Make _dl_malloc alignment arch configurable.

From Atsushi Nemoto.

ldso/include/dl-defs.h

@@ -164,4 +164,9 @@ typedef struct {
   ((*SIGNATURE DL_ADDR_TO_FUNC_PTR ((ADDR), (LOADADDR)))(__VA_ARGS__))
 #endif
 
+/* An alignment value for a memory block returned by _dl_malloc. */
+#ifndef DL_MALLOC_ALIGN
+# define DL_MALLOC_ALIGN (__WORDSIZE / 8)
+#endif
+
 #endif	/* _LD_DEFS_H */

ldso/ldso/ldso.c

@@ -950,10 +950,11 @@ void *_dl_malloc(int size)
 	_dl_malloc_addr += size;
 
 	/*
-	 * Align memory to 4 byte boundary.  Some platforms require this,
-	 * others simply get better performance.
+	 * Align memory to DL_MALLOC_ALIGN byte boundary.  Some
+	 * platforms require this, others simply get better
+	 * performance.
 	 */
-	_dl_malloc_addr = (unsigned char *) (((unsigned long) _dl_malloc_addr + 3) & ~(3));
+	_dl_malloc_addr = (unsigned char *) (((unsigned long) _dl_malloc_addr + DL_MALLOC_ALIGN - 1) & ~(DL_MALLOC_ALIGN - 1));
 	return retval;
 }
 

ldso/ldso/mips/dl-sysdep.h

@@ -214,3 +214,7 @@ elf_machine_relative (ElfW(Addr) load_off, const ElfW(Addr) rel_addr,
 {
 	/* No RELATIVE relocs in MIPS? */
 }
+
+#ifdef __mips64
+#define DL_MALLOC_ALIGN 8	/* N64/N32 needs 8 byte alignment */
+#endif