Merge pull request #17188 from gottesmm/swift-4.2-branch-41102667

[arc-codemotion] Do not call virtual methods in constructors.

Author: gottesmm

lib/SILOptimizer/Transforms/ARCCodeMotion.cpp

@@ -242,6 +242,8 @@ class CodeMotionContext {
 };
 
 bool CodeMotionContext::run() {
+  MultiIteration = requireIteration();
+
   // Initialize the data flow.
   initializeCodeMotionDataFlow();
 
@@ -332,9 +334,7 @@ class RetainCodeMotionContext : public CodeMotionContext {
   RetainCodeMotionContext(llvm::SpecificBumpPtrAllocator<BlockState> &BPA,
                           SILFunction *F, PostOrderFunctionInfo *PO,
                           AliasAnalysis *AA, RCIdentityFunctionInfo *RCFI)
-    : CodeMotionContext(BPA, F, PO, AA, RCFI) {
-    MultiIteration = requireIteration();
-  }
+      : CodeMotionContext(BPA, F, PO, AA, RCFI) {}
 
   /// virtual destructor.
   ~RetainCodeMotionContext() override {}
@@ -684,10 +684,8 @@ class ReleaseCodeMotionContext : public CodeMotionContext {
                            AliasAnalysis *AA, RCIdentityFunctionInfo *RCFI,
                            bool FreezeEpilogueReleases,
                            ConsumedArgToEpilogueReleaseMatcher &ERM)
-    : CodeMotionContext(BPA, F, PO, AA, RCFI),
-      FreezeEpilogueReleases(FreezeEpilogueReleases), ERM(ERM) {
-    MultiIteration = requireIteration();
-  } 
+      : CodeMotionContext(BPA, F, PO, AA, RCFI),
+        FreezeEpilogueReleases(FreezeEpilogueReleases), ERM(ERM) {}
 
   /// virtual destructor.
   ~ReleaseCodeMotionContext() override {}