1//===- WebAssemblyInstrControl.td-WebAssembly control-flow ------*- tablegen -*-
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9///
10/// \file
11/// \brief WebAssembly control-flow code-gen constructs.
12///
13//===----------------------------------------------------------------------===//
14
15/*
16 * TODO(jfb): Add the following.
17 *
18 * block: a fixed-length sequence of statements
19 * if: if statement
20 * do_while: do while statement, basically a loop with a conditional branch
21 * forever: infinite loop statement (like while (1)), basically an unconditional
22 *          branch (back to the top of the loop)
23 * continue: continue to start of nested loop
24 * break: break to end from nested loop or block
25 * switch: switch statement with fallthrough
26 */
27
28let isBranch = 1, isTerminator = 1, hasCtrlDep = 1 in {
29def BRIF : I<(outs), (ins bb_op:$dst, I32:$a),
30             [(brcond I32:$a, bb:$dst)]>;
31let isBarrier = 1 in {
32def BR   : I<(outs), (ins bb_op:$dst),
33             [(br bb:$dst)]>;
34} // isBarrier = 1
35} // isBranch = 1, isTerminator = 1, hasCtrlDep = 1
36
37// TODO: SelectionDAG's lowering insists on using a pointer as the index for
38// jump tables, so in practice we don't ever use SWITCH_I64 in wasm32 mode
39// currently.
40let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
41def SWITCH_I32 : I<(outs), (ins I32:$index, variable_ops),
42                   [(WebAssemblyswitch I32:$index)]>;
43def SWITCH_I64 : I<(outs), (ins I64:$index, variable_ops),
44                   [(WebAssemblyswitch I64:$index)]>;
45} // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
46
47// Placemarkers to indicate the start of a block or loop scope.
48def BLOCK     : I<(outs), (ins bb_op:$dst), []>;
49def LOOP      : I<(outs), (ins bb_op:$dst), []>;
50
51multiclass RETURN<WebAssemblyRegClass vt> {
52  def RETURN_#vt : I<(outs), (ins vt:$val), [(WebAssemblyreturn vt:$val)]>;
53}
54let isReturn = 1, isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
55  defm : RETURN<I32>;
56  defm : RETURN<I64>;
57  defm : RETURN<F32>;
58  defm : RETURN<F64>;
59  def RETURN_VOID : I<(outs), (ins), [(WebAssemblyreturn)]>;
60} // isReturn = 1, isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
61