Fix quadratic behavior in InlineFunction by fetching the personality function of...

The callee is usually smaller than the caller, too. This reduces the compile
time of ARMDisassembler.cpp by 32% (Release build). It still takes ages to
compile though.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145690 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Utils/InlineFunction.cpp b/lib/Transforms/Utils/InlineFunction.cpp
index dd4a659b735ab0bbf309e181bdac796f267ddf6c..f89e1b1c537b4cb24d9724edb58739a1bb5b53ea 100644 (file)
--- a/lib/Transforms/Utils/InlineFunction.cpp
+++ b/lib/Transforms/Utils/InlineFunction.cpp
@@ -924,40 +924,44 @@ bool llvm::InlineFunction(CallSite CS, InlineFunctionInfo &IFI) {
       return false;
   }
 
-  // Find the personality function used by the landing pads of the caller. If it
-  // exists, then check to see that it matches the personality function used in
-  // the callee.
-  for (Function::const_iterator
-         I = Caller->begin(), E = Caller->end(); I != E; ++I)
+  // Get the personality function from the callee if it contains a landing pad.
+  Value *CalleePersonality = 0;
+  for (Function::const_iterator I = CalledFunc->begin(), E = CalledFunc->end();
+       I != E; ++I)
     if (const InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator())) {
       const BasicBlock *BB = II->getUnwindDest();
-      // FIXME: This 'isa' here should become go away once the new EH system is
-      // in place.
-      if (!isa<LandingPadInst>(BB->getFirstNonPHI()))
-        continue;
-      const LandingPadInst *LP = cast<LandingPadInst>(BB->getFirstNonPHI());
-      const Value *CallerPersFn = LP->getPersonalityFn();
-
-      // If the personality functions match, then we can perform the
-      // inlining. Otherwise, we can't inline.
-      // TODO: This isn't 100% true. Some personality functions are proper
-      //       supersets of others and can be used in place of the other.
-      for (Function::const_iterator
-             I = CalledFunc->begin(), E = CalledFunc->end(); I != E; ++I)
-        if (const InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator())) {
-          const BasicBlock *BB = II->getUnwindDest();
-          // FIXME: This 'if/dyn_cast' here should become a normal 'cast' once
-          // the new EH system is in place.
-          if (const LandingPadInst *LP =
-              dyn_cast<LandingPadInst>(BB->getFirstNonPHI()))
-            if (CallerPersFn != LP->getPersonalityFn())
-              return false;
-          break;
-        }
-
+      // FIXME: This 'if/dyn_cast' here should become a normal 'cast' once
+      // the new EH system is in place.
+      if (const LandingPadInst *LP =
+          dyn_cast<LandingPadInst>(BB->getFirstNonPHI()))
+        CalleePersonality = LP->getPersonalityFn();
       break;
     }
 
+  // Find the personality function used by the landing pads of the caller. If it
+  // exists, then check to see that it matches the personality function used in
+  // the callee.
+  if (CalleePersonality)
+    for (Function::const_iterator I = Caller->begin(), E = Caller->end();
+         I != E; ++I)
+      if (const InvokeInst *II = dyn_cast<InvokeInst>(I->getTerminator())) {
+        const BasicBlock *BB = II->getUnwindDest();
+        // FIXME: This 'isa' here should become go away once the new EH system
+        // is in place.
+        if (!isa<LandingPadInst>(BB->getFirstNonPHI()))
+          continue;
+        const LandingPadInst *LP = cast<LandingPadInst>(BB->getFirstNonPHI());
+
+        // If the personality functions match, then we can perform the
+        // inlining. Otherwise, we can't inline.
+        // TODO: This isn't 100% true. Some personality functions are proper
+        //       supersets of others and can be used in place of the other.
+        if (LP->getPersonalityFn() != CalleePersonality)
+          return false;
+
+        break;
+      }
+
   // Get an iterator to the last basic block in the function, which will have
   // the new function inlined after it.
   //