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/Support/Debug.h"
17 #include "llvm/Support/ErrorHandling.h"
18 #include "llvm/Support/raw_ostream.h"
19 #include "llvm/Target/TargetRegisterInfo.h"
20 #include "llvm/Target/TargetData.h"
21 #include "llvm/Target/TargetMachine.h"
22 #include "llvm/Target/TargetLowering.h"
25 CCState::CCState(CallingConv::ID CC, bool isVarArg, const TargetMachine &tm,
26 SmallVector<CCValAssign, 16> &locs, LLVMContext &C)
27 : CallingConv(CC), IsVarArg(isVarArg), TM(tm),
28 TRI(*TM.getRegisterInfo()), Locs(locs), Context(C),
29 CallOrPrologue(Invalid) {
34 UsedRegs.resize((TRI.getNumRegs()+31)/32);
37 // HandleByVal - Allocate a stack slot large enough to pass an argument by
38 // value. The size and alignment information of the argument is encoded in its
39 // parameter attribute.
40 void CCState::HandleByVal(unsigned ValNo, MVT ValVT,
41 MVT LocVT, CCValAssign::LocInfo LocInfo,
42 int MinSize, int MinAlign,
43 ISD::ArgFlagsTy ArgFlags) {
44 unsigned Align = ArgFlags.getByValAlign();
45 unsigned Size = ArgFlags.getByValSize();
46 if (MinSize > (int)Size)
48 if (MinAlign > (int)Align)
50 TM.getTargetLowering()->HandleByVal(const_cast<CCState*>(this), Size);
51 unsigned Offset = AllocateStack(Size, Align);
52 addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
55 /// MarkAllocated - Mark a register and all of its aliases as allocated.
56 void CCState::MarkAllocated(unsigned Reg) {
57 for (const unsigned *Alias = TRI.getOverlaps(Reg);
58 unsigned Reg = *Alias; ++Alias)
59 UsedRegs[Reg/32] |= 1 << (Reg&31);
62 /// AnalyzeFormalArguments - Analyze an array of argument values,
63 /// incorporating info about the formals into this state.
65 CCState::AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
67 unsigned NumArgs = Ins.size();
69 for (unsigned i = 0; i != NumArgs; ++i) {
70 MVT ArgVT = Ins[i].VT;
71 ISD::ArgFlagsTy ArgFlags = Ins[i].Flags;
72 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
74 dbgs() << "Formal argument #" << i << " has unhandled type "
75 << EVT(ArgVT).getEVTString();
82 /// CheckReturn - Analyze the return values of a function, returning true if
83 /// the return can be performed without sret-demotion, and false otherwise.
84 bool CCState::CheckReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
86 // Determine which register each value should be copied into.
87 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
89 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
90 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this))
96 /// AnalyzeReturn - Analyze the returned values of a return,
97 /// incorporating info about the result values into this state.
98 void CCState::AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
100 // Determine which register each value should be copied into.
101 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
103 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
104 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this)) {
106 dbgs() << "Return operand #" << i << " has unhandled type "
107 << EVT(VT).getEVTString();
114 /// AnalyzeCallOperands - Analyze the outgoing arguments to a call,
115 /// incorporating info about the passed values into this state.
116 void CCState::AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
118 unsigned NumOps = Outs.size();
119 for (unsigned i = 0; i != NumOps; ++i) {
120 MVT ArgVT = Outs[i].VT;
121 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
122 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
124 dbgs() << "Call operand #" << i << " has unhandled type "
125 << EVT(ArgVT).getEVTString();
132 /// AnalyzeCallOperands - Same as above except it takes vectors of types
133 /// and argument flags.
134 void CCState::AnalyzeCallOperands(SmallVectorImpl<MVT> &ArgVTs,
135 SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
137 unsigned NumOps = ArgVTs.size();
138 for (unsigned i = 0; i != NumOps; ++i) {
139 MVT ArgVT = ArgVTs[i];
140 ISD::ArgFlagsTy ArgFlags = Flags[i];
141 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
143 dbgs() << "Call operand #" << i << " has unhandled type "
144 << EVT(ArgVT).getEVTString();
151 /// AnalyzeCallResult - Analyze the return values of a call,
152 /// incorporating info about the passed values into this state.
153 void CCState::AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins,
155 for (unsigned i = 0, e = Ins.size(); i != e; ++i) {
157 ISD::ArgFlagsTy Flags = Ins[i].Flags;
158 if (Fn(i, VT, VT, CCValAssign::Full, Flags, *this)) {
160 dbgs() << "Call result #" << i << " has unhandled type "
161 << EVT(VT).getEVTString() << "\n";
168 /// AnalyzeCallResult - Same as above except it's specialized for calls which
169 /// produce a single value.
170 void CCState::AnalyzeCallResult(MVT VT, CCAssignFn Fn) {
171 if (Fn(0, VT, VT, CCValAssign::Full, ISD::ArgFlagsTy(), *this)) {
173 dbgs() << "Call result has unhandled type "
174 << EVT(VT).getEVTString();