[BasicAA] Remove special casing of memset_pattern16 in favor of generic attribute...

[oota-llvm.git] / lib / Transforms / IPO / InferFunctionAttrs.cpp

diff --git a/lib/Transforms/IPO/InferFunctionAttrs.cpp b/lib/Transforms/IPO/InferFunctionAttrs.cpp
index 0f0182ef92be9e6270776554cd1c3325366bd837..4295a7595c29f3952c6caaa1917d30b96cf1e0e1 100644 (file)
--- a/lib/Transforms/IPO/InferFunctionAttrs.cpp
+++ b/lib/Transforms/IPO/InferFunctionAttrs.cpp
@@ -22,6 +22,7 @@ using namespace llvm;
 
 STATISTIC(NumReadNone, "Number of functions inferred as readnone");
 STATISTIC(NumReadOnly, "Number of functions inferred as readonly");
+STATISTIC(NumArgMemOnly, "Number of functions inferred as argmemonly");
 STATISTIC(NumNoUnwind, "Number of functions inferred as nounwind");
 STATISTIC(NumNoCapture, "Number of arguments inferred as nocapture");
 STATISTIC(NumReadOnlyArg, "Number of arguments inferred as readonly");
@@ -44,6 +45,15 @@ static bool setOnlyReadsMemory(Function &F) {
   return true;
 }
 
+static bool setOnlyAccessesArgMemory(Function &F) {
+  if (F.onlyAccessesArgMemory())
+    return false;
+  F.setOnlyAccessesArgMemory ();
+  ++NumArgMemOnly;
+  return true;
+}
+
+
 static bool setDoesNotThrow(Function &F) {
   if (F.doesNotThrow())
     return false;
@@ -900,6 +910,20 @@ static bool inferPrototypeAttributes(Function &F,
     Changed |= setDoesNotAlias(F, AttributeSet::ReturnIndex);
     return Changed;
 
+  //TODO: add LibFunc entries for:
+  //case LibFunc::memset_pattern4:
+  //case LibFunc::memset_pattern8:
+  case LibFunc::memset_pattern16:
+    if (FTy->isVarArg() || FTy->getNumParams() != 3 ||
+        !isa<PointerType>(FTy->getParamType(0)) ||
+        !isa<PointerType>(FTy->getParamType(1)) ||
+        !isa<IntegerType>(FTy->getParamType(2)))
+      return false;
+
+    Changed |= setOnlyAccessesArgMemory(F);
+    Changed |= setOnlyReadsMemory(F, 2);
+    return Changed;
+
   default:
     // FIXME: It'd be really nice to cover all the library functions we're
     // aware of here.