WebAssemblyInstrControl.td revision 292915 
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
15let Defs = [ARGUMENTS] in {
16
17let isBranch = 1, isTerminator = 1, hasCtrlDep = 1 in {
18// The condition operand is a boolean value which WebAssembly represents as i32.
19def BR_IF : I<(outs), (ins I32:$cond, bb_op:$dst),
20              [(brcond I32:$cond, bb:$dst)],
21               "br_if   \t$cond, $dst">;
22let isCodeGenOnly = 1 in
23def BR_UNLESS : I<(outs), (ins I32:$cond, bb_op:$dst), [],
24                   "br_unless\t$cond, $dst">;
25let isBarrier = 1 in {
26def BR   : I<(outs), (ins bb_op:$dst),
27             [(br bb:$dst)],
28             "br      \t$dst">;
29} // isBarrier = 1
30} // isBranch = 1, isTerminator = 1, hasCtrlDep = 1
31
32} // Defs = [ARGUMENTS]
33
34def : Pat<(brcond (i32 (setne I32:$cond, 0)), bb:$dst),
35          (BR_IF I32:$cond, bb_op:$dst)>;
36def : Pat<(brcond (i32 (seteq I32:$cond, 0)), bb:$dst),
37          (BR_UNLESS I32:$cond, bb_op:$dst)>;
38
39let Defs = [ARGUMENTS] in {
40
41// TODO: SelectionDAG's lowering insists on using a pointer as the index for
42// jump tables, so in practice we don't ever use TABLESWITCH_I64 in wasm32 mode
43// currently.
44let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
45def TABLESWITCH_I32 : I<(outs), (ins I32:$index, bb_op:$default, variable_ops),
46                        [(WebAssemblytableswitch I32:$index, bb:$default)],
47                        "tableswitch\t$index, $default">;
48def TABLESWITCH_I64 : I<(outs), (ins I64:$index, bb_op:$default, variable_ops),
49                        [(WebAssemblytableswitch I64:$index, bb:$default)],
50                        "tableswitch\t$index, $default">;
51} // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
52
53// Placemarkers to indicate the start of a block or loop scope. These
54// use/clobber EXPR_STACK to prevent them from being moved into the middle of
55// an expression tree.
56let Uses = [EXPR_STACK], Defs = [EXPR_STACK] in {
57def BLOCK     : I<(outs), (ins bb_op:$dst), [], "block   \t$dst">;
58def LOOP      : I<(outs), (ins bb_op:$dst), [], "loop    \t$dst">;
59} // Uses = [EXPR_STACK], Defs = [EXPR_STACK]
60
61// No-op to indicate to the AsmPrinter that a loop ends here, so a
62// basic block label is needed even if it wouldn't otherwise appear so.
63let isTerminator = 1, hasCtrlDep = 1 in
64def LOOP_END : I<(outs), (ins), []>;
65
66multiclass RETURN<WebAssemblyRegClass vt> {
67  def RETURN_#vt : I<(outs), (ins vt:$val), [(WebAssemblyreturn vt:$val)],
68                     "return  \t$val">;
69}
70
71let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
72let isReturn = 1 in {
73  defm : RETURN<I32>;
74  defm : RETURN<I64>;
75  defm : RETURN<F32>;
76  defm : RETURN<F64>;
77  def RETURN_VOID : I<(outs), (ins), [(WebAssemblyreturn)], "return">;
78} // isReturn = 1
79  def UNREACHABLE : I<(outs), (ins), [(trap)], "unreachable">;
80} // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
81
82} // Defs = [ARGUMENTS]
83