add support for .zerofill, patch by Kevin Enderby!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75301 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/llvm-mc/AsmParser.cpp b/tools/llvm-mc/AsmParser.cpp
index 65ec962..1d9e1b6 100644
--- a/tools/llvm-mc/AsmParser.cpp
+++ b/tools/llvm-mc/AsmParser.cpp
@@ -524,6 +524,8 @@
return ParseDirectiveComm(/*IsLocal=*/false);
if (!strcmp(IDVal, ".lcomm"))
return ParseDirectiveComm(/*IsLocal=*/true);
+ if (!strcmp(IDVal, ".zerofill"))
+ return ParseDirectiveDarwinZerofill();
Warning(IDLoc, "ignoring directive for now");
EatToEndOfStatement();
@@ -958,3 +960,95 @@
return false;
}
+
+/// ParseDirectiveDarwinZerofill
+/// ::= .zerofill segname , sectname [, identifier , size_expression [
+/// , align_expression ]]
+bool AsmParser::ParseDirectiveDarwinZerofill() {
+ if (Lexer.isNot(asmtok::Identifier))
+ return TokError("expected segment name after '.zerofill' directive");
+ std::string Section = Lexer.getCurStrVal();
+ Lexer.Lex();
+
+ if (Lexer.isNot(asmtok::Comma))
+ return TokError("unexpected token in directive");
+ Section += ',';
+ Lexer.Lex();
+
+ if (Lexer.isNot(asmtok::Identifier))
+ return TokError("expected section name after comma in '.zerofill' "
+ "directive");
+ Section += Lexer.getCurStrVal();
+ Lexer.Lex();
+
+ // FIXME: we will need to tell GetSection() that this is to be created with or
+ // must have the Mach-O section type of S_ZEROFILL. Something like the code
+ // below could be done but for now it is not as EmitZerofill() does not know
+ // how to deal with a section type in the section name like
+ // ParseDirectiveDarwinSection() allows.
+ // Section += ',';
+ // Section += "zerofill";
+
+ // If this is the end of the line all that was wanted was to create the
+ // the section but with no symbol.
+ if (Lexer.is(asmtok::EndOfStatement)) {
+ // Create the zerofill section but no symbol
+ Out.EmitZerofill(Ctx.GetSection(Section.c_str()));
+ return false;
+ }
+
+ if (Lexer.isNot(asmtok::Comma))
+ return TokError("unexpected token in directive");
+ Lexer.Lex();
+
+ if (Lexer.isNot(asmtok::Identifier))
+ return TokError("expected identifier in directive");
+
+ // handle the identifier as the key symbol.
+ SMLoc IDLoc = Lexer.getLoc();
+ MCSymbol *Sym = Ctx.GetOrCreateSymbol(Lexer.getCurStrVal());
+ Lexer.Lex();
+
+ if (Lexer.isNot(asmtok::Comma))
+ return TokError("unexpected token in directive");
+ Lexer.Lex();
+
+ int64_t Size;
+ SMLoc SizeLoc = Lexer.getLoc();
+ if (ParseAbsoluteExpression(Size))
+ return true;
+
+ int64_t Pow2Alignment = 0;
+ SMLoc Pow2AlignmentLoc;
+ if (Lexer.is(asmtok::Comma)) {
+ Lexer.Lex();
+ Pow2AlignmentLoc = Lexer.getLoc();
+ if (ParseAbsoluteExpression(Pow2Alignment))
+ return true;
+ }
+
+ if (Lexer.isNot(asmtok::EndOfStatement))
+ return TokError("unexpected token in '.zerofill' directive");
+
+ Lexer.Lex();
+
+ if (Size < 0)
+ return Error(SizeLoc, "invalid '.zerofill' directive size, can't be less "
+ "than zero");
+
+ // NOTE: The alignment in the directive is a power of 2 value, the assember
+ // may internally end up wanting an alignment in bytes.
+ // FIXME: Diagnose overflow.
+ if (Pow2Alignment < 0)
+ return Error(Pow2AlignmentLoc, "invalid '.zerofill' directive alignment, "
+ "can't be less than zero");
+
+ // TODO: Symbol must be undefined or it is a error to re-defined the symbol
+ if (Sym->getSection() || Ctx.GetSymbolValue(Sym))
+ return Error(IDLoc, "invalid symbol redefinition");
+
+ // Create the zerofill Symbol with Size and Pow2Alignment
+ Out.EmitZerofill(Ctx.GetSection(Section.c_str()), Sym, Size, Pow2Alignment);
+
+ return false;
+}