1 //===- PPCCallingConv.td - Calling Conventions for PowerPC ------*- C++ -*-===//
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 PowerPC 32- and 64-bit
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<PPCSubtarget>().", F), A>;
19 //===----------------------------------------------------------------------===//
20 // Return Value Calling Convention
21 //===----------------------------------------------------------------------===//
23 // Return-value convention for PowerPC
24 def RetCC_PPC : CallingConv<[
25 CCIfType<[i32], CCAssignToReg<[R3, R4, R5, R6, R7, R8, R9, R10]>>,
26 CCIfType<[i64], CCAssignToReg<[X3, X4, X5, X6]>>,
28 CCIfType<[f32], CCAssignToReg<[F1]>>,
29 CCIfType<[f64], CCAssignToReg<[F1, F2]>>,
31 // Vector types are always returned in V2.
32 CCIfType<[v16i8, v8i16, v4i32, v4f32], CCAssignToReg<[V2]>>
36 //===----------------------------------------------------------------------===//
37 // PowerPC Argument Calling Conventions
38 //===----------------------------------------------------------------------===//
40 def CC_PPC : CallingConv<[
41 // The first 8 integer arguments are passed in integer registers.
42 CCIfType<[i32], CCAssignToReg<[R3, R4, R5, R6, R7, R8, R9, R10]>>,
43 CCIfType<[i64], CCAssignToReg<[X3, X4, X5, X6, X7, X8, X9, X10]>>,
45 // Common sub-targets passes FP values in F1 - F13
46 CCIfType<[f32, f64], CCIfSubtarget<"isMachoABI()",
47 CCAssignToReg<[F1, F2, F3, F4, F5, F6, F7, F8,F9,F10,F11,F12,F13]>>>,
48 // ELF32 sub-target pass FP values in F1 - F8.
49 CCIfType<[f32, f64], CCAssignToReg<[F1, F2, F3, F4, F5, F6, F7, F8]>>,
51 // The first 12 Vector arguments are passed in altivec registers.
52 CCIfType<[v16i8, v8i16, v4i32, v4f32],
53 CCAssignToReg<[V2, V3, V4, V5, V6, V7, V8, V9, V10,V11,V12,V13]>>
56 // Integer/FP values get stored in stack slots that are 8 bytes in size and
57 // 8-byte aligned if there are no more registers to hold them.
58 CCIfType<[i32, i64, f32, f64], CCAssignToStack<8, 8>>,
60 // Vectors get 16-byte stack slots that are 16-byte aligned.
61 CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
62 CCAssignToStack<16, 16>>*/
67 //===----------------------------------------------------------------------===//
68 // PowerPC System V Release 4 ABI
69 //===----------------------------------------------------------------------===//
71 // _Complex arguments are never split, thus their two scalars are either
72 // passed both in argument registers or both on the stack. Also _Complex
73 // arguments are always passed in general purpose registers, never in
74 // Floating-point registers or vector registers. Arguments which should go
75 // on the stack are marked with the inreg parameter attribute.
76 // Giving inreg this target-dependent (and counter-intuitive) meaning
77 // simplifies things, because functions calls are not always coming from the
78 // frontend but are also created implicitly e.g. for libcalls. If inreg would
79 // actually mean that the argument is passed in a register, then all places
80 // which create function calls/function definitions implicitly would need to
81 // be aware of this fact and would need to mark arguments accordingly. With
82 // inreg meaning that the argument is passed on the stack, this is not an
83 // issue, except for calls which involve _Complex types.
85 def CC_PPC_SVR4_Common : CallingConv<[
86 // The ABI requires i64 to be passed in two adjacent registers with the first
87 // register having an odd register number.
88 CCIfType<[i32], CCIfSplit<CCCustom<"CC_PPC_SVR4_Custom_AlignArgRegs">>>,
90 // The first 8 integer arguments are passed in integer registers.
91 CCIfType<[i32], CCIf<"!ArgFlags.isInReg()",
92 CCAssignToReg<[R3, R4, R5, R6, R7, R8, R9, R10]>>>,
94 // Make sure the i64 words from a long double are either both passed in
95 // registers or both passed on the stack.
96 CCIfType<[f64], CCIfSplit<CCCustom<"CC_PPC_SVR4_Custom_AlignFPArgRegs">>>,
98 // FP values are passed in F1 - F8.
99 CCIfType<[f32, f64], CCAssignToReg<[F1, F2, F3, F4, F5, F6, F7, F8]>>,
101 // Split arguments have an alignment of 8 bytes on the stack.
102 CCIfType<[i32], CCIfSplit<CCAssignToStack<4, 8>>>,
104 CCIfType<[i32], CCAssignToStack<4, 4>>,
106 // Floats are stored in double precision format, thus they have the same
107 // alignment and size as doubles.
108 CCIfType<[f32,f64], CCAssignToStack<8, 8>>,
110 // Vectors get 16-byte stack slots that are 16-byte aligned.
111 CCIfType<[v16i8, v8i16, v4i32, v4f32], CCAssignToStack<16, 16>>
114 // This calling convention puts vector arguments always on the stack. It is used
115 // to assign vector arguments which belong to the variable portion of the
116 // parameter list of a variable argument function.
117 def CC_PPC_SVR4_VarArg : CallingConv<[
118 CCDelegateTo<CC_PPC_SVR4_Common>
121 // In contrast to CC_PPC_SVR4_VarArg, this calling convention first tries to put
122 // vector arguments in vector registers before putting them on the stack.
123 def CC_PPC_SVR4 : CallingConv<[
124 // The first 12 Vector arguments are passed in AltiVec registers.
125 CCIfType<[v16i8, v8i16, v4i32, v4f32],
126 CCAssignToReg<[V2, V3, V4, V5, V6, V7, V8, V9, V10, V11, V12, V13]>>,
128 CCDelegateTo<CC_PPC_SVR4_Common>
131 // Helper "calling convention" to handle aggregate by value arguments.
132 // Aggregate by value arguments are always placed in the local variable space
133 // of the caller. This calling convention is only used to assign those stack
134 // offsets in the callers stack frame.
136 // Still, the address of the aggregate copy in the callers stack frame is passed
137 // in a GPR (or in the parameter list area if all GPRs are allocated) from the
138 // caller to the callee. The location for the address argument is assigned by
139 // the CC_PPC_SVR4 calling convention.
141 // The only purpose of CC_PPC_SVR4_Custom_Dummy is to skip arguments which are
142 // not passed by value.
144 def CC_PPC_SVR4_ByVal : CallingConv<[
145 CCIfByVal<CCPassByVal<4, 4>>,
147 CCCustom<"CC_PPC_SVR4_Custom_Dummy">