[cast-opt] Change CheckedCastBranch metatype opts to use SILDynamicCastInst.

Author: gottesmm

include/swift/SIL/DynamicCasts.h

@@ -210,7 +210,9 @@ struct SILDynamicCastInst {
   SILBasicBlock *getSuccessBlock() {
     switch (getKind()) {
     case SILDynamicCastKind::CheckedCastAddrBranchInst:
+      llvm_unreachable("unsupported");
     case SILDynamicCastKind::CheckedCastBranchInst:
+      return cast<CheckedCastBranchInst>(inst)->getSuccessBB();
     case SILDynamicCastKind::CheckedCastValueBranchInst:
       llvm_unreachable("unsupported");
     case SILDynamicCastKind::UnconditionalCheckedCastAddrInst:
@@ -221,14 +223,32 @@ struct SILDynamicCastInst {
     }
   }
 
+  Optional<ProfileCounter> getSuccessBlockCount() {
+    switch (getKind()) {
+    case SILDynamicCastKind::CheckedCastAddrBranchInst:
+      llvm_unreachable("unsupported");
+    case SILDynamicCastKind::CheckedCastBranchInst:
+      return cast<CheckedCastBranchInst>(inst)->getTrueBBCount();
+    case SILDynamicCastKind::CheckedCastValueBranchInst:
+      llvm_unreachable("unsupported");
+    case SILDynamicCastKind::UnconditionalCheckedCastAddrInst:
+    case SILDynamicCastKind::UnconditionalCheckedCastInst:
+      return None;
+    case SILDynamicCastKind::UnconditionalCheckedCastValueInst:
+      llvm_unreachable("unsupported");
+    }
+  }
+
   const SILBasicBlock *getSuccessBlock() const {
     return const_cast<SILDynamicCastInst &>(*this).getSuccessBlock();
   }
 
   SILBasicBlock *getFailureBlock() {
     switch (getKind()) {
     case SILDynamicCastKind::CheckedCastAddrBranchInst:
+      llvm_unreachable("unsupported");
     case SILDynamicCastKind::CheckedCastBranchInst:
+      return cast<CheckedCastBranchInst>(inst)->getFailureBB();
     case SILDynamicCastKind::CheckedCastValueBranchInst:
       llvm_unreachable("unsupported");
     case SILDynamicCastKind::UnconditionalCheckedCastAddrInst:
@@ -239,14 +259,32 @@ struct SILDynamicCastInst {
     }
   }
 
+  Optional<ProfileCounter> getFailureBlockCount() {
+    switch (getKind()) {
+    case SILDynamicCastKind::CheckedCastAddrBranchInst:
+      llvm_unreachable("unsupported");
+    case SILDynamicCastKind::CheckedCastBranchInst:
+      return cast<CheckedCastBranchInst>(inst)->getFalseBBCount();
+    case SILDynamicCastKind::CheckedCastValueBranchInst:
+      llvm_unreachable("unsupported");
+    case SILDynamicCastKind::UnconditionalCheckedCastAddrInst:
+    case SILDynamicCastKind::UnconditionalCheckedCastInst:
+      return None;
+    case SILDynamicCastKind::UnconditionalCheckedCastValueInst:
+      llvm_unreachable("unsupported");
+    }
+  }
+
   const SILBasicBlock *getFailureBlock() const {
     return const_cast<SILDynamicCastInst &>(*this).getFailureBlock();
   }
 
   SILValue getSource() const {
     switch (getKind()) {
     case SILDynamicCastKind::CheckedCastAddrBranchInst:
+      llvm_unreachable("unsupported");
     case SILDynamicCastKind::CheckedCastBranchInst:
+      return cast<CheckedCastBranchInst>(inst)->getOperand();
     case SILDynamicCastKind::CheckedCastValueBranchInst:
       llvm_unreachable("unsupported");
     case SILDynamicCastKind::UnconditionalCheckedCastAddrInst:
@@ -327,7 +365,9 @@ struct SILDynamicCastInst {
   SILType getLoweredTargetType() const {
     switch (getKind()) {
     case SILDynamicCastKind::CheckedCastAddrBranchInst:
+      llvm_unreachable("unsupported");
     case SILDynamicCastKind::CheckedCastBranchInst:
+      return cast<CheckedCastBranchInst>(inst)->getCastType();
     case SILDynamicCastKind::CheckedCastValueBranchInst:
       llvm_unreachable("unsupported");
     case SILDynamicCastKind::UnconditionalCheckedCastAddrInst: {

lib/SILOptimizer/Utils/CastOptimizer.cpp

@@ -1098,11 +1098,21 @@ CastOptimizer::optimizeCheckedCastBranchInst(CheckedCastBranchInst *Inst) {
   if (Inst->isExact())
     return nullptr;
 
-  auto LoweredTargetType = Inst->getCastType();
-  auto Loc = Inst->getLoc();
-  auto *SuccessBB = Inst->getSuccessBB();
-  auto *FailureBB = Inst->getFailureBB();
-  auto Op = Inst->getOperand();
+  // Local helper we use to simplify replacing a checked_cast_branch with an
+  // optimized checked cast branch.
+  auto replaceCastHelper = [](SILBuilderWithScope &B,
+                              SILDynamicCastInst dynamicCast,
+                              MetatypeInst *mi) -> SILInstruction * {
+    return B.createCheckedCastBranch(
+        dynamicCast.getLocation(), false /*isExact*/, mi,
+        dynamicCast.getLoweredTargetType(), dynamicCast.getSuccessBlock(),
+        dynamicCast.getFailureBlock(), *dynamicCast.getSuccessBlockCount(),
+        *dynamicCast.getFailureBlockCount());
+  };
+
+  SILDynamicCastInst dynamicCast(Inst);
+
+  auto Op = dynamicCast.getSource();
 
   // Try to simplify checked_cond_br instructions using existential
   // metatypes by propagating a concrete type whenever it can be
@@ -1117,9 +1127,7 @@ CastOptimizer::optimizeCheckedCastBranchInst(CheckedCastBranchInst *Inst) {
   if (auto *IEMI = dyn_cast<InitExistentialMetatypeInst>(Op)) {
     if (auto *MI = dyn_cast<MetatypeInst>(IEMI->getOperand())) {
       SILBuilderWithScope B(Inst, BuilderContext);
-      auto *NewI = B.createCheckedCastBranch(
-          Loc, /* isExact */ false, MI, LoweredTargetType, SuccessBB, FailureBB,
-          Inst->getTrueBBCount(), Inst->getFalseBBCount());
+      auto *NewI = replaceCastHelper(B, dynamicCast, MI);
       EraseInstAction(Inst);
       return NewI;
     }
@@ -1183,10 +1191,7 @@ CastOptimizer::optimizeCheckedCastBranchInst(CheckedCastBranchInst *Inst) {
         B.getOpenedArchetypes().addOpenedArchetypeOperands(
             FoundIEI->getTypeDependentOperands());
         auto *MI = B.createMetatype(FoundIEI->getLoc(), SILMetaTy);
-
-        auto *NewI = B.createCheckedCastBranch(
-            Loc, /* isExact */ false, MI, LoweredTargetType, SuccessBB,
-            FailureBB, Inst->getTrueBBCount(), Inst->getFalseBBCount());
+        auto *NewI = replaceCastHelper(B, dynamicCast, MI);
         EraseInstAction(Inst);
         return NewI;
       }
@@ -1242,10 +1247,7 @@ CastOptimizer::optimizeCheckedCastBranchInst(CheckedCastBranchInst *Inst) {
         B.getOpenedArchetypes().addOpenedArchetypeOperands(
             FoundIERI->getTypeDependentOperands());
         auto *MI = B.createMetatype(FoundIERI->getLoc(), SILMetaTy);
-
-        auto *NewI = B.createCheckedCastBranch(
-            Loc, /* isExact */ false, MI, LoweredTargetType, SuccessBB,
-            FailureBB, Inst->getTrueBBCount(), Inst->getFalseBBCount());
+        auto *NewI = replaceCastHelper(B, dynamicCast, MI);
         EraseInstAction(Inst);
         return NewI;
       }