1 //===-- CallingConvLower.cpp - Calling Conventions ------------------------===//
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 // This file implements the CCState class, used for lowering and implementing
11 // calling conventions.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/CodeGen/CallingConvLower.h"
16 #include "llvm/CodeGen/MachineFrameInfo.h"
17 #include "llvm/Support/Debug.h"
18 #include "llvm/Support/ErrorHandling.h"
19 #include "llvm/Support/raw_ostream.h"
20 #include "llvm/Target/TargetRegisterInfo.h"
21 #include "llvm/Target/TargetData.h"
22 #include "llvm/Target/TargetMachine.h"
23 #include "llvm/Target/TargetLowering.h"
26 CCState::CCState(CallingConv::ID CC, bool isVarArg, MachineFunction &mf,
27 const TargetMachine &tm, SmallVector<CCValAssign, 16> &locs,
29 : CallingConv(CC), IsVarArg(isVarArg), MF(mf), TM(tm),
30 TRI(*TM.getRegisterInfo()), Locs(locs), Context(C),
31 CallOrPrologue(Unknown) {
36 UsedRegs.resize((TRI.getNumRegs()+31)/32);
39 // HandleByVal - Allocate space on the stack large enough to pass an argument
40 // by value. The size and alignment information of the argument is encoded in
41 // its parameter attribute.
42 void CCState::HandleByVal(unsigned ValNo, MVT ValVT,
43 MVT LocVT, CCValAssign::LocInfo LocInfo,
44 int MinSize, int MinAlign,
45 ISD::ArgFlagsTy ArgFlags) {
46 unsigned Align = ArgFlags.getByValAlign();
47 unsigned Size = ArgFlags.getByValSize();
48 if (MinSize > (int)Size)
50 if (MinAlign > (int)Align)
52 if (MF.getFrameInfo()->getMaxAlignment() < Align)
53 MF.getFrameInfo()->setMaxAlignment(Align);
54 TM.getTargetLowering()->HandleByVal(this, Size);
55 unsigned Offset = AllocateStack(Size, Align);
56 addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
59 /// MarkAllocated - Mark a register and all of its aliases as allocated.
60 void CCState::MarkAllocated(unsigned Reg) {
61 for (MCRegAliasIterator AI(Reg, &TRI, true); AI.isValid(); ++AI)
62 UsedRegs[*AI/32] |= 1 << (*AI&31);
65 /// AnalyzeFormalArguments - Analyze an array of argument values,
66 /// incorporating info about the formals into this state.
68 CCState::AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
70 unsigned NumArgs = Ins.size();
72 for (unsigned i = 0; i != NumArgs; ++i) {
73 MVT ArgVT = Ins[i].VT;
74 ISD::ArgFlagsTy ArgFlags = Ins[i].Flags;
75 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
77 dbgs() << "Formal argument #" << i << " has unhandled type "
78 << EVT(ArgVT).getEVTString();
85 /// CheckReturn - Analyze the return values of a function, returning true if
86 /// the return can be performed without sret-demotion, and false otherwise.
87 bool CCState::CheckReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
89 // Determine which register each value should be copied into.
90 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
92 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
93 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this))
99 /// AnalyzeReturn - Analyze the returned values of a return,
100 /// incorporating info about the result values into this state.
101 void CCState::AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
103 // Determine which register each value should be copied into.
104 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
106 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
107 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this)) {
109 dbgs() << "Return operand #" << i << " has unhandled type "
110 << EVT(VT).getEVTString();
117 /// AnalyzeCallOperands - Analyze the outgoing arguments to a call,
118 /// incorporating info about the passed values into this state.
119 void CCState::AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
121 unsigned NumOps = Outs.size();
122 for (unsigned i = 0; i != NumOps; ++i) {
123 MVT ArgVT = Outs[i].VT;
124 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
125 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
127 dbgs() << "Call operand #" << i << " has unhandled type "
128 << EVT(ArgVT).getEVTString();
135 /// AnalyzeCallOperands - Same as above except it takes vectors of types
136 /// and argument flags.
137 void CCState::AnalyzeCallOperands(SmallVectorImpl<MVT> &ArgVTs,
138 SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
140 unsigned NumOps = ArgVTs.size();
141 for (unsigned i = 0; i != NumOps; ++i) {
142 MVT ArgVT = ArgVTs[i];
143 ISD::ArgFlagsTy ArgFlags = Flags[i];
144 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
146 dbgs() << "Call operand #" << i << " has unhandled type "
147 << EVT(ArgVT).getEVTString();
154 /// AnalyzeCallResult - Analyze the return values of a call,
155 /// incorporating info about the passed values into this state.
156 void CCState::AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins,
158 for (unsigned i = 0, e = Ins.size(); i != e; ++i) {
160 ISD::ArgFlagsTy Flags = Ins[i].Flags;
161 if (Fn(i, VT, VT, CCValAssign::Full, Flags, *this)) {
163 dbgs() << "Call result #" << i << " has unhandled type "
164 << EVT(VT).getEVTString() << "\n";
171 /// AnalyzeCallResult - Same as above except it's specialized for calls which
172 /// produce a single value.
173 void CCState::AnalyzeCallResult(MVT VT, CCAssignFn Fn) {
174 if (Fn(0, VT, VT, CCValAssign::Full, ISD::ArgFlagsTy(), *this)) {
176 dbgs() << "Call result has unhandled type "
177 << EVT(VT).getEVTString();