1 //===-- MCAsmParser.cpp - Abstract Asm Parser Interface -------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/MC/MCParser/MCAsmParser.h"
10 #include "llvm/ADT/StringRef.h"
11 #include "llvm/ADT/Twine.h"
12 #include "llvm/Config/llvm-config.h"
13 #include "llvm/MC/MCParser/MCAsmLexer.h"
14 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
15 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
16 #include "llvm/Support/CommandLine.h"
17 #include "llvm/Support/Debug.h"
18 #include "llvm/Support/SMLoc.h"
19 #include "llvm/Support/raw_ostream.h"
20 #include <cassert>
21 
22 using namespace llvm;
23 
24 namespace llvm {
25 cl::opt<unsigned> AsmMacroMaxNestingDepth(
26     "asm-macro-max-nesting-depth", cl::init(20), cl::Hidden,
27     cl::desc("The maximum nesting depth allowed for assembly macros."));
28 }
29 
30 MCAsmParser::MCAsmParser() = default;
31 
32 MCAsmParser::~MCAsmParser() = default;
33 
34 void MCAsmParser::setTargetParser(MCTargetAsmParser &P) {
35   assert(!TargetParser && "Target parser is already initialized!");
36   TargetParser = &P;
37   TargetParser->Initialize(*this);
38 }
39 
40 const AsmToken &MCAsmParser::getTok() const {
41   return getLexer().getTok();
42 }
43 
44 bool MCAsmParser::parseTokenLoc(SMLoc &Loc) {
45   Loc = getTok().getLoc();
46   return false;
47 }
48 
49 bool MCAsmParser::parseEOL() {
50   if (getTok().getKind() != AsmToken::EndOfStatement)
51     return Error(getTok().getLoc(), "expected newline");
52   Lex();
53   return false;
54 }
55 
56 bool MCAsmParser::parseEOL(const Twine &Msg) {
57   if (getTok().getKind() != AsmToken::EndOfStatement)
58     return Error(getTok().getLoc(), Msg);
59   Lex();
60   return false;
61 }
62 
63 bool MCAsmParser::parseToken(AsmToken::TokenKind T, const Twine &Msg) {
64   if (T == AsmToken::EndOfStatement)
65     return parseEOL(Msg);
66   if (getTok().getKind() != T)
67     return Error(getTok().getLoc(), Msg);
68   Lex();
69   return false;
70 }
71 
72 bool MCAsmParser::parseIntToken(int64_t &V, const Twine &Msg) {
73   if (getTok().getKind() != AsmToken::Integer)
74     return TokError(Msg);
75   V = getTok().getIntVal();
76   Lex();
77   return false;
78 }
79 
80 bool MCAsmParser::parseOptionalToken(AsmToken::TokenKind T) {
81   bool Present = (getTok().getKind() == T);
82   if (Present)
83     parseToken(T);
84   return Present;
85 }
86 
87 bool MCAsmParser::check(bool P, const Twine &Msg) {
88   return check(P, getTok().getLoc(), Msg);
89 }
90 
91 bool MCAsmParser::check(bool P, SMLoc Loc, const Twine &Msg) {
92   if (P)
93     return Error(Loc, Msg);
94   return false;
95 }
96 
97 bool MCAsmParser::TokError(const Twine &Msg, SMRange Range) {
98   return Error(getLexer().getLoc(), Msg, Range);
99 }
100 
101 bool MCAsmParser::Error(SMLoc L, const Twine &Msg, SMRange Range) {
102 
103   MCPendingError PErr;
104   PErr.Loc = L;
105   Msg.toVector(PErr.Msg);
106   PErr.Range = Range;
107   PendingErrors.push_back(PErr);
108 
109   // If we threw this parsing error after a lexing error, this should
110   // supercede the lexing error and so we remove it from the Lexer
111   // before it can propagate
112   if (getTok().is(AsmToken::Error))
113     getLexer().Lex();
114   return true;
115 }
116 
117 bool MCAsmParser::addErrorSuffix(const Twine &Suffix) {
118   // Make sure lexing errors have propagated to the parser.
119   if (getTok().is(AsmToken::Error))
120     Lex();
121   for (auto &PErr : PendingErrors)
122     Suffix.toVector(PErr.Msg);
123   return true;
124 }
125 
126 bool MCAsmParser::parseMany(function_ref<bool()> parseOne, bool hasComma) {
127   if (parseOptionalToken(AsmToken::EndOfStatement))
128     return false;
129   while (true) {
130     if (parseOne())
131       return true;
132     if (parseOptionalToken(AsmToken::EndOfStatement))
133       return false;
134     if (hasComma && parseToken(AsmToken::Comma))
135       return true;
136   }
137   return false;
138 }
139 
140 bool MCAsmParser::parseExpression(const MCExpr *&Res) {
141   SMLoc L;
142   return parseExpression(Res, L);
143 }
144 
145 bool MCAsmParser::parseGNUAttribute(SMLoc L, int64_t &Tag,
146                                     int64_t &IntegerValue) {
147   // Parse a .gnu_attribute with numerical tag and value.
148   StringRef S(L.getPointer());
149   SMLoc TagLoc;
150   TagLoc = getTok().getLoc();
151   const AsmToken &Tok = getTok();
152   if (Tok.isNot(AsmToken::Integer))
153     return false;
154   Tag = Tok.getIntVal();
155   Lex(); // Eat the Tag
156   Lex(); // Eat the comma
157   if (Tok.isNot(AsmToken::Integer))
158     return false;
159   IntegerValue = Tok.getIntVal();
160   Lex(); // Eat the IntegerValue
161   return true;
162 }
163 
164 void MCParsedAsmOperand::dump() const {
165   // Cannot completely remove virtual function even in release mode.
166 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
167   dbgs() << "  " << *this;
168 #endif
169 }
170