Add SILArgument::getTerminatorForResultArg().

Author: atrick

include/swift/SIL/SILArgument.h

@@ -181,6 +181,10 @@ class SILArgument : public ValueBase {
   /// terminator has a single operand, return that terminator.
   TermInst *getSingleTerminator() const;
 
+  /// Return the terminator instruction for which this argument is a result,
+  /// otherwise return nullptr.
+  TermInst *getTerminatorForResultArg() const;
+
   /// Return the SILArgumentKind of this argument.
   SILArgumentKind getKind() const {
     return SILArgumentKind(ValueBase::getKind());
@@ -289,9 +293,9 @@ class SILPhiArgument : public SILArgument {
   /// terminator has a single operand, return that terminator.
   TermInst *getSingleTerminator() const;
 
-  /// Return the terminator instruction of which this argument is a result or
-  /// nullptr.
-  TermInst *getTransformingTerminator() const;
+  /// Return the terminator instruction for which this argument is a result,
+  /// otherwise return nullptr.
+  TermInst *getTerminatorForResultArg() const;
 
   static bool classof(const SILInstruction *) = delete;
   static bool classof(const SILUndef *) = delete;
@@ -437,6 +441,16 @@ inline TermInst *SILArgument::getSingleTerminator() const {
   llvm_unreachable("Covered switch is not covered?!");
 }
 
+inline TermInst *SILArgument::getTerminatorForResultArg() const {
+  switch (getKind()) {
+  case SILArgumentKind::SILPhiArgument:
+    return cast<SILPhiArgument>(this)->getTerminatorForResultArg();
+  case SILArgumentKind::SILFunctionArgument:
+    return nullptr;
+  }
+  llvm_unreachable("Covered switch is not covered?!");
+}
+
 inline bool SILArgument::getIncomingPhiOperands(
     SmallVectorImpl<Operand *> &returnedPhiOperands) const {
   switch (getKind()) {

lib/SIL/IR/SILArgument.cpp

@@ -316,7 +316,7 @@ TermInst *SILPhiArgument::getSingleTerminator() const {
   return const_cast<SILBasicBlock *>(predBlock)->getTerminator();
 }
 
-TermInst *getTransformingTerminator() const {
+TermInst *SILPhiArgument::getTerminatorForResultArg() const {
   if (auto *termInst = getSingleTerminator()) {
     if (!isa<BranchInst>(termInst) && !isa<CondBranchInst>(termInst))
       return termInst;