Index: lib/Target/Mips/AsmParser/MipsAsmParser.cpp
===================================================================
--- lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -1103,8 +1103,6 @@
   unsigned ImmOffset, HiOffset, LoOffset;
   const MCExpr *ExprOffset;
   unsigned TmpRegNum;
-  unsigned AtRegNum = getReg(
-      (isGP64()) ? Mips::GPR64RegClassID : Mips::GPR32RegClassID, getATReg());
   // 1st operand is either the source or destination register.
   assert(Inst.getOperand(0).isReg() && "expected register operand kind");
   unsigned RegOpNum = Inst.getOperand(0).getReg();
@@ -1127,7 +1125,12 @@
   // 1st instruction in expansion is LUi. For load instruction we can use
   // the dst register as a temporary if base and dst are different,
   // but for stores we must use $at.
-  TmpRegNum = (isLoad && (BaseRegNum != RegOpNum)) ? RegOpNum : AtRegNum;
+  if (isLoad && (BaseRegNum != RegOpNum))
+    TmpRegNum = RegOpNum;
+  else
+    TmpRegNum = getReg(
+      (isGP64()) ? Mips::GPR64RegClassID : Mips::GPR32RegClassID, getATReg());
+
   TempInst.setOpcode(Mips::LUi);
   TempInst.addOperand(MCOperand::CreateReg(TmpRegNum));
   if (isImmOpnd)
Index: test/MC/Mips/mips-expansions.s
===================================================================
--- test/MC/Mips/mips-expansions.s
+++ test/MC/Mips/mips-expansions.s
@@ -44,7 +44,9 @@
     la $a0, 20($a1)
     la $7,65538($8)
 
+    .set noat
     lw  $t2, symbol($a0)
+    .set at
     sw  $t2, symbol($t1)
 
     lw  $t2, 655483($a0)