1 //===- X86CallingConv.td - Calling Conventions X86 32/64 ---*- tablegen -*-===//
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 describes the calling conventions for the X86-32 and X86-64
13 //===----------------------------------------------------------------------===//
15 /// CCIfSubtarget - Match if the current subtarget has a feature F.
16 class CCIfSubtarget<string F, CCAction A>
17 : CCIf<!strconcat("State.getTarget().getSubtarget<X86Subtarget>().", F), A>;
19 //===----------------------------------------------------------------------===//
20 // Return Value Calling Conventions
21 //===----------------------------------------------------------------------===//
23 // Return-value conventions common to all X86 CC's.
24 def RetCC_X86Common : CallingConv<[
25 // Scalar values are returned in AX first, then DX.
26 CCIfType<[i8] , CCAssignToReg<[AL]>>,
27 CCIfType<[i16], CCAssignToReg<[AX]>>,
28 CCIfType<[i32], CCAssignToReg<[EAX, EDX]>>,
29 CCIfType<[i64], CCAssignToReg<[RAX, RDX]>>,
31 // Vector types are returned in XMM0 and XMM1, when they fit. If the target
32 // doesn't have XMM registers, it won't have vector types.
33 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
34 CCAssignToReg<[XMM0,XMM1]>>,
36 // MMX vector types are always returned in MM0. If the target doesn't have
37 // MM0, it doesn't support these vector types.
38 CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToReg<[MM0]>>,
40 // Long double types are always returned in ST0 (even with SSE).
41 CCIfType<[f80], CCAssignToReg<[ST0, ST1]>>
44 // X86-32 C return-value convention.
45 def RetCC_X86_32_C : CallingConv<[
46 // The X86-32 calling convention returns FP values in ST0, otherwise it is the
47 // same as the common X86 calling conv.
48 CCIfType<[f32], CCAssignToReg<[ST0, ST1]>>,
49 CCIfType<[f64], CCAssignToReg<[ST0, ST1]>>,
50 CCDelegateTo<RetCC_X86Common>
53 // X86-32 FastCC return-value convention.
54 def RetCC_X86_32_Fast : CallingConv<[
55 // The X86-32 fastcc returns 1, 2, or 3 FP values in XMM0-2 if the target has
56 // SSE2, otherwise it is the the C calling conventions.
57 // This can happen when a float, 2 x float, or 3 x float vector is split by
58 // target lowering, and is returned in 1-3 sse regs.
59 CCIfType<[f32], CCIfSubtarget<"hasSSE2()", CCAssignToReg<[XMM0,XMM1,XMM2]>>>,
60 CCIfType<[f64], CCIfSubtarget<"hasSSE2()", CCAssignToReg<[XMM0,XMM1,XMM2]>>>,
61 CCDelegateTo<RetCC_X86Common>
64 // X86-32 SSEregparm return-value convention.
65 def RetCC_X86_32_SSE : CallingConv<[
66 // The X86-32 sseregparm calling convention returns FP values in XMM0 if the
67 // target has SSE2, otherwise it is the C calling convention.
68 CCIfType<[f32], CCIfSubtarget<"hasSSE2()", CCAssignToReg<[XMM0]>>>,
69 CCIfType<[f64], CCIfSubtarget<"hasSSE2()", CCAssignToReg<[XMM0]>>>,
70 CCDelegateTo<RetCC_X86Common>
73 // X86-64 C return-value convention.
74 def RetCC_X86_64_C : CallingConv<[
75 // The X86-64 calling convention always returns FP values in XMM0.
76 CCIfType<[f32], CCAssignToReg<[XMM0]>>,
77 CCIfType<[f64], CCAssignToReg<[XMM0]>>,
78 CCDelegateTo<RetCC_X86Common>
81 // X86-Win64 C return-value convention.
82 def RetCC_X86_Win64_C : CallingConv<[
83 // The X86-Win64 calling convention always returns __m64 values in RAX
84 CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToReg<[RAX]>>,
86 // Otherwise, everything is the same as 'norma' X86-64 C CC
87 CCDelegateTo<RetCC_X86_64_C>
91 // This is the root return-value convention for the X86-32 backend.
92 def RetCC_X86_32 : CallingConv<[
93 // If FastCC, use RetCC_X86_32_Fast.
94 CCIfCC<"CallingConv::Fast", CCDelegateTo<RetCC_X86_32_Fast>>,
95 // If SSECC, use RetCC_X86_32_SSE.
96 CCIfCC<"CallingConv::X86_SSECall", CCDelegateTo<RetCC_X86_32_SSE>>,
97 // Otherwise, use RetCC_X86_32_C.
98 CCDelegateTo<RetCC_X86_32_C>
101 // This is the root return-value convention for the X86-64 backend.
102 def RetCC_X86_64 : CallingConv<[
103 // Mingw64 and native Win64 use Win64 CC
104 CCIfSubtarget<"isTargetWin64()", CCDelegateTo<RetCC_X86_Win64_C>>,
106 // Otherwise, drop to normal X86-64 CC
107 CCDelegateTo<RetCC_X86_64_C>
110 // This is the return-value convention used for the entire X86 backend.
111 def RetCC_X86 : CallingConv<[
112 CCIfSubtarget<"is64Bit()", CCDelegateTo<RetCC_X86_64>>,
113 CCDelegateTo<RetCC_X86_32>
116 //===----------------------------------------------------------------------===//
117 // X86-64 Argument Calling Conventions
118 //===----------------------------------------------------------------------===//
120 def CC_X86_64_C : CallingConv<[
121 // Handles byval parameters.
122 CCIfByVal<CCPassByVal<8, 8>>,
124 // Promote i8/i16 arguments to i32.
125 CCIfType<[i8, i16], CCPromoteToType<i32>>,
127 // The 'nest' parameter, if any, is passed in R10.
128 CCIfNest<CCAssignToReg<[R10]>>,
130 // The first 6 integer arguments are passed in integer registers.
131 CCIfType<[i32], CCAssignToReg<[EDI, ESI, EDX, ECX, R8D, R9D]>>,
132 CCIfType<[i64], CCAssignToReg<[RDI, RSI, RDX, RCX, R8 , R9 ]>>,
134 // The first 8 FP/Vector arguments are passed in XMM registers.
135 CCIfType<[f32, f64, v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
136 CCAssignToReg<[XMM0, XMM1, XMM2, XMM3, XMM4, XMM5, XMM6, XMM7]>>,
138 // The first 8 MMX vector arguments are passed in GPRs.
139 CCIfType<[v8i8, v4i16, v2i32, v1i64],
140 CCAssignToReg<[RDI, RSI, RDX, RCX, R8 , R9 ]>>,
142 // Integer/FP values get stored in stack slots that are 8 bytes in size and
143 // 8-byte aligned if there are no more registers to hold them.
144 CCIfType<[i32, i64, f32, f64], CCAssignToStack<8, 8>>,
146 // Long doubles get stack slots whose size and alignment depends on the
148 CCIfType<[f80], CCAssignToStack<0, 0>>,
150 // Vectors get 16-byte stack slots that are 16-byte aligned.
151 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], CCAssignToStack<16, 16>>,
153 // __m64 vectors get 8-byte stack slots that are 8-byte aligned.
154 CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToStack<8, 8>>
157 // Calling convention used on Win64
158 def CC_X86_Win64_C : CallingConv<[
159 // FIXME: Handle byval stuff
160 // FIXME: Handle fp80
161 // FIXME: Handle shadowed arguments
163 // Promote i8/i16 arguments to i32.
164 CCIfType<[i8, i16], CCPromoteToType<i32>>,
166 // The first 4 integer arguments are passed in integer registers.
167 CCIfType<[i32], CCAssignToReg<[ECX, EDX, R8D, R9D]>>,
168 CCIfType<[i64], CCAssignToReg<[RCX, RDX, R8 , R9 ]>>,
170 // The first 4 FP/Vector arguments are passed in XMM registers.
171 CCIfType<[f32, f64, v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
172 CCAssignToReg<[XMM0, XMM1, XMM2, XMM3]>>,
174 // The first 4 MMX vector arguments are passed in GPRs.
175 CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToReg<[RCX, RDX, R8, R9]>>,
177 // Integer/FP values get stored in stack slots that are 8 bytes in size and
178 // 16-byte aligned if there are no more registers to hold them.
179 CCIfType<[i32, i64, f32, f64], CCAssignToStack<8, 16>>,
181 // Vectors get 16-byte stack slots that are 16-byte aligned.
182 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], CCAssignToStack<16, 16>>,
184 // __m64 vectors get 8-byte stack slots that are 16-byte aligned.
185 CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToStack<8, 16>>
188 // Tail call convention (fast): One register is reserved for target address,
190 def CC_X86_64_TailCall : CallingConv<[
191 // Handles byval parameters.
192 CCIfByVal<CCPassByVal<8, 8>>,
194 // Promote i8/i16 arguments to i32.
195 CCIfType<[i8, i16], CCPromoteToType<i32>>,
197 // The 'nest' parameter, if any, is passed in R10.
198 CCIfNest<CCAssignToReg<[R10]>>,
200 // The first 6 integer arguments are passed in integer registers.
201 CCIfType<[i32], CCAssignToReg<[EDI, ESI, EDX, ECX, R8D]>>,
202 CCIfType<[i64], CCAssignToReg<[RDI, RSI, RDX, RCX, R8]>>,
204 // The first 8 FP/Vector arguments are passed in XMM registers.
205 CCIfType<[f32, f64, v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
206 CCAssignToReg<[XMM0, XMM1, XMM2, XMM3, XMM4, XMM5, XMM6, XMM7]>>,
208 // The first 8 MMX vector arguments are passed in GPRs.
209 CCIfType<[v8i8, v4i16, v2i32, v1i64],
210 CCAssignToReg<[RDI, RSI, RDX, RCX, R8]>>,
212 // Integer/FP values get stored in stack slots that are 8 bytes in size and
213 // 8-byte aligned if there are no more registers to hold them.
214 CCIfType<[i32, i64, f32, f64], CCAssignToStack<8, 8>>,
216 // Vectors get 16-byte stack slots that are 16-byte aligned.
217 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], CCAssignToStack<16, 16>>,
219 // __m64 vectors get 8-byte stack slots that are 8-byte aligned.
220 CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToStack<8, 8>>
224 //===----------------------------------------------------------------------===//
225 // X86 C Calling Convention
226 //===----------------------------------------------------------------------===//
228 /// CC_X86_32_Common - In all X86-32 calling conventions, extra integers and FP
229 /// values are spilled on the stack, and the first 4 vector values go in XMM
231 def CC_X86_32_Common : CallingConv<[
232 // Handles byval parameters.
233 CCIfByVal<CCPassByVal<4, 4>>,
235 // The first 3 float or double arguments, if marked 'inreg' and if the call
236 // is not a vararg call and if SSE2 is available, are passed in SSE registers.
237 CCIfNotVarArg<CCIfInReg<CCIfType<[f32,f64], CCIfSubtarget<"hasSSE2()",
238 CCAssignToReg<[XMM0,XMM1,XMM2]>>>>>,
240 // Integer/Float values get stored in stack slots that are 4 bytes in
241 // size and 4-byte aligned.
242 CCIfType<[i32, f32], CCAssignToStack<4, 4>>,
244 // Doubles get 8-byte slots that are 4-byte aligned.
245 CCIfType<[f64], CCAssignToStack<8, 4>>,
247 // Long doubles get slots whose size depends on the subtarget.
248 CCIfType<[f80], CCAssignToStack<0, 4>>,
250 // The first 4 SSE vector arguments are passed in XMM registers.
251 CCIfNotVarArg<CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
252 CCAssignToReg<[XMM0, XMM1, XMM2, XMM3]>>>,
254 // Other SSE vectors get 16-byte stack slots that are 16-byte aligned.
255 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], CCAssignToStack<16, 16>>,
257 // __m64 vectors get 8-byte stack slots that are 4-byte aligned. They are
258 // passed in the parameter area.
259 CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToStack<8, 4>>
262 def CC_X86_32_C : CallingConv<[
263 // Promote i8/i16 arguments to i32.
264 CCIfType<[i8, i16], CCPromoteToType<i32>>,
266 // The 'nest' parameter, if any, is passed in ECX.
267 CCIfNest<CCAssignToReg<[ECX]>>,
269 // The first 3 integer arguments, if marked 'inreg' and if the call is not
270 // a vararg call, are passed in integer registers.
271 CCIfNotVarArg<CCIfInReg<CCIfType<[i32], CCAssignToReg<[EAX, EDX, ECX]>>>>,
273 // Otherwise, same as everything else.
274 CCDelegateTo<CC_X86_32_Common>
277 /// Same as C calling convention except for non-free ECX which is used for storing
278 /// a potential pointer to the tail called function.
279 def CC_X86_32_TailCall : CallingConv<[
280 // Promote i8/i16 arguments to i32.
281 CCIfType<[i8, i16], CCPromoteToType<i32>>,
283 // Nested function trampolines are currently not supported by fastcc.
285 // The first 3 integer arguments, if marked 'inreg' and if the call is not
286 // a vararg call, are passed in integer registers.
287 CCIfNotVarArg<CCIfInReg<CCIfType<[i32], CCAssignToReg<[EAX, EDX]>>>>,
289 // Otherwise, same as everything else.
290 CCDelegateTo<CC_X86_32_Common>
293 def CC_X86_32_FastCall : CallingConv<[
294 // Promote i8/i16 arguments to i32.
295 CCIfType<[i8, i16], CCPromoteToType<i32>>,
297 // The 'nest' parameter, if any, is passed in EAX.
298 CCIfNest<CCAssignToReg<[EAX]>>,
300 // The first 2 integer arguments are passed in ECX/EDX
301 CCIfType<[i32], CCAssignToReg<[ECX, EDX]>>,
303 // Otherwise, same as everything else.
304 CCDelegateTo<CC_X86_32_Common>