Work-in-progress parsing for ELF .section directive.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108609 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 113 insertions, 5 deletions

diff --git a/lib/MC/MCParser/ELFAsmParser.cpp b/lib/MC/MCParser/ELFAsmParser.cpp
index f870318..340af23 100644
--- a/lib/MC/MCParser/ELFAsmParser.cpp
+++ b/lib/MC/MCParser/ELFAsmParser.cpp
@@ -8,10 +8,11 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/MC/MCParser/MCAsmParserExtension.h"
-#include "llvm/MC/MCSectionELF.h"
+#include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCContext.h"
-#include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCParser/MCAsmLexer.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/MC/MCStreamer.h"
 using namespace llvm;
 
 namespace {
@@ -31,8 +32,10 @@ public:
                                  &ELFAsmParser::ParseSectionDirectiveData));
     Parser.AddDirectiveHandler(this, ".text", MCAsmParser::DirectiveHandler(
                                  &ELFAsmParser::ParseSectionDirectiveText));
+    Parser.AddDirectiveHandler(this, ".section", MCAsmParser::DirectiveHandler(
+                                 &ELFAsmParser::ParseDirectiveSection));
     Parser.AddDirectiveHandler(this, ".size", MCAsmParser::DirectiveHandler(
-                                 &ELFAsmParser::ParseSizeDirective));
+                                 &ELFAsmParser::ParseDirectiveSize));
   }
 
   bool ParseSectionDirectiveData(StringRef, SMLoc) {
@@ -45,7 +48,8 @@ public:
                               MCSectionELF::SHF_EXECINSTR |
                               MCSectionELF::SHF_ALLOC, SectionKind::getText());
   }
-  bool ParseSizeDirective(StringRef, SMLoc);
+  bool ParseDirectiveSection(StringRef, SMLoc);
+  bool ParseDirectiveSize(StringRef, SMLoc);
 };
 
 }
@@ -62,7 +66,7 @@ bool ELFAsmParser::ParseSectionSwitch(StringRef Section, unsigned Type,
   return false;
 }
 
-bool ELFAsmParser::ParseSizeDirective(StringRef, SMLoc) {
+bool ELFAsmParser::ParseDirectiveSize(StringRef, SMLoc) {
   StringRef Name;
   if (getParser().ParseIdentifier(Name))
     return TokError("expected identifier in directive");
@@ -83,6 +87,110 @@ bool ELFAsmParser::ParseSizeDirective(StringRef, SMLoc) {
   return false;
 }
 
+// FIXME: This is a work in progress.
+bool ELFAsmParser::ParseDirectiveSection(StringRef, SMLoc) {
+  StringRef SectionName;
+  // FIXME: This doesn't parse section names like ".note.GNU-stack" correctly.
+  if (getParser().ParseIdentifier(SectionName))
+    return TokError("expected identifier in directive");
+
+  std::string FlagsStr;
+  StringRef TypeName;
+  int64_t Size = 0;
+  if (getLexer().is(AsmToken::Comma)) {
+    Lex();
+
+    if (getLexer().isNot(AsmToken::String))
+      return TokError("expected string in directive");
+
+    FlagsStr = getTok().getStringContents();
+    Lex();
+
+    AsmToken::TokenKind TypeStartToken;
+    if (getContext().getAsmInfo().getCommentString()[0] == '@')
+      TypeStartToken = AsmToken::Percent;
+    else
+      TypeStartToken = AsmToken::At;
+
+    if (getLexer().is(AsmToken::Comma)) {
+      Lex();
+      if (getLexer().is(TypeStartToken)) {
+        Lex();
+        if (getParser().ParseIdentifier(TypeName))
+          return TokError("expected identifier in directive");
+
+        if (getLexer().is(AsmToken::Comma)) {
+          Lex();
+
+          if (getParser().ParseAbsoluteExpression(Size))
+            return true;
+
+          if (Size <= 0)
+            return TokError("section size must be positive");
+        }
+      }
+    }
+  }
+
+  if (getLexer().isNot(AsmToken::EndOfStatement))
+    return TokError("unexpected token in directive");
+
+  unsigned Flags = 0;
+  for (unsigned i = 0; i < FlagsStr.size(); i++) {
+    switch (FlagsStr[i]) {
+    case 'a':
+      Flags |= MCSectionELF::SHF_ALLOC;
+      break;
+    case 'x':
+      Flags |= MCSectionELF::SHF_EXECINSTR;
+      break;
+    case 'w':
+      Flags |= MCSectionELF::SHF_WRITE;
+      break;
+    case 'M':
+      Flags |= MCSectionELF::SHF_MERGE;
+      break;
+    case 'S':
+      Flags |= MCSectionELF::SHF_STRINGS;
+      break;
+    case 'T':
+      Flags |= MCSectionELF::SHF_TLS;
+      break;
+    case 'c':
+      Flags |= MCSectionELF::XCORE_SHF_CP_SECTION;
+      break;
+    case 'd':
+      Flags |= MCSectionELF::XCORE_SHF_DP_SECTION;
+      break;
+    default:
+      return TokError("unknown flag");
+    }
+  }
+
+  unsigned Type = MCSectionELF::SHT_NULL;
+  if (!TypeName.empty()) {
+    if (TypeName == "init_array")
+      Type = MCSectionELF::SHT_INIT_ARRAY;
+    else if (TypeName == "fini_array")
+      Type = MCSectionELF::SHT_FINI_ARRAY;
+    else if (TypeName == "preinit_array")
+      Type = MCSectionELF::SHT_PREINIT_ARRAY;
+    else if (TypeName == "nobits")
+      Type = MCSectionELF::SHT_NOBITS;
+    else if (TypeName == "progbits")
+      Type = MCSectionELF::SHT_PROGBITS;
+    else
+      return TokError("unknown section type");
+  }
+
+  SectionKind Kind = (Flags & MCSectionELF::SHF_EXECINSTR)
+                     ? SectionKind::getText()
+                     : SectionKind::getDataRel();
+  getStreamer().SwitchSection(getContext().getELFSection(SectionName, Type,
+                                                         Flags, Kind, false));
+  return false;
+}
+
 namespace llvm {
 
 MCAsmParserExtension *createELFAsmParser() {