Adding a collector name attribute to Function in the IR. These

methods are new to Function:

  bool hasCollector() const;
  const std::string &getCollector() const;
  void setCollector(const std::string &);
  void clearCollector();

The assembly representation is as such:

  define void @f() gc "shadow-stack" { ...

The implementation uses an on-the-side table to map Functions to 
collector names, such that there is no overhead. A StringPool is 
further used to unique collector names, which are extremely
likely to be unique per process.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44769 91177308-0d34-0410-b5e6-96231b3b80d8

bindings/ocaml/llvm/llvm.ml

@@ -282,6 +282,8 @@ external is_intrinsic : llvalue -> bool = "llvm_is_intrinsic"
 external function_call_conv : llvalue -> int = "llvm_function_call_conv"
 external set_function_call_conv : int -> llvalue -> unit
                                 = "llvm_set_function_call_conv"
+external collector : llvalue -> string option = "llvm_collector"
+external set_collector : string option -> llvalue -> unit = "llvm_set_collector"
 
 (* TODO: param attrs *)
 

bindings/ocaml/llvm/llvm.mli

@@ -754,6 +754,15 @@ external function_call_conv : llvalue -> int = "llvm_function_call_conv"
 external set_function_call_conv : int -> llvalue -> unit
                                 = "llvm_set_function_call_conv"
 
+(** [collector f] returns [Some name] if the function [f] has a garbage
+    collection algorithm specified and [None] otherwise.
+    See the method [llvm::Function::getCollector]. **)
+external collector : llvalue -> string option = "llvm_collector"
+
+(** [set_collector gc f] sets the collection algorithm for the function [f] to
+    [gc]. See the method [llvm::Function::setCollector]. **)
+external set_collector : string option -> llvalue -> unit = "llvm_set_collector"
+
 (*--... Operations on basic blocks .........................................--*)
 
 (** [basic_blocks fn] returns the basic blocks of the function [f].

bindings/ocaml/llvm/llvm_ocaml.c

@@ -536,6 +536,29 @@ CAMLprim value llvm_set_function_call_conv(value Id, LLVMValueRef Fn) {
   return Val_unit;
 }
 
+/* llvalue -> string option */
+CAMLprim value llvm_collector(LLVMValueRef Fn) {
+  const char *Collector;
+  CAMLparam0();
+  CAMLlocal2(Name, Option);
+  
+  if ((Collector = LLVMGetCollector(Fn))) {
+    Name = copy_string(Collector);
+    
+    Option = alloc(1, 0);
+    Field(Option, 0) = Name;
+    CAMLreturn(Option);
+  } else {
+    CAMLreturn(Val_int(0));
+  }
+}
+
+/* string option -> llvalue -> unit */
+CAMLprim value llvm_set_collector(value GC, LLVMValueRef Fn) {
+  LLVMSetCollector(Fn, GC == Val_int(0)? 0 : String_val(Field(GC, 0)));
+  return Val_unit;
+}
+
 /*--... Operations on basic blocks .........................................--*/
 
 /* llvalue -> llbasicblock array */

docs/LangRef.html

@@ -26,6 +26,7 @@
       <li><a href="#functionstructure">Functions</a></li>
       <li><a href="#aliasstructure">Aliases</a>
       <li><a href="#paramattrs">Parameter Attributes</a></li>
+      <li><a href="#gc">Garbage Collector Names</a></li>
       <li><a href="#moduleasm">Module-Level Inline Assembly</a></li>
       <li><a href="#datalayout">Data Layout</a></li>
     </ol>
@@ -702,15 +703,16 @@ an optional <a href="#linkage">linkage type</a>, an optional
 <a href="#paramattrs">parameter attribute</a> for the return type, a function 
 name, a (possibly empty) argument list (each with optional 
 <a href="#paramattrs">parameter attributes</a>), an optional section, an
-optional alignment, an opening curly brace, a list of basic blocks, and a
-closing curly brace.  
+optional alignment, an optional <a href="gc">garbage collector name</a>, an
+opening curly brace, a list of basic blocks, and a closing curly brace.
 
 LLVM function declarations consist of the "<tt>declare</tt>" keyword, an
 optional <a href="#linkage">linkage type</a>, an optional
 <a href="#visibility">visibility style</a>, an optional 
 <a href="#callingconv">calling convention</a>, a return type, an optional
 <a href="#paramattrs">parameter attribute</a> for the return type, a function 
-name, a possibly empty list of arguments, and an optional alignment.</p>
+name, a possibly empty list of arguments, an optional alignment, and an optional
+<a href="gc">garbage collector name</a>.</p>
 
 <p>A function definition contains a list of basic blocks, forming the CFG for
 the function.  Each basic block may optionally start with a label (giving the
@@ -824,6 +826,23 @@ declare i32 @atoi(i8*) nounwind readonly
 
 </div>
 
+<!-- ======================================================================= -->
+<div class="doc_subsection">
+  <a name="gc">Garbage Collector Names</a>
+</div>
+
+<div class="doc_text">
+<p>Each function may specify a garbage collector name, which is simply a
+string.</p>
+
+<div class="doc_code"><pre
+>define void @f() gc "name" { ...</pre></div>
+
+<p>The compiler declares the supported values of <i>name</i>. Specifying a
+collector which will cause the compiler to alter its output in order to support
+the named garbage collection algorithm.</p>
+</div>
+
 <!-- ======================================================================= -->
 <div class="doc_subsection">
   <a name="moduleasm">Module-Level Inline Assembly</a>

include/llvm-c/Core.h

@@ -339,6 +339,8 @@ LLVMValueRef LLVMGetParam(LLVMValueRef Fn, unsigned Index);
 unsigned LLVMGetIntrinsicID(LLVMValueRef Fn);
 unsigned LLVMGetFunctionCallConv(LLVMValueRef Fn);
 void LLVMSetFunctionCallConv(LLVMValueRef Fn, unsigned CC);
+const char *LLVMGetCollector(LLVMValueRef Fn);
+void LLVMSetCollector(LLVMValueRef Fn, const char *Coll);
 
 /* Operations on basic blocks */
 LLVMValueRef LLVMBasicBlockAsValue(LLVMBasicBlockRef Bb);

include/llvm/Bitcode/LLVMBitCodes.h

@@ -58,7 +58,9 @@ namespace bitc {
     MODULE_CODE_ALIAS       = 9,
     
     /// MODULE_CODE_PURGEVALS: [numvals]
-    MODULE_CODE_PURGEVALS   = 10
+    MODULE_CODE_PURGEVALS   = 10,
+    
+    MODULE_CODE_COLLECTORNAME = 11   // COLLECTORNAME: [strchr x N]
   };
   
   /// PARAMATTR blocks have code for defining a parameter attribute set.

include/llvm/Function.h

@@ -153,6 +153,13 @@ public:
   /// @brief Set the parameter attributes.
   void setParamAttrs(const ParamAttrsList *attrs);
 
+  /// hasCollector/getCollector/setCollector/clearCollector - The name of the
+  /// garbage collection algorithm to use during code generation.
+  bool hasCollector() const;
+  const char *getCollector() const;
+  void setCollector(const char *Str);
+  void clearCollector();
+
   /// @brief Determine whether the function has the given attribute.
   bool paramHasAttr(uint16_t i, ParameterAttributes attr) const {
     return ParamAttrs && ParamAttrs->paramHasAttr(i, attr);

lib/AsmParser/LLLexer.cpp

@@ -468,6 +468,7 @@ int LLLexer::LexIdentifier() {
   KEYWORD("module", MODULE);
   KEYWORD("asm", ASM_TOK);
   KEYWORD("sideeffect", SIDEEFFECT);
+  KEYWORD("gc", GC);
   
   KEYWORD("cc", CC_TOK);
   KEYWORD("ccc", CCC_TOK);

lib/AsmParser/llvmAsmParser.h.cvs

@@ -181,9 +181,10 @@
      NEST = 397,
      READNONE = 398,
      READONLY = 399,
-     DEFAULT = 400,
-     HIDDEN = 401,
-     PROTECTED = 402
+     GC = 400,
+     DEFAULT = 401,
+     HIDDEN = 402,
+     PROTECTED = 403
    };
 #endif
 /* Tokens.  */
@@ -329,16 +330,17 @@
 #define NEST 397
 #define READNONE 398
 #define READONLY 399
-#define DEFAULT 400
-#define HIDDEN 401
-#define PROTECTED 402
+#define GC 400
+#define DEFAULT 401
+#define HIDDEN 402
+#define PROTECTED 403
 
 
 
 
 #if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
 typedef union YYSTYPE
-#line 945 "/home/asl/proj/llvm/src/lib/AsmParser/llvmAsmParser.y"
+#line 945 "/Users/malichus/Source/llvm/src/llvm/lib/AsmParser/llvmAsmParser.y"
 {
   llvm::Module                           *ModuleVal;
   llvm::Function                         *FunctionVal;
@@ -385,8 +387,8 @@ typedef union YYSTYPE
   llvm::ICmpInst::Predicate         IPredicate;
   llvm::FCmpInst::Predicate         FPredicate;
 }
-/* Line 1489 of yacc.c.  */
-#line 390 "llvmAsmParser.tab.h"
+/* Line 1529 of yacc.c.  */
+#line 392 "llvmAsmParser.tab.h"
 	YYSTYPE;
 # define yystype YYSTYPE /* obsolescent; will be withdrawn */
 # define YYSTYPE_IS_DECLARED 1

lib/AsmParser/llvmAsmParser.y

@@ -1046,7 +1046,7 @@ Module *llvm::RunVMAsmParser(llvm::MemoryBuffer *MB) {
 %token<StrVal> STRINGCONSTANT ATSTRINGCONSTANT PCTSTRINGCONSTANT
 %type <StrVal> LocalName OptLocalName OptLocalAssign
 %type <StrVal> GlobalName OptGlobalAssign GlobalAssign
-%type <StrVal> OptSection SectionString
+%type <StrVal> OptSection SectionString OptGC
 
 %type <UIntVal> OptAlign OptCAlign
 
@@ -1090,7 +1090,7 @@ Module *llvm::RunVMAsmParser(llvm::MemoryBuffer *MB) {
 
 // Function Attributes
 %token SIGNEXT ZEROEXT NORETURN INREG SRET NOUNWIND NOALIAS BYVAL NEST
-%token READNONE READONLY
+%token READNONE READONLY GC
 
 // Visibility Styles
 %token DEFAULT HIDDEN PROTECTED
@@ -1244,6 +1244,12 @@ OptFuncAttrs  : /* empty */ { $$ = ParamAttr::None; }
               }
               ;
 
+OptGC         : /* empty */ { $$ = 0; }
+              | GC STRINGCONSTANT {
+                $$ = $2;
+              }
+              ;
+
 // OptAlign/OptCAlign - An optional alignment, and an optional alignment with
 // a comma before it.
 OptAlign : /*empty*/        { $$ = 0; } |
@@ -2225,7 +2231,7 @@ ArgList : ArgListH {
   };
 
 FunctionHeaderH : OptCallingConv ResultTypes GlobalName '(' ArgList ')' 
-                  OptFuncAttrs OptSection OptAlign {
+                  OptFuncAttrs OptSection OptAlign OptGC {
   std::string FunctionName(*$3);
   delete $3;  // Free strdup'd memory!
   
@@ -2328,6 +2334,10 @@ FunctionHeaderH : OptCallingConv ResultTypes GlobalName '(' ArgList ')'
     Fn->setSection(*$8);
     delete $8;
   }
+  if ($10) {
+    Fn->setCollector($10->c_str());
+    delete $10;
+  }
 
   // Add all of the arguments we parsed to the function...
   if ($5) {                     // Is null if empty...

lib/AsmParser/llvmAsmParser.y.cvs

@@ -1046,7 +1046,7 @@ Module *llvm::RunVMAsmParser(llvm::MemoryBuffer *MB) {
 %token<StrVal> STRINGCONSTANT ATSTRINGCONSTANT PCTSTRINGCONSTANT
 %type <StrVal> LocalName OptLocalName OptLocalAssign
 %type <StrVal> GlobalName OptGlobalAssign GlobalAssign
-%type <StrVal> OptSection SectionString
+%type <StrVal> OptSection SectionString OptGC
 
 %type <UIntVal> OptAlign OptCAlign
 
@@ -1090,7 +1090,7 @@ Module *llvm::RunVMAsmParser(llvm::MemoryBuffer *MB) {
 
 // Function Attributes
 %token SIGNEXT ZEROEXT NORETURN INREG SRET NOUNWIND NOALIAS BYVAL NEST
-%token READNONE READONLY
+%token READNONE READONLY GC
 
 // Visibility Styles
 %token DEFAULT HIDDEN PROTECTED
@@ -1244,6 +1244,12 @@ OptFuncAttrs  : /* empty */ { $$ = ParamAttr::None; }
               }
               ;
 
+OptGC         : /* empty */ { $$ = 0; }
+              | GC STRINGCONSTANT {
+                $$ = $2;
+              }
+              ;
+
 // OptAlign/OptCAlign - An optional alignment, and an optional alignment with
 // a comma before it.
 OptAlign : /*empty*/        { $$ = 0; } |
@@ -2225,7 +2231,7 @@ ArgList : ArgListH {
   };
 
 FunctionHeaderH : OptCallingConv ResultTypes GlobalName '(' ArgList ')' 
-                  OptFuncAttrs OptSection OptAlign {
+                  OptFuncAttrs OptSection OptAlign OptGC {
   std::string FunctionName(*$3);
   delete $3;  // Free strdup'd memory!
   
@@ -2328,6 +2334,10 @@ FunctionHeaderH : OptCallingConv ResultTypes GlobalName '(' ArgList ')'
     Fn->setSection(*$8);
     delete $8;
   }
+  if ($10) {
+    Fn->setCollector($10->c_str());
+    delete $10;
+  }
 
   // Add all of the arguments we parsed to the function...
   if ($5) {                     // Is null if empty...

lib/Bitcode/Reader/BitcodeReader.cpp

@@ -849,6 +849,7 @@ bool BitcodeReader::ParseModule(const std::string &ModuleID) {
   
   SmallVector<uint64_t, 64> Record;
   std::vector<std::string> SectionTable;
+  std::vector<std::string> CollectorTable;
 
   // Read all the records for this module.
   while (!Stream.AtEndOfStream()) {
@@ -974,6 +975,13 @@ bool BitcodeReader::ParseModule(const std::string &ModuleID) {
       SectionTable.push_back(S);
       break;
     }
+    case bitc::MODULE_CODE_COLLECTORNAME: {  // SECTIONNAME: [strchr x N]
+      std::string S;
+      if (ConvertToString(Record, 0, S))
+        return Error("Invalid MODULE_CODE_COLLECTORNAME record");
+      CollectorTable.push_back(S);
+      break;
+    }
     // GLOBALVAR: [type, isconst, initid, 
     //             linkage, alignment, section, visibility, threadlocal]
     case bitc::MODULE_CODE_GLOBALVAR: {
@@ -1016,7 +1024,7 @@ bool BitcodeReader::ParseModule(const std::string &ModuleID) {
       break;
     }
     // FUNCTION:  [type, callingconv, isproto, linkage, paramattr,
-    //             alignment, section, visibility]
+    //             alignment, section, visibility, collector]
     case bitc::MODULE_CODE_FUNCTION: {
       if (Record.size() < 8)
         return Error("Invalid MODULE_CODE_FUNCTION record");
@@ -1044,6 +1052,11 @@ bool BitcodeReader::ParseModule(const std::string &ModuleID) {
         Func->setSection(SectionTable[Record[6]-1]);
       }
       Func->setVisibility(GetDecodedVisibility(Record[7]));
+      if (Record.size() > 8 && Record[8]) {
+        if (Record[8]-1 > CollectorTable.size())
+          return Error("Invalid collector ID");
+        Func->setCollector(CollectorTable[Record[8]-1].c_str());
+      }
       
       ValueList.push_back(Func);
       

lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -297,9 +297,10 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
     WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
                       0/*TODO*/, Stream);
 
-  // Emit information about sections, computing how many there are.  Also
-  // compute the maximum alignment value.
+  // Emit information about sections and collectors, computing how many there
+  // are.  Also compute the maximum alignment value.
   std::map<std::string, unsigned> SectionMap;
+  std::map<std::string, unsigned> CollectorMap;
   unsigned MaxAlignment = 0;
   unsigned MaxGlobalType = 0;
   for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
@@ -317,13 +318,24 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   }
   for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
     MaxAlignment = std::max(MaxAlignment, F->getAlignment());
-    if (!F->hasSection()) continue;
-    // Give section names unique ID's.
-    unsigned &Entry = SectionMap[F->getSection()];
-    if (Entry != 0) continue;
-    WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
-                      0/*TODO*/, Stream);
-    Entry = SectionMap.size();
+    if (F->hasSection()) {
+      // Give section names unique ID's.
+      unsigned &Entry = SectionMap[F->getSection()];
+      if (!Entry) {
+        WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
+                          0/*TODO*/, Stream);
+        Entry = SectionMap.size();
+      }
+    }
+    if (F->hasCollector()) {
+      // Same for collector names.
+      unsigned &Entry = CollectorMap[F->getCollector()];
+      if (!Entry) {
+        WriteStringRecord(bitc::MODULE_CODE_COLLECTORNAME, F->getCollector(),
+                          0/*TODO*/, Stream);
+        Entry = CollectorMap.size();
+      }
+    }
   }
   
   // Emit abbrev for globals, now that we know # sections and max alignment.
@@ -383,7 +395,7 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
   // Emit the function proto information.
   for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
     // FUNCTION:  [type, callingconv, isproto, paramattr,
-    //             linkage, alignment, section, visibility]
+    //             linkage, alignment, section, visibility, collector]
     Vals.push_back(VE.getTypeID(F->getType()));
     Vals.push_back(F->getCallingConv());
     Vals.push_back(F->isDeclaration());
@@ -392,6 +404,7 @@ static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
     Vals.push_back(Log2_32(F->getAlignment())+1);
     Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0);
     Vals.push_back(getEncodedVisibility(F));
+    Vals.push_back(F->hasCollector() ? CollectorMap[F->getCollector()] : 0);
     
     unsigned AbbrevToUse = 0;
     Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);

lib/Transforms/Utils/CloneModule.cpp

@@ -67,6 +67,8 @@ Module *llvm::CloneModule(const Module *M,
                    GlobalValue::ExternalLinkage, I->getName(), New);
     NF->setCallingConv(I->getCallingConv());
     NF->setParamAttrs(I->getParamAttrs());
+    if (I->hasCollector())
+      NF->setCollector(I->getCollector());
     ValueMap[I]= NF;
   }
 

lib/VMCore/AsmWriter.cpp

@@ -1112,6 +1112,8 @@ void AssemblyWriter::printFunction(const Function *F) {
     Out << " section \"" << F->getSection() << '"';
   if (F->getAlignment())
     Out << " align " << F->getAlignment();
+  if (F->hasCollector())
+    Out << " gc \"" << F->getCollector() << '"';
 
   if (F->isDeclaration()) {
     Out << "\n";

lib/VMCore/Core.cpp

@@ -619,6 +619,19 @@ void LLVMSetFunctionCallConv(LLVMValueRef Fn, unsigned CC) {
   return unwrap<Function>(Fn)->setCallingConv(CC);
 }
 
+const char *LLVMGetCollector(LLVMValueRef Fn) {
+  Function *F = unwrap<Function>(Fn);
+  return F->hasCollector()? F->getCollector() : 0;
+}
+
+void LLVMSetCollector(LLVMValueRef Fn, const char *Coll) {
+  Function *F = unwrap<Function>(Fn);
+  if (Coll)
+    F->setCollector(Coll);
+  else
+    F->clearCollector();
+}
+
 /*--.. Operations on basic blocks ..........................................--*/
 
 LLVMValueRef LLVMBasicBlockAsValue(LLVMBasicBlockRef Bb) {

lib/VMCore/Function.cpp

@@ -17,8 +17,10 @@
 #include "llvm/CodeGen/ValueTypes.h"
 #include "llvm/Support/LeakDetector.h"
 #include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/StringPool.h"
 #include "SymbolTableListTraitsImpl.h"
 #include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/StringExtras.h"
 using namespace llvm;
 
@@ -297,6 +299,9 @@ Function::~Function() {
   // Drop our reference to the parameter attributes, if any.
   if (ParamAttrs)
     ParamAttrs->dropRef();
+  
+  // Remove the function from the on-the-side collector table.
+  clearCollector();
 }
 
 void Function::BuildLazyArguments() const {
@@ -379,6 +384,40 @@ void Function::dropAllReferences() {
   BasicBlocks.clear();    // Delete all basic blocks...
 }
 
+// Maintain the collector name for each function in an on-the-side table. This
+// saves allocating an additional word in Function for programs which do not use
+// GC (i.e., most programs) at the cost of increased overhead for clients which
+// do use GC.
+static DenseMap<const Function*,PooledStringPtr> *CollectorNames;
+static StringPool *CollectorNamePool;
+
+bool Function::hasCollector() const {
+  return CollectorNames && CollectorNames->count(this);
+}
+
+const char *Function::getCollector() const {
+  assert(hasCollector() && "Function has no collector");
+  return *(*CollectorNames)[this];
+}
+
+void Function::setCollector(const char *Str) {
+  if (!CollectorNamePool)
+    CollectorNamePool = new StringPool();
+  if (!CollectorNames)
+    CollectorNames = new DenseMap<const Function*,PooledStringPtr>();
+  (*CollectorNames)[this] = CollectorNamePool->intern(Str);
+}
+
+void Function::clearCollector() {
+  if (CollectorNames) {
+    CollectorNames->erase(this);
+    if (CollectorNames->empty()) {
+      delete CollectorNames;
+      CollectorNames = 0;
+    }
+  }
+}
+
 /// getIntrinsicID - This method returns the ID number of the specified
 /// function, or Intrinsic::not_intrinsic if the function is not an
 /// intrinsic, or if the pointer is null.  This value is always defined to be

test/Assembler/2007-09-29-GC.ll

@@ -0,0 +1,12 @@
+; RUN: llvm-as < %s | llvm-dis | grep {@f.*gc.*shadowstack}
+; RUN: llvm-as < %s | llvm-dis | grep {@g.*gc.*java}
+
+define void @f() gc "shadowstack" {
+entry:
+	ret void
+}
+
+define void @g() gc "java" {
+entry:
+	ret void
+}

test/Bindings/Ocaml/vmcore.ml

@@ -25,7 +25,8 @@ let insist cond =
     exit_status := 10;
     "    FAIL "
   end in
-  prerr_endline (msg ^ (string_of_int !case_num))
+  prerr_endline ("    " ^ (string_of_int !case_num) ^ if cond then ""
+                                                              else " FAIL")
 
 let suite name f =
   prerr_endline (name ^ ":");
@@ -490,7 +491,20 @@ let test_functions () =
   insist (ccc = function_call_conv fn);
   set_function_call_conv fastcc fn;
   insist (fastcc = function_call_conv fn);
-  ignore (build_unreachable (builder_at_end (entry_block fn)))
+  ignore (build_unreachable (builder_at_end (entry_block fn)));
+  
+  begin group "collector";
+    (* RUN: grep {Fn6.*gc.*shadowstack} < %t.ll
+     *)
+    let fn = define_function "Fn6" ty m in
+    insist (None = collector fn);
+    set_collector (Some "ocaml") fn;
+    insist (Some "ocaml" = collector fn);
+    set_collector None fn;
+    insist (None = collector fn);
+    set_collector (Some "shadowstack") fn;
+    ignore (build_unreachable (builder_at_end (entry_block fn)));
+  end
 
 
 (*===-- Basic Blocks ------------------------------------------------------===*)
@@ -749,7 +763,6 @@ let test_builder () =
     let t3 = const_vector [| one; one; zero; zero |] in
     let vec1 = build_insertelement t1 p1 p2 "Vec1" atentry in
     let vec2 = build_insertelement t2 p1 p2 "Vec2" atentry in
-    let vec3 = build_insertelement t3 p1 p2 "Vec3" atentry in
     
     ignore (build_extractelement vec1 p2 "Inst49" atentry);
     ignore (build_insertelement vec1 p1 p2 "Inst50" atentry);

test/CodeGen/Generic/GC/alloc_loop.ll

@@ -7,7 +7,7 @@ declare void @llvm_gc_initialize(i32)
 declare void @llvm.gcroot(i8**, i8*)
 declare void @llvm.gcwrite(i8*, i8*, i8**)
 
-define i32 @main() {
+define i32 @main() gc "shadow-stack" {
 entry:
 	%A = alloca i8*
 	%B = alloca i8**