WebAssemblyInstrFormats.td revision 344779 
1//=- WebAssemblyInstrFormats.td - WebAssembly Instr. Formats -*- 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/// WebAssembly instruction format definitions.
12///
13//===----------------------------------------------------------------------===//
14
15// WebAssembly Instruction Format.
16// We instantiate 2 of these for every actual instruction (register based
17// and stack based), see below.
18class WebAssemblyInst<bits<32> inst, string asmstr, string stack> : StackRel,
19  Instruction {
20  bits<32> Inst = inst; // Instruction encoding.
21  string StackBased = stack;
22  string BaseName = NAME;
23  let Namespace   = "WebAssembly";
24  let Pattern     = [];
25  let AsmString   = asmstr;
26}
27
28// Normal instructions. Default instantiation of a WebAssemblyInst.
29class NI<dag oops, dag iops, list<dag> pattern, string stack,
30         string asmstr = "", bits<32> inst = -1>
31    : WebAssemblyInst<inst, asmstr, stack> {
32  dag OutOperandList = oops;
33  dag InOperandList  = iops;
34  let Pattern        = pattern;
35  let Defs           = [ARGUMENTS];
36}
37
38// Generates both register and stack based versions of one actual instruction.
39// We have 2 sets of operands (oops & iops) for the register and stack
40// based version of this instruction, as well as the corresponding asmstr.
41// The register versions have virtual-register operands which correspond to wasm
42// locals or stack locations. Each use and def of the register corresponds to an
43// implicit local.get / local.set or access of stack operands in wasm. These
44// instructions are used for ISel and all MI passes. The stack versions of the
45// instructions do not have register operands (they implicitly operate on the
46// stack), and local.gets and local.sets are explicit. The register instructions
47// are converted to their corresponding stack instructions before lowering to
48// MC.
49// Every instruction should want to be based on this multi-class to guarantee
50// there is always an equivalent pair of instructions.
51multiclass I<dag oops_r, dag iops_r, dag oops_s, dag iops_s,
52             list<dag> pattern_r, string asmstr_r = "", string asmstr_s = "",
53             bits<32> inst = -1> {
54  let isCodeGenOnly = 1 in
55  def "" : NI<oops_r, iops_r, pattern_r, "false", asmstr_r, inst>;
56  let BaseName = NAME in
57  def _S : NI<oops_s, iops_s, [], "true", asmstr_s, inst>;
58}
59
60// For instructions that have no register ops, so both sets are the same.
61multiclass NRI<dag oops, dag iops, list<dag> pattern, string asmstr = "",
62               bits<32> inst = -1> {
63  defm "": I<oops, iops, oops, iops, pattern, asmstr, asmstr, inst>;
64}
65