[SIL] Add source formal type to checked_cast_br.

SwiftCompilerSources/Sources/Optimizer/InstructionSimplification/SimplifyRefCasts.swift

@@ -36,13 +36,13 @@ private extension UnaryInstruction {
   /// ```
   ///   %2 = upcast %1 : $Derived to $Base
   ///   %3 = init_existential_ref %2 : $Base : $Base, $AnyObject
-  ///   checked_cast_br %3 : $AnyObject to Derived, bb1, bb2
+  ///   checked_cast_br AnyObject in %3 : $AnyObject to Derived, bb1, bb2
   /// ```
   ///
   /// This makes it more likely that the cast can be constant folded because the source
   /// operand's type is more accurate. In the example above, the cast reduces to
   /// ```
-  ///   checked_cast_br %1 : $Derived to Derived, bb1, bb2
+  ///   checked_cast_br Derived in %1 : $Derived to Derived, bb1, bb2
   /// ```
   /// which can be trivially folded to always-succeeds.
   ///
@@ -97,13 +97,13 @@ private extension UnaryInstruction {
 /// For example:
 /// ```
 ///   %inst = upcast %sourceValue : $Derived to $Base
-///   checked_cast_br %inst : $Base to Derived, success_block, failure_block
+///   checked_cast_br Base in %inst : $Base to Derived, success_block, failure_block
 ///   ...
 /// failure_block(%oldArg : $Base):
 /// ```
 /// is converted to:
 /// ```
-///   checked_cast_br %sourceValue : $Derived to Derived, success_block, failure_block
+///   checked_cast_br Derived in %sourceValue : $Derived to Derived, success_block, failure_block
 ///   ...
 /// failure_block(%newArg : $Derived):
 ///   %3 = upcast %newArg : $Derived to $Base

docs/SIL.rst

@@ -2082,7 +2082,7 @@ derived from the ARC object. As an example, consider the following Swift/SIL::
 
     // Consume '%1'. This means '%1' can no longer be used after this point. We
     // rebind '%1' in the destination blocks (bbYes, bbNo).
-    checked_cast_br %1 : $Klass to $OtherKlass, bbYes, bbNo
+    checked_cast_br Klass in %1 : $Klass to $OtherKlass, bbYes, bbNo
 
   bbYes(%2 : @owned $OtherKlass): // On success, the checked_cast_br forwards
                                   // '%1' into '%2' after casting to OtherKlass.
@@ -8097,9 +8097,9 @@ checked_cast_br
                       sil-identifier ',' sil-identifier
   sil-checked-cast-exact ::= '[' 'exact' ']'
 
-  checked_cast_br %0 : $A to $B, bb1, bb2
-  checked_cast_br %0 : $*A to $*B, bb1, bb2
-  checked_cast_br [exact] %0 : $A to $A, bb1, bb2
+  checked_cast_br A in %0 : $A to $B, bb1, bb2
+  checked_cast_br *A in %0 : $*A to $*B, bb1, bb2
+  checked_cast_br [exact] A in %0 : $A to $A, bb1, bb2
   // $A and $B must be both object types or both address types
   // bb1 must take a single argument of type $B or $*B
   // bb2 must take no arguments

include/swift/SIL/SILBuilder.h

@@ -2575,17 +2575,18 @@ class SILBuilder {
   }
 
   CheckedCastBranchInst *
-  createCheckedCastBranch(SILLocation Loc, bool isExact, SILValue op,
-                          SILType destLoweredTy, CanType destFormalTy,
-                          SILBasicBlock *successBB,
+  createCheckedCastBranch(SILLocation Loc, bool isExact, SILValue op, 
+                          CanType srcFormalTy, SILType destLoweredTy, 
+                          CanType destFormalTy, SILBasicBlock *successBB,
                           SILBasicBlock *failureBB,
                           ProfileCounter Target1Count = ProfileCounter(),
                           ProfileCounter Target2Count = ProfileCounter());
 
   CheckedCastBranchInst *
-  createCheckedCastBranch(SILLocation Loc, bool isExact, SILValue op,
-                          SILType destLoweredTy, CanType destFormalTy,
-                          SILBasicBlock *successBB, SILBasicBlock *failureBB,
+  createCheckedCastBranch(SILLocation Loc, bool isExact, SILValue op, 
+                          CanType srcFormalTy, SILType destLoweredTy, 
+                          CanType destFormalTy, SILBasicBlock *successBB, 
+                          SILBasicBlock *failureBB,
                           ValueOwnershipKind forwardingOwnershipKind,
                           ProfileCounter Target1Count = ProfileCounter(),
                           ProfileCounter Target2Count = ProfileCounter());

include/swift/SIL/SILCloner.h

@@ -3128,6 +3128,7 @@ SILCloner<ImplClass>::visitCheckedCastBranchInst(CheckedCastBranchInst *Inst) {
       Inst, getBuilder().createCheckedCastBranch(
                 getOpLocation(Inst->getLoc()), Inst->isExact(),
                 getOpValue(Inst->getOperand()),
+                getOpASTType(Inst->getSourceFormalType()),
                 getOpType(Inst->getTargetLoweredType()),
                 getOpASTType(Inst->getTargetFormalType()), OpSuccBB, OpFailBB,
                 Inst->getForwardingOwnershipKind(), TrueCount, FalseCount));

include/swift/SIL/SILInstruction.h

@@ -10024,12 +10024,13 @@ class CheckedCastBranchInst final
           CastBranchInstBase<OwnershipForwardingTermInst>> {
   friend SILBuilder;
 
+  CanType SrcFormalTy;
   SILType DestLoweredTy;
   CanType DestFormalTy;
   bool IsExact;
 
   CheckedCastBranchInst(SILDebugLocation DebugLoc, bool IsExact,
-                        SILValue Operand,
+                        SILValue Operand, CanType SrcFormalTy,
                         ArrayRef<SILValue> TypeDependentOperands,
                         SILType DestLoweredTy, CanType DestFormalTy,
                         SILBasicBlock *SuccessBB, SILBasicBlock *FailureBB,
@@ -10041,21 +10042,21 @@ class CheckedCastBranchInst final
             DebugLoc, Operand, TypeDependentOperands, SuccessBB, FailureBB,
             Target1Count, Target2Count, forwardingOwnershipKind,
             preservesOwnership),
-        DestLoweredTy(DestLoweredTy), DestFormalTy(DestFormalTy),
-        IsExact(IsExact) {}
+        SrcFormalTy(SrcFormalTy), DestLoweredTy(DestLoweredTy),
+        DestFormalTy(DestFormalTy), IsExact(IsExact) {}
 
   static CheckedCastBranchInst *
   create(SILDebugLocation DebugLoc, bool IsExact, SILValue Operand,
-         SILType DestLoweredTy, CanType DestFormalTy, SILBasicBlock *SuccessBB,
-         SILBasicBlock *FailureBB, SILFunction &F,
+         CanType SrcFormalTy, SILType DestLoweredTy, CanType DestFormalTy,
+         SILBasicBlock *SuccessBB, SILBasicBlock *FailureBB, SILFunction &F,
          ProfileCounter Target1Count, ProfileCounter Target2Count,
          ValueOwnershipKind forwardingOwnershipKind);
 
 public:
   bool isExact() const { return IsExact; }
 
   SILType getSourceLoweredType() const { return getOperand()->getType(); }
-  CanType getSourceFormalType() const { return getSourceLoweredType().getASTType(); }
+  CanType getSourceFormalType() const { return SrcFormalTy; }
 
   SILType getTargetLoweredType() const { return DestLoweredTy; }
   CanType getTargetFormalType() const { return DestFormalTy; }

lib/IRGen/GenCast.cpp

@@ -125,7 +125,7 @@ FailableCastResult irgen::emitClassIdenticalCast(IRGenFunction &IGF,
   // of the metatype value to the subclass's static metatype instance.
   //
   // %1 = value_metatype $Super.Type, %0 : $A
-  // checked_cast_br [exact] %1 : $Super.Type to $Sub.Type
+  // checked_cast_br [exact] Super.Type in %1 : $Super.Type to $Sub.Type
   // =>
   // icmp eq %1, @metadata.Sub
   llvm::Value *objectMetadata = isMetatype ? from :
@@ -883,6 +883,7 @@ void irgen::emitScalarCheckedCast(IRGenFunction &IGF,
 
   bool sourceWrappedInOptional = false;
 
+  llvm::Optional<ConditionalDominanceScope> domScope;
   if (auto sourceOptObjectType = sourceLoweredType.getOptionalObjectType()) {
     // Translate the value from an enum representation to a possibly-null
     // representation.  Note that we assume that this projection is safe
@@ -912,6 +913,7 @@ void irgen::emitScalarCheckedCast(IRGenFunction &IGF,
       Builder.CreateCondBr(isNotNil, isNotNilContBB, nilMergeBB);
 
       Builder.emitBlock(isNotNilContBB);
+      domScope.emplace(IGF);
     }
   }
 

lib/SIL/IR/SILBuilder.cpp

@@ -675,7 +675,7 @@ void SILBuilder::emitScopedBorrowOperation(SILLocation loc, SILValue original,
 /// Example:
 ///
 ///     %mt = metatype $@thick C.Type
-///     checked_cast_br %mt : $@thick C.Type to AnyObject.Type, bb1, bb2,
+///     checked_cast_br C.Type in %mt : $@thick C.Type to AnyObject.Type, bb1, bb2,
 ///                           forwarding: @owned
 ///   bb1(%arg : @owned AnyObject.Type):
 ///
@@ -717,30 +717,30 @@ SwitchEnumInst *SILBuilder::createSwitchEnum(
 }
 
 CheckedCastBranchInst *SILBuilder::createCheckedCastBranch(
-    SILLocation Loc, bool isExact, SILValue op,
-    SILType destLoweredTy, CanType destFormalTy,
-    SILBasicBlock *successBB, SILBasicBlock *failureBB,
-    ProfileCounter target1Count, ProfileCounter target2Count) {
+    SILLocation Loc, bool isExact, SILValue op, CanType srcFormalTy,
+    SILType destLoweredTy, CanType destFormalTy, SILBasicBlock *successBB,
+    SILBasicBlock *failureBB, ProfileCounter target1Count,
+    ProfileCounter target2Count) {
   auto forwardingOwnership =
       deriveForwardingOwnership(op, destLoweredTy, getFunction());
-  return createCheckedCastBranch(Loc, isExact, op, destLoweredTy, destFormalTy,
-                                 successBB, failureBB, forwardingOwnership,
-                                 target1Count, target2Count);
+  return createCheckedCastBranch(
+      Loc, isExact, op, srcFormalTy, destLoweredTy, destFormalTy, successBB,
+      failureBB, forwardingOwnership, target1Count, target2Count);
 }
 
 CheckedCastBranchInst *SILBuilder::createCheckedCastBranch(
-    SILLocation Loc, bool isExact, SILValue op, SILType destLoweredTy,
-    CanType destFormalTy, SILBasicBlock *successBB, SILBasicBlock *failureBB,
-    ValueOwnershipKind forwardingOwnershipKind, ProfileCounter target1Count,
-    ProfileCounter target2Count) {
+    SILLocation Loc, bool isExact, SILValue op, CanType srcFormalTy,
+    SILType destLoweredTy, CanType destFormalTy, SILBasicBlock *successBB,
+    SILBasicBlock *failureBB, ValueOwnershipKind forwardingOwnershipKind,
+    ProfileCounter target1Count, ProfileCounter target2Count) {
   assert((!hasOwnership() || !failureBB->getNumArguments() ||
           failureBB->getArgument(0)->getType() == op->getType()) &&
          "failureBB's argument doesn't match incoming argument type");
 
   return insertTerminator(CheckedCastBranchInst::create(
-      getSILDebugLocation(Loc), isExact, op, destLoweredTy, destFormalTy,
-      successBB, failureBB, getFunction(), target1Count, target2Count,
-      forwardingOwnershipKind));
+      getSILDebugLocation(Loc), isExact, op, srcFormalTy, destLoweredTy,
+      destFormalTy, successBB, failureBB, getFunction(), target1Count,
+      target2Count, forwardingOwnershipKind));
 }
 
 void SILBuilderWithScope::insertAfter(SILInstruction *inst,

lib/SIL/IR/SILInstructions.cpp

@@ -2551,8 +2551,8 @@ UnconditionalCheckedCastInst *UnconditionalCheckedCastInst::create(
 
 CheckedCastBranchInst *CheckedCastBranchInst::create(
     SILDebugLocation DebugLoc, bool IsExact, SILValue Operand,
-    SILType DestLoweredTy, CanType DestFormalTy, SILBasicBlock *SuccessBB,
-    SILBasicBlock *FailureBB, SILFunction &F,
+    CanType SrcFormalTy, SILType DestLoweredTy, CanType DestFormalTy,
+    SILBasicBlock *SuccessBB, SILBasicBlock *FailureBB, SILFunction &F,
     ProfileCounter Target1Count, ProfileCounter Target2Count,
     ValueOwnershipKind forwardingOwnershipKind) {
   SILModule &module = F.getModule();
@@ -2561,12 +2561,12 @@ CheckedCastBranchInst *CheckedCastBranchInst::create(
   SmallVector<SILValue, 8> TypeDependentOperands;
   collectTypeDependentOperands(TypeDependentOperands, F, DestFormalTy);
   unsigned size =
-      totalSizeToAlloc<swift::Operand>(1 + TypeDependentOperands.size());
+      totalSizeToAlloc<swift::Operand>(3 + TypeDependentOperands.size());
   void *Buffer = module.allocateInst(size, alignof(CheckedCastBranchInst));
   return ::new (Buffer) CheckedCastBranchInst(
-      DebugLoc, IsExact, Operand, TypeDependentOperands, DestLoweredTy,
-      DestFormalTy, SuccessBB, FailureBB, Target1Count, Target2Count,
-      forwardingOwnershipKind, preservesOwnership);
+      DebugLoc, IsExact, Operand, SrcFormalTy, TypeDependentOperands,
+      DestLoweredTy, DestFormalTy, SuccessBB, FailureBB, Target1Count,
+      Target2Count, forwardingOwnershipKind, preservesOwnership);
 }
 
 MetatypeInst *MetatypeInst::create(SILDebugLocation Loc, SILType Ty,

lib/SIL/IR/SILPrinter.cpp

@@ -1914,6 +1914,7 @@ class SILPrinter : public SILInstructionVisitor<SILPrinter> {
   void visitCheckedCastBranchInst(CheckedCastBranchInst *CI) {
     if (CI->isExact())
       *this << "[exact] ";
+    *this << CI->getSourceFormalType() << " in ";
     *this << getIDAndType(CI->getOperand()) << " to " << CI->getTargetFormalType()
           << ", " << Ctx.getID(CI->getSuccessBB()) << ", "
           << Ctx.getID(CI->getFailureBB());

lib/SIL/Parser/ParseSIL.cpp

@@ -4489,6 +4489,9 @@ bool SILParser::parseSpecificSILInstruction(SILBuilder &B,
         parseSILOptional(isExact, *this, "exact"))
       return true;
 
+    if (parseASTType(SourceType) || parseVerbatim("in"))
+      return true;
+
     if (parseTypedValueRef(Val, B) || parseVerbatim("to") ||
         parseASTType(TargetType) || parseConditionalBranchDestinations())
       return true;
@@ -4501,8 +4504,9 @@ bool SILParser::parseSpecificSILInstruction(SILBuilder &B,
 
     auto opaque = Lowering::AbstractionPattern::getOpaque();
     ResultVal = B.createCheckedCastBranch(
-        InstLoc, isExact, Val, F->getLoweredType(opaque, TargetType),
-        TargetType, getBBForReference(SuccessBBName, SuccessBBLoc),
+        InstLoc, isExact, Val, SourceType,
+        F->getLoweredType(opaque, TargetType), TargetType,
+        getBBForReference(SuccessBBName, SuccessBBLoc),
         getBBForReference(FailureBBName, FailureBBLoc), forwardingOwnership);
     break;
   }

lib/SIL/Utils/DynamicCasts.cpp

@@ -1417,8 +1417,8 @@ void swift::emitIndirectConditionalCastWithScalar(
   })();
 
   auto *ccb = B.createCheckedCastBranch(
-      loc, /*exact*/ false, srcValue, targetLoweredType, targetFormalType,
-      scalarSuccBB, scalarFailBB, TrueCount, FalseCount);
+      loc, /*exact*/ false, srcValue, sourceFormalType, targetLoweredType,
+      targetFormalType, scalarSuccBB, scalarFailBB, TrueCount, FalseCount);
 
   // Emit the success block.
   B.setInsertionPoint(scalarSuccBB); {

lib/SILGen/SILGenBuilder.cpp

@@ -600,6 +600,7 @@ ManagedValue SILGenBuilder::createUnconditionalCheckedCast(
 
 void SILGenBuilder::createCheckedCastBranch(SILLocation loc, bool isExact,
                                             ManagedValue op,
+                                            CanType sourceFormalTy,
                                             SILType destLoweredTy,
                                             CanType destFormalTy,
                                             SILBasicBlock *trueBlock,
@@ -611,9 +612,8 @@ void SILGenBuilder::createCheckedCastBranch(SILLocation loc, bool isExact,
                                          destFormalTy)) {
     op = op.ensurePlusOne(SGF, loc);
   }
-  createCheckedCastBranch(loc, isExact, op.forward(SGF),
-                          destLoweredTy, destFormalTy,
-                          trueBlock, falseBlock,
+  createCheckedCastBranch(loc, isExact, op.forward(SGF), sourceFormalTy,
+                          destLoweredTy, destFormalTy, trueBlock, falseBlock,
                           Target1Count, Target2Count);
 }
 

lib/SILGen/SILGenBuilder.h

@@ -289,6 +289,7 @@ class SILGenBuilder : public SILBuilder {
   using SILBuilder::createCheckedCastBranch;
   void createCheckedCastBranch(SILLocation loc, bool isExact,
                                ManagedValue op,
+                               CanType sourceFormalTy,
                                SILType destLoweredTy,
                                CanType destFormalTy,
                                SILBasicBlock *trueBlock,

lib/SILGen/SILGenDynamicCast.cpp

@@ -150,8 +150,9 @@ namespace {
           operandValue = operandValue.borrow(SGF, Loc);
         }
         SGF.B.createCheckedCastBranch(Loc, /*exact*/ false, operandValue,
-                                      origTargetTL.getLoweredType(), TargetType,
-                                      trueBB, falseBB, TrueCount, FalseCount);
+                                      SourceType, origTargetTL.getLoweredType(),
+                                      TargetType, trueBB, falseBB, TrueCount,
+                                      FalseCount);
       }
 
       // Emit the success block.

lib/SILOptimizer/Differentiation/VJPCloner.cpp

@@ -370,6 +370,7 @@ class VJPCloner::Implementation final
     // Create a new `checked_cast_branch` instruction.
     getBuilder().createCheckedCastBranch(
         ccbi->getLoc(), ccbi->isExact(), getOpValue(ccbi->getOperand()),
+        getOpASTType(ccbi->getSourceFormalType()),
         getOpType(ccbi->getTargetLoweredType()),
         getOpASTType(ccbi->getTargetFormalType()),
         createTrampolineBasicBlock(ccbi, pbTupleVal, ccbi->getSuccessBB()),

lib/SILOptimizer/Transforms/SILCodeMotion.cpp

@@ -956,7 +956,7 @@ enum OperandRelation {
 ///
 /// bb1:
 ///  %3 = unchecked_enum_data %0 : $Optional<X>, #Optional.Some!enumelt
-///  checked_cast_br [exact] %3 : $X to $X, bb4, bb5 // id: %4
+///  checked_cast_br [exact] X in %3 : $X to $X, bb4, bb5 // id: %4
 ///
 /// bb4(%10 : $X):                                    // Preds: bb1
 ///  strong_release %10 : $X

lib/SILOptimizer/Transforms/SpeculativeDevirtualizer.cpp

@@ -162,7 +162,8 @@ static FullApplySite speculateMonomorphicTarget(FullApplySite AI,
   // class instance is identical to the SILType.
 
   CCBI = Builder.createCheckedCastBranch(AI.getLoc(), /*exact*/ true,
-                                      CMI->getOperand(),
+                                      CMI->getOperand(), 
+                                      CMI->getOperand()->getType().getASTType(),
                                       SILType::getPrimitiveObjectType(SubType),
                                       SubType, Iden, Virt);
   It = CCBI->getIterator();

lib/SILOptimizer/Utils/CastOptimizer.cpp

@@ -142,7 +142,9 @@ convertObjectToLoadableBridgeableType(SILBuilderWithScope &builder,
 
   // Ok, we need to perform the full cast optimization. This means that we are
   // going to replace the cast terminator in inst_block with a checked_cast_br.
-  auto *ccbi = builder.createCheckedCastBranch(loc, false, load, silBridgedTy,
+  auto *ccbi = builder.createCheckedCastBranch(loc, false, load, 
+                                               dynamicCast.getBridgedSourceType(), 
+                                               silBridgedTy,
                                                dynamicCast.getBridgedTargetType(),
                                                castSuccessBB, castFailBB);
   splitEdge(ccbi, /* EdgeIdx to CastFailBB */ 1);
@@ -538,6 +540,7 @@ static SILValue computeFinalCastedValue(SILBuilderWithScope &builder,
   auto loc = dynamicCast.getLocation();
   auto convTy = newAI->getType();
   bool isConditional = dynamicCast.isConditional();
+  auto sourceFormalTy = dynamicCast.getSourceFormalType();
   auto destLoweredTy = dynamicCast.getTargetLoweredType().getObjectType();
   auto destFormalTy = dynamicCast.getTargetFormalType();
   assert(destLoweredTy == dynamicCast.getLoweredBridgedTargetObjectType() &&
@@ -581,7 +584,7 @@ static SILValue computeFinalCastedValue(SILBuilderWithScope &builder,
         newAI->getFunction()->createBasicBlockAfter(newAI->getParent());
     condBrSuccessBB->createPhiArgument(destLoweredTy, OwnershipKind::Owned);
     builder.createCheckedCastBranch(loc, /* isExact*/ false, newAI,
-                                    destLoweredTy, destFormalTy,
+                                    sourceFormalTy, destLoweredTy, destFormalTy,
                                     condBrSuccessBB, failureBB);
     builder.setInsertionPoint(condBrSuccessBB, condBrSuccessBB->begin());
     return condBrSuccessBB->getArgument(0);
@@ -1151,6 +1154,7 @@ SILInstruction *CastOptimizer::optimizeCheckedCastAddrBranchInst(
           SILBuilderWithScope B(Inst, builderContext);
           auto NewI = B.createCheckedCastBranch(
               Loc, false /*isExact*/, MI,
+              Inst->getSourceFormalType(),
               Inst->getTargetLoweredType().getObjectType(),
               Inst->getTargetFormalType(),
               SuccessBB, FailureBB, Inst->getTrueBBCount(),
@@ -1193,6 +1197,9 @@ CastOptimizer::optimizeCheckedCastBranchInst(CheckedCastBranchInst *Inst) {
     }
     return B.createCheckedCastBranch(
         dynamicCast.getLocation(), false /*isExact*/, mi,
+        // The cast is now from the the MetatypeInst, so get the source formal
+        // type from it.
+        mi->getType().getASTType(),
         dynamicCast.getTargetLoweredType(),
         dynamicCast.getTargetFormalType(),
         dynamicCast.getSuccessBlock(),