1 //===- X86CallingConv.td - Calling Conventions for X86 32/64 ----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Chris Lattner and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This describes the calling conventions for the X86-32 and X86-64
13 //===----------------------------------------------------------------------===//
18 /// CCPredicateAction - Instances of this class check some predicate, then
19 /// delegate to another action if the predicate is true.
20 class CCPredicateAction<CCAction A> : CCAction {
21 CCAction SubAction = A;
24 /// CCMatchType - If the current argument is one of the specified types, apply
26 class CCMatchType<list<ValueType> VTs, CCAction A> : CCPredicateAction<A> {
29 /// CCMatchIf - If the predicate matches, apply A.
30 class CCMatchIf<string predicate, CCAction A> : CCPredicateAction<A> {
31 string Predicate = predicate;
34 /// CCMatchIfCC - Match of the current calling convention is 'CC'.
35 class CCMatchIfCC<string CC, CCAction A> : CCPredicateAction<A> {
36 string CallingConv = CC;
39 /// CCAssignToReg - This action matches if there is a register in the specified
40 /// list that is still available. If so, it assigns the value to the first
41 /// available register and succeeds.
42 class CCAssignToReg<list<Register> regList> : CCAction {
43 list<Register> RegList = regList;
46 /// CCAssignToStack - This action always matches: it assigns the value to a
47 /// stack slot of the specified size and alignment on the stack.
48 class CCAssignToStack<int size, int align> : CCAction {
54 /// CCPromoteToType - If applied, this promotes the specified current value to
55 /// the specified type.
56 class CCPromoteToType<ValueType destTy> : CCAction {
57 ValueType DestTy = destTy;
60 /// CCDelegateTo - This action invokes the specified sub-calling-convention. It
61 /// is successful if the specified CC matches.
62 class CCDelegateTo<CallingConv cc> : CCAction {
67 class CallingConv<list<CCAction> actions> {
68 list<CCAction> Actions = actions;
71 //===----------------------------------------------------------------------===//
72 // Return Value Calling Conventions
73 //===----------------------------------------------------------------------===//
75 // Return-value conventions common to all X86 CC's.
76 def RetCC_X86Common : CallingConv<[
77 // Scalar values are returned in AX first, then DX.
78 CCMatchType<[i8] , CCAssignToReg<[AL]>>,
79 CCMatchType<[i16], CCAssignToReg<[AX]>>,
80 CCMatchType<[i32], CCAssignToReg<[EAX, EDX]>>,
81 CCMatchType<[i64], CCAssignToReg<[RAX, RDX]>>,
83 // Vector types are always returned in XMM0. If the target doesn't have XMM0,
84 // it won't have vector types.
85 CCMatchType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], CCAssignToReg<[XMM0]>>
88 // X86-32 C return-value convention.
89 def RetCC_X86_32_C : CallingConv<[
90 // The X86-32 calling convention returns FP values in ST0, otherwise it is the
91 // same as the common X86 calling conv.
92 CCMatchType<[f32], CCAssignToReg<[ST0]>>,
93 CCMatchType<[f64], CCAssignToReg<[ST0]>>,
94 CCDelegateTo<RetCC_X86Common>
97 // X86-32 FastCC return-value convention.
98 def RetCC_X86_32_Fast : CallingConv<[
99 // The X86-32 fastcc returns FP values in XMM0 if the target has SSE2,
100 // otherwise it is the the C calling conventions.
101 CCMatchType<[f32], CCMatchIf<"Subtarget->hasSSE2()", CCAssignToReg<[XMM0]>>>,
102 CCMatchType<[f64], CCMatchIf<"Subtarget->hasSSE2()", CCAssignToReg<[XMM0]>>>,
103 CCDelegateTo<RetCC_X86Common>
106 // X86-64 C return-value convention.
107 def RetCC_X86_64_C : CallingConv<[
108 // The X86-64 calling convention always returns FP values in XMM0.
109 CCMatchType<[f32], CCAssignToReg<[XMM0]>>,
110 CCMatchType<[f64], CCAssignToReg<[XMM0]>>,
111 CCDelegateTo<RetCC_X86Common>
116 // This is the root return-value convention for the X86-32 backend.
117 def RetCC_X86_32 : CallingConv<[
118 // If FastCC, use RetCC_X86_32_Fast.
119 CCMatchIfCC<"CallingConv::Fast", CCDelegateTo<RetCC_X86_32_Fast>>,
120 // Otherwise, use RetCC_X86_32_C.
121 CCDelegateTo<RetCC_X86_32_C>
124 // This is the root return-value convention for the X86-64 backend.
125 def RetCC_X86_64 : CallingConv<[
126 // Always just the same as C calling conv for X86-64.
127 CCDelegateTo<RetCC_X86_64_C>
132 //===----------------------------------------------------------------------===//
133 // Argument Calling Conventions
134 //===----------------------------------------------------------------------===//
137 def CC_X86_64_C : CallingConv<[
138 // Promote i8/i16 arguments to i32.
139 CCMatchType<[i8, i16], CCPromoteToType<i32>>,
141 // The first 6 integer arguments are passed in integer registers.
142 CCMatchType<[i32], CCAssignToReg<[EDI, ESI, EDX, ECX, R8D, R9D]>>,
143 CCMatchType<[i64], CCAssignToReg<[RDI, RSI, RDX, RCX, R8 , R9 ]>>,
145 // The first 8 FP/Vector arguments are passed in XMM registers.
146 CCMatchType<[f32, f64, v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
147 CCAssignToReg<[XMM0, XMM1, XMM2, XMM3, XMM4, XMM5, XMM6, XMM7]>>,
149 // Integer/FP values get stored in stack slots that are 8 bytes in size and
150 // 8-byte aligned if there are no more registers to hold them.
151 CCMatchType<[i32, i64, f32, f64], CCAssignToStack<8, 8>>,
153 // Vectors get 16-byte stack slots that are 16-byte aligned.
154 CCMatchType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
155 CCAssignToStack<16, 16>>