Fix integer undefined behavior due to signed left shift overflow in LLVM.

Reviewed offline by chandlerc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162623 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 25 insertions, 10 deletions

diff --git a/include/llvm/ADT/BitVector.h b/include/llvm/ADT/BitVector.h
index 3e2e5f230a..df896b98f4 100644
--- a/include/llvm/ADT/BitVector.h
+++ b/include/llvm/ADT/BitVector.h
@@ -172,7 +172,7 @@ public:
     unsigned BitPos = Prev % BITWORD_SIZE;
     BitWord Copy = Bits[WordPos];
     // Mask off previous bits.
-    Copy &= ~0L << BitPos;
+    Copy &= ~0UL << BitPos;
 
     if (Copy != 0) {
       if (sizeof(BitWord) == 4)
@@ -451,8 +451,11 @@ private:
     //  Then set any stray high bits of the last used word.
     unsigned ExtraBits = Size % BITWORD_SIZE;
     if (ExtraBits) {
-      Bits[UsedWords-1] &= ~(~0L << ExtraBits);
-      Bits[UsedWords-1] |= (0 - (BitWord)t) << ExtraBits;
+      BitWord ExtraBitMask = ~0UL << ExtraBits;
+      if (t)
+        Bits[UsedWords-1] |= ExtraBitMask;
+      else
+        Bits[UsedWords-1] &= ~ExtraBitMask;
     }
   }
 
diff --git a/include/llvm/ADT/DenseMapInfo.h b/include/llvm/ADT/DenseMapInfo.h
index 1559a35c39..6f17a647b6 100644
--- a/include/llvm/ADT/DenseMapInfo.h
+++ b/include/llvm/ADT/DenseMapInfo.h
@@ -31,12 +31,12 @@ struct DenseMapInfo {
 template<typename T>
 struct DenseMapInfo<T*> {
   static inline T* getEmptyKey() {
-    intptr_t Val = -1;
+    uintptr_t Val = static_cast<uintptr_t>(-1);
     Val <<= PointerLikeTypeTraits<T*>::NumLowBitsAvailable;
     return reinterpret_cast<T*>(Val);
   }
   static inline T* getTombstoneKey() {
-    intptr_t Val = -2;
+    uintptr_t Val = static_cast<uintptr_t>(-2);
     Val <<= PointerLikeTypeTraits<T*>::NumLowBitsAvailable;
     return reinterpret_cast<T*>(Val);
   }
@@ -105,7 +105,7 @@ template<> struct DenseMapInfo<int> {
 // Provide DenseMapInfo for longs.
 template<> struct DenseMapInfo<long> {
   static inline long getEmptyKey() {
-    return (1UL << (sizeof(long) * 8 - 1)) - 1L;
+    return (1UL << (sizeof(long) * 8 - 1)) - 1UL;
   }
   static inline long getTombstoneKey() { return getEmptyKey() - 1L; }
   static unsigned getHashValue(const long& Val) {
diff --git a/include/llvm/ADT/PointerIntPair.h b/include/llvm/ADT/PointerIntPair.h
index fcc758b43a..71c379bad5 100644
--- a/include/llvm/ADT/PointerIntPair.h
+++ b/include/llvm/ADT/PointerIntPair.h
@@ -135,12 +135,12 @@ template<typename PointerTy, unsigned IntBits, typename IntType>
 struct DenseMapInfo<PointerIntPair<PointerTy, IntBits, IntType> > {
   typedef PointerIntPair<PointerTy, IntBits, IntType> Ty;
   static Ty getEmptyKey() {
-    intptr_t Val = -1;
+    uintptr_t Val = static_cast<uintptr_t>(-1);
     Val <<= PointerLikeTypeTraits<PointerTy>::NumLowBitsAvailable;
     return Ty(reinterpret_cast<PointerTy>(Val), IntType((1 << IntBits)-1));
   }
   static Ty getTombstoneKey() {
-    intptr_t Val = -2;
+    uintptr_t Val = static_cast<uintptr_t>(-2);
     Val <<= PointerLikeTypeTraits<PointerTy>::NumLowBitsAvailable;
     return Ty(reinterpret_cast<PointerTy>(Val), IntType(0));
   }
diff --git a/include/llvm/ADT/SparseBitVector.h b/include/llvm/ADT/SparseBitVector.h
index 89774c3f56..791f1082c2 100644
--- a/include/llvm/ADT/SparseBitVector.h
+++ b/include/llvm/ADT/SparseBitVector.h
@@ -158,7 +158,7 @@ public:
             && "Word Position outside of element");
 
     // Mask off previous bits.
-    Copy &= ~0L << BitPos;
+    Copy &= ~0UL << BitPos;
 
     if (Copy != 0) {
       if (sizeof(BitWord) == 4)
diff --git a/include/llvm/CodeGen/MachineOperand.h b/include/llvm/CodeGen/MachineOperand.h
index 37d42b3583..c09d9f1251 100644
--- a/include/llvm/CodeGen/MachineOperand.h
+++ b/include/llvm/CodeGen/MachineOperand.h
@@ -421,7 +421,7 @@ public:
   int64_t getOffset() const {
     assert((isGlobal() || isSymbol() || isCPI() || isTargetIndex() ||
             isBlockAddress()) && "Wrong MachineOperand accessor");
-    return (int64_t(Contents.OffsetedInfo.OffsetHi) << 32) |
+    return int64_t(uint64_t(Contents.OffsetedInfo.OffsetHi) << 32) |
            SmallContents.OffsetLo;
   }
 
diff --git a/include/llvm/Support/MathExtras.h b/include/llvm/Support/MathExtras.h
index 4005161320..35c2694cff 100644
--- a/include/llvm/Support/MathExtras.h
+++ b/include/llvm/Support/MathExtras.h
@@ -463,12 +463,24 @@ template <unsigned B> inline int32_t SignExtend32(uint32_t x) {
   return int32_t(x << (32 - B)) >> (32 - B);
 }
 
+/// \brief Sign extend number in the bottom B bits of X to a 32-bit int.
+/// Requires 0 < B <= 32.
+inline int32_t SignExtend32(uint32_t X, unsigned B) {
+  return int32_t(X << (32 - B)) >> (32 - B);
+}
+
 /// SignExtend64 - Sign extend B-bit number x to 64-bit int.
 /// Usage int64_t r = SignExtend64<5>(x);
 template <unsigned B> inline int64_t SignExtend64(uint64_t x) {
   return int64_t(x << (64 - B)) >> (64 - B);
 }
 
+/// \brief Sign extend number in the bottom B bits of X to a 64-bit int.
+/// Requires 0 < B <= 64.
+inline int64_t SignExtend64(uint64_t X, unsigned B) {
+  return int64_t(X << (64 - B)) >> (64 - B);
+}
+
 } // End llvm namespace
 
 #endif