diff --git a/gcc/testsuite/gcc.dg/di-longlong64-sync-1.c b/gcc/testsuite/gcc.dg/di-longlong64-sync-1.c
new file mode 100644
index 0000000..82a4ea2
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/di-longlong64-sync-1.c
@@ -0,0 +1,164 @@
+/* { dg-do run } */
+/* { dg-require-effective-target sync_longlong } */
+/* { dg-options "-std=gnu99" } */
+/* { dg-message "note: '__sync_fetch_and_nand' changed semantics in GCC 4.4" "" { target *-*-* } 0 } */
+/* { dg-message "note: '__sync_nand_and_fetch' changed semantics in GCC 4.4" "" { target *-*-* } 0 } */
+
+
+/* Test basic functionality of the intrinsics.  The operations should
+   not be optimized away if no one checks the return values.  */
+
+/* Based on ia64-sync-[12].c, but 1) long on ARM is 32 bit so use long long
+   (an explicit 64bit type maybe a better bet) and 2) Use values that cross
+   the 32bit boundary and cause carries since the actual maths are done as
+   pairs of 32 bit instructions.  */
+
+/* Note: This file is #included by some of the ARM tests.  */
+
+__extension__ typedef __SIZE_TYPE__ size_t;
+
+extern void abort (void);
+extern void *memcpy (void *, const void *, size_t);
+extern int memcmp (const void *, const void *, size_t);
+
+/* Temporary space where the work actually gets done.  */
+static long long AL[24];
+/* Values copied into AL before we start.  */
+static long long init_di[24] = { 0x100000002ll, 0x200000003ll, 0, 1,
+
+				 0x100000002ll, 0x100000002ll,
+				 0x100000002ll, 0x100000002ll,
+
+				 0, 0x1000e0de0000ll,
+				 42 , 0xc001c0de0000ll,
+
+				 -1ll, 0, 0xff00ff0000ll, -1ll,
+
+				 0, 0x1000e0de0000ll,
+				 42 , 0xc001c0de0000ll,
+
+				 -1ll, 0, 0xff00ff0000ll, -1ll};
+/* This is what should be in AL at the end.  */
+static long long test_di[24] = { 0x1234567890ll, 0x1234567890ll, 1, 0,
+
+				 0x100000002ll, 0x100000002ll,
+				 0x100000002ll, 0x100000002ll,
+
+				 1, 0xc001c0de0000ll,
+				 20, 0x1000e0de0000ll,
+
+				 0x300000007ll , 0x500000009ll,
+				 0xf100ff0001ll, ~0xa00000007ll,
+
+				 1, 0xc001c0de0000ll,
+				 20, 0x1000e0de0000ll,
+
+				 0x300000007ll , 0x500000009ll,
+				 0xf100ff0001ll, ~0xa00000007ll };
+
+/* First check they work in terms of what they do to memory.  */
+static void
+do_noret_di (void)
+{
+  __sync_val_compare_and_swap (AL+0, 0x100000002ll, 0x1234567890ll);
+  __sync_bool_compare_and_swap (AL+1, 0x200000003ll, 0x1234567890ll);
+  __sync_lock_test_and_set (AL+2, 1);
+  __sync_lock_release (AL+3);
+
+  /* The following tests should not change the value since the
+     original does NOT match.  */
+  __sync_val_compare_and_swap (AL+4, 0x000000002ll, 0x1234567890ll);
+  __sync_val_compare_and_swap (AL+5, 0x100000000ll, 0x1234567890ll);
+  __sync_bool_compare_and_swap (AL+6, 0x000000002ll, 0x1234567890ll);
+  __sync_bool_compare_and_swap (AL+7, 0x100000000ll, 0x1234567890ll);
+
+  __sync_fetch_and_add (AL+8, 1);
+  __sync_fetch_and_add (AL+9, 0xb000e0000000ll); /* + to both halves & carry.  */
+  __sync_fetch_and_sub (AL+10, 22);
+  __sync_fetch_and_sub (AL+11, 0xb000e0000000ll);
+
+  __sync_fetch_and_and (AL+12, 0x300000007ll);
+  __sync_fetch_and_or (AL+13, 0x500000009ll);
+  __sync_fetch_and_xor (AL+14, 0xe00000001ll);
+  __sync_fetch_and_nand (AL+15, 0xa00000007ll);
+
+  /* These should be the same as the fetch_and_* cases except for
+     return value.  */
+  __sync_add_and_fetch (AL+16, 1);
+  /* add to both halves & carry.  */
+  __sync_add_and_fetch (AL+17, 0xb000e0000000ll);
+  __sync_sub_and_fetch (AL+18, 22);
+  __sync_sub_and_fetch (AL+19, 0xb000e0000000ll);
+
+  __sync_and_and_fetch (AL+20, 0x300000007ll);
+  __sync_or_and_fetch (AL+21, 0x500000009ll);
+  __sync_xor_and_fetch (AL+22, 0xe00000001ll);
+  __sync_nand_and_fetch (AL+23, 0xa00000007ll);
+}
+
+/* Now check return values.  */
+static void
+do_ret_di (void)
+{
+  if (__sync_val_compare_and_swap (AL+0, 0x100000002ll, 0x1234567890ll) !=
+	0x100000002ll) abort ();
+  if (__sync_bool_compare_and_swap (AL+1, 0x200000003ll, 0x1234567890ll) !=
+	1) abort ();
+  if (__sync_lock_test_and_set (AL+2, 1) != 0) abort ();
+  __sync_lock_release (AL+3); /* no return value, but keep to match results.  */
+
+  /* The following tests should not change the value since the
+     original does NOT match.  */
+  if (__sync_val_compare_and_swap (AL+4, 0x000000002ll, 0x1234567890ll) !=
+	0x100000002ll) abort ();
+  if (__sync_val_compare_and_swap (AL+5, 0x100000000ll, 0x1234567890ll) !=
+	0x100000002ll) abort ();
+  if (__sync_bool_compare_and_swap (AL+6, 0x000000002ll, 0x1234567890ll) !=
+	0) abort ();
+  if (__sync_bool_compare_and_swap (AL+7, 0x100000000ll, 0x1234567890ll) !=
+	0) abort ();
+
+  if (__sync_fetch_and_add (AL+8, 1) != 0) abort ();
+  if (__sync_fetch_and_add (AL+9, 0xb000e0000000ll) != 0x1000e0de0000ll) abort ();
+  if (__sync_fetch_and_sub (AL+10, 22) != 42) abort ();
+  if (__sync_fetch_and_sub (AL+11, 0xb000e0000000ll) != 0xc001c0de0000ll)
+	abort ();
+
+  if (__sync_fetch_and_and (AL+12, 0x300000007ll) != -1ll) abort ();
+  if (__sync_fetch_and_or (AL+13, 0x500000009ll) != 0) abort ();
+  if (__sync_fetch_and_xor (AL+14, 0xe00000001ll) != 0xff00ff0000ll) abort ();
+  if (__sync_fetch_and_nand (AL+15, 0xa00000007ll) != -1ll) abort ();
+
+  /* These should be the same as the fetch_and_* cases except for
+     return value.  */
+  if (__sync_add_and_fetch (AL+16, 1) != 1) abort ();
+  if (__sync_add_and_fetch (AL+17, 0xb000e0000000ll) != 0xc001c0de0000ll)
+	abort ();
+  if (__sync_sub_and_fetch (AL+18, 22) != 20) abort ();
+  if (__sync_sub_and_fetch (AL+19, 0xb000e0000000ll) != 0x1000e0de0000ll)
+	abort ();
+
+  if (__sync_and_and_fetch (AL+20, 0x300000007ll) != 0x300000007ll) abort ();
+  if (__sync_or_and_fetch (AL+21, 0x500000009ll) != 0x500000009ll) abort ();
+  if (__sync_xor_and_fetch (AL+22, 0xe00000001ll) != 0xf100ff0001ll) abort ();
+  if (__sync_nand_and_fetch (AL+23, 0xa00000007ll) != ~0xa00000007ll) abort ();
+}
+
+int main ()
+{
+  memcpy (AL, init_di, sizeof (init_di));
+
+  do_noret_di ();
+
+  if (memcmp (AL, test_di, sizeof (test_di)))
+    abort ();
+
+  memcpy (AL, init_di, sizeof (init_di));
+
+  do_ret_di ();
+
+  if (memcmp (AL, test_di, sizeof (test_di)))
+    abort ();
+
+  return 0;
+}
diff --git a/gcc/testsuite/gcc.dg/di-sync-multithread.c b/gcc/testsuite/gcc.dg/di-sync-multithread.c
new file mode 100644
index 0000000..c5b3d89
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/di-sync-multithread.c
@@ -0,0 +1,205 @@
+/* { dg-do run } */
+/* { dg-require-effective-target sync_longlong } */
+/* { dg-require-effective-target pthread_h } */
+/* { dg-require-effective-target pthread } */
+/* { dg-options "-pthread -std=gnu99" } */
+
+/* test of long long atomic ops performed in parallel in 3 pthreads
+   david.gilbert@linaro.org */
+
+#include <pthread.h>
+#include <unistd.h>
+
+/*#define DEBUGIT 1 */
+
+#ifdef DEBUGIT
+#include <stdio.h>
+
+#define DOABORT(x,...) {\
+	 fprintf (stderr, x, __VA_ARGS__); fflush (stderr); abort ();\
+	 }
+
+#else
+
+#define DOABORT(x,...) abort ();
+
+#endif
+
+/* Passed to each thread to describe which bits it is going to work on.  */
+struct threadwork {
+  unsigned long long count; /* incremented each time the worker loops.  */
+  unsigned int thread;    /* ID */
+  unsigned int addlsb;    /* 8 bit */
+  unsigned int logic1lsb; /* 5 bit */
+  unsigned int logic2lsb; /* 8 bit */
+};
+
+/* The shared word where all the atomic work is done.  */
+static volatile long long workspace;
+
+/* A shared word to tell the workers to quit when non-0.  */
+static long long doquit;
+
+extern void abort (void);
+
+/* Note this test doesn't test the return values much.  */
+void*
+worker (void* data)
+{
+  struct threadwork *tw = (struct threadwork*)data;
+  long long add1bit = 1ll << tw->addlsb;
+  long long logic1bit = 1ll << tw->logic1lsb;
+  long long logic2bit = 1ll << tw->logic2lsb;
+
+  /* Clear the bits we use.  */
+  __sync_and_and_fetch (&workspace, ~(0xffll * add1bit));
+  __sync_fetch_and_and (&workspace, ~(0x1fll * logic1bit));
+  __sync_fetch_and_and (&workspace, ~(0xffll * logic2bit));
+
+  do
+    {
+      long long tmp1, tmp2, tmp3;
+      /* OK, lets try and do some stuff to the workspace - by the end
+         of the main loop our area should be the same as it is now - i.e. 0.  */
+
+      /* Push the arithmetic section upto 128 - one of the threads will
+         case this to carry accross the 32bit boundary.  */
+      for (tmp2 = 0; tmp2 < 64; tmp2++)
+	{
+	  /* Add 2 using the two different adds.  */
+	  tmp1 = __sync_add_and_fetch (&workspace, add1bit);
+	  tmp3 = __sync_fetch_and_add (&workspace, add1bit);
+
+	  /* The value should be the intermediate add value in both cases.  */
+	  if ((tmp1 & (add1bit * 0xff)) != (tmp3 & (add1bit * 0xff)))
+	    DOABORT ("Mismatch of add intermediates on thread %d "
+			"workspace=0x%llx tmp1=0x%llx "
+			"tmp2=0x%llx tmp3=0x%llx\n",
+			 tw->thread, workspace, tmp1, tmp2, tmp3);
+	}
+
+      /* Set the logic bits.  */
+      tmp2=__sync_or_and_fetch (&workspace,
+			  0x1fll * logic1bit | 0xffll * logic2bit);
+
+      /* Check the logic bits are set and the arithmetic value is correct.  */
+      if ((tmp2 & (0x1fll * logic1bit | 0xffll * logic2bit
+			| 0xffll * add1bit))
+	  != (0x1fll * logic1bit | 0xffll * logic2bit | 0x80ll * add1bit))
+	DOABORT ("Midloop check failed on thread %d "
+			"workspace=0x%llx tmp2=0x%llx "
+			"masktmp2=0x%llx expected=0x%llx\n",
+		tw->thread, workspace, tmp2,
+		tmp2 & (0x1fll * logic1bit | 0xffll * logic2bit |
+			 0xffll * add1bit),
+		(0x1fll * logic1bit | 0xffll * logic2bit | 0x80ll * add1bit));
+
+      /* Pull the arithmetic set back down to 0 - again this should cause a
+	 carry across the 32bit boundary in one thread.  */
+
+      for (tmp2 = 0; tmp2 < 64; tmp2++)
+	{
+	  /* Subtract 2 using the two different subs.  */
+	  tmp1=__sync_sub_and_fetch (&workspace, add1bit);
+	  tmp3=__sync_fetch_and_sub (&workspace, add1bit);
+
+	  /* The value should be the intermediate sub value in both cases.  */
+	  if ((tmp1 & (add1bit * 0xff)) != (tmp3 & (add1bit * 0xff)))
+	    DOABORT ("Mismatch of sub intermediates on thread %d "
+			"workspace=0x%llx tmp1=0x%llx "
+			"tmp2=0x%llx tmp3=0x%llx\n",
+			tw->thread, workspace, tmp1, tmp2, tmp3);
+	}
+
+
+      /* Clear the logic bits.  */
+      __sync_fetch_and_xor (&workspace, 0x1fll * logic1bit);
+      tmp3=__sync_and_and_fetch (&workspace, ~(0xffll * logic2bit));
+
+      /* The logic bits and the arithmetic bits should be zero again.  */
+      if (tmp3 & (0x1fll * logic1bit | 0xffll * logic2bit | 0xffll * add1bit))
+	DOABORT ("End of worker loop; bits none 0 on thread %d "
+			"workspace=0x%llx tmp3=0x%llx "
+			"mask=0x%llx maskedtmp3=0x%llx\n",
+		tw->thread, workspace, tmp3, (0x1fll * logic1bit |
+			0xffll * logic2bit | 0xffll * add1bit),
+		tmp3 & (0x1fll * logic1bit | 0xffll * logic2bit | 0xffll * add1bit));
+
+      __sync_add_and_fetch (&tw->count, 1);
+    }
+  while (!__sync_bool_compare_and_swap (&doquit, 1, 1));
+
+  pthread_exit (0);
+}
+
+int
+main ()
+{
+  /* We have 3 threads doing three sets of operations, an 8 bit
+     arithmetic field, a 5 bit logic field and an 8 bit logic
+     field (just to pack them all in).
+
+  6      5       4       4       3       2       1
+  3      6       8       0       2       4       6       8       0
+  |...,...|...,...|...,...|...,...|...,...|...,...|...,...|...,...
+  - T0   --  T1  -- T2   --T2 --  T0  -*- T2-- T1-- T1   -***- T0-
+   logic2  logic2  arith   log2  arith  log1 log1  arith     log1
+
+  */
+  unsigned int t;
+  long long tmp;
+  int err;
+
+  struct threadwork tw[3]={
+    { 0ll, 0, 27, 0, 56 },
+    { 0ll, 1,  8,16, 48 },
+    { 0ll, 2, 40,21, 35 }
+  };
+
+  pthread_t threads[3];
+
+  __sync_lock_release (&doquit);
+
+  /* Get the work space into a known value - All 1's.  */
+  __sync_lock_release (&workspace); /* Now all 0.  */
+  tmp = __sync_val_compare_and_swap (&workspace, 0, -1ll);
+  if (tmp!=0)
+    DOABORT ("Initial __sync_val_compare_and_swap wasn't 0 workspace=0x%llx "
+		"tmp=0x%llx\n", workspace,tmp);
+
+  for (t = 0; t < 3; t++)
+  {
+    err=pthread_create (&threads[t], NULL , worker, &tw[t]);
+    if (err) DOABORT ("pthread_create failed on thread %d with error %d\n",
+	t, err);
+  };
+
+  sleep (5);
+
+  /* Stop please.  */
+  __sync_lock_test_and_set (&doquit, 1ll);
+
+  for (t = 0; t < 3; t++)
+    {
+      err=pthread_join (threads[t], NULL);
+      if (err)
+	DOABORT ("pthread_join failed on thread %d with error %d\n", t, err);
+    };
+
+  __sync_synchronize ();
+
+  /* OK, so all the workers have finished -
+     the workers should have zero'd their workspace, the unused areas
+     should still be 1.  */
+  if (!__sync_bool_compare_and_swap (&workspace, 0x040000e0ll, 0))
+    DOABORT ("End of run workspace mismatch, got %llx\n", workspace);
+
+  /* All the workers should have done some work.  */
+  for (t = 0; t < 3; t++)
+    {
+      if (tw[t].count == 0) DOABORT ("Worker %d gave 0 count\n", t);
+    };
+
+  return 0;
+}
+
diff --git a/gcc/testsuite/gcc.target/arm/di-longlong64-sync-withhelpers.c b/gcc/testsuite/gcc.target/arm/di-longlong64-sync-withhelpers.c
new file mode 100644
index 0000000..19342bf
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/di-longlong64-sync-withhelpers.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target arm_arch_v5_ok } */
+/* { dg-options "-std=gnu99" } */
+/* { dg-add-options arm_arch_v5 } */
+/* { dg-message "note: '__sync_fetch_and_nand' changed semantics in GCC 4.4" "" { target *-*-* } 0 } */
+/* { dg-message "note: '__sync_nand_and_fetch' changed semantics in GCC 4.4" "" { target *-*-* } 0 } */
+/* { dg-message "file included" "In file included" { target *-*-* } 0 } */
+
+#include "../../gcc.dg/di-longlong64-sync-1.c"
+
+/* On an old ARM we have no ldrexd or strexd so we have to use helpers.  */
+/* { dg-final { scan-assembler-not "ldrexd" } } */
+/* { dg-final { scan-assembler-not "strexd" } } */
+/* { dg-final { scan-assembler "__sync_" } } */
diff --git a/gcc/testsuite/gcc.target/arm/di-longlong64-sync-withldrexd.c b/gcc/testsuite/gcc.target/arm/di-longlong64-sync-withldrexd.c
new file mode 100644
index 0000000..dab6940
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/di-longlong64-sync-withldrexd.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target arm_arm_ok } */
+/* { dg-options "-marm -std=gnu99" } */
+/* { dg-require-effective-target arm_arch_v6k_ok } */
+/* { dg-add-options arm_arch_v6k } */
+/* { dg-message "note: '__sync_fetch_and_nand' changed semantics in GCC 4.4" "" { target *-*-* } 0 } */
+/* { dg-message "note: '__sync_nand_and_fetch' changed semantics in GCC 4.4" "" { target *-*-* } 0 } */
+/* { dg-message "file included" "In file included" { target *-*-* } 0 } */
+
+#include "../../gcc.dg/di-longlong64-sync-1.c"
+
+/* We should be using ldrexd, strexd and no helpers or shorter ldrex.  */
+/* { dg-final { scan-assembler-times "\tldrexd" 46 } } */
+/* { dg-final { scan-assembler-times "\tstrexd" 46 } } */
+/* { dg-final { scan-assembler-not "__sync_" } } */
+/* { dg-final { scan-assembler-not "ldrex\t" } } */
+/* { dg-final { scan-assembler-not "strex\t" } } */
diff --git a/gcc/testsuite/lib/target-supports.exp b/gcc/testsuite/lib/target-supports.exp
index 5d236f7..086fbc9 100644
--- a/gcc/testsuite/lib/target-supports.exp
+++ b/gcc/testsuite/lib/target-supports.exp
@@ -2067,6 +2067,47 @@ proc check_effective_target_arm_fp16_ok { } {
 		check_effective_target_arm_fp16_ok_nocache]
 }
 
+# Creates a series of routines that return 1 if the given architecture
+# can be selected and a routine to give the flags to select that architecture
+# Note: Extra flags may be added to disable options from newer compilers
+# (Thumb in particular - but others may be added in the future)
+# Usage: /* { dg-require-effective-target arm_arch_v5_ok } */
+#        /* { dg-add-options arm_arch_v5 } */
+foreach { armfunc armflag armdef } { v5 "-march=armv5 -marm" __ARM_ARCH_5__
+				     v6 "-march=armv6" __ARM_ARCH_6__
+				     v6k "-march=armv6k" __ARM_ARCH_6K__
+				     v7a "-march=armv7-a" __ARM_ARCH_7A__ } {
+    eval [string map [list FUNC $armfunc FLAG $armflag DEF $armdef ] {
+	proc check_effective_target_arm_arch_FUNC_ok { } {
+	    if { [ string match "*-marm*" "FLAG" ] &&
+		![check_effective_target_arm_arm_ok] } {
+		return 0
+	    }
+	    return [check_no_compiler_messages arm_arch_FUNC_ok assembly {
+		#if !defined (DEF)
+		#error FOO
+		#endif
+	    } "FLAG" ]
+	}
+
+	proc add_options_for_arm_arch_FUNC { flags } {
+	    return "$flags FLAG"
+	}
+    }]
+}
+
+# Return 1 if this is an ARM target where -marm causes ARM to be
+# used (not Thumb)
+
+proc check_effective_target_arm_arm_ok { } {
+    return [check_no_compiler_messages arm_arm_ok assembly {
+	#if !defined (__arm__) || defined (__thumb__) || defined (__thumb2__)
+	#error FOO
+	#endif
+    } "-marm"]
+}
+
+
 # Return 1 is this is an ARM target where -mthumb causes Thumb-1 to be
 # used.
 
@@ -3458,6 +3499,31 @@ proc check_effective_target_sync_int_long { } {
     return $et_sync_int_long_saved
 }
 
+# Return 1 if the target supports atomic operations on "long long" and can
+# execute them
+# So far only put checks in for ARM, others may want to add their own
+proc check_effective_target_sync_longlong { } {
+    return [check_runtime sync_longlong_runtime {
+      #include <stdlib.h>
+      int main ()
+      {
+	long long l1;
+
+	if (sizeof (long long) != 8)
+	  exit (1);
+
+      #ifdef __arm__
+	/* Just check for native; checking for kernel fallback is tricky.  */
+	asm volatile ("ldrexd r0,r1, [%0]" : : "r" (&l1) : "r0", "r1");
+      #else
+      # error "Add other suitable archs here"
+      #endif
+
+	exit (0);
+      }
+    } "" ]
+}
+
 # Return 1 if the target supports atomic operations on "char" and "short".
 
 proc check_effective_target_sync_char_short { } {
