Merge pull request #78197 from atrick/silcombine-markdep

Improve SILCombine mark_dependence: handle address dependence.

Author: atrick

lib/SILOptimizer/SILCombiner/SILCombinerMiscVisitors.cpp

@@ -1961,7 +1961,7 @@ SILInstruction *SILCombiner::visitMarkDependenceInst(MarkDependenceInst *mdi) {
   // does not have a meaning, so just eliminate it.
   {
     SILType baseType = mdi->getBase()->getType();
-    if (baseType.isObject() && baseType.isTrivial(*mdi->getFunction())) {
+    if (baseType.getObjectType().isTrivial(*mdi->getFunction())) {
       SILValue value = mdi->getValue();
       mdi->replaceAllUsesWith(value);
       return eraseInstFromFunction(*mdi);

test/SILOptimizer/sil_combine.sil

@@ -3785,6 +3785,22 @@ bb0(%0 : $B):
   return %2 : $B
 }
 
+// CHECK-LABEL: sil @mark_dependence_trivial_address_base :
+// CHECK: bb0(
+// CHECK-NEXT: strong_retain
+// CHECK-NEXT: alloc_stack $Int
+// CHECK-NEXT: dealloc_stack
+// CHECK-NEXT: return
+// CHECK: } // end sil function 'mark_dependence_trivial_address_base'
+sil @mark_dependence_trivial_address_base : $@convention(thin) (@guaranteed B) -> @owned B {
+bb0(%0 : $B):
+  strong_retain %0 : $B
+  %1 = alloc_stack $Int
+  %2 = mark_dependence %0 : $B on %1 : $*Int
+  dealloc_stack %1 : $*Int
+  return %2 : $B
+}
+
 protocol _NSArrayCore {}
 
 // CHECK-LABEL: sil @mark_dependence_base2