diff options
Diffstat (limited to 'include/llvm/ADT/APInt.h')
| -rw-r--r-- | include/llvm/ADT/APInt.h | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/include/llvm/ADT/APInt.h b/include/llvm/ADT/APInt.h index aa3c3f6..f4e7e3c 100644 --- a/include/llvm/ADT/APInt.h +++ b/include/llvm/ADT/APInt.h @@ -656,13 +656,24 @@ public: /// @brief Move assignment operator. APInt &operator=(APInt &&that) { - if (!isSingleWord()) + if (!isSingleWord()) { + // The MSVC STL shipped in 2013 requires that self move assignment be a + // no-op. Otherwise algorithms like stable_sort will produce answers + // where half of the output is left in a moved-from state. + if (this == &that) + return *this; delete[] pVal; + } - BitWidth = that.BitWidth; - VAL = that.VAL; + // Use memcpy so that type based alias analysis sees both VAL and pVal + // as modified. + memcpy(&VAL, &that.VAL, sizeof(uint64_t)); + // If 'this == &that', avoid zeroing our own bitwidth by storing to 'that' + // first. + unsigned ThatBitWidth = that.BitWidth; that.BitWidth = 0; + BitWidth = ThatBitWidth; return *this; } @@ -936,7 +947,8 @@ public: APInt sdiv_ov(const APInt &RHS, bool &Overflow) const; APInt smul_ov(const APInt &RHS, bool &Overflow) const; APInt umul_ov(const APInt &RHS, bool &Overflow) const; - APInt sshl_ov(unsigned Amt, bool &Overflow) const; + APInt sshl_ov(const APInt &Amt, bool &Overflow) const; + APInt ushl_ov(const APInt &Amt, bool &Overflow) const; /// \brief Array-indexing support. /// |