From 15e9b33678bc112658d6d1e47ad7fc59884d1d8b Mon Sep 17 00:00:00 2001
From: Eli Friedman <eli.friedman@gmail.com>
Date: Mon, 22 Oct 2012 20:50:25 +0000
Subject: [PATCH] [ms-inline asm] Don't rewrite out parts of an inline-asm
 skipped by .if 0 and friends. It's unnecessary and makes the generated
 assembly less faithful to the original source.

llvm-svn: 166440
---
 llvm/lib/MC/MCParser/AsmParser.cpp | 25 +------------------------
 1 file changed, 1 insertion(+), 24 deletions(-)

diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index f22b275..2f63fd4 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -3579,8 +3579,7 @@ enum AsmRewriteKind {
    AOK_Imm,
    AOK_Input,
    AOK_Output,
-   AOK_SizeDirective,
-   AOK_Skip
+   AOK_SizeDirective
 };
 
 struct AsmRewrite {
@@ -3620,24 +3619,9 @@ bool AsmParser::ParseMSInlineAsm(void *AsmLoc, std::string &AsmString,
     // Clear the opcode.
     setOpcode(~0x0);
 
-    // Save the conditional ignore state of the parser prior to parsing the statement.
-    bool PreParseCondStateIgnore = TheCondState.Ignore;
-
-    // Save the starting point of this statement in case we need to skip it.
-    SMLoc Start = getLexer().getLoc();
-
     if (ParseStatement())
       return true;
 
-    // If PreParseCondStateIgnore is false, but TheCondState.Ignore is true, then we
-    // just parsed a directive that changed the state to ignore.  Don't skip 
-    // emitting this directive.
-    if (PreParseCondStateIgnore && TheCondState.Ignore) {
-      unsigned Len = getLexer().getLoc().getPointer() - Start.getPointer();
-      AsmStrRewrites.push_back(AsmRewrite(AOK_Skip, Start, Len));
-      continue;
-    }
-
     if (isInstruction()) {
       const MCInstrDesc &Desc = MII->get(getOpcode());
 
@@ -3743,15 +3727,8 @@ bool AsmParser::ParseMSInlineAsm(void *AsmLoc, std::string &AsmString,
       OS << StringRef(Start, Loc - Start);
     PrevKind = Kind;
 
-    // Skip the original expression.
-    if (Kind == AOK_Skip) {
-      Start = Loc + (*I).Len;
-      continue;
-    }
-
     // Rewrite expressions in $N notation.
     switch (Kind) {
-    default: break;
     case AOK_Imm:
       OS << Twine("$$") + StringRef(Loc, (*I).Len);
       break;
-- 
2.7.4