1 //===-- SystemZCallingConv.h - Calling conventions for SystemZ --*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #ifndef LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZCALLINGCONV_H
11 #define LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZCALLINGCONV_H
12
13 #include "llvm/ADT/SmallVector.h"
14 #include "llvm/CodeGen/CallingConvLower.h"
15 #include "llvm/MC/MCRegisterInfo.h"
16
17 namespace llvm {
18 namespace SystemZ {
19 const unsigned NumArgGPRs = 5;
20 extern const MCPhysReg ArgGPRs[NumArgGPRs];
21
22 const unsigned NumArgFPRs = 4;
23 extern const MCPhysReg ArgFPRs[NumArgFPRs];
24 } // end namespace SystemZ
25
26 class SystemZCCState : public CCState {
27 private:
28 /// Records whether the value was a fixed argument.
29 /// See ISD::OutputArg::IsFixed.
30 SmallVector<bool, 4> ArgIsFixed;
31
32 /// Records whether the value was widened from a short vector type.
33 SmallVector<bool, 4> ArgIsShortVector;
34
35 // Check whether ArgVT is a short vector type.
IsShortVectorType(EVT ArgVT)36 bool IsShortVectorType(EVT ArgVT) {
37 return ArgVT.isVector() && ArgVT.getStoreSize() <= 8;
38 }
39
40 public:
SystemZCCState(CallingConv::ID CC,bool isVarArg,MachineFunction & MF,SmallVectorImpl<CCValAssign> & locs,LLVMContext & C)41 SystemZCCState(CallingConv::ID CC, bool isVarArg, MachineFunction &MF,
42 SmallVectorImpl<CCValAssign> &locs, LLVMContext &C)
43 : CCState(CC, isVarArg, MF, locs, C) {}
44
AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> & Ins,CCAssignFn Fn)45 void AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins,
46 CCAssignFn Fn) {
47 // Formal arguments are always fixed.
48 ArgIsFixed.clear();
49 for (unsigned i = 0; i < Ins.size(); ++i)
50 ArgIsFixed.push_back(true);
51 // Record whether the call operand was a short vector.
52 ArgIsShortVector.clear();
53 for (unsigned i = 0; i < Ins.size(); ++i)
54 ArgIsShortVector.push_back(IsShortVectorType(Ins[i].ArgVT));
55
56 CCState::AnalyzeFormalArguments(Ins, Fn);
57 }
58
AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> & Outs,CCAssignFn Fn)59 void AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs,
60 CCAssignFn Fn) {
61 // Record whether the call operand was a fixed argument.
62 ArgIsFixed.clear();
63 for (unsigned i = 0; i < Outs.size(); ++i)
64 ArgIsFixed.push_back(Outs[i].IsFixed);
65 // Record whether the call operand was a short vector.
66 ArgIsShortVector.clear();
67 for (unsigned i = 0; i < Outs.size(); ++i)
68 ArgIsShortVector.push_back(IsShortVectorType(Outs[i].ArgVT));
69
70 CCState::AnalyzeCallOperands(Outs, Fn);
71 }
72
73 // This version of AnalyzeCallOperands in the base class is not usable
74 // since we must provide a means of accessing ISD::OutputArg::IsFixed.
75 void AnalyzeCallOperands(const SmallVectorImpl<MVT> &Outs,
76 SmallVectorImpl<ISD::ArgFlagsTy> &Flags,
77 CCAssignFn Fn) = delete;
78
IsFixed(unsigned ValNo)79 bool IsFixed(unsigned ValNo) { return ArgIsFixed[ValNo]; }
IsShortVector(unsigned ValNo)80 bool IsShortVector(unsigned ValNo) { return ArgIsShortVector[ValNo]; }
81 };
82
83 // Handle i128 argument types. These need to be passed by implicit
84 // reference. This could be as simple as the following .td line:
85 // CCIfType<[i128], CCPassIndirect<i64>>,
86 // except that i128 is not a legal type, and therefore gets split by
87 // common code into a pair of i64 arguments.
CC_SystemZ_I128Indirect(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)88 inline bool CC_SystemZ_I128Indirect(unsigned &ValNo, MVT &ValVT,
89 MVT &LocVT,
90 CCValAssign::LocInfo &LocInfo,
91 ISD::ArgFlagsTy &ArgFlags,
92 CCState &State) {
93 SmallVectorImpl<CCValAssign> &PendingMembers = State.getPendingLocs();
94
95 // ArgFlags.isSplit() is true on the first part of a i128 argument;
96 // PendingMembers.empty() is false on all subsequent parts.
97 if (!ArgFlags.isSplit() && PendingMembers.empty())
98 return false;
99
100 // Push a pending Indirect value location for each part.
101 LocVT = MVT::i64;
102 LocInfo = CCValAssign::Indirect;
103 PendingMembers.push_back(CCValAssign::getPending(ValNo, ValVT,
104 LocVT, LocInfo));
105 if (!ArgFlags.isSplitEnd())
106 return true;
107
108 // OK, we've collected all parts in the pending list. Allocate
109 // the location (register or stack slot) for the indirect pointer.
110 // (This duplicates the usual i64 calling convention rules.)
111 unsigned Reg = State.AllocateReg(SystemZ::ArgGPRs);
112 unsigned Offset = Reg ? 0 : State.AllocateStack(8, 8);
113
114 // Use that same location for all the pending parts.
115 for (auto &It : PendingMembers) {
116 if (Reg)
117 It.convertToReg(Reg);
118 else
119 It.convertToMem(Offset);
120 State.addLoc(It);
121 }
122
123 PendingMembers.clear();
124
125 return true;
126 }
127
128 } // end namespace llvm
129
130 #endif
131