PNaCl ABI: Strip out attributes on functions and function calls

Add a pass, StripAttributes, for doing this, and enable it.

Add an ABI check to reject these attributes.

BUG=https://code.google.com/p/nativeclient/issues/detail?id=2346
BUG=https://code.google.com/p/nativeclient/issues/detail?id=3415
TEST=*.ll tests + PNaCl toolchain trybots

Review URL: https://codereview.chromium.org/16325025

2 files changed, 19 insertions, 0 deletions

diff --git a/lib/Analysis/NaCl/PNaClABIVerifyFunctions.cpp b/lib/Analysis/NaCl/PNaClABIVerifyFunctions.cpp
index 43eef2f6c0..167cad15d0 100644
--- a/lib/Analysis/NaCl/PNaClABIVerifyFunctions.cpp
+++ b/lib/Analysis/NaCl/PNaClABIVerifyFunctions.cpp
@@ -258,6 +258,8 @@ const char *PNaClABIVerifyFunctions::checkInstruction(const Instruction *Inst) {
     case Instruction::Call:
       if (cast<CallInst>(Inst)->isInlineAsm())
         return "inline assembly";
+      if (!cast<CallInst>(Inst)->getAttributes().isEmpty())
+        return "bad call attributes";
 
       // Intrinsic calls can have multiple pointer arguments and
       // metadata arguments, so handle them specially.
diff --git a/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp b/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
index 7daeabd0e8..91f71c949c 100644
--- a/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
+++ b/lib/Analysis/NaCl/PNaClABIVerifyModule.cpp
@@ -305,6 +305,18 @@ static bool isCompoundElement(const Constant *C) {
   return true;
 }
 
+static std::string getAttributesAsString(AttributeSet Attrs) {
+  std::string AttrsAsString;
+  for (unsigned Slot = 0; Slot < Attrs.getNumSlots(); ++Slot) {
+    for (AttributeSet::iterator Attr = Attrs.begin(Slot),
+           E = Attrs.end(Slot); Attr != E; ++Attr) {
+      AttrsAsString += " ";
+      AttrsAsString += Attr->getAsString();
+    }
+  }
+  return AttrsAsString;
+}
+
 // This checks that the GlobalVariable has the normal form produced by
 // the FlattenGlobals pass.
 void PNaClABIVerifyModule::checkGlobalIsFlattened(const GlobalVariable *GV) {
@@ -366,6 +378,11 @@ bool PNaClABIVerifyModule::runOnModule(Module &M) {
         Reporter->addError() << "Function " << MI->getName()
                              << " is declared but not defined (disallowed)\n";
       }
+      if (!MI->getAttributes().isEmpty()) {
+        Reporter->addError()
+            << "Function " << MI->getName() << " has disallowed attributes:"
+            << getAttributesAsString(MI->getAttributes()) << "\n";
+      }
     }
 
     checkGlobalValueCommon(MI);