[move-only] Fix SILOptimizer code motion to preserve value deinits

Multiple code motion and ARC related passes were removing struct/enum
deinits.

Passes fixed include:
- SILCombine
- EarlyCodeMotion
- ReleaseHoisting
- *many* passes that rely on ARC analysis (RCIndentity)

lib/SILOptimizer/Transforms/SILCodeMotion.cpp

@@ -564,6 +564,10 @@ bool BBEnumTagDataflowState::visitReleaseValueInst(ReleaseValueInst *RVI) {
   if (FindResult == ValueToCaseMap.end())
     return false;
 
+  // If the enum has a deinit, preserve the original release.
+  if (hasValueDeinit(RVI->getOperand()))
+    return false;
+
   // If we do not have any argument, just delete the release value.
   if (!(*FindResult)->second->hasAssociatedValues()) {
     RVI->eraseFromParent();
@@ -621,6 +625,10 @@ bool BBEnumTagDataflowState::hoistDecrementsIntoSwitchRegions(
       continue;
     }
 
+    // If the enum has a deinit, preserve the original release.
+    if (hasValueDeinit(Op))
+      return false;
+
     auto &EnumBBCaseList = (*R)->second;
     // If we don't have an enum tag for each predecessor of this BB, bail since
     // we do not know how to handle that BB.
@@ -1508,6 +1516,10 @@ static bool tryToSinkRefCountAcrossSwitch(SwitchEnumInst *Switch,
       RCIA->getRCIdentityRoot(Switch->getOperand()))
     return false;
 
+  // If the enum has a deinit, preserve the original release.
+  assert(!hasValueDeinit(Ptr) &&
+         "enum with deinit is not RC-identical to its payload");
+
   // If S has a default case bail since the default case could represent
   // multiple cases.
   //
@@ -1578,6 +1590,10 @@ static bool tryToSinkRefCountAcrossSelectEnum(CondBranchInst *CondBr,
       RCIA->getRCIdentityRoot(SEI->getEnumOperand()))
     return false;
 
+  // If the enum has a deinit, preserve the original release.
+  assert(!hasValueDeinit(Ptr) &&
+         "enum with deinit is not RC-identical to its payload");
+
   // Work out which enum element is the true branch, and which is false.
   // If the enum only has 2 values and its tag isn't the true branch, then we
   // know the true branch must be the other tag.