Index: lib/Target/PowerPC/PPCISelLowering.cpp
===================================================================
--- lib/Target/PowerPC/PPCISelLowering.cpp
+++ lib/Target/PowerPC/PPCISelLowering.cpp
@@ -613,10 +613,10 @@
     setOperationAction(ISD::READCYCLECOUNTER, MVT::i64, Legal);
   }
 
-  setOperationAction(ISD::ATOMIC_LOAD,  MVT::i32, Expand);
-  setOperationAction(ISD::ATOMIC_STORE, MVT::i32, Expand);
-  setOperationAction(ISD::ATOMIC_LOAD,  MVT::i64, Expand);
-  setOperationAction(ISD::ATOMIC_STORE, MVT::i64, Expand);
+  if (!isPPC64) {
+    setOperationAction(ISD::ATOMIC_LOAD,  MVT::i64, Expand);
+    setOperationAction(ISD::ATOMIC_STORE, MVT::i64, Expand);
+  }
 
   setBooleanContents(ZeroOrOneBooleanContent);
   // Altivec instructions set fields to all zeros or all ones.
Index: lib/Target/PowerPC/PPCInstr64Bit.td
===================================================================
--- lib/Target/PowerPC/PPCInstr64Bit.td
+++ lib/Target/PowerPC/PPCInstr64Bit.td
@@ -1135,3 +1135,9 @@
 def : Pat<(unaligned4store i64:$rS, xoaddr:$dst),
           (STDX $rS, xoaddr:$dst)>;
 
+// 64-bits atomic loads and stores
+def : Pat<(atomic_load_64 ixaddr:$src), (LD  memrix:$src)>;
+def : Pat<(atomic_load_64 xaddr:$src),  (LDX memrr:$src)>;
+
+def : Pat<(atomic_store_64 ixaddr:$ptr, i64:$val), (STD  g8rc:$val, memrix:$ptr)>;
+def : Pat<(atomic_store_64 xaddr:$ptr,  i64:$val), (STDX g8rc:$val, memrr:$ptr)>;
Index: lib/Target/PowerPC/PPCInstrInfo.td
===================================================================
--- lib/Target/PowerPC/PPCInstrInfo.td
+++ lib/Target/PowerPC/PPCInstrInfo.td
@@ -3695,3 +3695,19 @@
 defm : TrapExtendedMnemonic<"lnl", 5>;
 defm : TrapExtendedMnemonic<"lng", 6>;
 defm : TrapExtendedMnemonic<"u", 31>;
+
+// Atomic loads
+def : Pat<(atomic_load_8  iaddr:$src), (LBZ  memri:$src)>;
+def : Pat<(atomic_load_16 iaddr:$src), (LHZ  memri:$src)>;
+def : Pat<(atomic_load_32 iaddr:$src), (LWZ  memri:$src)>;
+def : Pat<(atomic_load_8  xaddr:$src), (LBZX memrr:$src)>;
+def : Pat<(atomic_load_16 xaddr:$src), (LHZX memrr:$src)>;
+def : Pat<(atomic_load_32 xaddr:$src), (LWZX memrr:$src)>;
+
+// Atomic stores
+def : Pat<(atomic_store_8  iaddr:$ptr, i32:$val), (STB  gprc:$val, memri:$ptr)>;
+def : Pat<(atomic_store_16 iaddr:$ptr, i32:$val), (STH  gprc:$val, memri:$ptr)>;
+def : Pat<(atomic_store_32 iaddr:$ptr, i32:$val), (STW  gprc:$val, memri:$ptr)>;
+def : Pat<(atomic_store_8  xaddr:$ptr, i32:$val), (STBX gprc:$val, memrr:$ptr)>;
+def : Pat<(atomic_store_16 xaddr:$ptr, i32:$val), (STHX gprc:$val, memrr:$ptr)>;
+def : Pat<(atomic_store_32 xaddr:$ptr, i32:$val), (STWX gprc:$val, memrr:$ptr)>;
Index: test/CodeGen/PowerPC/atomic-2.ll
===================================================================
--- test/CodeGen/PowerPC/atomic-2.ll
+++ test/CodeGen/PowerPC/atomic-2.ll
@@ -30,8 +30,9 @@
 entry:
 ; CHECK: @atomic_store
   store atomic i64 %val, i64* %mem release, align 64
-; CHECK: ldarx
-; CHECK: stdcx.
+; CHECK: sync 1
+; CHECK-NOT: stdcx
+; CHECK: std
   ret void
 }
 
@@ -39,9 +40,9 @@
 entry:
 ; CHECK: @atomic_load
   %tmp = load atomic i64* %mem acquire, align 64
-; CHECK: ldarx
-; CHECK: stdcx.
-; CHECK: stdcx.
+; CHECK-NOT: ldarx
+; CHECK: ld
+; CHECK: sync 1
   ret i64 %tmp
 }
 
Index: test/CodeGen/PowerPC/atomics.ll
===================================================================
--- test/CodeGen/PowerPC/atomics.ll
+++ test/CodeGen/PowerPC/atomics.ll
@@ -11,18 +11,21 @@
 ; We also vary orderings to check for barriers.
 define i8 @load_i8_unordered(i8* %mem) {
 ; CHECK-LABEL: load_i8_unordered
+; CHECK: lbz
 ; CHECK-NOT: sync
   %val = load atomic i8* %mem unordered, align 1
   ret i8 %val
 }
 define i16 @load_i16_monotonic(i16* %mem) {
 ; CHECK-LABEL: load_i16_monotonic
+; CHECK: lhz
 ; CHECK-NOT: sync
   %val = load atomic i16* %mem monotonic, align 2
   ret i16 %val
 }
 define i32 @load_i32_acquire(i32* %mem) {
 ; CHECK-LABEL: load_i32_acquire
+; CHECK: lwz
   %val = load atomic i32* %mem acquire, align 4
 ; CHECK: sync 1
   ret i32 %val
@@ -30,6 +33,9 @@
 define i64 @load_i64_seq_cst(i64* %mem) {
 ; CHECK-LABEL: load_i64_seq_cst
 ; CHECK: sync 0
+; PPC32: __sync_
+; PPC64-NOT: __sync_
+; PPC64: ld
   %val = load atomic i64* %mem seq_cst, align 8
 ; CHECK: sync 1
   ret i64 %val
@@ -39,24 +45,30 @@
 define void @store_i8_unordered(i8* %mem) {
 ; CHECK-LABEL: store_i8_unordered
 ; CHECK-NOT: sync
+; CHECK: stb
   store atomic i8 42, i8* %mem unordered, align 1
   ret void
 }
 define void @store_i16_monotonic(i16* %mem) {
 ; CHECK-LABEL: store_i16_monotonic
 ; CHECK-NOT: sync
+; CHECK: sth
   store atomic i16 42, i16* %mem monotonic, align 2
   ret void
 }
 define void @store_i32_release(i32* %mem) {
 ; CHECK-LABEL: store_i32_release
 ; CHECK: sync 1
+; CHECK: stw
   store atomic i32 42, i32* %mem release, align 4
   ret void
 }
 define void @store_i64_seq_cst(i64* %mem) {
 ; CHECK-LABEL: store_i64_seq_cst
 ; CHECK: sync 0
+; PPC32: __sync_
+; PPC64-NOT: __sync_
+; PPC64: std
   store atomic i64 42, i64* %mem seq_cst, align 8
   ret void
 }
Index: test/CodeGen/PowerPC/pr15630.ll
===================================================================
--- test/CodeGen/PowerPC/pr15630.ll
+++ test/CodeGen/PowerPC/pr15630.ll
@@ -13,4 +13,5 @@
   ret void
 }
 
-; CHECK: stwcx.
+; CHECK: sync
+; CHECK: stb