LLVM 20.0.0git
SystemZCallingConv.h
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1//===-- SystemZCallingConv.h - Calling conventions for SystemZ --*- 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#ifndef LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZCALLINGCONV_H
10#define LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZCALLINGCONV_H
11
12#include "SystemZSubtarget.h"
16
17namespace llvm {
18namespace SystemZ {
19 const unsigned ELFNumArgGPRs = 5;
21
22 const unsigned ELFNumArgFPRs = 4;
24
25 const unsigned XPLINK64NumArgGPRs = 3;
27
28 const unsigned XPLINK64NumArgFPRs = 4;
30} // end namespace SystemZ
31
32class SystemZCCState : public CCState {
33private:
34 /// Records whether the value was a fixed argument.
35 /// See ISD::OutputArg::IsFixed.
36 SmallVector<bool, 4> ArgIsFixed;
37
38 /// Records whether the value was widened from a short vector type.
39 SmallVector<bool, 4> ArgIsShortVector;
40
41 // Check whether ArgVT is a short vector type.
42 bool IsShortVectorType(EVT ArgVT) {
43 return ArgVT.isVector() && ArgVT.getStoreSize() <= 8;
44 }
45
46public:
49 : CCState(CC, isVarArg, MF, locs, C) {}
50
52 CCAssignFn Fn) {
53 // Formal arguments are always fixed.
54 ArgIsFixed.clear();
55 for (unsigned i = 0; i < Ins.size(); ++i)
56 ArgIsFixed.push_back(true);
57 // Record whether the call operand was a short vector.
58 ArgIsShortVector.clear();
59 for (unsigned i = 0; i < Ins.size(); ++i)
60 ArgIsShortVector.push_back(IsShortVectorType(Ins[i].ArgVT));
61
63 }
64
66 CCAssignFn Fn) {
67 // Record whether the call operand was a fixed argument.
68 ArgIsFixed.clear();
69 for (unsigned i = 0; i < Outs.size(); ++i)
70 ArgIsFixed.push_back(Outs[i].IsFixed);
71 // Record whether the call operand was a short vector.
72 ArgIsShortVector.clear();
73 for (unsigned i = 0; i < Outs.size(); ++i)
74 ArgIsShortVector.push_back(IsShortVectorType(Outs[i].ArgVT));
75
77 }
78
79 // This version of AnalyzeCallOperands in the base class is not usable
80 // since we must provide a means of accessing ISD::OutputArg::IsFixed.
83 CCAssignFn Fn) = delete;
84
85 bool IsFixed(unsigned ValNo) { return ArgIsFixed[ValNo]; }
86 bool IsShortVector(unsigned ValNo) { return ArgIsShortVector[ValNo]; }
87};
88
89// Handle i128 argument types. These need to be passed by implicit
90// reference. This could be as simple as the following .td line:
91// CCIfType<[i128], CCPassIndirect<i64>>,
92// except that i128 is not a legal type, and therefore gets split by
93// common code into a pair of i64 arguments.
94inline bool CC_SystemZ_I128Indirect(unsigned &ValNo, MVT &ValVT,
95 MVT &LocVT,
96 CCValAssign::LocInfo &LocInfo,
97 ISD::ArgFlagsTy &ArgFlags,
98 CCState &State) {
99 SmallVectorImpl<CCValAssign> &PendingMembers = State.getPendingLocs();
100
101 // ArgFlags.isSplit() is true on the first part of a i128 argument;
102 // PendingMembers.empty() is false on all subsequent parts.
103 if (!ArgFlags.isSplit() && PendingMembers.empty())
104 return false;
105
106 // Push a pending Indirect value location for each part.
107 LocVT = MVT::i64;
108 LocInfo = CCValAssign::Indirect;
109 PendingMembers.push_back(CCValAssign::getPending(ValNo, ValVT,
110 LocVT, LocInfo));
111 if (!ArgFlags.isSplitEnd())
112 return true;
113
114 // OK, we've collected all parts in the pending list. Allocate
115 // the location (register or stack slot) for the indirect pointer.
116 // (This duplicates the usual i64 calling convention rules.)
117 unsigned Reg;
118 const SystemZSubtarget &Subtarget =
120 if (Subtarget.isTargetELF())
122 else if (Subtarget.isTargetXPLINK64())
124 else
125 llvm_unreachable("Unknown Calling Convention!");
126
127 unsigned Offset = Reg && !Subtarget.isTargetXPLINK64()
128 ? 0
129 : State.AllocateStack(8, Align(8));
130
131 // Use that same location for all the pending parts.
132 for (auto &It : PendingMembers) {
133 if (Reg)
134 It.convertToReg(Reg);
135 else
136 It.convertToMem(Offset);
137 State.addLoc(It);
138 }
139
140 PendingMembers.clear();
141
142 return true;
143}
144
145// A pointer in 64bit mode is always passed as 64bit.
146inline bool CC_XPLINK64_Pointer(unsigned &ValNo, MVT &ValVT, MVT &LocVT,
147 CCValAssign::LocInfo &LocInfo,
148 ISD::ArgFlagsTy &ArgFlags, CCState &State) {
149 if (LocVT != MVT::i64) {
150 LocVT = MVT::i64;
151 LocInfo = CCValAssign::ZExt;
152 }
153 return false;
154}
155
156inline bool CC_XPLINK64_Shadow_Reg(unsigned &ValNo, MVT &ValVT, MVT &LocVT,
157 CCValAssign::LocInfo &LocInfo,
158 ISD::ArgFlagsTy &ArgFlags, CCState &State) {
159 if (LocVT == MVT::f32 || LocVT == MVT::f64) {
161 }
162 if (LocVT == MVT::f128 || LocVT.is128BitVector()) {
163 // Shadow next two GPRs, if available.
166
167 // Quad precision floating point needs to
168 // go inside pre-defined FPR pair.
169 if (LocVT == MVT::f128) {
170 for (unsigned I = 0; I < SystemZ::XPLINK64NumArgFPRs; I += 2)
173 }
174 }
175 return false;
176}
177
178inline bool CC_XPLINK64_Allocate128BitVararg(unsigned &ValNo, MVT &ValVT,
179 MVT &LocVT,
180 CCValAssign::LocInfo &LocInfo,
181 ISD::ArgFlagsTy &ArgFlags,
182 CCState &State) {
183 // For any C or C++ program, this should always be
184 // false, since it is illegal to have a function
185 // where the first argument is variadic. Therefore
186 // the first fixed argument should already have
187 // allocated GPR1 either through shadowing it or
188 // using it for parameter passing.
189 State.AllocateReg(SystemZ::R1D);
190
191 bool AllocGPR2 = State.AllocateReg(SystemZ::R2D);
192 bool AllocGPR3 = State.AllocateReg(SystemZ::R3D);
193
194 // If GPR2 and GPR3 are available, then we may pass vararg in R2Q.
195 // If only GPR3 is available, we need to set custom handling to copy
196 // hi bits into GPR3.
197 // Either way, we allocate on the stack.
198 if (AllocGPR3) {
199 // For f128 and vector var arg case, set the bitcast flag to bitcast to
200 // i128.
201 LocVT = MVT::i128;
202 LocInfo = CCValAssign::BCvt;
203 auto Offset = State.AllocateStack(16, Align(8));
204 if (AllocGPR2)
205 State.addLoc(
206 CCValAssign::getReg(ValNo, ValVT, SystemZ::R2Q, LocVT, LocInfo));
207 else
208 State.addLoc(
209 CCValAssign::getCustomMem(ValNo, ValVT, Offset, LocVT, LocInfo));
210 return true;
211 }
212
213 return false;
214}
215
216inline bool RetCC_SystemZ_Error(unsigned &, MVT &, MVT &,
218 CCState &) {
219 llvm_unreachable("Return value calling convention currently unsupported.");
220}
221
222inline bool CC_SystemZ_Error(unsigned &, MVT &, MVT &, CCValAssign::LocInfo &,
224 llvm_unreachable("Argument calling convention currently unsupported.");
225}
226
227inline bool CC_SystemZ_GHC_Error(unsigned &, MVT &, MVT &,
229 CCState &) {
230 report_fatal_error("No registers left in GHC calling convention");
231 return false;
232}
233
234} // end namespace llvm
235
236#endif
#define I(x, y, z)
Definition: MD5.cpp:58
unsigned Reg
This file defines the SmallVector class.
CCState - This class holds information needed while lowering arguments and return values.
MachineFunction & getMachineFunction() const
MCRegister AllocateReg(MCPhysReg Reg)
AllocateReg - Attempt to allocate one register.
int64_t AllocateStack(unsigned Size, Align Alignment)
AllocateStack - Allocate a chunk of stack space with the specified size and alignment.
void AnalyzeCallOperands(const SmallVectorImpl< ISD::OutputArg > &Outs, CCAssignFn Fn)
AnalyzeCallOperands - Analyze the outgoing arguments to a call, incorporating info about the passed v...
SmallVectorImpl< CCValAssign > & getPendingLocs()
bool isVarArg() const
bool isAllocated(MCRegister Reg) const
isAllocated - Return true if the specified register (or an alias) is allocated.
void AnalyzeFormalArguments(const SmallVectorImpl< ISD::InputArg > &Ins, CCAssignFn Fn)
AnalyzeFormalArguments - Analyze an array of argument values, incorporating info about the formals in...
void addLoc(const CCValAssign &V)
static CCValAssign getPending(unsigned ValNo, MVT ValVT, MVT LocVT, LocInfo HTP, unsigned ExtraInfo=0)
static CCValAssign getReg(unsigned ValNo, MVT ValVT, unsigned RegNo, MVT LocVT, LocInfo HTP, bool IsCustom=false)
static CCValAssign getCustomMem(unsigned ValNo, MVT ValVT, int64_t Offset, MVT LocVT, LocInfo HTP)
This is an important class for using LLVM in a threaded context.
Definition: LLVMContext.h:67
Machine Value Type.
bool is128BitVector() const
Return true if this is a 128-bit vector type.
const TargetSubtargetInfo & getSubtarget() const
getSubtarget - Return the subtarget for which this machine code is being compiled.
bool empty() const
Definition: SmallVector.h:94
size_t size() const
Definition: SmallVector.h:91
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: SmallVector.h:586
void push_back(const T &Elt)
Definition: SmallVector.h:426
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1209
void AnalyzeCallOperands(const SmallVectorImpl< MVT > &Outs, SmallVectorImpl< ISD::ArgFlagsTy > &Flags, CCAssignFn Fn)=delete
SystemZCCState(CallingConv::ID CC, bool isVarArg, MachineFunction &MF, SmallVectorImpl< CCValAssign > &locs, LLVMContext &C)
void AnalyzeFormalArguments(const SmallVectorImpl< ISD::InputArg > &Ins, CCAssignFn Fn)
bool IsFixed(unsigned ValNo)
bool IsShortVector(unsigned ValNo)
void AnalyzeCallOperands(const SmallVectorImpl< ISD::OutputArg > &Outs, CCAssignFn Fn)
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
@ C
The default llvm calling convention, compatible with C.
Definition: CallingConv.h:34
const MCPhysReg XPLINK64ArgFPRs[XPLINK64NumArgFPRs]
const MCPhysReg ELFArgFPRs[ELFNumArgFPRs]
const unsigned XPLINK64NumArgFPRs
const unsigned XPLINK64NumArgGPRs
const MCPhysReg ELFArgGPRs[ELFNumArgGPRs]
const unsigned ELFNumArgGPRs
const unsigned ELFNumArgFPRs
const MCPhysReg XPLINK64ArgGPRs[XPLINK64NumArgGPRs]
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:480
bool CC_SystemZ_I128Indirect(unsigned &ValNo, MVT &ValVT, MVT &LocVT, CCValAssign::LocInfo &LocInfo, ISD::ArgFlagsTy &ArgFlags, CCState &State)
bool CC_XPLINK64_Pointer(unsigned &ValNo, MVT &ValVT, MVT &LocVT, CCValAssign::LocInfo &LocInfo, ISD::ArgFlagsTy &ArgFlags, CCState &State)
bool CC_XPLINK64_Allocate128BitVararg(unsigned &ValNo, MVT &ValVT, MVT &LocVT, CCValAssign::LocInfo &LocInfo, ISD::ArgFlagsTy &ArgFlags, CCState &State)
bool CC_SystemZ_GHC_Error(unsigned &, MVT &, MVT &, CCValAssign::LocInfo &, ISD::ArgFlagsTy &, CCState &)
void report_fatal_error(Error Err, bool gen_crash_diag=true)
Report a serious error, calling any installed error handler.
Definition: Error.cpp:167
bool RetCC_SystemZ_Error(unsigned &, MVT &, MVT &, CCValAssign::LocInfo &, ISD::ArgFlagsTy &, CCState &)
bool CC_SystemZ_Error(unsigned &, MVT &, MVT &, CCValAssign::LocInfo &, ISD::ArgFlagsTy &, CCState &)
bool CCAssignFn(unsigned ValNo, MVT ValVT, MVT LocVT, CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags, CCState &State)
CCAssignFn - This function assigns a location for Val, updating State to reflect the change.
bool CC_XPLINK64_Shadow_Reg(unsigned &ValNo, MVT &ValVT, MVT &LocVT, CCValAssign::LocInfo &LocInfo, ISD::ArgFlagsTy &ArgFlags, CCState &State)
This struct is a compact representation of a valid (non-zero power of two) alignment.
Definition: Alignment.h:39
Extended Value Type.
Definition: ValueTypes.h:35
TypeSize getStoreSize() const
Return the number of bytes overwritten by a store of the specified value type.
Definition: ValueTypes.h:381
bool isVector() const
Return true if this is a vector value type.
Definition: ValueTypes.h:168