1 //===- SafeStackLayout.h - SafeStack frame layout --------------*- C++ -*--===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #ifndef LLVM_LIB_CODEGEN_SAFESTACKLAYOUT_H
11 #define LLVM_LIB_CODEGEN_SAFESTACKLAYOUT_H
13 #include "SafeStackColoring.h"
14 #include "llvm/ADT/DenseMap.h"
15 #include "llvm/ADT/SmallVector.h"
24 /// Compute the layout of an unsafe stack frame.
26 unsigned MaxAlignment;
31 StackColoring::LiveRange Range;
33 StackRegion(unsigned Start, unsigned End,
34 const StackColoring::LiveRange &Range)
35 : Start(Start), End(End), Range(Range) {}
38 /// The list of current stack regions, sorted by StackRegion::Start.
39 SmallVector<StackRegion, 16> Regions;
43 unsigned Size, Alignment;
44 StackColoring::LiveRange Range;
47 SmallVector<StackObject, 8> StackObjects;
49 DenseMap<const Value *, unsigned> ObjectOffsets;
51 void layoutObject(StackObject &Obj);
54 StackLayout(unsigned StackAlignment) : MaxAlignment(StackAlignment) {}
56 /// Add an object to the stack frame. Value pointer is opaque and used as a
57 /// handle to retrieve the object's offset in the frame later.
58 void addObject(const Value *V, unsigned Size, unsigned Alignment,
59 const StackColoring::LiveRange &Range);
61 /// Run the layout computation for all previously added objects.
64 /// Returns the offset to the object start in the stack frame.
65 unsigned getObjectOffset(const Value *V) { return ObjectOffsets[V]; }
67 /// Returns the size of the entire frame.
68 unsigned getFrameSize() { return Regions.empty() ? 0 : Regions.back().End; }
70 /// Returns the alignment of the frame.
71 unsigned getFrameAlignment() { return MaxAlignment; }
73 void print(raw_ostream &OS);
76 } // end namespace safestack
78 } // end namespace llvm
80 #endif // LLVM_LIB_CODEGEN_SAFESTACKLAYOUT_H