Implement Constant::isAllOnesValue(). Fix ConstantFolding to use the new api.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138469 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Constant.h

@@ -52,6 +52,10 @@ public:
   /// getNullValue.
   bool isNullValue() const;
 
+  /// isAllOnesValue - Return true if this is the value that would be returned by
+  /// getAllOnesValue.
+  bool isAllOnesValue() const;
+
   /// isNegativeZeroValue - Return true if the value is what would be returned 
   /// by getZeroValueForNegation.
   bool isNegativeZeroValue() const;

include/llvm/Constants.h

@@ -170,7 +170,7 @@ public:
   /// to true.
   /// @returns true iff this constant's bits are all set to true.
   /// @brief Determine if the value is all ones.
-  bool isAllOnesValue() const { 
+  bool isMinusOne() const { 
     return Val.isAllOnesValue();
   }
 

lib/Analysis/ConstantFolding.cpp

@@ -45,16 +45,12 @@ using namespace llvm;
 /// ConstantExpr if unfoldable.
 static Constant *FoldBitCast(Constant *C, Type *DestTy,
                              const TargetData &TD) {
-  
-  ConstantVector *CV = dyn_cast<ConstantVector>(C);
-  IntegerType *IntVTy = dyn_cast<IntegerType>(DestTy);
-  // When casting vectors to scalar integers, catch the
-  // obvious splat cases.
-  if (IntVTy && CV) {
-    if (CV->isNullValue()) return ConstantInt::getNullValue(IntVTy);
-    if (CV->isAllOnesValue()) return ConstantInt::getAllOnesValue(IntVTy);
-  }
-  
+  // Catch the obvious splat cases.
+  if (C->isNullValue() && !DestTy->isX86_MMXTy())
+    return Constant::getNullValue(DestTy);
+  if (C->isAllOnesValue() && !DestTy->isX86_MMXTy())
+    return Constant::getAllOnesValue(DestTy);
+
   // The code below only handles casts to vectors currently.
   VectorType *DestVTy = dyn_cast<VectorType>(DestTy);
   if (DestVTy == 0)
@@ -68,6 +64,7 @@ static Constant *FoldBitCast(Constant *C, Type *DestTy,
   }
   
   // If this is a bitcast from constant vector -> vector, fold it.
+  ConstantVector *CV = dyn_cast<ConstantVector>(C);
   if (CV == 0)
     return ConstantExpr::getBitCast(C, DestTy);
   

lib/VMCore/Constants.cpp

@@ -62,6 +62,21 @@ bool Constant::isNullValue() const {
   return isa<ConstantAggregateZero>(this) || isa<ConstantPointerNull>(this);
 }
 
+bool Constant::isAllOnesValue() const {
+  // Check for -1 integers
+  if (const ConstantInt *CI = dyn_cast<ConstantInt>(this))
+    return CI->isMinusOne();
+
+  // Check for FP which are bitcasted from -1 integers
+  if (const ConstantFP *CFP = dyn_cast<ConstantFP>(this))
+    return CFP->getValueAPF().bitcastToAPInt().isAllOnesValue();
+
+  // Check for constant vectors
+  if (const ConstantVector *CV = dyn_cast<ConstantVector>(this))
+    return CV->isAllOnesValue();
+
+  return false;
+}
 // Constructor to create a '0' constant of arbitrary type...
 Constant *Constant::getNullValue(Type *Ty) {
   switch (Ty->getTypeID()) {
@@ -126,7 +141,7 @@ Constant *Constant::getAllOnesValue(Type *Ty) {
   SmallVector<Constant*, 16> Elts;
   VectorType *VTy = cast<VectorType>(Ty);
   Elts.resize(VTy->getNumElements(), getAllOnesValue(VTy->getElementType()));
-  assert(Elts[0] && "Not a vector integer type!");
+  assert(Elts[0] && "Invalid AllOnes value!");
   return cast<ConstantVector>(ConstantVector::get(Elts));
 }
 
@@ -1064,13 +1079,16 @@ bool ConstantVector::isAllOnesValue() const {
   // Check out first element.
   const Constant *Elt = getOperand(0);
   const ConstantInt *CI = dyn_cast<ConstantInt>(Elt);
-  if (!CI || !CI->isAllOnesValue()) return false;
+  const ConstantFP *CF = dyn_cast<ConstantFP>(Elt);
+
   // Then make sure all remaining elements point to the same value.
   for (unsigned I = 1, E = getNumOperands(); I < E; ++I)
     if (getOperand(I) != Elt)
       return false;
   
-  return true;
+  // First value is all-ones.
+  return (CI && CI->isAllOnesValue()) || 
+         (CF && CF->isAllOnesValue());
 }
 
 /// getSplatValue - If this is a splat constant, where all of the

test/Transforms/InstCombine/bitcast.ll

@@ -11,7 +11,7 @@ define i32 @test1(i64 %a) {
         %t3 = xor <2 x i32> %t1, %t2
         %t4 = extractelement <2 x i32> %t3, i32 0
         ret i32 %t4
-
+        
 ; CHECK: @test1
 ; CHECK: ret i32 0
 }
@@ -30,7 +30,7 @@ define float @test2(<2 x float> %A, <2 x i32> %B) {
 
   %add = fadd float %tmp24, %tmp4
   ret float %add
-
+  
 ; CHECK: @test2
 ; CHECK-NEXT:  %tmp24 = extractelement <2 x float> %A, i32 0
 ; CHECK-NEXT:  bitcast <2 x i32> %B to <2 x float>
@@ -55,7 +55,7 @@ define float @test3(<2 x float> %A, <2 x i64> %B) {
 
   %add = fadd float %tmp24, %tmp4
   ret float %add
-
+  
 ; CHECK: @test3
 ; CHECK-NEXT:  %tmp24 = extractelement <2 x float> %A, i32 1
 ; CHECK-NEXT:  bitcast <2 x i64> %B to <4 x float>
@@ -75,7 +75,7 @@ define <2 x i32> @test4(i32 %A, i32 %B){
   ; CHECK: @test4
   ; CHECK-NEXT: insertelement <2 x i32> undef, i32 %A, i32 0
   ; CHECK-NEXT: insertelement <2 x i32> {{.*}}, i32 %B, i32 1
-  ; CHECK-NEXT: ret <2 x i32>
+  ; CHECK-NEXT: ret <2 x i32> 
 
 }
 
@@ -92,7 +92,7 @@ define <2 x float> @test5(float %A, float %B) {
   ; CHECK: @test5
   ; CHECK-NEXT: insertelement <2 x float> undef, float %A, i32 0
   ; CHECK-NEXT: insertelement <2 x float> {{.*}}, float %B, i32 1
-  ; CHECK-NEXT: ret <2 x float>
+  ; CHECK-NEXT: ret <2 x float> 
 }
 
 define <2 x float> @test6(float %A){
@@ -113,3 +113,27 @@ define i64 @ISPC0(i64 %in) {
 ; CHECK: @ISPC0
 ; CHECK: ret i64 0
 }
+
+
+define i64 @Vec2(i64 %in) {
+  %out = and i64 %in, xor (i64 bitcast (<4 x i16> <i16 0, i16 0, i16 0, i16 0> to i64), i64 0)
+  ret i64 %out
+; CHECK: @Vec2
+; CHECK: ret i64 0
+}
+
+define i64 @All11(i64 %in) {
+  %out = and i64 %in, xor (i64 bitcast (<2 x float> bitcast (i64 -1 to <2 x float>) to i64), i64 -1) 
+  ret i64 %out
+; CHECK: @All11
+; CHECK: ret i64 0
+}
+
+
+define i32 @All111(i32 %in) {
+  %out = and i32 %in, xor (i32 bitcast (<1 x float> bitcast (i32 -1 to <1 x float>) to i32), i32 -1) 
+  ret i32 %out
+; CHECK: @All111
+; CHECK: ret i32 0
+}
+