes.  But if we cannot
-   access unaligned memory we still have to read byte-wise.  */
 #undef FCTNAME2
 #if _STRING_ARCH_unaligned || !defined DEFINE_UNALIGNED
-/* We can handle unaligned memory access.  */
-# define get16(addr) *((const uint16_t *) (addr))
-# define get32(addr) *((const uint32_t *) (addr))
-
-/* We need no special support for writing values either.  */
-# define put16(addr, val) *((uint16_t *) (addr)) = (val)
-# define put32(addr, val) *((uint32_t *) (addr)) = (val)
-
 # define FCTNAME2(name) name
 #else
-/* Distinguish between big endian and little endian.  */
-# if __BYTE_ORDER == __LITTLE_ENDIAN
-#  define get16(addr) \
-     (((const unsigned char *) (addr))[1] << 8				      \
-      | ((const unsigned char *) (addr))[0])
-#  define get32(addr) \
-     (((((const unsigned char *) (addr))[3] << 8			      \
-	| ((const unsigned char *) (addr))[2]) << 8			      \
-       | ((const unsigned char *) (addr))[1]) << 8			      \
-      | ((const unsigned char *) (addr))[0])
-
-#  define put16(addr, val) \
-     ({ uint16_t __val = (val);						      \
-	((unsigned char *) (addr))[0] = __val;				      \
-	((unsigned char *) (addr))[1] = __val >> 8;			      \
-	(void) 0; })
-#  define put32(addr, val) \
-     ({ uint32_t __val = (val);						      \
-	((unsigned char *) (addr))[0] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[1] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[2] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[3] = __val;				      \
-	(void) 0; })
-# else
-#  define get16(addr) \
-     (((const unsigned char *) (addr))[0] << 8				      \
-      | ((const unsigned char *) (addr))[1])
-#  define get32(addr) \
-     (((((const unsigned char *) (addr))[0] << 8			      \
-	| ((const unsigned char *) (addr))[1]) << 8			      \
-       | ((const unsigned char *) (addr))[2]) << 8			      \
-      | ((const unsigned char *) (addr))[3])
-
-#  define put16(addr, val) \
-     ({ uint16_t __val = (val);						      \
-	((unsigned char *) (addr))[1] = __val;				      \
-	((unsigned char *) (addr))[0] = __val >> 8;			      \
-	(void) 0; })
-#  define put32(addr, val) \
-     ({ uint32_t __val = (val);						      \
-	((unsigned char *) (addr))[3] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[2] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[1] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[0] = __val;				      \
-	(void) 0; })
-# endif
-
 # define FCTNAME2(name) name##_unaligned
 #endif
 #define FCTNAME(name) FCTNAME2(name)
@@ -349,10 +284,6 @@ FCTNAME (LOOPFCT) (struct __gconv_step *step,
 #if !defined DEFINE_UNALIGNED && !_STRING_ARCH_unaligned \
     && MIN_NEEDED_INPUT != 1 && MAX_NEEDED_INPUT % MIN_NEEDED_INPUT == 0 \
     && MIN_NEEDED_OUTPUT != 1 && MAX_NEEDED_OUTPUT % MIN_NEEDED_OUTPUT == 0
-# undef get16
-# undef get32
-# undef put16
-# undef put32
 # undef unaligned
 
 # define DEFINE_UNALIGNED
@@ -540,8 +471,4 @@ gconv_btowc (struct __gconv_step *step, unsigned char c)
 #undef LOOP_NEED_STATE
 #undef LOOP_NEED_FLAGS
 #undef LOOP_NEED_DATA
-#undef get16
-#undef get32
-#undef put16
-#undef put32
 #undef unaligned
diff --git a/iconv/skeleton.c b/iconv/skeleton.c
index 673b474..9423d3f 100644
--- a/iconv/skeleton.c
+++ b/iconv/skeleton.c
@@ -204,73 +204,6 @@
 #endif
 
 
-/* Define macros which can access unaligned buffers.  These macros are
-   supposed to be used only in code outside the inner loops.  For the inner
-   loops we have other definitions which allow optimized access.  */
-#if _STRING_ARCH_unaligned
-/* We can handle unaligned memory access.  */
-# define get16u(addr) *((const uint16_t *) (addr))
-# define get32u(addr) *((const uint32_t *) (addr))
-
-/* We need no special support for writing values either.  */
-# define put16u(addr, val) *((uint16_t *) (addr)) = (val)
-# define put32u(addr, val) *((uint32_t *) (addr)) = (val)
-#else
-/* Distinguish between big endian and little endian.  */
-# if __BYTE_ORDER == __LITTLE_ENDIAN
-#  define get16u(addr) \
-     (((const unsigned char *) (addr))[1] << 8				      \
-      | ((const unsigned char *) (addr))[0])
-#  define get32u(addr) \
-     (((((const unsigned char *) (addr))[3] << 8			      \
-	| ((const unsigned char *) (addr))[2]) << 8			      \
-       | ((const unsigned char *) (addr))[1]) << 8			      \
-      | ((const unsigned char *) (addr))[0])
-
-#  define put16u(addr, val) \
-     ({ uint16_t __val = (val);						      \
-	((unsigned char *) (addr))[0] = __val;				      \
-	((unsigned char *) (addr))[1] = __val >> 8;			      \
-	(void) 0; })
-#  define put32u(addr, val) \
-     ({ uint32_t __val = (val);						      \
-	((unsigned char *) (addr))[0] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[1] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[2] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[3] = __val;				      \
-	(void) 0; })
-# else
-#  define get16u(addr) \
-     (((const unsigned char *) (addr))[0] << 8				      \
-      | ((const unsigned char *) (addr))[1])
-#  define get32u(addr) \
-     (((((const unsigned char *) (addr))[0] << 8			      \
-	| ((const unsigned char *) (addr))[1]) << 8			      \
-       | ((const unsigned char *) (addr))[2]) << 8			      \
-      | ((const unsigned char *) (addr))[3])
-
-#  define put16u(addr, val) \
-     ({ uint16_t __val = (val);						      \
-	((unsigned char *) (addr))[1] = __val;				      \
-	((unsigned char *) (addr))[0] = __val >> 8;			      \
-	(void) 0; })
-#  define put32u(addr, val) \
-     ({ uint32_t __val = (val);						      \
-	((unsigned char *) (addr))[3] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[2] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[1] = __val;				      \
-	__val >>= 8;							      \
-	((unsigned char *) (addr))[0] = __val;				      \
-	(void) 0; })
-# endif
-#endif
-
-
 /* For conversions from a fixed width character set to another fixed width
    character set we can define RESET_INPUT_BUFFER in a very fast way.  */
 #if !defined RESET_INPUT_BUFFER && !defined SAVE_RESET_STATE