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<ISD::OutputArg> &Outs,
85 // Determine which register each value should be copied into.
86 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
88 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
89 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this))
95 /// AnalyzeReturn - Analyze the returned values of a return,
96 /// incorporating info about the result values into this state.
97 void CCState::AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
99 // Determine which register each value should be copied into.
100 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
102 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
103 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this)) {
105 dbgs() << "Return operand #" << i << " has unhandled type "
106 << VT.getEVTString();
113 /// AnalyzeCallOperands - Analyze the outgoing arguments to a call,
114 /// incorporating info about the passed values into this state.
115 void CCState::AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
117 unsigned NumOps = Outs.size();
118 for (unsigned i = 0; i != NumOps; ++i) {
119 EVT ArgVT = Outs[i].VT;
120 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
121 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
123 dbgs() << "Call operand #" << i << " has unhandled type "
124 << ArgVT.getEVTString();
131 /// AnalyzeCallOperands - Same as above except it takes vectors of types
132 /// and argument flags.
133 void CCState::AnalyzeCallOperands(SmallVectorImpl<EVT> &ArgVTs,
134 SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
136 unsigned NumOps = ArgVTs.size();
137 for (unsigned i = 0; i != NumOps; ++i) {
138 EVT ArgVT = ArgVTs[i];
139 ISD::ArgFlagsTy ArgFlags = Flags[i];
140 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
142 dbgs() << "Call operand #" << i << " has unhandled type "
143 << ArgVT.getEVTString();
150 /// AnalyzeCallResult - Analyze the return values of a call,
151 /// incorporating info about the passed values into this state.
152 void CCState::AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins,
154 for (unsigned i = 0, e = Ins.size(); i != e; ++i) {
156 ISD::ArgFlagsTy Flags = Ins[i].Flags;
157 if (Fn(i, VT, VT, CCValAssign::Full, Flags, *this)) {
159 dbgs() << "Call result #" << i << " has unhandled type "
160 << VT.getEVTString();
167 /// AnalyzeCallResult - Same as above except it's specialized for calls which
168 /// produce a single value.
169 void CCState::AnalyzeCallResult(EVT VT, CCAssignFn Fn) {
170 if (Fn(0, VT, VT, CCValAssign::Full, ISD::ArgFlagsTy(), *this)) {
172 dbgs() << "Call result has unhandled type "
173 << VT.getEVTString();