Add suppport for ConstantExprs of shufflevectors whose result type is not equal to the

type of the vectors being shuffled.

llvm-svn: 64401

2 files changed, 23 insertions, 2 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index adffe829202..2ddfbe3a13c 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -933,7 +933,7 @@ bool BitcodeReader::ParseConstants() {
     case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
       const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
       if (Record.size() < 3 || OpTy == 0)
-        return Error("Invalid CE_INSERTELT record");
+        return Error("Invalid CE_SHUFFLEVEC record");
       Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
       Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
       const Type *ShufTy=VectorType::get(Type::Int32Ty, OpTy->getNumElements());
@@ -941,6 +941,18 @@ bool BitcodeReader::ParseConstants() {
       V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
       break;
     }
+    case bitc::CST_CODE_CE_SHUFVEC_EX: { // [opty, opval, opval, opval]
+      const VectorType *RTy = dyn_cast<VectorType>(CurTy);
+      const VectorType *OpTy = dyn_cast<VectorType>(getTypeByID(Record[0]));
+      if (Record.size() < 4 || RTy == 0 || OpTy == 0)
+        return Error("Invalid CE_SHUFVEC_EX record");
+      Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
+      Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
+      const Type *ShufTy=VectorType::get(Type::Int32Ty, RTy->getNumElements());
+      Constant *Op2 = ValueList.getConstantFwdRef(Record[3], ShufTy);
+      V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
+      break;
+    }
     case bitc::CST_CODE_CE_CMP: {     // CE_CMP: [opty, opval, opval, pred]
       if (Record.size() < 4) return Error("Invalid CE_CMP record");
       const Type *OpTy = getTypeByID(Record[0]);
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index e37c439f5ce..5633f0ffad9 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -643,7 +643,16 @@ static void WriteConstants(unsigned FirstVal, unsigned LastVal,
         Record.push_back(VE.getValueID(C->getOperand(2)));
         break;
       case Instruction::ShuffleVector:
-        Code = bitc::CST_CODE_CE_SHUFFLEVEC;
+        // If the return type and argument types are the same, this is a
+        // standard shufflevector instruction.  If the types are different,
+        // then the shuffle is widening or truncating the input vectors, and
+        // the argument type must also be encoded.
+        if (C->getType() == C->getOperand(0)->getType()) {
+          Code = bitc::CST_CODE_CE_SHUFFLEVEC;
+        } else {
+          Code = bitc::CST_CODE_CE_SHUFVEC_EX;
+          Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
+        }
         Record.push_back(VE.getValueID(C->getOperand(0)));
         Record.push_back(VE.getValueID(C->getOperand(1)));
         Record.push_back(VE.getValueID(C->getOperand(2)));