[SPARC32]: Add __cmpdi2() libcall implementation ala. MIPS.

Device mapper generates calls to this with recent versions
of gcc.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/sparc/lib/Makefile b/arch/sparc/lib/Makefile
index 9ddc5b9ce3bd7eebb01a8209cde9d5bdcffaed6d..76effdbea07576ced82c8415e5d115e2971c6174 100644 (file)
--- a/arch/sparc/lib/Makefile
+++ b/arch/sparc/lib/Makefile
@@ -8,6 +8,7 @@ lib-y := mul.o rem.o sdiv.o udiv.o umul.o urem.o ashrdi3.o memcpy.o memset.o \
          strlen.o checksum.o blockops.o memscan.o memcmp.o strncmp.o \
         strncpy_from_user.o divdi3.o udivdi3.o strlen_user.o \
         copy_user.o locks.o atomic.o \
-        lshrdi3.o ashldi3.o rwsem.o muldi3.o bitext.o
+        lshrdi3.o ashldi3.o rwsem.o muldi3.o bitext.o \
+        cmpdi2.o
 
 obj-y += iomap.o atomic32.o

diff --git a/arch/sparc/lib/cmpdi2.c b/arch/sparc/lib/cmpdi2.c
new file mode 100644 (file)
index 0000000..8c13064
--- /dev/null
+++ b/arch/sparc/lib/cmpdi2.c
@@ -0,0 +1,27 @@
+#include <linux/module.h>
+
+#include "libgcc.h"
+
+word_type __cmpdi2(long long a, long long b)
+{
+       const DWunion au = {
+               .ll = a
+       };
+       const DWunion bu = {
+               .ll = b
+       };
+
+       if (au.s.high < bu.s.high)
+               return 0;
+       else if (au.s.high > bu.s.high)
+               return 2;
+
+       if ((unsigned int) au.s.low < (unsigned int) bu.s.low)
+               return 0;
+       else if ((unsigned int) au.s.low > (unsigned int) bu.s.low)
+               return 2;
+
+       return 1;
+}
+
+EXPORT_SYMBOL(__cmpdi2);

diff --git a/arch/sparc/lib/libgcc.h b/arch/sparc/lib/libgcc.h
new file mode 100644 (file)
index 0000000..b84fd79
--- /dev/null
+++ b/arch/sparc/lib/libgcc.h
@@ -0,0 +1,18 @@
+#ifndef __ASM_LIBGCC_H
+#define __ASM_LIBGCC_H
+
+#include <asm/byteorder.h>
+
+typedef int word_type __attribute__ ((mode (__word__)));
+
+struct DWstruct {
+       int high, low;
+};
+
+typedef union
+{
+       struct DWstruct s;
+       long long ll;
+} DWunion;
+
+#endif /* __ASM_LIBGCC_H */