IR: make getParamByValType Just Work. NFC.

Most parts of LLVM don't care whether the byval type is derived from an
explicit Attribute or from the parameter's pointee type, so it makes
sense for the main access function to just return the right value.

The very few users who do care (only BitcodeReader so far) can find out
how it's specified by accessing the Attribute directly.

llvm-svn: 362642

8 files changed, 24 insertions, 9 deletions

diff --git a/llvm/include/llvm/IR/Argument.h b/llvm/include/llvm/IR/Argument.h
index 952fbcdffb1..5f514b9c47d 100644
--- a/llvm/include/llvm/IR/Argument.h
+++ b/llvm/include/llvm/IR/Argument.h
@@ -124,6 +124,8 @@ public:
   /// Check if an argument has a given attribute.
   bool hasAttribute(Attribute::AttrKind Kind) const;
 
+  Attribute getAttribute(Attribute::AttrKind Kind) const;
+
   /// Method for support type inquiry through isa, cast, and dyn_cast.
   static bool classof(const Value *V) {
     return V->getValueID() == ArgumentVal;
diff --git a/llvm/include/llvm/IR/Function.h b/llvm/include/llvm/IR/Function.h
index 896c2189eb8..b93541cbb16 100644
--- a/llvm/include/llvm/IR/Function.h
+++ b/llvm/include/llvm/IR/Function.h
@@ -401,6 +401,11 @@ public:
     return getAttributes().hasParamAttribute(ArgNo, Kind);
   }
 
+  /// gets the specified attribute from the list of attributes.
+  Attribute getParamAttribute(unsigned ArgNo, Attribute::AttrKind Kind) const {
+    return getAttributes().getParamAttr(ArgNo, Kind);
+  }
+
   /// gets the attribute from the list of attributes.
   Attribute getAttribute(unsigned i, Attribute::AttrKind Kind) const {
     return AttributeSets.getAttribute(i, Kind);
@@ -431,9 +436,10 @@ public:
     return AttributeSets.getParamAlignment(ArgNo);
   }
 
-  /// Extract the byval type for a parameter (nullptr=unknown).
+  /// Extract the byval type for a parameter.
   Type *getParamByValType(unsigned ArgNo) const {
-    return AttributeSets.getParamByValType(ArgNo);
+    Type *Ty = AttributeSets.getParamByValType(ArgNo);
+    return Ty ? Ty : (arg_begin() + ArgNo)->getType()->getPointerElementType();
   }
 
   /// Extract the number of dereferenceable bytes for a call or
diff --git a/llvm/include/llvm/IR/InstrTypes.h b/llvm/include/llvm/IR/InstrTypes.h
index 6ce76811c0e..237929f5e60 100644
--- a/llvm/include/llvm/IR/InstrTypes.h
+++ b/llvm/include/llvm/IR/InstrTypes.h
@@ -1560,9 +1560,10 @@ public:
     return Attrs.getParamAlignment(ArgNo);
   }
 
-  /// Extract the byval type for a call or parameter (nullptr=unknown).
+  /// Extract the byval type for a call or parameter.
   Type *getParamByValType(unsigned ArgNo) const {
-    return Attrs.getParamByValType(ArgNo);
+    Type *Ty = Attrs.getParamByValType(ArgNo);
+    return Ty ? Ty : getArgOperand(ArgNo)->getType()->getPointerElementType();
   }
 
   /// Extract the number of dereferenceable bytes for a call or
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 9f562ba82db..c33fc568abe 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -3049,7 +3049,8 @@ Error BitcodeReader::parseFunctionRecord(ArrayRef<uint64_t> Record) {
   // pointee type. There should be no opaque pointers where the byval type is
   // implicit.
   for (auto &Arg : Func->args()) {
-    if (Arg.hasByValAttr() && !Arg.getParamByValType()) {
+    if (Arg.hasByValAttr() &&
+        !Arg.getAttribute(Attribute::ByVal).getValueAsType()) {
       Arg.removeAttr(Attribute::ByVal);
       Arg.addAttr(Attribute::getWithByValType(
           Context, Arg.getType()->getPointerElementType()));
diff --git a/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp b/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
index 143570fb20a..f59c906c7b7 100644
--- a/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
+++ b/llvm/lib/Bitcode/Writer/ValueEnumerator.cpp
@@ -951,7 +951,7 @@ void ValueEnumerator::incorporateFunction(const Function &F) {
   // Adding function arguments to the value table.
   for (const auto &I : F.args()) {
     EnumerateValue(&I);
-    if (I.hasAttribute(Attribute::ByVal) && I.getParamByValType())
+    if (I.hasAttribute(Attribute::ByVal))
       EnumerateType(I.getParamByValType());
   }
   FirstFuncConstantID = Values.size();
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 4f7257d4a15..07d6ac83e03 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -9584,8 +9584,7 @@ void SelectionDAGISel::LowerArguments(const Function &F) {
         // For ByVal, size and alignment should be passed from FE.  BE will
         // guess if this info is not there but there are cases it cannot get
         // right.
-        unsigned FrameSize = DL.getTypeAllocSize(
-            Arg.getParamByValType() ? Arg.getParamByValType() : ElementTy);
+        unsigned FrameSize = DL.getTypeAllocSize(Arg.getParamByValType());
         Flags.setByValSize(FrameSize);
 
         unsigned FrameAlign;
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 6e6917b39b6..c2123dbfdd9 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -112,7 +112,9 @@ void TargetLoweringBase::ArgListEntry::setAttributes(const CallBase *Call,
   IsSwiftSelf = Call->paramHasAttr(ArgIdx, Attribute::SwiftSelf);
   IsSwiftError = Call->paramHasAttr(ArgIdx, Attribute::SwiftError);
   Alignment = Call->getParamAlignment(ArgIdx);
-  ByValType = Call->getParamByValType(ArgIdx);
+  ByValType = nullptr;
+  if (Call->paramHasAttr(ArgIdx, Attribute::ByVal))
+    ByValType = Call->getParamByValType(ArgIdx);
 }
 
 /// Generate a libcall taking the given operands as arguments and returning a
diff --git a/llvm/lib/IR/Function.cpp b/llvm/lib/IR/Function.cpp
index a4a78ca4deb..c88fd1a82cd 100644
--- a/llvm/lib/IR/Function.cpp
+++ b/llvm/lib/IR/Function.cpp
@@ -194,6 +194,10 @@ bool Argument::hasAttribute(Attribute::AttrKind Kind) const {
   return getParent()->hasParamAttribute(getArgNo(), Kind);
 }
 
+Attribute Argument::getAttribute(Attribute::AttrKind Kind) const {
+  return getParent()->getParamAttribute(getArgNo(), Kind);
+}
+
 //===----------------------------------------------------------------------===//
 // Helper Methods in Function
 //===----------------------------------------------------------------------===//