From 0f7ccd279dc65682899a6cdb112068f512bc0246 Mon Sep 17 00:00:00 2001
From: Chad Rosier <mcrosier@apple.com>
Date: Tue, 19 Mar 2013 21:12:14 +0000
Subject: [PATCH] [ms-inline asm] Remove the brackets from X86Operand in the
 IR. These will be added back in by X86AsmPrinter::printIntelMemReference()
 during codegen. Previously, this following example

  void t() {
    int i;
    __asm mov eax, [i]
  }

would generate the below assembly

  mov eax, dword ptr [[eax]]

which resulted in a fatal error when compiling.  Test case coming on the
clang side.
rdar://13444264

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177440 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/MC/MCParser/AsmParser.cpp | 27 +++++++++++++++++++--------
 1 file changed, 19 insertions(+), 8 deletions(-)

diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index 8f754a4be9f..9eab076ee5c 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -4181,24 +4181,31 @@ AsmParser::parseMSInlineAsm(void *AsmLoc, std::string &AsmString,
   std::string AsmStringIR;
   AsmRewriteKind PrevKind = AOK_Imm;
   raw_string_ostream OS(AsmStringIR);
-  const char *Start = SrcMgr.getMemoryBuffer(0)->getBufferStart();
+  const char *AsmStart = SrcMgr.getMemoryBuffer(0)->getBufferStart();
+  const char *AsmEnd = SrcMgr.getMemoryBuffer(0)->getBufferEnd();
   array_pod_sort(AsmStrRewrites.begin(), AsmStrRewrites.end(), RewritesSort);
   for (SmallVectorImpl<AsmRewrite>::iterator I = AsmStrRewrites.begin(),
                                              E = AsmStrRewrites.end();
        I != E; ++I) {
     const char *Loc = (*I).Loc.getPointer();
-    assert(Loc >= Start && "Expected Loc to be at or after Start!");
+    assert(Loc >= AsmStart && "Expected Loc to be at or after Start!");
 
     unsigned AdditionalSkip = 0;
     AsmRewriteKind Kind = (*I).Kind;
 
     // Emit everything up to the immediate/expression.
-    OS << StringRef(Start, Loc - Start);
+    unsigned Len = Loc - AsmStart;
+    if (Len) {
+      // For Input/Output operands we need to remove the brackets, if present.
+      if ((Kind == AOK_Input || Kind == AOK_Output) && Loc[-1] == '[')
+        --Len;
+      OS << StringRef(AsmStart, Len);
+    }
     PrevKind = Kind;
 
     // Skip the original expression.
     if (Kind == AOK_Skip) {
-      Start = Loc + (*I).Len;
+      AsmStart = Loc + (*I).Len;
       continue;
     }
 
@@ -4247,13 +4254,17 @@ AsmParser::parseMSInlineAsm(void *AsmLoc, std::string &AsmString,
     }
 
     // Skip the original expression.
-    Start = Loc + (*I).Len + AdditionalSkip;
+    AsmStart = Loc + (*I).Len + AdditionalSkip;
+
+    // For Input/Output operands we need to remove the brackets, if present.
+    if ((Kind == AOK_Input || Kind == AOK_Output) && AsmStart != AsmEnd &&
+        *AsmStart == ']')
+      ++AsmStart;
   }
 
   // Emit the remainder of the asm string.
-  const char *AsmEnd = SrcMgr.getMemoryBuffer(0)->getBufferEnd();
-  if (Start != AsmEnd)
-    OS << StringRef(Start, AsmEnd - Start);
+  if (AsmStart != AsmEnd)
+    OS << StringRef(AsmStart, AsmEnd - AsmStart);
 
   AsmString = OS.str();
   return false;
-- 
2.34.1