From 2e6cd338c6d4605fa599f583bc8ca202dda6a551 Mon Sep 17 00:00:00 2001
From: Jianzhou Zhao <jianzhouzh@google.com>
Date: Thu, 18 Feb 2021 08:04:30 +0000
Subject: [PATCH] [dfsan] Refactor runtime functions checking

This is a part of https://reviews.llvm.org/D95835.

Reviewed-by: morehouse

Differential Revision: https://reviews.llvm.org/D96940
---
 .../Instrumentation/DataFlowSanitizer.cpp     | 42 ++++++++++++-------
 1 file changed, 27 insertions(+), 15 deletions(-)

diff --git a/llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp
index 331715765b32..10e510baee74 100644
--- a/llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/DataFlowSanitizer.cpp
@@ -393,6 +393,7 @@ class DataFlowSanitizer {
   FunctionCallee DFSanStoreCallbackFn;
   FunctionCallee DFSanMemTransferCallbackFn;
   FunctionCallee DFSanCmpCallbackFn;
+  SmallPtrSet<Value *, 12> DFSanRuntimeFunctions;
   MDNode *ColdCallWeights;
   DFSanABIList ABIList;
   DenseMap<Value *, Function *> UnwrappedFnMap;
@@ -1048,6 +1049,30 @@ void DataFlowSanitizer::initializeRuntimeFunctions(Module &M) {
       Mod->getOrInsertFunction("__dfsan_nonzero_label", DFSanNonzeroLabelFnTy);
   DFSanVarargWrapperFn = Mod->getOrInsertFunction("__dfsan_vararg_wrapper",
                                                   DFSanVarargWrapperFnTy);
+
+  DFSanRuntimeFunctions.insert(DFSanUnionFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanCheckedUnionFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanUnionLoadFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanUnionLoadFast16LabelsFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanUnimplementedFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanSetLabelFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanNonzeroLabelFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanVarargWrapperFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanLoadCallbackFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanStoreCallbackFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanMemTransferCallbackFn.getCallee()->stripPointerCasts());
+  DFSanRuntimeFunctions.insert(
+      DFSanCmpCallbackFn.getCallee()->stripPointerCasts());
 }
 
 // Initializes event callback functions and declare them in the module
@@ -1095,22 +1120,9 @@ bool DataFlowSanitizer::runImpl(Module &M) {
 
   std::vector<Function *> FnsToInstrument;
   SmallPtrSet<Function *, 2> FnsWithNativeABI;
-  for (Function &i : M) {
-    if (!i.isIntrinsic() &&
-        &i != DFSanUnionFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanCheckedUnionFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanUnionLoadFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanUnionLoadFast16LabelsFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanUnimplementedFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanSetLabelFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanNonzeroLabelFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanVarargWrapperFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanLoadCallbackFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanStoreCallbackFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanMemTransferCallbackFn.getCallee()->stripPointerCasts() &&
-        &i != DFSanCmpCallbackFn.getCallee()->stripPointerCasts())
+  for (Function &i : M)
+    if (!i.isIntrinsic() && !DFSanRuntimeFunctions.contains(&i))
       FnsToInstrument.push_back(&i);
-  }
 
   // Give function aliases prefixes when necessary, and build wrappers where the
   // instrumentedness is inconsistent.
-- 
2.34.1