WebAssemblyInstrControl.td
7.19 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
//===- WebAssemblyInstrControl.td-WebAssembly control-flow ------*- tablegen -*-
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// WebAssembly control-flow code-gen constructs.
///
//===----------------------------------------------------------------------===//
let isBranch = 1, isTerminator = 1, hasCtrlDep = 1 in {
// The condition operand is a boolean value which WebAssembly represents as i32.
defm BR_IF : I<(outs), (ins bb_op:$dst, I32:$cond),
(outs), (ins bb_op:$dst),
[(brcond I32:$cond, bb:$dst)],
"br_if \t$dst, $cond", "br_if \t$dst", 0x0d>;
let isCodeGenOnly = 1 in
defm BR_UNLESS : I<(outs), (ins bb_op:$dst, I32:$cond),
(outs), (ins bb_op:$dst), []>;
let isBarrier = 1 in
defm BR : NRI<(outs), (ins bb_op:$dst),
[(br bb:$dst)],
"br \t$dst", 0x0c>;
} // isBranch = 1, isTerminator = 1, hasCtrlDep = 1
def : Pat<(brcond (i32 (setne I32:$cond, 0)), bb:$dst),
(BR_IF bb_op:$dst, I32:$cond)>;
def : Pat<(brcond (i32 (seteq I32:$cond, 0)), bb:$dst),
(BR_UNLESS bb_op:$dst, I32:$cond)>;
// A list of branch targets enclosed in {} and separated by comma.
// Used by br_table only.
def BrListAsmOperand : AsmOperandClass { let Name = "BrList"; }
let OperandNamespace = "WebAssembly", OperandType = "OPERAND_BRLIST" in
def brlist : Operand<i32> {
let ParserMatchClass = BrListAsmOperand;
let PrintMethod = "printBrList";
}
// TODO: SelectionDAG's lowering insists on using a pointer as the index for
// jump tables, so in practice we don't ever use BR_TABLE_I64 in wasm32 mode
// currently.
let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
defm BR_TABLE_I32 : I<(outs), (ins I32:$index, variable_ops),
(outs), (ins brlist:$brl),
[(WebAssemblybr_table I32:$index)],
"br_table \t$index", "br_table \t$brl",
0x0e>;
defm BR_TABLE_I64 : I<(outs), (ins I64:$index, variable_ops),
(outs), (ins brlist:$brl),
[(WebAssemblybr_table I64:$index)],
"br_table \t$index", "br_table \t$brl",
0x0e>;
} // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
// This is technically a control-flow instruction, since all it affects is the
// IP.
defm NOP : NRI<(outs), (ins), [], "nop", 0x01>;
// Placemarkers to indicate the start or end of a block or loop scope.
// These use/clobber VALUE_STACK to prevent them from being moved into the
// middle of an expression tree.
let Uses = [VALUE_STACK], Defs = [VALUE_STACK] in {
defm BLOCK : NRI<(outs), (ins Signature:$sig), [], "block \t$sig", 0x02>;
defm LOOP : NRI<(outs), (ins Signature:$sig), [], "loop \t$sig", 0x03>;
defm IF : I<(outs), (ins Signature:$sig, I32:$cond),
(outs), (ins Signature:$sig),
[], "if \t$sig, $cond", "if \t$sig", 0x04>;
defm ELSE : NRI<(outs), (ins), [], "else", 0x05>;
// END_BLOCK, END_LOOP, END_IF and END_FUNCTION are represented with the same
// opcode in wasm.
defm END_BLOCK : NRI<(outs), (ins), [], "end_block", 0x0b>;
defm END_LOOP : NRI<(outs), (ins), [], "end_loop", 0x0b>;
defm END_IF : NRI<(outs), (ins), [], "end_if", 0x0b>;
// Generic instruction, for disassembler.
let IsCanonical = 1 in
defm END : NRI<(outs), (ins), [], "end", 0x0b>;
let isTerminator = 1, isBarrier = 1 in
defm END_FUNCTION : NRI<(outs), (ins), [], "end_function", 0x0b>;
} // Uses = [VALUE_STACK], Defs = [VALUE_STACK]
let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
let isReturn = 1 in {
defm RETURN : I<(outs), (ins variable_ops), (outs), (ins),
[(WebAssemblyreturn)],
"return", "return", 0x0f>;
// Equivalent to RETURN, for use at the end of a function when wasm
// semantics return by falling off the end of the block.
let isCodeGenOnly = 1 in
defm FALLTHROUGH_RETURN : I<(outs), (ins variable_ops), (outs), (ins), []>;
} // isReturn = 1
defm UNREACHABLE : NRI<(outs), (ins), [(trap)], "unreachable", 0x00>;
} // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
//===----------------------------------------------------------------------===//
// Exception handling instructions
//===----------------------------------------------------------------------===//
let Predicates = [HasExceptionHandling] in {
// Throwing an exception: throw / rethrow
let isTerminator = 1, hasCtrlDep = 1, isBarrier = 1 in {
defm THROW : I<(outs), (ins event_op:$tag, variable_ops),
(outs), (ins event_op:$tag),
[(WebAssemblythrow (WebAssemblywrapper texternalsym:$tag))],
"throw \t$tag", "throw \t$tag", 0x08>;
defm RETHROW : I<(outs), (ins EXNREF:$exn), (outs), (ins), [],
"rethrow \t$exn", "rethrow", 0x09>;
// Pseudo instruction to be the lowering target of int_wasm_rethrow_in_catch
// intrinsic. Will be converted to the real rethrow instruction later.
let isPseudo = 1 in
defm RETHROW_IN_CATCH : NRI<(outs), (ins), [(int_wasm_rethrow_in_catch)],
"rethrow_in_catch", 0>;
} // isTerminator = 1, hasCtrlDep = 1, isBarrier = 1
// Region within which an exception is caught: try / end_try
let Uses = [VALUE_STACK], Defs = [VALUE_STACK] in {
defm TRY : NRI<(outs), (ins Signature:$sig), [], "try \t$sig", 0x06>;
defm END_TRY : NRI<(outs), (ins), [], "end_try", 0x0b>;
} // Uses = [VALUE_STACK], Defs = [VALUE_STACK]
// Catching an exception: catch / extract_exception
let hasCtrlDep = 1, hasSideEffects = 1 in
defm CATCH : I<(outs EXNREF:$dst), (ins), (outs), (ins), [],
"catch \t$dst", "catch", 0x07>;
// Querying / extracing exception: br_on_exn
// br_on_exn queries an exnref to see if it matches the corresponding exception
// tag index. If true it branches to the given label and pushes the
// corresponding argument values of the exception onto the stack.
let isBranch = 1, isTerminator = 1, hasCtrlDep = 1 in
defm BR_ON_EXN : I<(outs), (ins bb_op:$dst, event_op:$tag, EXNREF:$exn),
(outs), (ins bb_op:$dst, event_op:$tag), [],
"br_on_exn \t$dst, $tag, $exn", "br_on_exn \t$dst, $tag",
0x0a>;
// This is a pseudo instruction that simulates popping a value from stack, which
// has been pushed by br_on_exn
let isCodeGenOnly = 1, hasSideEffects = 1 in
defm EXTRACT_EXCEPTION_I32 : NRI<(outs I32:$dst), (ins),
[(set I32:$dst, (int_wasm_extract_exception))],
"extract_exception\t$dst">;
// Pseudo instructions: cleanupret / catchret
let isTerminator = 1, hasSideEffects = 1, isBarrier = 1, hasCtrlDep = 1,
isPseudo = 1, isEHScopeReturn = 1 in {
defm CLEANUPRET : NRI<(outs), (ins), [(cleanupret)], "cleanupret", 0>;
defm CATCHRET : NRI<(outs), (ins bb_op:$dst, bb_op:$from),
[(catchret bb:$dst, bb:$from)], "catchret", 0>;
} // isTerminator = 1, hasSideEffects = 1, isBarrier = 1, hasCtrlDep = 1,
// isPseudo = 1, isEHScopeReturn = 1
} // Predicates = [HasExceptionHandling]