[llvm] r193403 - ARM: allow .thumb_func to be separated from symbol definition

[Tim Northover]

Author: tnorthover
Date: Fri Oct 25 07:49:50 2013
New Revision: 193403

URL: http://llvm.org/viewvc/llvm-project?rev=193403&view=rev
Log:
ARM: allow .thumb_func to be separated from symbol definition

When assembling, a .thumb_func directive is supposed to be applicable to the
next symbol definition, even if there are intervening directives. We were
racing ahead to try and find it, and this commit should fix the issue.

Patch by Gabor Ballabas

Modified:
    llvm/trunk/include/llvm/MC/MCTargetAsmParser.h
    llvm/trunk/lib/MC/MCParser/AsmParser.cpp
    llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
    llvm/trunk/test/MC/ARM/elf-thumbfunc.s

Modified: llvm/trunk/include/llvm/MC/MCTargetAsmParser.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCTargetAsmParser.h?rev=193403&r1=193402&r2=193403&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCTargetAsmParser.h (original)
+++ llvm/trunk/include/llvm/MC/MCTargetAsmParser.h Fri Oct 25 07:49:50 2013
@@ -181,6 +181,8 @@ public:
                                             MCContext &Ctx) {
     return 0;
   }
+
+  virtual void onLabelParsed(MCSymbol *Symbol) { };
 };
 
 } // End llvm namespace

Modified: llvm/trunk/lib/MC/MCParser/AsmParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCParser/AsmParser.cpp?rev=193403&r1=193402&r2=193403&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCParser/AsmParser.cpp (original)
+++ llvm/trunk/lib/MC/MCParser/AsmParser.cpp Fri Oct 25 07:49:50 2013
@@ -1262,6 +1262,8 @@ bool AsmParser::parseStatement(ParseStat
       MCGenDwarfLabelEntry::Make(Sym, &getStreamer(), getSourceManager(),
                                  IDLoc);
 
+    getTargetParser().onLabelParsed(Sym);
+
     // Consume any end of statement token, if present, to avoid spurious
     // AddBlankLine calls().
     if (Lexer.is(AsmToken::EndOfStatement)) {

Modified: llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp?rev=193403&r1=193402&r2=193403&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp (original)
+++ llvm/trunk/lib/Target/ARM/AsmParser/ARMAsmParser.cpp Fri Oct 25 07:49:50 2013
@@ -74,6 +74,8 @@ class ARMAsmParser : public MCTargetAsmP
   // Map of register aliases registers via the .req directive.
   StringMap<unsigned> RegisterReqs;
 
+  bool NextSymbolIsThumb;
+
   struct {
     ARMCC::CondCodes Cond;    // Condition for IT block.
     unsigned Mask:4;          // Condition mask for instructions.
@@ -268,6 +270,8 @@ public:
 
     // Not in an ITBlock to start with.
     ITState.CurPosition = ~0U;
+
+    NextSymbolIsThumb = false;
   }
 
   // Implementation of the MCTargetAsmParser interface:
@@ -284,6 +288,8 @@ public:
                                SmallVectorImpl<MCParsedAsmOperand*> &Operands,
                                MCStreamer &Out, unsigned &ErrorInfo,
                                bool MatchingInlineAsm);
+  void onLabelParsed(MCSymbol *Symbol);
+
 };
 } // end anonymous namespace
 
@@ -7837,13 +7843,18 @@ bool ARMAsmParser::parseDirectiveARM(SML
   return false;
 }
 
+void ARMAsmParser::onLabelParsed(MCSymbol *Symbol) {
+  if (NextSymbolIsThumb) {
+    getParser().getStreamer().EmitThumbFunc(Symbol);
+    NextSymbolIsThumb = false;
+  }
+}
+
 /// parseDirectiveThumbFunc
 ///  ::= .thumbfunc symbol_name
 bool ARMAsmParser::parseDirectiveThumbFunc(SMLoc L) {
   const MCAsmInfo *MAI = getParser().getStreamer().getContext().getAsmInfo();
   bool isMachO = MAI->hasSubsectionsViaSymbols();
-  StringRef Name;
-  bool needFuncName = true;
 
   // Darwin asm has (optionally) function name after .thumb_func direction
   // ELF doesn't
@@ -7852,29 +7863,19 @@ bool ARMAsmParser::parseDirectiveThumbFu
     if (Tok.isNot(AsmToken::EndOfStatement)) {
       if (Tok.isNot(AsmToken::Identifier) && Tok.isNot(AsmToken::String))
         return Error(L, "unexpected token in .thumb_func directive");
-      Name = Tok.getIdentifier();
+      MCSymbol *Func =
+          getParser().getContext().GetOrCreateSymbol(Tok.getIdentifier());
+      getParser().getStreamer().EmitThumbFunc(Func);
       Parser.Lex(); // Consume the identifier token.
-      needFuncName = false;
+      return false;
     }
   }
 
   if (getLexer().isNot(AsmToken::EndOfStatement))
     return Error(L, "unexpected token in directive");
 
-  // Eat the end of statement and any blank lines that follow.
-  while (getLexer().is(AsmToken::EndOfStatement))
-    Parser.Lex();
-
-  // FIXME: assuming function name will be the line following .thumb_func
-  // We really should be checking the next symbol definition even if there's
-  // stuff in between.
-  if (needFuncName) {
-    Name = Parser.getTok().getIdentifier();
-  }
+  NextSymbolIsThumb = true;
 
-  // Mark symbol as a thumb symbol.
-  MCSymbol *Func = getParser().getContext().GetOrCreateSymbol(Name);
-  getParser().getStreamer().EmitThumbFunc(Func);
   return false;
 }
 

Modified: llvm/trunk/test/MC/ARM/elf-thumbfunc.s
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/MC/ARM/elf-thumbfunc.s?rev=193403&r1=193402&r2=193403&view=diff
==============================================================================
--- llvm/trunk/test/MC/ARM/elf-thumbfunc.s (original)
+++ llvm/trunk/test/MC/ARM/elf-thumbfunc.s Fri Oct 25 07:49:50 2013
@@ -5,9 +5,9 @@
 	.text
 	.globl	foo
 	.align	2
-	.type	foo,%function
 	.code	16
 	.thumb_func
+	.type	foo,%function
 foo:
 	bx	lr