[sil-combine] Enable select_enum canonicalization in OSSA.

Author: gottesmm

lib/SILOptimizer/SILCombiner/SILCombinerMiscVisitors.cpp

@@ -1887,9 +1887,6 @@ SILInstruction *SILCombiner::visitCondBranchInst(CondBranchInst *CBI) {
 }
 
 SILInstruction *SILCombiner::visitSelectEnumInst(SelectEnumInst *SEI) {
-  if (SEI->getFunction()->hasOwnership())
-    return nullptr;
-
   // Canonicalize a select_enum: if the default refers to exactly one case, then
   // replace the default with that case.
   if (SEI->hasDefault()) {

test/SILOptimizer/sil_combine_enums_ossa.sil

@@ -106,9 +106,9 @@ enum E {
 }
 
 // CHECK-LABEL: sil [ossa] @canonicalize_select_enum
-// XHECK: select_enum {{.*}} case #E.E2!enumelt:
-// XHECK: return
-
+// CHECK: select_enum {{.*}} case #E.E2!enumelt:
+// CHECK: return
+// CHECK: } // end sil function 'canonicalize_select_enum'
 sil [ossa] @canonicalize_select_enum : $@convention(thin) (E) -> Int32 {
 bb0(%0 : $E):
   %1 = integer_literal $Builtin.Int32, 0