[PATCH] D77616: [AddressSanitizer] Refactor ClDebug{Min, Max} handling

[Jann Horn via Phabricator via llvm-commits]

thejh created this revision.
thejh added a project: LLVM.
Herald added subscribers: llvm-commits, hiraditya.

A following commit will split the loop over ToInstrument into two.
To avoid having to duplicate the condition for suppressing instrumentation
sites based on ClDebug{Min,Max}, refactor it out into a new function.

While we're at it, we can also avoid the indirection through
NumInstrumented for setting FunctionModified.

This is patch 1/4 of a patch series.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D77616

Files:
  llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp


Index: llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
===================================================================
--- llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -639,6 +639,7 @@
                                  Value *SizeArgument, uint32_t Exp);
   void instrumentMemIntrinsic(MemIntrinsic *MI);
   Value *memToShadow(Value *Shadow, IRBuilder<> &IRB);
+  bool suppressInstrumentationSiteForDebug(int &instrumented);
   bool instrumentFunction(Function &F, const TargetLibraryInfo *TLI);
   bool maybeInsertAsanInitAtFunctionEntry(Function &F);
   void maybeInsertDynamicShadowAtFunctionEntry(Function &F);
@@ -2611,6 +2612,13 @@
   }
 }
 
+bool AddressSanitizer::suppressInstrumentationSiteForDebug(int &instrumented) {
+  bool ShouldInstrument = ClDebugMin < 0 || ClDebugMax < 0 ||
+          (instrumented >= ClDebugMin && instrumented <= ClDebugMax);
+  instrumented++;
+  return !ShouldInstrument;
+}
+
 bool AddressSanitizer::instrumentFunction(Function &F,
                                           const TargetLibraryInfo *TLI) {
   if (F.getLinkage() == GlobalValue::AvailableExternallyLinkage) return false;
@@ -2712,15 +2720,14 @@
   // Instrument.
   int NumInstrumented = 0;
   for (auto Inst : ToInstrument) {
-    if (ClDebugMin < 0 || ClDebugMax < 0 ||
-        (NumInstrumented >= ClDebugMin && NumInstrumented <= ClDebugMax)) {
+    if (!suppressInstrumentationSiteForDebug(NumInstrumented)) {
       if (isInterestingMemoryAccess(Inst, &IsWrite, &TypeSize, &Alignment))
         instrumentMop(ObjSizeVis, Inst, UseCalls,
                       F.getParent()->getDataLayout());
       else
         instrumentMemIntrinsic(cast<MemIntrinsic>(Inst));
     }
-    NumInstrumented++;
+    FunctionModified = true;
   }
 
   FunctionStackPoisoner FSP(F, *this);
@@ -2735,10 +2742,10 @@
 
   for (auto Inst : PointerComparisonsOrSubtracts) {
     instrumentPointerComparisonOrSubtraction(Inst);
-    NumInstrumented++;
+    FunctionModified = true;
   }
 
-  if (NumInstrumented > 0 || ChangedStack || !NoReturnCalls.empty())
+  if (ChangedStack || !NoReturnCalls.empty())
     FunctionModified = true;
 
   LLVM_DEBUG(dbgs() << "ASAN done instrumenting: " << FunctionModified << " "


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