[llvm] r236779 - MSan: Use `createSanitizerCtor` to create ctor, and call `__msan_init`

[Ismail Pazarbasi]

Author: ismailp
Date: Thu May  7 16:41:52 2015
New Revision: 236779

URL: http://llvm.org/viewvc/llvm-project?rev=236779&view=rev
Log:
MSan: Use `createSanitizerCtor` to create ctor, and call `__msan_init`

Reviewers: kcc, eugenis

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D8781

Modified:
    llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
    llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll

Modified: llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp?rev=236779&r1=236778&r2=236779&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp Thu May  7 16:41:52 2015
@@ -191,6 +191,9 @@ static cl::opt<bool> ClCheckConstantShad
        cl::desc("Insert checks for constant shadow values"),
        cl::Hidden, cl::init(false));
 
+static const char *const kMsanModuleCtorName = "msan.module_ctor";
+static const char *const kMsanInitName = "__msan_init";
+
 namespace {
 
 // Memory map parameters used in application-to-shadow address calculation.
@@ -332,6 +335,7 @@ class MemorySanitizer : public FunctionP
   MDNode *OriginStoreWeights;
   /// \brief An empty volatile inline asm that prevents callback merge.
   InlineAsm *EmptyAsm;
+  Function *MsanCtorFunction;
 
   friend struct MemorySanitizerVisitor;
   friend struct VarArgAMD64Helper;
@@ -491,9 +495,12 @@ bool MemorySanitizer::doInitialization(M
   ColdCallWeights = MDBuilder(*C).createBranchWeights(1, 1000);
   OriginStoreWeights = MDBuilder(*C).createBranchWeights(1, 1000);
 
-  // Insert a call to __msan_init/__msan_track_origins into the module's CTORs.
-  appendToGlobalCtors(M, cast<Function>(M.getOrInsertFunction(
-                      "__msan_init", IRB.getVoidTy(), nullptr)), 0);
+  std::tie(MsanCtorFunction, std::ignore) =
+      createSanitizerCtorAndInitFunctions(M, kMsanModuleCtorName, kMsanInitName,
+                                          /*InitArgTypes=*/{},
+                                          /*InitArgs=*/{});
+
+  appendToGlobalCtors(M, MsanCtorFunction, 0);
 
   if (TrackOrigins)
     new GlobalVariable(M, IRB.getInt32Ty(), true, GlobalValue::WeakODRLinkage,
@@ -2983,6 +2990,8 @@ VarArgHelper *CreateVarArgHelper(Functio
 }  // namespace
 
 bool MemorySanitizer::runOnFunction(Function &F) {
+  if (&F == MsanCtorFunction)
+    return false;
   MemorySanitizerVisitor Visitor(F, *this);
 
   // Clear out readonly/readnone attributes.

Modified: llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll?rev=236779&r1=236778&r2=236779&view=diff
==============================================================================
--- llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll (original)
+++ llvm/trunk/test/Instrumentation/MemorySanitizer/msan_basic.ll Thu May  7 16:41:52 2015
@@ -4,8 +4,7 @@
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
 
-; Check the presence of __msan_init
-; CHECK: @llvm.global_ctors {{.*}} @__msan_init
+; CHECK: @llvm.global_ctors {{.*}} @msan.module_ctor
 
 ; Check the presence and the linkage type of __msan_track_origins and
 ; other interface symbols.
@@ -878,3 +877,6 @@ define void @MismatchedReturnTypeTailCal
 ; CHECK-LABEL: define void @MismatchedReturnTypeTailCall
 ; CHECK: tail call i32 @InnerTailCall
 ; CHECK: ret void
+
+; CHECK: define internal void @msan.module_ctor
+; CHECK: call void @__msan_init()