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 (const uint16_t *Alias = TRI.getOverlaps(Reg);
62 unsigned Reg = *Alias; ++Alias)
63 UsedRegs[Reg/32] |= 1 << (Reg&31);
66 /// AnalyzeFormalArguments - Analyze an array of argument values,
67 /// incorporating info about the formals into this state.
69 CCState::AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
71 unsigned NumArgs = Ins.size();
73 for (unsigned i = 0; i != NumArgs; ++i) {
74 MVT ArgVT = Ins[i].VT;
75 ISD::ArgFlagsTy ArgFlags = Ins[i].Flags;
76 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
78 dbgs() << "Formal argument #" << i << " has unhandled type "
79 << EVT(ArgVT).getEVTString();
86 /// CheckReturn - Analyze the return values of a function, returning true if
87 /// the return can be performed without sret-demotion, and false otherwise.
88 bool CCState::CheckReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
90 // Determine which register each value should be copied into.
91 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
93 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
94 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this))
100 /// AnalyzeReturn - Analyze the returned values of a return,
101 /// incorporating info about the result values into this state.
102 void CCState::AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
104 // Determine which register each value should be copied into.
105 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
107 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
108 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this)) {
110 dbgs() << "Return operand #" << i << " has unhandled type "
111 << EVT(VT).getEVTString();
118 /// AnalyzeCallOperands - Analyze the outgoing arguments to a call,
119 /// incorporating info about the passed values into this state.
120 void CCState::AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
122 unsigned NumOps = Outs.size();
123 for (unsigned i = 0; i != NumOps; ++i) {
124 MVT ArgVT = Outs[i].VT;
125 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
126 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
128 dbgs() << "Call operand #" << i << " has unhandled type "
129 << EVT(ArgVT).getEVTString();
136 /// AnalyzeCallOperands - Same as above except it takes vectors of types
137 /// and argument flags.
138 void CCState::AnalyzeCallOperands(SmallVectorImpl<MVT> &ArgVTs,
139 SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
141 unsigned NumOps = ArgVTs.size();
142 for (unsigned i = 0; i != NumOps; ++i) {
143 MVT ArgVT = ArgVTs[i];
144 ISD::ArgFlagsTy ArgFlags = Flags[i];
145 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
147 dbgs() << "Call operand #" << i << " has unhandled type "
148 << EVT(ArgVT).getEVTString();
155 /// AnalyzeCallResult - Analyze the return values of a call,
156 /// incorporating info about the passed values into this state.
157 void CCState::AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins,
159 for (unsigned i = 0, e = Ins.size(); i != e; ++i) {
161 ISD::ArgFlagsTy Flags = Ins[i].Flags;
162 if (Fn(i, VT, VT, CCValAssign::Full, Flags, *this)) {
164 dbgs() << "Call result #" << i << " has unhandled type "
165 << EVT(VT).getEVTString() << "\n";
172 /// AnalyzeCallResult - Same as above except it's specialized for calls which
173 /// produce a single value.
174 void CCState::AnalyzeCallResult(MVT VT, CCAssignFn Fn) {
175 if (Fn(0, VT, VT, CCValAssign::Full, ISD::ArgFlagsTy(), *this)) {
177 dbgs() << "Call result has unhandled type "
178 << EVT(VT).getEVTString();