Add a sys::OwningMemoryBlock class, which is a sys::MemoryBlock that owns its

underlying memory, and will automatically release it on destruction.

Use this to tidy up the orc::IndirectStubsInfo class.

llvm-svn: 251731

2 files changed, 40 insertions, 7 deletions

diff --git a/llvm/include/llvm/ExecutionEngine/Orc/OrcTargetSupport.h b/llvm/include/llvm/ExecutionEngine/Orc/OrcTargetSupport.h
index 2637ea593d5..58273ae4616 100644
--- a/llvm/include/llvm/ExecutionEngine/Orc/OrcTargetSupport.h
+++ b/llvm/include/llvm/ExecutionEngine/Orc/OrcTargetSupport.h
@@ -59,9 +59,16 @@ public:
     const static unsigned PtrSize = 8;
 
     IndirectStubsInfo() : NumStubs(0) {}
-    IndirectStubsInfo(IndirectStubsInfo&&);
-    IndirectStubsInfo& operator=(IndirectStubsInfo&&);
-    ~IndirectStubsInfo();
+    IndirectStubsInfo(IndirectStubsInfo &&Other)
+        : NumStubs(Other.NumStubs), StubsMem(std::move(Other.StubsMem)) {
+      Other.NumStubs = 0;
+    }
+    IndirectStubsInfo& operator=(IndirectStubsInfo &&Other) {
+      NumStubs = Other.NumStubs;
+      Other.NumStubs = 0;
+      StubsMem = std::move(Other.StubsMem);
+      return *this;
+    }
 
     /// @brief Number of stubs in this block.
     unsigned getNumStubs() const { return NumStubs; }
@@ -69,18 +76,19 @@ public:
     /// @brief Get a pointer to the stub at the given index, which must be in
     ///        the range 0 .. getNumStubs() - 1.
     void* getStub(unsigned Idx) const {
-      return static_cast<uint64_t*>(StubsBlock.base()) + Idx;
+      return static_cast<uint64_t*>(StubsMem.base()) + Idx;
     }
 
     /// @brief Get a pointer to the implementation-pointer at the given index,
     ///        which must be in the range 0 .. getNumStubs() - 1.
     void** getPtr(unsigned Idx) const {
-      return static_cast<void**>(PtrsBlock.base()) + Idx;
+      char *PtrsBase =
+        static_cast<char*>(StubsMem.base()) + NumStubs * StubSize;
+      return reinterpret_cast<void**>(PtrsBase) + Idx;
     }
   private:
     unsigned NumStubs;
-    sys::MemoryBlock StubsBlock;
-    sys::MemoryBlock PtrsBlock;
+    sys::OwningMemoryBlock StubsMem;
   };
 
   /// @brief Emit at least MinStubs worth of indirect call stubs, rounded out to
diff --git a/llvm/include/llvm/Support/Memory.h b/llvm/include/llvm/Support/Memory.h
index 47fd327e2e2..8103aea2fa2 100644
--- a/llvm/include/llvm/Support/Memory.h
+++ b/llvm/include/llvm/Support/Memory.h
@@ -155,6 +155,31 @@ namespace sys {
     /// as writable.
     static bool setRangeWritable(const void *Addr, size_t Size);
   };
+
+  /// Owning version of MemoryBlock.
+  class OwningMemoryBlock {
+  public:
+    OwningMemoryBlock() = default;
+    explicit OwningMemoryBlock(MemoryBlock M) : M(M) {}
+    OwningMemoryBlock(OwningMemoryBlock &&Other) {
+      M = Other.M;
+      Other.M = MemoryBlock();
+    }
+    OwningMemoryBlock& operator=(OwningMemoryBlock &&Other) {
+      M = Other.M;
+      Other.M = MemoryBlock();
+      return *this;
+    }
+    ~OwningMemoryBlock() {
+      Memory::releaseMappedMemory(M);
+    }
+    void *base() const { return M.base(); }
+    size_t size() const { return M.size(); }
+    MemoryBlock getMemoryBlock() const { return M; }
+  private:
+    MemoryBlock M;
+  };
+
 }
 }