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AArch64MachineFunctionInfo.h
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1 //=- AArch64MachineFunctionInfo.h - AArch64 machine function info -*- C++ -*-=//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file declares AArch64-specific per-machine-function information.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_TARGET_AARCH64_AARCH64MACHINEFUNCTIONINFO_H
15 #define LLVM_LIB_TARGET_AARCH64_AARCH64MACHINEFUNCTIONINFO_H
16 
17 #include "llvm/ADT/ArrayRef.h"
18 #include "llvm/ADT/Optional.h"
19 #include "llvm/ADT/SmallPtrSet.h"
20 #include "llvm/ADT/SmallVector.h"
23 #include <cassert>
24 
25 namespace llvm {
26 
27 class MachineInstr;
28 
29 /// AArch64FunctionInfo - This class is derived from MachineFunctionInfo and
30 /// contains private AArch64-specific information for each MachineFunction.
32  /// Number of bytes of arguments this function has on the stack. If the callee
33  /// is expected to restore the argument stack this should be a multiple of 16,
34  /// all usable during a tail call.
35  ///
36  /// The alternative would forbid tail call optimisation in some cases: if we
37  /// want to transfer control from a function with 8-bytes of stack-argument
38  /// space to a function with 16-bytes then misalignment of this value would
39  /// make a stack adjustment necessary, which could not be undone by the
40  /// callee.
41  unsigned BytesInStackArgArea = 0;
42 
43  /// The number of bytes to restore to deallocate space for incoming
44  /// arguments. Canonically 0 in the C calling convention, but non-zero when
45  /// callee is expected to pop the args.
46  unsigned ArgumentStackToRestore = 0;
47 
48  /// HasStackFrame - True if this function has a stack frame. Set by
49  /// determineCalleeSaves().
50  bool HasStackFrame = false;
51 
52  /// Amount of stack frame size, not including callee-saved registers.
53  unsigned LocalStackSize;
54 
55  /// Amount of stack frame size used for saving callee-saved registers.
56  unsigned CalleeSavedStackSize;
57 
58  /// Number of TLS accesses using the special (combinable)
59  /// _TLS_MODULE_BASE_ symbol.
60  unsigned NumLocalDynamicTLSAccesses = 0;
61 
62  /// FrameIndex for start of varargs area for arguments passed on the
63  /// stack.
64  int VarArgsStackIndex = 0;
65 
66  /// FrameIndex for start of varargs area for arguments passed in
67  /// general purpose registers.
68  int VarArgsGPRIndex = 0;
69 
70  /// Size of the varargs area for arguments passed in general purpose
71  /// registers.
72  unsigned VarArgsGPRSize = 0;
73 
74  /// FrameIndex for start of varargs area for arguments passed in
75  /// floating-point registers.
76  int VarArgsFPRIndex = 0;
77 
78  /// Size of the varargs area for arguments passed in floating-point
79  /// registers.
80  unsigned VarArgsFPRSize = 0;
81 
82  /// True if this function has a subset of CSRs that is handled explicitly via
83  /// copies.
84  bool IsSplitCSR = false;
85 
86  /// True when the stack gets realigned dynamically because the size of stack
87  /// frame is unknown at compile time. e.g., in case of VLAs.
88  bool StackRealigned = false;
89 
90  /// True when the callee-save stack area has unused gaps that may be used for
91  /// other stack allocations.
92  bool CalleeSaveStackHasFreeSpace = false;
93 
94  /// Has a value when it is known whether or not the function uses a
95  /// redzone, and no value otherwise.
96  /// Initialized during frame lowering, unless the function has the noredzone
97  /// attribute, in which case it is set to false at construction.
98  Optional<bool> HasRedZone;
99 
100 public:
101  AArch64FunctionInfo() = default;
102 
104  (void)MF;
105 
106  // If we already know that the function doesn't have a redzone, set
107  // HasRedZone here.
108  if (MF.getFunction().hasFnAttribute(Attribute::NoRedZone))
109  HasRedZone = false;
110  }
111 
112  unsigned getBytesInStackArgArea() const { return BytesInStackArgArea; }
113  void setBytesInStackArgArea(unsigned bytes) { BytesInStackArgArea = bytes; }
114 
115  unsigned getArgumentStackToRestore() const { return ArgumentStackToRestore; }
116  void setArgumentStackToRestore(unsigned bytes) {
117  ArgumentStackToRestore = bytes;
118  }
119 
120  bool hasStackFrame() const { return HasStackFrame; }
121  void setHasStackFrame(bool s) { HasStackFrame = s; }
122 
123  bool isStackRealigned() const { return StackRealigned; }
124  void setStackRealigned(bool s) { StackRealigned = s; }
125 
127  return CalleeSaveStackHasFreeSpace;
128  }
130  CalleeSaveStackHasFreeSpace = s;
131  }
132 
133  bool isSplitCSR() const { return IsSplitCSR; }
134  void setIsSplitCSR(bool s) { IsSplitCSR = s; }
135 
136  void setLocalStackSize(unsigned Size) { LocalStackSize = Size; }
137  unsigned getLocalStackSize() const { return LocalStackSize; }
138 
139  void setCalleeSavedStackSize(unsigned Size) { CalleeSavedStackSize = Size; }
140  unsigned getCalleeSavedStackSize() const { return CalleeSavedStackSize; }
141 
142  void incNumLocalDynamicTLSAccesses() { ++NumLocalDynamicTLSAccesses; }
143  unsigned getNumLocalDynamicTLSAccesses() const {
144  return NumLocalDynamicTLSAccesses;
145  }
146 
147  Optional<bool> hasRedZone() const { return HasRedZone; }
148  void setHasRedZone(bool s) { HasRedZone = s; }
149 
150  int getVarArgsStackIndex() const { return VarArgsStackIndex; }
151  void setVarArgsStackIndex(int Index) { VarArgsStackIndex = Index; }
152 
153  int getVarArgsGPRIndex() const { return VarArgsGPRIndex; }
154  void setVarArgsGPRIndex(int Index) { VarArgsGPRIndex = Index; }
155 
156  unsigned getVarArgsGPRSize() const { return VarArgsGPRSize; }
157  void setVarArgsGPRSize(unsigned Size) { VarArgsGPRSize = Size; }
158 
159  int getVarArgsFPRIndex() const { return VarArgsFPRIndex; }
160  void setVarArgsFPRIndex(int Index) { VarArgsFPRIndex = Index; }
161 
162  unsigned getVarArgsFPRSize() const { return VarArgsFPRSize; }
163  void setVarArgsFPRSize(unsigned Size) { VarArgsFPRSize = Size; }
164 
166 
167  const SetOfInstructions &getLOHRelated() const { return LOHRelated; }
168 
169  // Shortcuts for LOH related types.
171  MCLOHType Kind;
172 
173  /// Arguments of this directive. Order matters.
175 
176  public:
178 
180  : Kind(Kind), Args(Args.begin(), Args.end()) {
181  assert(isValidMCLOHType(Kind) && "Invalid LOH directive type!");
182  }
183 
184  MCLOHType getKind() const { return Kind; }
185  LOHArgs getArgs() const { return Args; }
186  };
187 
190 
191  const MILOHContainer &getLOHContainer() const { return LOHContainerSet; }
192 
193  /// Add a LOH directive of this @p Kind and this @p Args.
195  LOHContainerSet.push_back(MILOHDirective(Kind, Args));
196  LOHRelated.insert(Args.begin(), Args.end());
197  }
198 
199 private:
200  // Hold the lists of LOHs.
201  MILOHContainer LOHContainerSet;
202  SetOfInstructions LOHRelated;
203 };
204 
205 } // end namespace llvm
206 
207 #endif // LLVM_LIB_TARGET_AARCH64_AARCH64MACHINEFUNCTIONINFO_H
const_iterator end(StringRef path)
Get end iterator over path.
Definition: Path.cpp:250
AArch64FunctionInfo - This class is derived from MachineFunctionInfo and contains private AArch64-spe...
const_iterator begin(StringRef path, Style style=Style::native)
Get begin iterator over path.
Definition: Path.cpp:241
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
iterator begin() const
Definition: ArrayRef.h:137
const SetOfInstructions & getLOHRelated() const
bool hasFnAttribute(Attribute::AttrKind Kind) const
Return true if the function has the attribute.
Definition: Function.h:307
MachineFunctionInfo - This class can be derived from and used by targets to hold private target-speci...
void setArgumentStackToRestore(unsigned bytes)
AArch64FunctionInfo(MachineFunction &MF)
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:33
MCLOHType
Linker Optimization Hint Type.
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:861
iterator end() const
Definition: ArrayRef.h:138
const Function & getFunction() const
Return the LLVM function that this machine code represents.
Optional< bool > hasRedZone() const
const MILOHContainer & getLOHContainer() const
static bool isValidMCLOHType(unsigned Kind)
void setBytesInStackArgArea(unsigned bytes)
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
void addLOHDirective(MCLOHType Kind, MILOHArgs Args)
Add a LOH directive of this Kind and this Args.
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
void setCalleeSavedStackSize(unsigned Size)