commit 02ecd43c63653f09fa3580170bdf43c572a4096d
author Michael Zuckerman <Michael.zuckerman@intel.com> Sun Dec 13 17:07:23 2015 +0000
committer Michael Zuckerman <Michael.zuckerman@intel.com> Sun Dec 13 17:07:23 2015 +0000
tree 241e83d7aabdb1fb8e2dbbaa4a8a722482304609
parent c00e65aa893c45814bf2186de56b7e0f2d418a5c

[X86][inline asm] support even directive 

The .even directive aligns content to an evan-numbered address.

In at&t syntax .even 
In Microsoft syntax even (without the dot).

Differential Revision: http://reviews.llvm.org/D15413

llvm-svn: 255462

llvm/lib/MC/MCParser/AsmParser.cpp

diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index 61f7d74..646cbb4 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -1714,6 +1714,8 @@
   if (ParsingInlineAsm && (IDVal == "align" || IDVal == "ALIGN"))
     return parseDirectiveMSAlign(IDLoc, Info);
 
+  if (ParsingInlineAsm && (IDVal == "even"))
+    Info.AsmRewrites->emplace_back(AOK_EVEN, IDLoc, 4);
   checkForValidSection();
 
   // Canonicalize the opcode to lower case.
@@ -4863,6 +4865,9 @@
       AdditionalSkip = (Val < 4) ? 2 : Val < 7 ? 3 : 4;
       break;
     }
+    case AOK_EVEN:
+      OS << ".even";
+      break;
     case AOK_DotOperator:
       // Insert the dot if the user omitted it.
       OS.flush();

llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp

diff --git a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
index f2efefd..4d36f1f 100644
--- a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -26,6 +26,7 @@
 #include "llvm/MC/MCParser/MCAsmParser.h"
 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
 #include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCSection.h"
 #include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/MC/MCSymbol.h"
@@ -714,6 +715,7 @@
                         SMLoc End, unsigned Size, StringRef Identifier,
                         InlineAsmIdentifierInfo &Info);
 
+  bool parseDirectiveEven(SMLoc L);
   bool ParseDirectiveWord(unsigned Size, SMLoc L);
   bool ParseDirectiveCode(StringRef IDVal, SMLoc L);
 
@@ -2844,10 +2846,29 @@
                                            "a '%' prefix in .intel_syntax");
     }
     return false;
-  }
+  } else if (IDVal == ".even")
+    return parseDirectiveEven(DirectiveID.getLoc());
   return true;
 }
 
+/// parseDirectiveEven
+///  ::= .even
+bool X86AsmParser::parseDirectiveEven(SMLoc L) {
+  const MCSection *Section = getStreamer().getCurrentSection().first;
+  if (getLexer().isNot(AsmToken::EndOfStatement)) {
+    TokError("unexpected token in directive");
+    return false;  
+  }
+  if (!Section) {
+    getStreamer().InitSections(false);
+    Section = getStreamer().getCurrentSection().first;
+  }
+  if (Section->UseCodeAlign())
+    getStreamer().EmitCodeAlignment(2, 0);
+  else
+    getStreamer().EmitValueToAlignment(2, 0, 1, 0);
+  return false;
+}
 /// ParseDirectiveWord
 ///  ::= .word [ expression (, expression)* ]
 bool X86AsmParser::ParseDirectiveWord(unsigned Size, SMLoc L) {