[llvm] ade190c - [Attributor] AACallEdges, Add a way to ask nonasm unknown callees

[Kuter Dinel via llvm-commits]

Author: Kuter Dinel
Date: 2021-07-15T06:10:42+03:00
New Revision: ade190c5eabfb432fa273b354d371f84a312052b

URL: https://github.com/llvm/llvm-project/commit/ade190c5eabfb432fa273b354d371f84a312052b
DIFF: https://github.com/llvm/llvm-project/commit/ade190c5eabfb432fa273b354d371f84a312052b.diff

LOG: [Attributor] AACallEdges, Add a way to ask nonasm unknown callees

This patch adds a feature to AACallEdges AbstractAttribute that allows
users to ask if there is a unknown callee that isn't a inline assembly.
This feature is needed by some of it's users.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D105992

Added: 
    

Modified: 
    llvm/include/llvm/Transforms/IPO/Attributor.h
    llvm/lib/Transforms/IPO/AttributorAttributes.cpp

Removed: 
    


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diff  --git a/llvm/include/llvm/Transforms/IPO/Attributor.h b/llvm/include/llvm/Transforms/IPO/Attributor.h
index 7d10464e59a3c..fd5d252aafb35 100644
--- a/llvm/include/llvm/Transforms/IPO/Attributor.h
+++ b/llvm/include/llvm/Transforms/IPO/Attributor.h
@@ -4186,9 +4186,12 @@ struct AACallEdges : public StateWrapper<BooleanState, AbstractAttribute>,
   /// Get the optimistic edges.
   virtual const SetVector<Function *> &getOptimisticEdges() const = 0;
 
-  /// Is there in this function call with a unknown Callee.
+  /// Is there any call with a unknown callee.
   virtual bool hasUnknownCallee() const = 0;
 
+  /// Is there any call with a unknown callee, excluding any inline asm.
+  virtual bool hasNonAsmUnknownCallee() const = 0;
+
   /// Iterator for exploring the call graph.
   AACallEdgeIterator optimisticEdgesBegin() const override {
     return AACallEdgeIterator(A, getOptimisticEdges().begin());

diff  --git a/llvm/lib/Transforms/IPO/AttributorAttributes.cpp b/llvm/lib/Transforms/IPO/AttributorAttributes.cpp
index 77d11e964b450..83cd1ee4de66b 100644
--- a/llvm/lib/Transforms/IPO/AttributorAttributes.cpp
+++ b/llvm/lib/Transforms/IPO/AttributorAttributes.cpp
@@ -8443,6 +8443,7 @@ struct AACallEdgesFunction : public AACallEdges {
   ChangeStatus updateImpl(Attributor &A) override {
     ChangeStatus Change = ChangeStatus::UNCHANGED;
     bool OldHasUnknownCallee = HasUnknownCallee;
+    bool OldHasUnknownCalleeNonAsm = HasUnknownCalleeNonAsm;
 
     auto AddCalledFunction = [&](Function *Fn) {
       if (CalledFunctions.insert(Fn)) {
@@ -8459,6 +8460,7 @@ struct AACallEdgesFunction : public AACallEdges {
       } else {
         LLVM_DEBUG(dbgs() << "[AACallEdges] Unrecognized value: " << V << "\n");
         HasUnknown = true;
+        HasUnknownCalleeNonAsm = true;
       }
 
       // Explore all values.
@@ -8467,16 +8469,22 @@ struct AACallEdgesFunction : public AACallEdges {
 
     // Process any value that we might call.
     auto ProcessCalledOperand = [&](Value *V, Instruction *Ctx) {
-      if (!genericValueTraversal<bool>(A, IRPosition::value(*V), *this,
-                                       HasUnknownCallee, VisitValue, nullptr,
-                                       false))
+      if (!genericValueTraversal<bool>(
+              A, IRPosition::value(*V), *this, HasUnknownCallee, VisitValue,
+              nullptr, false)) {
         // If we haven't gone through all values, assume that there are unknown
         // callees.
         HasUnknownCallee = true;
+        HasUnknownCalleeNonAsm = true;
+      }
     };
 
     auto ProcessCallInst = [&](Instruction &Inst) {
       CallBase &CB = static_cast<CallBase &>(Inst);
+      if (CB.isInlineAsm()) {
+        HasUnknownCallee = true;
+        return true;
+      }
 
       // Process callee metadata if available.
       if (auto *MD = Inst.getMetadata(LLVMContext::MD_callees)) {
@@ -8505,12 +8513,16 @@ struct AACallEdgesFunction : public AACallEdges {
     // Visit all callable instructions.
     bool UsedAssumedInformation = false;
     if (!A.checkForAllCallLikeInstructions(ProcessCallInst, *this,
-                                           UsedAssumedInformation))
+                                           UsedAssumedInformation)) {
       // If we haven't looked at all call like instructions, assume that there
       // are unknown callees.
       HasUnknownCallee = true;
+      HasUnknownCalleeNonAsm = true;
+    }
+
     // Track changes.
-    if (OldHasUnknownCallee != HasUnknownCallee)
+    if (OldHasUnknownCallee != HasUnknownCallee ||
+        OldHasUnknownCalleeNonAsm != HasUnknownCalleeNonAsm)
       Change = ChangeStatus::CHANGED;
 
     return Change;
@@ -8522,6 +8534,10 @@ struct AACallEdgesFunction : public AACallEdges {
 
   virtual bool hasUnknownCallee() const override { return HasUnknownCallee; }
 
+  virtual bool hasNonAsmUnknownCallee() const override {
+    return HasUnknownCalleeNonAsm;
+  }
+
   const std::string getAsStr() const override {
     return "CallEdges[" + std::to_string(HasUnknownCallee) + "," +
            std::to_string(CalledFunctions.size()) + "]";
@@ -8532,8 +8548,11 @@ struct AACallEdgesFunction : public AACallEdges {
   /// Optimistic set of functions that might be called by this function.
   SetVector<Function *> CalledFunctions;
 
-  /// Does this function have a call to a function that we don't know about.
+  /// Is there any call with a unknown callee.
   bool HasUnknownCallee = false;
+
+  /// Is there any call with a unknown callee, excluding any inline asm.
+  bool HasUnknownCalleeNonAsm = false;
 };
 
 struct AAFunctionReachabilityFunction : public AAFunctionReachability {