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"
24 CCState::CCState(CallingConv::ID CC, bool isVarArg, const TargetMachine &tm,
25 SmallVector<CCValAssign, 16> &locs, LLVMContext &C)
26 : CallingConv(CC), IsVarArg(isVarArg), TM(tm),
27 TRI(*TM.getRegisterInfo()), Locs(locs), Context(C) {
31 UsedRegs.resize((TRI.getNumRegs()+31)/32);
34 // HandleByVal - Allocate a stack slot large enough to pass an argument by
35 // value. The size and alignment information of the argument is encoded in its
36 // parameter attribute.
37 void CCState::HandleByVal(unsigned ValNo, EVT ValVT,
38 EVT LocVT, CCValAssign::LocInfo LocInfo,
39 int MinSize, int MinAlign,
40 ISD::ArgFlagsTy ArgFlags) {
41 unsigned Align = ArgFlags.getByValAlign();
42 unsigned Size = ArgFlags.getByValSize();
43 if (MinSize > (int)Size)
45 if (MinAlign > (int)Align)
47 unsigned Offset = AllocateStack(Size, Align);
49 addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
52 /// MarkAllocated - Mark a register and all of its aliases as allocated.
53 void CCState::MarkAllocated(unsigned Reg) {
54 UsedRegs[Reg/32] |= 1 << (Reg&31);
56 if (const unsigned *RegAliases = TRI.getAliasSet(Reg))
57 for (; (Reg = *RegAliases); ++RegAliases)
58 UsedRegs[Reg/32] |= 1 << (Reg&31);
61 /// AnalyzeFormalArguments - Analyze an array of argument values,
62 /// incorporating info about the formals into this state.
64 CCState::AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
66 unsigned NumArgs = Ins.size();
68 for (unsigned i = 0; i != NumArgs; ++i) {
69 EVT ArgVT = Ins[i].VT;
70 ISD::ArgFlagsTy ArgFlags = Ins[i].Flags;
71 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
73 dbgs() << "Formal argument #" << i << " has unhandled type "
74 << ArgVT.getEVTString();
81 /// CheckReturn - Analyze the return values of a function, returning true if
82 /// the return can be performed without sret-demotion, and false otherwise.
83 bool CCState::CheckReturn(const SmallVectorImpl<EVT> &OutTys,
84 const SmallVectorImpl<ISD::ArgFlagsTy> &ArgsFlags,
86 // Determine which register each value should be copied into.
87 for (unsigned i = 0, e = OutTys.size(); i != e; ++i) {
89 ISD::ArgFlagsTy ArgFlags = ArgsFlags[i];
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 << 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 EVT 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 << ArgVT.getEVTString();
132 /// AnalyzeCallOperands - Same as above except it takes vectors of types
133 /// and argument flags.
134 void CCState::AnalyzeCallOperands(SmallVectorImpl<EVT> &ArgVTs,
135 SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
137 unsigned NumOps = ArgVTs.size();
138 for (unsigned i = 0; i != NumOps; ++i) {
139 EVT 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 << 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 << VT.getEVTString();
168 /// AnalyzeCallResult - Same as above except it's specialized for calls which
169 /// produce a single value.
170 void CCState::AnalyzeCallResult(EVT VT, CCAssignFn Fn) {
171 if (Fn(0, VT, VT, CCValAssign::Full, ISD::ArgFlagsTy(), *this)) {
173 dbgs() << "Call result has unhandled type "
174 << VT.getEVTString();