Revert r155682, "Use ConstantExpr::getExtractElement when constant-folding vectors"

It broke stage2 build. stage1/clang sometimes crashed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155699 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Analysis/ConstantFolding.cpp

@@ -788,10 +788,6 @@ Constant *llvm::ConstantFoldInstruction(Instruction *I,
       CommonValue = C;
     }
 
-    // Fold the PHI's operands.
-    if (ConstantExpr *NewCE = dyn_cast<ConstantExpr>(CommonValue))
-      CommonValue = ConstantFoldConstantExpression(NewCE, TD, TLI);
-
     // If we reach here, all incoming values are the same constant or undef.
     return CommonValue ? CommonValue : UndefValue::get(PN->getType());
   }
@@ -799,18 +795,12 @@ Constant *llvm::ConstantFoldInstruction(Instruction *I,
   // Scan the operand list, checking to see if they are all constants, if so,
   // hand off to ConstantFoldInstOperands.
   SmallVector<Constant*, 8> Ops;
-  for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i) {
-    Constant *Op = dyn_cast<Constant>(*i);
-    if (!Op)
+  for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i)
+    if (Constant *Op = dyn_cast<Constant>(*i))
+      Ops.push_back(Op);
+    else
       return 0;  // All operands not constant!
 
-    // Fold the Instruction's operands.
-    if (ConstantExpr *NewCE = dyn_cast<ConstantExpr>(Op))
-      Op = ConstantFoldConstantExpression(NewCE, TD, TLI);
-
-    Ops.push_back(Op);
-  }
-
   if (const CmpInst *CI = dyn_cast<CmpInst>(I))
     return ConstantFoldCompareInstOperands(CI->getPredicate(), Ops[0], Ops[1],
                                            TD, TLI);

lib/VMCore/ConstantFold.cpp

@@ -55,12 +55,13 @@ static Constant *BitCastConstantVector(Constant *CV, VectorType *DstTy) {
   
   Type *DstEltTy = DstTy->getElementType();
 
+  // Check to verify that all elements of the input are simple.
   SmallVector<Constant*, 16> Result;
-  Type *Ty = IntegerType::get(CV->getContext(), 32);
   for (unsigned i = 0; i != NumElts; ++i) {
-    Constant *C =
-      ConstantExpr::getExtractElement(CV, ConstantInt::get(Ty, i));
+    Constant *C = CV->getAggregateElement(i);
+    if (C == 0) return 0;
     C = ConstantExpr::getBitCast(C, DstEltTy);
+    if (isa<ConstantExpr>(C)) return 0;
     Result.push_back(C);
   }
 
@@ -552,12 +553,9 @@ Constant *llvm::ConstantFoldCastInstruction(unsigned opc, Constant *V,
     SmallVector<Constant*, 16> res;
     VectorType *DestVecTy = cast<VectorType>(DestTy);
     Type *DstEltTy = DestVecTy->getElementType();
-    Type *Ty = IntegerType::get(V->getContext(), 32);
-    for (unsigned i = 0, e = V->getType()->getVectorNumElements(); i != e; ++i) {
-      Constant *C =
-        ConstantExpr::getExtractElement(V, ConstantInt::get(Ty, i));
-      res.push_back(ConstantExpr::getCast(opc, C, DstEltTy));
-    }
+    for (unsigned i = 0, e = V->getType()->getVectorNumElements(); i != e; ++i)
+      res.push_back(ConstantExpr::getCast(opc,
+                                          V->getAggregateElement(i), DstEltTy));
     return ConstantVector::get(res);
   }
 
@@ -698,13 +696,12 @@ Constant *llvm::ConstantFoldSelectInstruction(Constant *Cond,
   // If the condition is a vector constant, fold the result elementwise.
   if (ConstantVector *CondV = dyn_cast<ConstantVector>(Cond)) {
     SmallVector<Constant*, 16> Result;
-    Type *Ty = IntegerType::get(CondV->getContext(), 32);
     for (unsigned i = 0, e = V1->getType()->getVectorNumElements(); i != e;++i){
       ConstantInt *Cond = dyn_cast<ConstantInt>(CondV->getOperand(i));
       if (Cond == 0) break;
       
-      Constant *V = Cond->isNullValue() ? V2 : V1;
-      Constant *Res = ConstantExpr::getExtractElement(V, ConstantInt::get(Ty, i));
+      Constant *Res = (Cond->getZExtValue() ? V1 : V2)->getAggregateElement(i);
+      if (Res == 0) break;
       Result.push_back(Res);
     }
     
@@ -763,16 +760,16 @@ Constant *llvm::ConstantFoldInsertElementInstruction(Constant *Val,
   const APInt &IdxVal = CIdx->getValue();
   
   SmallVector<Constant*, 16> Result;
-  Type *Ty = IntegerType::get(Val->getContext(), 32);
   for (unsigned i = 0, e = Val->getType()->getVectorNumElements(); i != e; ++i){
     if (i == IdxVal) {
       Result.push_back(Elt);
       continue;
     }
     
-    Constant *C =
-      ConstantExpr::getExtractElement(Val, ConstantInt::get(Ty, i));
-    Result.push_back(C);
+    if (Constant *C = Val->getAggregateElement(i))
+      Result.push_back(C);
+    else
+      return 0;
   }
   
   return ConstantVector::get(Result);
@@ -804,15 +801,11 @@ Constant *llvm::ConstantFoldShuffleVectorInstruction(Constant *V1,
     Constant *InElt;
     if (unsigned(Elt) >= SrcNumElts*2)
       InElt = UndefValue::get(EltTy);
-    else if (unsigned(Elt) >= SrcNumElts) {
-      Type *Ty = IntegerType::get(V2->getContext(), 32);
-      InElt =
-        ConstantExpr::getExtractElement(V2,
-                                        ConstantInt::get(Ty, Elt - SrcNumElts));
-    } else {
-      Type *Ty = IntegerType::get(V1->getContext(), 32);
-      InElt = ConstantExpr::getExtractElement(V1, ConstantInt::get(Ty, Elt));
-    }
+    else if (unsigned(Elt) >= SrcNumElts)
+      InElt = V2->getAggregateElement(Elt - SrcNumElts);
+    else
+      InElt = V1->getAggregateElement(Elt);
+    if (InElt == 0) return 0;
     Result.push_back(InElt);
   }
 
@@ -1137,17 +1130,16 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode,
   } else if (VectorType *VTy = dyn_cast<VectorType>(C1->getType())) {
     // Perform elementwise folding.
     SmallVector<Constant*, 16> Result;
-    Type *Ty = IntegerType::get(VTy->getContext(), 32);
     for (unsigned i = 0, e = VTy->getNumElements(); i != e; ++i) {
-      Constant *LHS =
-        ConstantExpr::getExtractElement(C1, ConstantInt::get(Ty, i));
-      Constant *RHS =
-        ConstantExpr::getExtractElement(C2, ConstantInt::get(Ty, i));
+      Constant *LHS = C1->getAggregateElement(i);
+      Constant *RHS = C2->getAggregateElement(i);
+      if (LHS == 0 || RHS == 0) break;
       
       Result.push_back(ConstantExpr::get(Opcode, LHS, RHS));
     }
     
-    return ConstantVector::get(Result);
+    if (Result.size() == VTy->getNumElements())
+      return ConstantVector::get(Result);
   }
 
   if (ConstantExpr *CE1 = dyn_cast<ConstantExpr>(C1)) {
@@ -1705,18 +1697,17 @@ Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred,
     // If we can constant fold the comparison of each element, constant fold
     // the whole vector comparison.
     SmallVector<Constant*, 4> ResElts;
-    Type *Ty = IntegerType::get(C1->getContext(), 32);
     // Compare the elements, producing an i1 result or constant expr.
     for (unsigned i = 0, e = C1->getType()->getVectorNumElements(); i != e;++i){
-      Constant *C1E =
-        ConstantExpr::getExtractElement(C1, ConstantInt::get(Ty, i));
-      Constant *C2E =
-        ConstantExpr::getExtractElement(C2, ConstantInt::get(Ty, i));
+      Constant *C1E = C1->getAggregateElement(i);
+      Constant *C2E = C2->getAggregateElement(i);
+      if (C1E == 0 || C2E == 0) break;
       
       ResElts.push_back(ConstantExpr::getCompare(pred, C1E, C2E));
     }
     
-    return ConstantVector::get(ResElts);
+    if (ResElts.size() == C1->getType()->getVectorNumElements())
+      return ConstantVector::get(ResElts);
   }
 
   if (C1->getType()->isFloatingPointTy()) {

test/Other/constant-fold-gep.ll

@@ -263,10 +263,10 @@ define i1* @hoo1() nounwind {
 ; OPT:   ret i64 ptrtoint (double* getelementptr ({ i1, double }* null, i64 0, i32 1) to i64)
 ; OPT: }
 ; OPT: define i64 @fc() nounwind {
-; OPT:   ret i64 mul (i64 ptrtoint (double* getelementptr (double* null, i32 1) to i64), i64 2)
+; OPT:   ret i64 mul nuw (i64 ptrtoint (double* getelementptr (double* null, i32 1) to i64), i64 2)
 ; OPT: }
 ; OPT: define i64 @fd() nounwind {
-; OPT:   ret i64 mul (i64 ptrtoint (double* getelementptr (double* null, i32 1) to i64), i64 11)
+; OPT:   ret i64 mul nuw (i64 ptrtoint (double* getelementptr (double* null, i32 1) to i64), i64 11)
 ; OPT: }
 ; OPT: define i64 @fe() nounwind {
 ; OPT:   ret i64 ptrtoint (double* getelementptr ({ double, float, double, double }* null, i64 0, i32 2) to i64)
@@ -433,7 +433,7 @@ define i64* @fO() nounwind {
 ; PLAIN:   ret i32* %t
 ; PLAIN: }
 ; OPT: define i32* @fZ() nounwind {
-; OPT:   ret i32* getelementptr (i32* getelementptr inbounds ([3 x { i32, i32 }]* @ext, i64 0, i64 1, i32 0), i64 1)
+; OPT:   ret i32* getelementptr inbounds (i32* getelementptr inbounds ([3 x { i32, i32 }]* @ext, i64 0, i64 1, i32 0), i64 1)
 ; OPT: }
 ; TO: define i32* @fZ() nounwind {
 ; TO:   ret i32* getelementptr inbounds ([3 x { i32, i32 }]* @ext, i64 0, i64 1, i32 1)

test/Transforms/SCCP/vector-bitcast.ll

@@ -1,20 +0,0 @@
-; RUN: opt -sccp -S < %s | FileCheck %s
-
-target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32-S128"
-
-; CHECK: store volatile <2 x i64> zeroinitializer, <2 x i64>* %p
-; rdar://11324230
-
-define void @foo(<2 x i64>* %p) nounwind {
-entry:
-  br label %while.body.i
-
-while.body.i:                                     ; preds = %while.body.i, %entry
-  %vWorkExponent.i.033 = phi <4 x i32> [ %sub.i.i, %while.body.i ], [ <i32 939524096, i32 939524096, i32 939524096, i32 939524096>, %entry ]
-  %sub.i.i = add <4 x i32> %vWorkExponent.i.033, <i32 -8388608, i32 -8388608, i32 -8388608, i32 -8388608>
-  %0 = bitcast <4 x i32> %sub.i.i to <2 x i64>
-  %and.i119.i = and <2 x i64> %0, zeroinitializer
-  store volatile <2 x i64> %and.i119.i, <2 x i64>* %p
-  br label %while.body.i
-}
-