diff options
| -rw-r--r-- | llvm/include/llvm/CodeGen/SelectionDAGNodes.h | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/llvm/include/llvm/CodeGen/SelectionDAGNodes.h b/llvm/include/llvm/CodeGen/SelectionDAGNodes.h index fad77ae2389..a1dca4946b4 100644 --- a/llvm/include/llvm/CodeGen/SelectionDAGNodes.h +++ b/llvm/include/llvm/CodeGen/SelectionDAGNodes.h @@ -463,6 +463,7 @@ protected: }; union { + char RawSDNodeBits[sizeof(uint16_t)]; SDNodeBitfields SDNodeBits; ConstantSDNodeBitfields ConstantSDNodeBits; MemSDNodeBitfields MemSDNodeBits; @@ -471,6 +472,21 @@ protected: StoreSDNodeBitfields StoreSDNodeBits; }; + // RawSDNodeBits must cover the entirety of the union. This means that all + // of the union's members must have size <= RawSDNodeBits. + static_assert(sizeof(SDNodeBits) <= sizeof(RawSDNodeBits), + "SDNodeBits too wide"); + static_assert(sizeof(ConstantSDNodeBits) <= sizeof(RawSDNodeBits), + "ConstantSDNodeBits too wide"); + static_assert(sizeof(MemSDNodeBits) <= sizeof(RawSDNodeBits), + "MemSDNodeBits too wide"); + static_assert(sizeof(LSBaseSDNodeBits) <= sizeof(RawSDNodeBits), + "LSBaseSDNodeBits too wide"); + static_assert(sizeof(LoadSDNodeBits) <= sizeof(RawSDNodeBits), + "LoadSDNodeBits too wide"); + static_assert(sizeof(StoreSDNodeBits) <= sizeof(RawSDNodeBits), + "StoreSDNodeBits too wide"); + private: /// Unique id per SDNode in the DAG. int NodeId; @@ -876,7 +892,7 @@ protected: : NodeType(Opc), NodeId(-1), OperandList(nullptr), ValueList(VTs.VTs), UseList(nullptr), NumOperands(0), NumValues(VTs.NumVTs), IROrder(Order), debugLoc(std::move(dl)) { - memset(&SDNodeBits, 0, sizeof(SDNodeBits)); + memset(&RawSDNodeBits, 0, sizeof(RawSDNodeBits)); assert(debugLoc.hasTrivialDestructor() && "Expected trivial destructor"); assert(NumValues == VTs.NumVTs && "NumValues wasn't wide enough for its operands!"); @@ -1095,9 +1111,7 @@ public: /// function should only be used to compute a FoldingSetNodeID value. unsigned getRawSubclassData() const { uint16_t Data; - memcpy(&Data, &SDNodeBits, sizeof(SDNodeBits)); - static_assert(sizeof(SDNodeBits) <= sizeof(uint16_t), - "SDNodeBits field too large?"); + memcpy(&Data, &RawSDNodeBits, sizeof(RawSDNodeBits)); return Data; } |
