Fix PR14314

- Fix operand order for atomic sub, where the minuend is the value
  loaded from memory and the subtrahend is the parameter specified.

llvm-svn: 167718
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 1f729e3..b35fb51 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -12729,8 +12729,8 @@
   case X86::ATOMSUB6432: {
     unsigned HiOpc;
     unsigned LoOpc = getNonAtomic6432Opcode(Opc, HiOpc);
-    BuildMI(mainMBB, DL, TII->get(LoOpc), t1L).addReg(SrcLoReg).addReg(LoReg);
-    BuildMI(mainMBB, DL, TII->get(HiOpc), t1H).addReg(SrcHiReg).addReg(HiReg);
+    BuildMI(mainMBB, DL, TII->get(LoOpc), t1L).addReg(LoReg).addReg(SrcLoReg);
+    BuildMI(mainMBB, DL, TII->get(HiOpc), t1H).addReg(HiReg).addReg(SrcHiReg);
     break;
   }
   case X86::ATOMNAND6432: {
diff --git a/llvm/test/CodeGen/X86/2010-01-08-Atomic64Bug.ll b/llvm/test/CodeGen/X86/2010-01-08-Atomic64Bug.ll
index 7d1cda3..3d058bc 100644
--- a/llvm/test/CodeGen/X86/2010-01-08-Atomic64Bug.ll
+++ b/llvm/test/CodeGen/X86/2010-01-08-Atomic64Bug.ll
@@ -10,10 +10,10 @@
 ; CHECK: movl ([[REG:%[a-z]+]]), %eax
 ; CHECK: movl 4([[REG]]), %edx
 ; CHECK: LBB0_1:
-; CHECK: movl $1
-; CHECK: addl
-; CHECK: movl $0
-; CHECK: adcl
+; CHECK: movl %eax, %ebx
+; CHECK: addl {{%[a-z]+}}, %ebx
+; CHECK: movl %edx, %ecx
+; CHECK: adcl {{%[a-z]+}}, %ecx
 ; CHECK: lock
 ; CHECK-NEXT: cmpxchg8b ([[REG]])
 ; CHECK-NEXT: jne
diff --git a/llvm/test/CodeGen/X86/pr14314.ll b/llvm/test/CodeGen/X86/pr14314.ll
new file mode 100644
index 0000000..5388a4b
--- /dev/null
+++ b/llvm/test/CodeGen/X86/pr14314.ll
@@ -0,0 +1,13 @@
+; RUN: llc < %s -mtriple=i386-pc-linux -mcpu=corei7 | FileCheck %s
+
+define i64 @atomicSub(i64* %a, i64 %b) nounwind {
+entry:
+  %0 = atomicrmw sub i64* %a, i64 %b seq_cst
+  ret i64 %0
+; CHECK: atomicSub
+; movl %eax, %ebx
+; subl {{%[a-z]+}}, %ebx
+; movl %edx, %ecx
+; sbbl {{%[a-z]+}}, %ecx
+; CHECK: ret
+}