1 //===-- PPCCallingConv.h - --------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #include "PPCRegisterInfo.h"
10 #include "PPCCallingConv.h"
11 #include "PPCSubtarget.h"
12 #include "PPCCCState.h"
13 using namespace llvm;
14
CC_PPC_AnyReg_Error(unsigned &,MVT &,MVT &,CCValAssign::LocInfo &,ISD::ArgFlagsTy &,CCState &)15 inline bool CC_PPC_AnyReg_Error(unsigned &, MVT &, MVT &,
16 CCValAssign::LocInfo &, ISD::ArgFlagsTy &,
17 CCState &) {
18 llvm_unreachable("The AnyReg calling convention is only supported by the " \
19 "stackmap and patchpoint intrinsics.");
20 // gracefully fallback to PPC C calling convention on Release builds.
21 return false;
22 }
23
CC_PPC32_SVR4_Custom_Dummy(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)24 static bool CC_PPC32_SVR4_Custom_Dummy(unsigned &ValNo, MVT &ValVT, MVT &LocVT,
25 CCValAssign::LocInfo &LocInfo,
26 ISD::ArgFlagsTy &ArgFlags,
27 CCState &State) {
28 return true;
29 }
30
CC_PPC32_SVR4_Custom_AlignArgRegs(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)31 static bool CC_PPC32_SVR4_Custom_AlignArgRegs(unsigned &ValNo, MVT &ValVT,
32 MVT &LocVT,
33 CCValAssign::LocInfo &LocInfo,
34 ISD::ArgFlagsTy &ArgFlags,
35 CCState &State) {
36 static const MCPhysReg ArgRegs[] = {
37 PPC::R3, PPC::R4, PPC::R5, PPC::R6,
38 PPC::R7, PPC::R8, PPC::R9, PPC::R10,
39 };
40 const unsigned NumArgRegs = array_lengthof(ArgRegs);
41
42 unsigned RegNum = State.getFirstUnallocated(ArgRegs);
43
44 // Skip one register if the first unallocated register has an even register
45 // number and there are still argument registers available which have not been
46 // allocated yet. RegNum is actually an index into ArgRegs, which means we
47 // need to skip a register if RegNum is odd.
48 if (RegNum != NumArgRegs && RegNum % 2 == 1) {
49 State.AllocateReg(ArgRegs[RegNum]);
50 }
51
52 // Always return false here, as this function only makes sure that the first
53 // unallocated register has an odd register number and does not actually
54 // allocate a register for the current argument.
55 return false;
56 }
57
CC_PPC32_SVR4_Custom_SkipLastArgRegsPPCF128(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)58 static bool CC_PPC32_SVR4_Custom_SkipLastArgRegsPPCF128(
59 unsigned &ValNo, MVT &ValVT, MVT &LocVT, CCValAssign::LocInfo &LocInfo,
60 ISD::ArgFlagsTy &ArgFlags, CCState &State) {
61 static const MCPhysReg ArgRegs[] = {
62 PPC::R3, PPC::R4, PPC::R5, PPC::R6,
63 PPC::R7, PPC::R8, PPC::R9, PPC::R10,
64 };
65 const unsigned NumArgRegs = array_lengthof(ArgRegs);
66
67 unsigned RegNum = State.getFirstUnallocated(ArgRegs);
68 int RegsLeft = NumArgRegs - RegNum;
69
70 // Skip if there is not enough registers left for long double type (4 gpr regs
71 // in soft float mode) and put long double argument on the stack.
72 if (RegNum != NumArgRegs && RegsLeft < 4) {
73 for (int i = 0; i < RegsLeft; i++) {
74 State.AllocateReg(ArgRegs[RegNum + i]);
75 }
76 }
77
78 return false;
79 }
80
CC_PPC32_SVR4_Custom_AlignFPArgRegs(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)81 static bool CC_PPC32_SVR4_Custom_AlignFPArgRegs(unsigned &ValNo, MVT &ValVT,
82 MVT &LocVT,
83 CCValAssign::LocInfo &LocInfo,
84 ISD::ArgFlagsTy &ArgFlags,
85 CCState &State) {
86 static const MCPhysReg ArgRegs[] = {
87 PPC::F1, PPC::F2, PPC::F3, PPC::F4, PPC::F5, PPC::F6, PPC::F7,
88 PPC::F8
89 };
90
91 const unsigned NumArgRegs = array_lengthof(ArgRegs);
92
93 unsigned RegNum = State.getFirstUnallocated(ArgRegs);
94
95 // If there is only one Floating-point register left we need to put both f64
96 // values of a split ppc_fp128 value on the stack.
97 if (RegNum != NumArgRegs && ArgRegs[RegNum] == PPC::F8) {
98 State.AllocateReg(ArgRegs[RegNum]);
99 }
100
101 // Always return false here, as this function only makes sure that the two f64
102 // values a ppc_fp128 value is split into are both passed in registers or both
103 // passed on the stack and does not actually allocate a register for the
104 // current argument.
105 return false;
106 }
107
108 // Split F64 arguments into two 32-bit consecutive registers.
CC_PPC32_SPE_CustomSplitFP64(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)109 static bool CC_PPC32_SPE_CustomSplitFP64(unsigned &ValNo, MVT &ValVT,
110 MVT &LocVT,
111 CCValAssign::LocInfo &LocInfo,
112 ISD::ArgFlagsTy &ArgFlags,
113 CCState &State) {
114 static const MCPhysReg HiRegList[] = { PPC::R3, PPC::R5, PPC::R7, PPC::R9 };
115 static const MCPhysReg LoRegList[] = { PPC::R4, PPC::R6, PPC::R8, PPC::R10 };
116
117 // Try to get the first register.
118 unsigned Reg = State.AllocateReg(HiRegList);
119 if (!Reg)
120 return false;
121
122 unsigned i;
123 for (i = 0; i < sizeof(HiRegList) / sizeof(HiRegList[0]); ++i)
124 if (HiRegList[i] == Reg)
125 break;
126
127 unsigned T = State.AllocateReg(LoRegList[i]);
128 (void)T;
129 assert(T == LoRegList[i] && "Could not allocate register");
130
131 State.addLoc(CCValAssign::getCustomReg(ValNo, ValVT, Reg, LocVT, LocInfo));
132 State.addLoc(CCValAssign::getCustomReg(ValNo, ValVT, LoRegList[i],
133 LocVT, LocInfo));
134 return true;
135 }
136
137 // Same as above, but for return values, so only allocate for R3 and R4
CC_PPC32_SPE_RetF64(unsigned & ValNo,MVT & ValVT,MVT & LocVT,CCValAssign::LocInfo & LocInfo,ISD::ArgFlagsTy & ArgFlags,CCState & State)138 static bool CC_PPC32_SPE_RetF64(unsigned &ValNo, MVT &ValVT,
139 MVT &LocVT,
140 CCValAssign::LocInfo &LocInfo,
141 ISD::ArgFlagsTy &ArgFlags,
142 CCState &State) {
143 static const MCPhysReg HiRegList[] = { PPC::R3 };
144 static const MCPhysReg LoRegList[] = { PPC::R4 };
145
146 // Try to get the first register.
147 unsigned Reg = State.AllocateReg(HiRegList, LoRegList);
148 if (!Reg)
149 return false;
150
151 unsigned i;
152 for (i = 0; i < sizeof(HiRegList) / sizeof(HiRegList[0]); ++i)
153 if (HiRegList[i] == Reg)
154 break;
155
156 State.addLoc(CCValAssign::getCustomReg(ValNo, ValVT, Reg, LocVT, LocInfo));
157 State.addLoc(CCValAssign::getCustomReg(ValNo, ValVT, LoRegList[i],
158 LocVT, LocInfo));
159 return true;
160 }
161
162 #include "PPCGenCallingConv.inc"
163