1//=- AArch64CallingConv.td - Calling Conventions for AArch64 -*- tablegen -*-=//
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// This describes the calling conventions for AArch64 architecture.
11//
12//===----------------------------------------------------------------------===//
13
14/// CCIfAlign - Match of the original alignment of the arg
15class CCIfAlign<string Align, CCAction A> :
16  CCIf<!strconcat("ArgFlags.getOrigAlign() == ", Align), A>;
17/// CCIfBigEndian - Match only if we're in big endian mode.
18class CCIfBigEndian<CCAction A> :
19  CCIf<"State.getMachineFunction().getSubtarget().getDataLayout()->isBigEndian()", A>;
20
21//===----------------------------------------------------------------------===//
22// ARM AAPCS64 Calling Convention
23//===----------------------------------------------------------------------===//
24
25def CC_AArch64_AAPCS : CallingConv<[
26  CCIfType<[v2f32], CCBitConvertToType<v2i32>>,
27  CCIfType<[v2f64, v4f32], CCBitConvertToType<v2i64>>,
28
29  // Big endian vectors must be passed as if they were 1-element vectors so that
30  // their lanes are in a consistent order.
31  CCIfBigEndian<CCIfType<[v2i32, v2f32, v4i16, v4f16, v8i8],
32                         CCBitConvertToType<f64>>>,
33  CCIfBigEndian<CCIfType<[v2i64, v2f64, v4i32, v4f32, v8i16, v8f16, v16i8],
34                         CCBitConvertToType<f128>>>,
35
36  // An SRet is passed in X8, not X0 like a normal pointer parameter.
37  CCIfSRet<CCIfType<[i64], CCAssignToRegWithShadow<[X8], [W8]>>>,
38
39  // Put ByVal arguments directly on the stack. Minimum size and alignment of a
40  // slot is 64-bit.
41  CCIfByVal<CCPassByVal<8, 8>>,
42
43  CCIfConsecutiveRegs<CCCustom<"CC_AArch64_Custom_Block">>,
44
45  // Handle i1, i8, i16, i32, i64, f32, f64 and v2f64 by passing in registers,
46  // up to eight each of GPR and FPR.
47  CCIfType<[i1, i8, i16], CCPromoteToType<i32>>,
48  CCIfType<[i32], CCAssignToRegWithShadow<[W0, W1, W2, W3, W4, W5, W6, W7],
49                                          [X0, X1, X2, X3, X4, X5, X6, X7]>>,
50  // i128 is split to two i64s, we can't fit half to register X7.
51  CCIfType<[i64], CCIfSplit<CCAssignToRegWithShadow<[X0, X2, X4, X6],
52                                                    [X0, X1, X3, X5]>>>,
53
54  // i128 is split to two i64s, and its stack alignment is 16 bytes.
55  CCIfType<[i64], CCIfSplit<CCAssignToStackWithShadow<8, 16, [X7]>>>,
56
57  CCIfType<[i64], CCAssignToRegWithShadow<[X0, X1, X2, X3, X4, X5, X6, X7],
58                                          [W0, W1, W2, W3, W4, W5, W6, W7]>>,
59  CCIfType<[f16], CCAssignToRegWithShadow<[H0, H1, H2, H3, H4, H5, H6, H7],
60                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
61  CCIfType<[f32], CCAssignToRegWithShadow<[S0, S1, S2, S3, S4, S5, S6, S7],
62                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
63  CCIfType<[f64], CCAssignToRegWithShadow<[D0, D1, D2, D3, D4, D5, D6, D7],
64                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
65  CCIfType<[v1i64, v2i32, v4i16, v8i8, v1f64, v2f32, v4f16],
66           CCAssignToRegWithShadow<[D0, D1, D2, D3, D4, D5, D6, D7],
67                                   [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
68  CCIfType<[f128, v2i64, v4i32, v8i16, v16i8, v4f32, v2f64, v8f16],
69           CCAssignToReg<[Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
70
71  // If more than will fit in registers, pass them on the stack instead.
72  CCIfType<[i1, i8, i16, f16], CCAssignToStack<8, 8>>,
73  CCIfType<[i32, f32], CCAssignToStack<8, 8>>,
74  CCIfType<[i64, f64, v1f64, v2f32, v1i64, v2i32, v4i16, v8i8, v4f16],
75           CCAssignToStack<8, 8>>,
76  CCIfType<[f128, v2i64, v4i32, v8i16, v16i8, v4f32, v2f64, v8f16],
77           CCAssignToStack<16, 16>>
78]>;
79
80def RetCC_AArch64_AAPCS : CallingConv<[
81  CCIfType<[v2f32], CCBitConvertToType<v2i32>>,
82  CCIfType<[v2f64, v4f32], CCBitConvertToType<v2i64>>,
83
84  // Big endian vectors must be passed as if they were 1-element vectors so that
85  // their lanes are in a consistent order.
86  CCIfBigEndian<CCIfType<[v2i32, v2f32, v4i16, v4f16, v8i8],
87                         CCBitConvertToType<f64>>>,
88  CCIfBigEndian<CCIfType<[v2i64, v2f64, v4i32, v4f32, v8i16, v8f16, v16i8],
89                         CCBitConvertToType<f128>>>,
90
91  CCIfType<[i32], CCAssignToRegWithShadow<[W0, W1, W2, W3, W4, W5, W6, W7],
92                                          [X0, X1, X2, X3, X4, X5, X6, X7]>>,
93  CCIfType<[i64], CCAssignToRegWithShadow<[X0, X1, X2, X3, X4, X5, X6, X7],
94                                          [W0, W1, W2, W3, W4, W5, W6, W7]>>,
95  CCIfType<[f16], CCAssignToRegWithShadow<[H0, H1, H2, H3, H4, H5, H6, H7],
96                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
97  CCIfType<[f32], CCAssignToRegWithShadow<[S0, S1, S2, S3, S4, S5, S6, S7],
98                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
99  CCIfType<[f64], CCAssignToRegWithShadow<[D0, D1, D2, D3, D4, D5, D6, D7],
100                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
101  CCIfType<[v1i64, v2i32, v4i16, v8i8, v1f64, v2f32, v4f16],
102      CCAssignToRegWithShadow<[D0, D1, D2, D3, D4, D5, D6, D7],
103                              [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
104  CCIfType<[f128, v2i64, v4i32, v8i16, v16i8, v4f32, v2f64, v8f16],
105      CCAssignToReg<[Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>
106]>;
107
108
109// Darwin uses a calling convention which differs in only two ways
110// from the standard one at this level:
111//     + i128s (i.e. split i64s) don't need even registers.
112//     + Stack slots are sized as needed rather than being at least 64-bit.
113def CC_AArch64_DarwinPCS : CallingConv<[
114  CCIfType<[v2f32], CCBitConvertToType<v2i32>>,
115  CCIfType<[v2f64, v4f32, f128], CCBitConvertToType<v2i64>>,
116
117  // An SRet is passed in X8, not X0 like a normal pointer parameter.
118  CCIfSRet<CCIfType<[i64], CCAssignToRegWithShadow<[X8], [W8]>>>,
119
120  // Put ByVal arguments directly on the stack. Minimum size and alignment of a
121  // slot is 64-bit.
122  CCIfByVal<CCPassByVal<8, 8>>,
123
124  CCIfConsecutiveRegs<CCCustom<"CC_AArch64_Custom_Block">>,
125
126  // Handle i1, i8, i16, i32, i64, f32, f64 and v2f64 by passing in registers,
127  // up to eight each of GPR and FPR.
128  CCIfType<[i1, i8, i16], CCPromoteToType<i32>>,
129  CCIfType<[i32], CCAssignToRegWithShadow<[W0, W1, W2, W3, W4, W5, W6, W7],
130                                          [X0, X1, X2, X3, X4, X5, X6, X7]>>,
131  // i128 is split to two i64s, we can't fit half to register X7.
132  CCIfType<[i64],
133           CCIfSplit<CCAssignToRegWithShadow<[X0, X1, X2, X3, X4, X5, X6],
134                                             [W0, W1, W2, W3, W4, W5, W6]>>>,
135  // i128 is split to two i64s, and its stack alignment is 16 bytes.
136  CCIfType<[i64], CCIfSplit<CCAssignToStackWithShadow<8, 16, [X7]>>>,
137
138  CCIfType<[i64], CCAssignToRegWithShadow<[X0, X1, X2, X3, X4, X5, X6, X7],
139                                          [W0, W1, W2, W3, W4, W5, W6, W7]>>,
140  CCIfType<[f16], CCAssignToRegWithShadow<[H0, H1, H2, H3, H4, H5, H6, H7],
141                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
142  CCIfType<[f32], CCAssignToRegWithShadow<[S0, S1, S2, S3, S4, S5, S6, S7],
143                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
144  CCIfType<[f64], CCAssignToRegWithShadow<[D0, D1, D2, D3, D4, D5, D6, D7],
145                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
146  CCIfType<[v1i64, v2i32, v4i16, v8i8, v1f64, v2f32, v4f16],
147           CCAssignToRegWithShadow<[D0, D1, D2, D3, D4, D5, D6, D7],
148                                   [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
149  CCIfType<[v2i64, v4i32, v8i16, v16i8, v4f32, v2f64, v8f16],
150           CCAssignToReg<[Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
151
152  // If more than will fit in registers, pass them on the stack instead.
153  CCIf<"ValVT == MVT::i1 || ValVT == MVT::i8", CCAssignToStack<1, 1>>,
154  CCIf<"ValVT == MVT::i16 || ValVT == MVT::f16", CCAssignToStack<2, 2>>,
155  CCIfType<[i32, f32], CCAssignToStack<4, 4>>,
156  CCIfType<[i64, f64, v1f64, v2f32, v1i64, v2i32, v4i16, v8i8, v4f16],
157           CCAssignToStack<8, 8>>,
158  CCIfType<[v2i64, v4i32, v8i16, v16i8, v4f32, v2f64, v8f16],
159           CCAssignToStack<16, 16>>
160]>;
161
162def CC_AArch64_DarwinPCS_VarArg : CallingConv<[
163  CCIfType<[v2f32], CCBitConvertToType<v2i32>>,
164  CCIfType<[v2f64, v4f32, f128], CCBitConvertToType<v2i64>>,
165
166  CCIfConsecutiveRegs<CCCustom<"CC_AArch64_Custom_Stack_Block">>,
167
168  // Handle all scalar types as either i64 or f64.
169  CCIfType<[i8, i16, i32], CCPromoteToType<i64>>,
170  CCIfType<[f16, f32],     CCPromoteToType<f64>>,
171
172  // Everything is on the stack.
173  // i128 is split to two i64s, and its stack alignment is 16 bytes.
174  CCIfType<[i64], CCIfSplit<CCAssignToStack<8, 16>>>,
175  CCIfType<[i64, f64, v1i64, v2i32, v4i16, v8i8, v1f64, v2f32, v4f16],
176           CCAssignToStack<8, 8>>,
177  CCIfType<[v2i64, v4i32, v8i16, v16i8, v4f32, v2f64, v8f16],
178           CCAssignToStack<16, 16>>
179]>;
180
181// The WebKit_JS calling convention only passes the first argument (the callee)
182// in register and the remaining arguments on stack. We allow 32bit stack slots,
183// so that WebKit can write partial values in the stack and define the other
184// 32bit quantity as undef.
185def CC_AArch64_WebKit_JS : CallingConv<[
186  // Handle i1, i8, i16, i32, and i64 passing in register X0 (W0).
187  CCIfType<[i1, i8, i16], CCPromoteToType<i32>>,
188  CCIfType<[i32], CCAssignToRegWithShadow<[W0], [X0]>>,
189  CCIfType<[i64], CCAssignToRegWithShadow<[X0], [W0]>>,
190
191  // Pass the remaining arguments on the stack instead.
192  CCIfType<[i32, f32], CCAssignToStack<4, 4>>,
193  CCIfType<[i64, f64], CCAssignToStack<8, 8>>
194]>;
195
196def RetCC_AArch64_WebKit_JS : CallingConv<[
197  CCIfType<[i32], CCAssignToRegWithShadow<[W0, W1, W2, W3, W4, W5, W6, W7],
198                                          [X0, X1, X2, X3, X4, X5, X6, X7]>>,
199  CCIfType<[i64], CCAssignToRegWithShadow<[X0, X1, X2, X3, X4, X5, X6, X7],
200                                          [W0, W1, W2, W3, W4, W5, W6, W7]>>,
201  CCIfType<[f32], CCAssignToRegWithShadow<[S0, S1, S2, S3, S4, S5, S6, S7],
202                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>,
203  CCIfType<[f64], CCAssignToRegWithShadow<[D0, D1, D2, D3, D4, D5, D6, D7],
204                                          [Q0, Q1, Q2, Q3, Q4, Q5, Q6, Q7]>>
205]>;
206
207//===----------------------------------------------------------------------===//
208// ARM64 Calling Convention for GHC
209//===----------------------------------------------------------------------===//
210
211// This calling convention is specific to the Glasgow Haskell Compiler.
212// The only documentation is the GHC source code, specifically the C header
213// file:
214//
215//     https://github.com/ghc/ghc/blob/master/includes/stg/MachRegs.h
216//
217// which defines the registers for the Spineless Tagless G-Machine (STG) that
218// GHC uses to implement lazy evaluation. The generic STG machine has a set of
219// registers which are mapped to appropriate set of architecture specific
220// registers for each CPU architecture.
221//
222// The STG Machine is documented here:
223//
224//    https://ghc.haskell.org/trac/ghc/wiki/Commentary/Compiler/GeneratedCode
225//
226// The AArch64 register mapping is under the heading "The ARMv8/AArch64 ABI
227// register mapping".
228
229def CC_AArch64_GHC : CallingConv<[
230  // Handle all vector types as either f64 or v2f64.
231  CCIfType<[v1i64, v2i32, v4i16, v8i8, v2f32], CCBitConvertToType<f64>>,
232  CCIfType<[v2i64, v4i32, v8i16, v16i8, v4f32, f128], CCBitConvertToType<v2f64>>,
233
234  CCIfType<[v2f64], CCAssignToReg<[Q4, Q5]>>,
235  CCIfType<[f32], CCAssignToReg<[S8, S9, S10, S11]>>,
236  CCIfType<[f64], CCAssignToReg<[D12, D13, D14, D15]>>,
237
238  // Promote i8/i16/i32 arguments to i64.
239  CCIfType<[i8, i16, i32], CCPromoteToType<i64>>,
240
241  // Pass in STG registers: Base, Sp, Hp, R1, R2, R3, R4, R5, R6, SpLim
242  CCIfType<[i64], CCAssignToReg<[X19, X20, X21, X22, X23, X24, X25, X26, X27, X28]>>
243]>;
244
245// FIXME: LR is only callee-saved in the sense that *we* preserve it and are
246// presumably a callee to someone. External functions may not do so, but this
247// is currently safe since BL has LR as an implicit-def and what happens after a
248// tail call doesn't matter.
249//
250// It would be better to model its preservation semantics properly (create a
251// vreg on entry, use it in RET & tail call generation; make that vreg def if we
252// end up saving LR as part of a call frame). Watch this space...
253def CSR_AArch64_AAPCS : CalleeSavedRegs<(add LR, FP, X19, X20, X21, X22,
254                                           X23, X24, X25, X26, X27, X28,
255                                           D8,  D9,  D10, D11,
256                                           D12, D13, D14, D15)>;
257
258// Constructors and destructors return 'this' in the iOS 64-bit C++ ABI; since
259// 'this' and the pointer return value are both passed in X0 in these cases,
260// this can be partially modelled by treating X0 as a callee-saved register;
261// only the resulting RegMask is used; the SaveList is ignored
262//
263// (For generic ARM 64-bit ABI code, clang will not generate constructors or
264// destructors with 'this' returns, so this RegMask will not be used in that
265// case)
266def CSR_AArch64_AAPCS_ThisReturn : CalleeSavedRegs<(add CSR_AArch64_AAPCS, X0)>;
267
268// The function used by Darwin to obtain the address of a thread-local variable
269// guarantees more than a normal AAPCS function. x16 and x17 are used on the
270// fast path for calculation, but other registers except X0 (argument/return)
271// and LR (it is a call, after all) are preserved.
272def CSR_AArch64_TLS_Darwin
273    : CalleeSavedRegs<(add (sub (sequence "X%u", 1, 28), X16, X17),
274                           FP,
275                           (sequence "Q%u", 0, 31))>;
276
277// The ELF stub used for TLS-descriptor access saves every feasible
278// register. Only X0 and LR are clobbered.
279def CSR_AArch64_TLS_ELF
280    : CalleeSavedRegs<(add (sequence "X%u", 1, 28), FP,
281                           (sequence "Q%u", 0, 31))>;
282
283def CSR_AArch64_AllRegs
284    : CalleeSavedRegs<(add (sequence "W%u", 0, 30), WSP,
285                           (sequence "X%u", 0, 28), FP, LR, SP,
286                           (sequence "B%u", 0, 31), (sequence "H%u", 0, 31),
287                           (sequence "S%u", 0, 31), (sequence "D%u", 0, 31),
288                           (sequence "Q%u", 0, 31))>;
289
290def CSR_AArch64_NoRegs : CalleeSavedRegs<(add)>;
291