1//===-- BPFCallingConv.td - Calling Conventions BPF --------*- tablegen -*-===//
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// This describes the calling conventions for the BPF architecture.
10//
11//===----------------------------------------------------------------------===//
12
13// BPF 64-bit C return-value convention.
14def RetCC_BPF64 : CallingConv<[CCIfType<[i64], CCAssignToReg<[R0]>>]>;
15
16// BPF 64-bit C Calling convention.
17def CC_BPF64 : CallingConv<[
18  // Promote i8/i16/i32 args to i64
19  CCIfType<[ i8, i16, i32 ], CCPromoteToType<i64>>,
20
21  // All arguments get passed in integer registers if there is space.
22  CCIfType<[i64], CCAssignToReg<[ R1, R2, R3, R4, R5 ]>>,
23
24  // Could be assigned to the stack in 8-byte aligned units, but unsupported
25  CCAssignToStack<8, 8>
26]>;
27
28// Return-value convention when -mattr=+alu32 enabled
29def RetCC_BPF32 : CallingConv<[
30  CCIfType<[i32], CCAssignToRegWithShadow<[W0], [R0]>>,
31  CCIfType<[i64], CCAssignToRegWithShadow<[R0], [W0]>>
32]>;
33
34// Calling convention when -mattr=+alu32 enabled
35def CC_BPF32 : CallingConv<[
36  // Promote i8/i16/i32 args to i64
37  CCIfType<[i32], CCAssignToRegWithShadow<[W1, W2, W3, W4, W5],
38                                          [R1, R2, R3, R4, R5]>>,
39
40  // All arguments get passed in integer registers if there is space.
41  CCIfType<[i64], CCAssignToRegWithShadow<[R1, R2, R3, R4, R5],
42                                          [W1, W2, W3, W4, W5]>>,
43
44  // Could be assigned to the stack in 8-byte aligned units, but unsupported
45  CCAssignToStack<8, 8>
46]>;
47
48def CSR : CalleeSavedRegs<(add R6, R7, R8, R9, R10)>;
49