[llvm] r231760 - Fix a stack overflow in the assembler when checking that GEPs must be over sized types.

[Owen Anderson]

Author: resistor
Date: Tue Mar 10 01:34:57 2015
New Revision: 231760

URL: http://llvm.org/viewvc/llvm-project?rev=231760&view=rev
Log:
Fix a stack overflow in the assembler when checking that GEPs must be over sized types.

We failed to use a marking set to properly handle recursive types, which caused use
to recurse infinitely and eventually overflow the stack.

Added:
    llvm/trunk/test/Assembler/unsized-recursive-type.ll
Modified:
    llvm/trunk/lib/AsmParser/LLParser.cpp

Modified: llvm/trunk/lib/AsmParser/LLParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/AsmParser/LLParser.cpp?rev=231760&r1=231759&r2=231760&view=diff
==============================================================================
--- llvm/trunk/lib/AsmParser/LLParser.cpp (original)
+++ llvm/trunk/lib/AsmParser/LLParser.cpp Tue Mar 10 01:34:57 2015
@@ -2810,7 +2810,9 @@ bool LLParser::ParseValID(ValID &ID, Per
         }
       }
 
-      if (!Indices.empty() && !BasePointerType->getElementType()->isSized())
+      SmallPtrSet<const Type*, 4> Visited;
+      if (!Indices.empty() &&
+          !BasePointerType->getElementType()->isSized(&Visited))
         return Error(ID.Loc, "base element of getelementptr must be sized");
 
       if (!GetElementPtrInst::getIndexedType(Elts[0]->getType(), Indices))
@@ -5496,7 +5498,9 @@ int LLParser::ParseGetElementPtr(Instruc
     Indices.push_back(Val);
   }
 
-  if (!Indices.empty() && !BasePointerType->getElementType()->isSized())
+  SmallPtrSet<const Type*, 4> Visited;
+  if (!Indices.empty() &&
+      !BasePointerType->getElementType()->isSized(&Visited))
     return Error(Loc, "base element of getelementptr must be sized");
 
   if (!GetElementPtrInst::getIndexedType(BaseType, Indices))

Added: llvm/trunk/test/Assembler/unsized-recursive-type.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Assembler/unsized-recursive-type.ll?rev=231760&view=auto
==============================================================================
--- llvm/trunk/test/Assembler/unsized-recursive-type.ll (added)
+++ llvm/trunk/test/Assembler/unsized-recursive-type.ll Tue Mar 10 01:34:57 2015
@@ -0,0 +1,9 @@
+; RUN: not llvm-as < %s 2>&1 | FileCheck %s
+
+; CHECK: base element of getelementptr must be sized
+
+%myTy = type { %myTy }
+define void @foo(%myTy* %p){
+  %0 = getelementptr %myTy, %myTy* %p, i32 0
+  ret void
+}