Move the libcall annotating part from doFinalization to doInitialization.

Finalization occurs after all the FunctionPasses in the group have run, which
is clearly not what we want.

This also means that we have to make sure that we apply the right param 
attributes when creating a new function.

Also, add a missed optimization: strdup and strndup. NoCapture and 
NoAlias return!

llvm-svn: 61658

1 files changed, 77 insertions, 18 deletions

diff --git a/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp
index 829d1344b11..2c0008e6f1f 100644
--- a/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/Scalar/SimplifyLibCalls.cpp
@@ -123,7 +123,13 @@ Value *LibCallOptimization::CastToCStr(Value *V, IRBuilder<> &B) {
 /// specified pointer.  This always returns an integer value of size intptr_t.
 Value *LibCallOptimization::EmitStrLen(Value *Ptr, IRBuilder<> &B) {
   Module *M = Caller->getParent();
-  Constant *StrLen =M->getOrInsertFunction("strlen", TD->getIntPtrType(),
+  AttributeWithIndex AWI[2];
+  AWI[0] = AttributeWithIndex::get(1, Attribute::NoCapture);
+  AWI[1] = AttributeWithIndex::get(~0u, Attribute::ReadOnly |
+                                   Attribute::NoUnwind);
+
+  Constant *StrLen =M->getOrInsertFunction("strlen", AttrListPtr::get(AWI, 2),
+                                           TD->getIntPtrType(),
                                            PointerType::getUnqual(Type::Int8Ty),
                                            NULL);
   return B.CreateCall(StrLen, CastToCStr(Ptr, B), "strlen");
@@ -147,7 +153,10 @@ Value *LibCallOptimization::EmitMemCpy(Value *Dst, Value *Src, Value *Len,
 Value *LibCallOptimization::EmitMemChr(Value *Ptr, Value *Val,
                                        Value *Len, IRBuilder<> &B) {
   Module *M = Caller->getParent();
-  Value *MemChr = M->getOrInsertFunction("memchr",
+  AttributeWithIndex AWI;
+  AWI = AttributeWithIndex::get(~0u, Attribute::ReadOnly | Attribute::NoUnwind);
+
+  Value *MemChr = M->getOrInsertFunction("memchr", AttrListPtr::get(&AWI, 1),
                                          PointerType::getUnqual(Type::Int8Ty),
                                          PointerType::getUnqual(Type::Int8Ty),
                                          Type::Int32Ty, TD->getIntPtrType(),
@@ -159,7 +168,13 @@ Value *LibCallOptimization::EmitMemChr(Value *Ptr, Value *Val,
 Value *LibCallOptimization::EmitMemCmp(Value *Ptr1, Value *Ptr2,
                                        Value *Len, IRBuilder<> &B) {
   Module *M = Caller->getParent();
-  Value *MemCmp = M->getOrInsertFunction("memcmp",
+  AttributeWithIndex AWI[3];
+  AWI[0] = AttributeWithIndex::get(1, Attribute::NoCapture);
+  AWI[1] = AttributeWithIndex::get(2, Attribute::NoCapture);
+  AWI[2] = AttributeWithIndex::get(~0u, Attribute::ReadOnly |
+                                   Attribute::NoUnwind);
+
+  Value *MemCmp = M->getOrInsertFunction("memcmp", AttrListPtr::get(AWI, 3),
                                          Type::Int32Ty,
                                          PointerType::getUnqual(Type::Int8Ty),
                                          PointerType::getUnqual(Type::Int8Ty),
@@ -207,7 +222,12 @@ void LibCallOptimization::EmitPutChar(Value *Char, IRBuilder<> &B) {
 /// some pointer.
 void LibCallOptimization::EmitPutS(Value *Str, IRBuilder<> &B) {
   Module *M = Caller->getParent();
-  Value *F = M->getOrInsertFunction("puts", Type::Int32Ty,
+  AttributeWithIndex AWI[2];
+  AWI[0] = AttributeWithIndex::get(1, Attribute::NoCapture);
+  AWI[1] = AttributeWithIndex::get(~0u, Attribute::NoUnwind);
+
+  Value *F = M->getOrInsertFunction("puts", AttrListPtr::get(AWI, 2),
+                                    Type::Int32Ty,
                                     PointerType::getUnqual(Type::Int8Ty), NULL);
   B.CreateCall(F, CastToCStr(Str, B), "puts");
 }
@@ -216,8 +236,17 @@ void LibCallOptimization::EmitPutS(Value *Str, IRBuilder<> &B) {
 /// an integer and File is a pointer to FILE.
 void LibCallOptimization::EmitFPutC(Value *Char, Value *File, IRBuilder<> &B) {
   Module *M = Caller->getParent();
-  Constant *F = M->getOrInsertFunction("fputc", Type::Int32Ty, Type::Int32Ty,
-                                       File->getType(), NULL);
+  AttributeWithIndex AWI[2];
+  AWI[0] = AttributeWithIndex::get(2, Attribute::NoCapture);
+  AWI[1] = AttributeWithIndex::get(~0u, Attribute::NoUnwind);
+  Constant *F;
+  if (isa<PointerType>(File->getType()))
+    F = M->getOrInsertFunction("fputc", AttrListPtr::get(AWI, 2), Type::Int32Ty,
+                               Type::Int32Ty, File->getType(), NULL);
+                                         
+  else
+    F = M->getOrInsertFunction("fputc", Type::Int32Ty, Type::Int32Ty,
+                               File->getType(), NULL);
   Char = B.CreateIntCast(Char, Type::Int32Ty, "chari");
   B.CreateCall2(F, Char, File, "fputc");
 }
@@ -226,9 +255,18 @@ void LibCallOptimization::EmitFPutC(Value *Char, Value *File, IRBuilder<> &B) {
 /// pointer and File is a pointer to FILE.
 void LibCallOptimization::EmitFPutS(Value *Str, Value *File, IRBuilder<> &B) {
   Module *M = Caller->getParent();
-  Constant *F = M->getOrInsertFunction("fputs", Type::Int32Ty,
-                                       PointerType::getUnqual(Type::Int8Ty),
-                                       File->getType(), NULL);
+  AttributeWithIndex AWI[2];
+  AWI[0] = AttributeWithIndex::get(2, Attribute::NoCapture);
+  AWI[1] = AttributeWithIndex::get(~0u, Attribute::NoUnwind);
+  Constant *F;
+  if (isa<PointerType>(File->getType()))
+    F = M->getOrInsertFunction("fputs", AttrListPtr::get(AWI, 2), Type::Int32Ty,
+                               PointerType::getUnqual(Type::Int8Ty),
+                               File->getType(), NULL);
+  else
+    F = M->getOrInsertFunction("fputs", Type::Int32Ty,
+                               PointerType::getUnqual(Type::Int8Ty),
+                               File->getType(), NULL);
   B.CreateCall2(F, CastToCStr(Str, B), File, "fputs");
 }
 
@@ -237,10 +275,22 @@ void LibCallOptimization::EmitFPutS(Value *Str, Value *File, IRBuilder<> &B) {
 void LibCallOptimization::EmitFWrite(Value *Ptr, Value *Size, Value *File,
                                      IRBuilder<> &B) {
   Module *M = Caller->getParent();
-  Constant *F = M->getOrInsertFunction("fwrite", TD->getIntPtrType(),
-                                       PointerType::getUnqual(Type::Int8Ty),
-                                       TD->getIntPtrType(), TD->getIntPtrType(),
-                                       File->getType(), NULL);
+  AttributeWithIndex AWI[3];
+  AWI[0] = AttributeWithIndex::get(1, Attribute::NoCapture);
+  AWI[1] = AttributeWithIndex::get(4, Attribute::NoCapture);
+  AWI[2] = AttributeWithIndex::get(~0u, Attribute::NoUnwind);
+  Constant *F;
+  if (isa<PointerType>(File->getType()))
+    F = M->getOrInsertFunction("fwrite", AttrListPtr::get(AWI, 3),
+                               TD->getIntPtrType(),
+                               PointerType::getUnqual(Type::Int8Ty),
+                               TD->getIntPtrType(), TD->getIntPtrType(),
+                               File->getType(), NULL);
+  else
+    F = M->getOrInsertFunction("fwrite", TD->getIntPtrType(),
+                               PointerType::getUnqual(Type::Int8Ty),
+                               TD->getIntPtrType(), TD->getIntPtrType(),
+                               File->getType(), NULL);
   B.CreateCall4(F, CastToCStr(Ptr, B), Size, 
                 ConstantInt::get(TD->getIntPtrType(), 1), File);
 }
@@ -1290,7 +1340,7 @@ namespace {
     SPrintFOpt SPrintF; PrintFOpt PrintF;
     FWriteOpt FWrite; FPutsOpt FPuts; FPrintFOpt FPrintF;
 
-    bool Modified;  // This is only used by doFinalization.
+    bool Modified;  // This is only used by doInitialization.
   public:
     static char ID; // Pass identification
     SimplifyLibCalls() : FunctionPass(&ID) {}
@@ -1303,7 +1353,7 @@ namespace {
     void setDoesNotThrow(Function &F);
     void setDoesNotCapture(Function &F, unsigned n);
     void setDoesNotAlias(Function &F, unsigned n);
-    bool doFinalization(Module &M);
+    bool doInitialization(Module &M);
 
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.addRequired<TargetData>();
@@ -1450,7 +1500,7 @@ bool SimplifyLibCalls::runOnFunction(Function &F) {
   return Changed;
 }
 
-// Utility methods for doFinalization.
+// Utility methods for doInitialization.
 
 void SimplifyLibCalls::setDoesNotAccessMemory(Function &F) {
   if (!F.doesNotAccessMemory()) {
@@ -1488,9 +1538,9 @@ void SimplifyLibCalls::setDoesNotAlias(Function &F, unsigned n) {
   }
 }
 
-/// doFinalization - Add attributes to well-known functions.
+/// doInitialization - Add attributes to well-known functions.
 ///
-bool SimplifyLibCalls::doFinalization(Module &M) {
+bool SimplifyLibCalls::doInitialization(Module &M) {
   Modified = false;
   for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
     Function &F = *I;
@@ -1584,6 +1634,15 @@ bool SimplifyLibCalls::doFinalization(Module &M) {
           setDoesNotThrow(F);
           setDoesNotCapture(F, 1);
           setDoesNotCapture(F, 2);
+        } else if ((NameLen == 6 && !strcmp(NameStr, "strdup")) ||
+                   (NameLen == 7 && !strcmp(NameStr, "strndup"))) {
+          if (FTy->getNumParams() < 1 ||
+              !isa<PointerType>(FTy->getReturnType()) ||
+              !isa<PointerType>(FTy->getParamType(0)))
+            continue;
+          setDoesNotThrow(F);
+          setDoesNotAlias(F, 0);
+          setDoesNotCapture(F, 1);
         }
         break;
       case 'm':