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+//===-- SafeStackLayout.h - SafeStack frame layout -------------*- C++ -*--===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_CODEGEN_SAFESTACKLAYOUT_H
+#define LLVM_LIB_CODEGEN_SAFESTACKLAYOUT_H
+
+#include "SafeStackColoring.h"
+
+namespace llvm {
+namespace safestack {
+
+/// Compute the layout of an unsafe stack frame.
+class StackLayout {
+ unsigned MaxAlignment;
+
+ struct StackRegion {
+ unsigned Start;
+ unsigned End;
+ StackColoring::LiveRange Range;
+ StackRegion(unsigned Start, unsigned End,
+ const StackColoring::LiveRange &Range)
+ : Start(Start), End(End), Range(Range) {}
+ };
+ /// The list of current stack regions, sorted by StackRegion::Start.
+ SmallVector<StackRegion, 16> Regions;
+
+ struct StackObject {
+ const Value *Handle;
+ unsigned Size, Alignment;
+ StackColoring::LiveRange Range;
+ };
+ SmallVector<StackObject, 8> StackObjects;
+
+ DenseMap<const Value *, unsigned> ObjectOffsets;
+
+ void layoutObject(StackObject &Obj);
+
+public:
+ StackLayout(unsigned StackAlignment) : MaxAlignment(StackAlignment) {}
+ /// Add an object to the stack frame. Value pointer is opaque and used as a
+ /// handle to retrieve the object's offset in the frame later.
+ void addObject(const Value *V, unsigned Size, unsigned Alignment,
+ const StackColoring::LiveRange &Range);
+
+ /// Run the layout computation for all previously added objects.
+ void computeLayout();
+
+ /// Returns the offset to the object start in the stack frame.
+ unsigned getObjectOffset(const Value *V) { return ObjectOffsets[V]; }
+
+ /// Returns the size of the entire frame.
+ unsigned getFrameSize() { return Regions.empty() ? 0 : Regions.back().End; }
+
+ /// Returns the alignment of the frame.
+ unsigned getFrameAlignment() { return MaxAlignment; }
+ void print(raw_ostream &OS);
+};
+
+} // namespace safestack
+} // namespace llvm
+
+#endif // LLVM_LIB_CODEGEN_SAFESTACKLAYOUT_H
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