Provide correct encoding for PPC LWARX instructions.
Patch by Gary Benson!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52828 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCInstrInfo.td b/lib/Target/PowerPC/PPCInstrInfo.td
index 04968ed..d7fe547 100644
--- a/lib/Target/PowerPC/PPCInstrInfo.td
+++ b/lib/Target/PowerPC/PPCInstrInfo.td
@@ -531,8 +531,8 @@
                       PPC970_DGroup_Single;
 
 // Atomic operations.
-def LWARX : Pseudo<(outs GPRC:$rD), (ins memrr:$ptr, i32imm:$label),
-                   "\nLa${label}_entry:\n\tlwarx $rD, $ptr",
+def LWARX : XForm_1<31,  20, (outs GPRC:$rD), (ins memrr:$ptr, i32imm:$label),
+                   "\nLa${label}_entry:\n\tlwarx $rD, $ptr", LdStLWARX,
                    [(set GPRC:$rD, (PPClarx xoaddr:$ptr, imm:$label))]>;
 
 let Defs = [CR0] in {