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, MVT ValVT,
38 MVT 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 for (const unsigned *Alias = TRI.getOverlaps(Reg);
55 unsigned Reg = *Alias; ++Alias)
56 UsedRegs[Reg/32] |= 1 << (Reg&31);
59 /// AnalyzeFormalArguments - Analyze an array of argument values,
60 /// incorporating info about the formals into this state.
62 CCState::AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
64 unsigned NumArgs = Ins.size();
66 for (unsigned i = 0; i != NumArgs; ++i) {
67 MVT ArgVT = Ins[i].VT;
68 ISD::ArgFlagsTy ArgFlags = Ins[i].Flags;
69 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
71 dbgs() << "Formal argument #" << i << " has unhandled type "
72 << EVT(ArgVT).getEVTString();
79 /// CheckReturn - Analyze the return values of a function, returning true if
80 /// the return can be performed without sret-demotion, and false otherwise.
81 bool CCState::CheckReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
83 // Determine which register each value should be copied into.
84 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
86 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
87 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this))
93 /// AnalyzeReturn - Analyze the returned values of a return,
94 /// incorporating info about the result values into this state.
95 void CCState::AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs,
97 // Determine which register each value should be copied into.
98 for (unsigned i = 0, e = Outs.size(); i != e; ++i) {
100 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
101 if (Fn(i, VT, VT, CCValAssign::Full, ArgFlags, *this)) {
103 dbgs() << "Return operand #" << i << " has unhandled type "
104 << EVT(VT).getEVTString();
111 /// AnalyzeCallOperands - Analyze the outgoing arguments to a call,
112 /// incorporating info about the passed values into this state.
113 void CCState::AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
115 unsigned NumOps = Outs.size();
116 for (unsigned i = 0; i != NumOps; ++i) {
117 MVT ArgVT = Outs[i].VT;
118 ISD::ArgFlagsTy ArgFlags = Outs[i].Flags;
119 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
121 dbgs() << "Call operand #" << i << " has unhandled type "
122 << EVT(ArgVT).getEVTString();
129 /// AnalyzeCallOperands - Same as above except it takes vectors of types
130 /// and argument flags.
131 void CCState::AnalyzeCallOperands(SmallVectorImpl<MVT> &ArgVTs,
132 SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
134 unsigned NumOps = ArgVTs.size();
135 for (unsigned i = 0; i != NumOps; ++i) {
136 MVT ArgVT = ArgVTs[i];
137 ISD::ArgFlagsTy ArgFlags = Flags[i];
138 if (Fn(i, ArgVT, ArgVT, CCValAssign::Full, ArgFlags, *this)) {
140 dbgs() << "Call operand #" << i << " has unhandled type "
141 << EVT(ArgVT).getEVTString();
148 /// AnalyzeCallResult - Analyze the return values of a call,
149 /// incorporating info about the passed values into this state.
150 void CCState::AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins,
152 for (unsigned i = 0, e = Ins.size(); i != e; ++i) {
154 ISD::ArgFlagsTy Flags = Ins[i].Flags;
155 if (Fn(i, VT, VT, CCValAssign::Full, Flags, *this)) {
157 dbgs() << "Call result #" << i << " has unhandled type "
158 << EVT(VT).getEVTString();
165 /// AnalyzeCallResult - Same as above except it's specialized for calls which
166 /// produce a single value.
167 void CCState::AnalyzeCallResult(MVT VT, CCAssignFn Fn) {
168 if (Fn(0, VT, VT, CCValAssign::Full, ISD::ArgFlagsTy(), *this)) {
170 dbgs() << "Call result has unhandled type "
171 << EVT(VT).getEVTString();