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