[MemorySanitizer] NFC. Do not use GET_INTRINSIC_MODREF_BEHAVIOR table.

[igor-laevsky]

Summary

NFC. It is now possible to infer intrinsic modref behaviour purely from intrinsic attributes. This change will allow to completely remove GET_INTRINSIC_MODREF_BEHAVIOR table.

[eugenis]

Looks great, thanks!

lib/Transforms/Instrumentation/MemorySanitizer.cpp

#endif
   void visitVAStartInst(VAStartInst &I) {
     VAHelper->visitVAStartInst(I);
   }
 
   void visitVACopyInst(VACopyInst &I) {
     VAHelper->visitVACopyInst(I);
   }
 
-  enum IntrinsicKind {
-    IK_DoesNotAccessMemory,
-    IK_OnlyReadsMemory,
-    IK_WritesMemory
-  };
-
-  static IntrinsicKind getIntrinsicKind(Intrinsic::ID iid) {
-    const int FMRB_DoesNotAccessMemory = IK_DoesNotAccessMemory;
-    const int FMRB_OnlyReadsArgumentPointees = IK_OnlyReadsMemory;
-    const int FMRB_OnlyReadsMemory = IK_OnlyReadsMemory;
-    const int FMRB_OnlyAccessesArgumentPointees = IK_WritesMemory;
-    const int FMRB_UnknownModRefBehavior = IK_WritesMemory;
-#define GET_INTRINSIC_MODREF_BEHAVIOR
-#define FunctionModRefBehavior IntrinsicKind
-#include "llvm/IR/Intrinsics.gen"
-#undef FunctionModRefBehavior
-#undef GET_INTRINSIC_MODREF_BEHAVIOR
-  }
-
   /// \brief Handle vector store-like intrinsics.
   ///
   /// Instrument intrinsics that look like a simple SIMD store: writes memory,
   /// has 1 pointer argument and 1 vector argument, returns void.
   bool handleVectorStoreIntrinsic(IntrinsicInst &I) {
     IRBuilder<> IRB(&I);
     Value* Addr = I.getArgOperand(0);
     Value *Shadow = getShadow(&I, 1);
#endif
   ///
   /// We special-case intrinsics where this approach fails. See llvm.bswap
   /// handling as an example of that.
   bool handleUnknownIntrinsic(IntrinsicInst &I) {
     unsigned NumArgOperands = I.getNumArgOperands();
     if (NumArgOperands == 0)
       return false;
 
-    Intrinsic::ID iid = I.getIntrinsicID();
-    IntrinsicKind IK = getIntrinsicKind(iid);
-    bool OnlyReadsMemory = IK == IK_OnlyReadsMemory;
-    bool WritesMemory = IK == IK_WritesMemory;
-    assert(!(OnlyReadsMemory && WritesMemory));
-
     if (NumArgOperands == 2 &&
         I.getArgOperand(0)->getType()->isPointerTy() &&
         I.getArgOperand(1)->getType()->isVectorTy() &&
         I.getType()->isVoidTy() &&
-        WritesMemory) {
+        !I.onlyReadsMemory()) {
       // This looks like a vector store.
       return handleVectorStoreIntrinsic(I);
     }
 
     if (NumArgOperands == 1 &&
         I.getArgOperand(0)->getType()->isPointerTy() &&
         I.getType()->isVectorTy() &&
-        OnlyReadsMemory) {
+        I.onlyReadsMemory()) {
       // This looks like a vector load.
       return handleVectorLoadIntrinsic(I);
     }
 
-    if (!OnlyReadsMemory && !WritesMemory)
+    if (I.doesNotAccessMemory())
       if (maybeHandleSimpleNomemIntrinsic(I))
         return true;
 
     // FIXME: detect and handle SSE maskstore/maskload
     return false;
   }
 
   void handleBswap(IntrinsicInst &I) {