xref: /freebsd-src/contrib/llvm-project/llvm/lib/Target/BPF/BPFCallingConv.td (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
1*0b57cec5SDimitry Andric//===-- BPFCallingConv.td - Calling Conventions BPF --------*- tablegen -*-===//
2*0b57cec5SDimitry Andric//
3*0b57cec5SDimitry Andric// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*0b57cec5SDimitry Andric// See https://llvm.org/LICENSE.txt for license information.
5*0b57cec5SDimitry Andric// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*0b57cec5SDimitry Andric//
7*0b57cec5SDimitry Andric//===----------------------------------------------------------------------===//
8*0b57cec5SDimitry Andric//
9*0b57cec5SDimitry Andric// This describes the calling conventions for the BPF architecture.
10*0b57cec5SDimitry Andric//
11*0b57cec5SDimitry Andric//===----------------------------------------------------------------------===//
12*0b57cec5SDimitry Andric
13*0b57cec5SDimitry Andric// BPF 64-bit C return-value convention.
14*0b57cec5SDimitry Andricdef RetCC_BPF64 : CallingConv<[CCIfType<[i64], CCAssignToReg<[R0]>>]>;
15*0b57cec5SDimitry Andric
16*0b57cec5SDimitry Andric// BPF 64-bit C Calling convention.
17*0b57cec5SDimitry Andricdef CC_BPF64 : CallingConv<[
18*0b57cec5SDimitry Andric  // Promote i8/i16/i32 args to i64
19*0b57cec5SDimitry Andric  CCIfType<[ i8, i16, i32 ], CCPromoteToType<i64>>,
20*0b57cec5SDimitry Andric
21*0b57cec5SDimitry Andric  // All arguments get passed in integer registers if there is space.
22*0b57cec5SDimitry Andric  CCIfType<[i64], CCAssignToReg<[ R1, R2, R3, R4, R5 ]>>,
23*0b57cec5SDimitry Andric
24*0b57cec5SDimitry Andric  // Could be assigned to the stack in 8-byte aligned units, but unsupported
25*0b57cec5SDimitry Andric  CCAssignToStack<8, 8>
26*0b57cec5SDimitry Andric]>;
27*0b57cec5SDimitry Andric
28*0b57cec5SDimitry Andric// Return-value convention when -mattr=+alu32 enabled
29*0b57cec5SDimitry Andricdef RetCC_BPF32 : CallingConv<[
30*0b57cec5SDimitry Andric  CCIfType<[i32], CCAssignToRegWithShadow<[W0], [R0]>>,
31*0b57cec5SDimitry Andric  CCIfType<[i64], CCAssignToRegWithShadow<[R0], [W0]>>
32*0b57cec5SDimitry Andric]>;
33*0b57cec5SDimitry Andric
34*0b57cec5SDimitry Andric// Calling convention when -mattr=+alu32 enabled
35*0b57cec5SDimitry Andricdef CC_BPF32 : CallingConv<[
36*0b57cec5SDimitry Andric  // Promote i8/i16/i32 args to i64
37*0b57cec5SDimitry Andric  CCIfType<[i32], CCAssignToRegWithShadow<[W1, W2, W3, W4, W5],
38*0b57cec5SDimitry Andric                                          [R1, R2, R3, R4, R5]>>,
39*0b57cec5SDimitry Andric
40*0b57cec5SDimitry Andric  // All arguments get passed in integer registers if there is space.
41*0b57cec5SDimitry Andric  CCIfType<[i64], CCAssignToRegWithShadow<[R1, R2, R3, R4, R5],
42*0b57cec5SDimitry Andric                                          [W1, W2, W3, W4, W5]>>,
43*0b57cec5SDimitry Andric
44*0b57cec5SDimitry Andric  // Could be assigned to the stack in 8-byte aligned units, but unsupported
45*0b57cec5SDimitry Andric  CCAssignToStack<8, 8>
46*0b57cec5SDimitry Andric]>;
47*0b57cec5SDimitry Andric
48*0b57cec5SDimitry Andricdef CSR : CalleeSavedRegs<(add R6, R7, R8, R9, R10)>;
49