[llvm] r374694 - [Attributor][FIX] Avoid modifying naked/optnone functions

[Johannes Doerfert via llvm-commits]

Author: jdoerfert
Date: Sat Oct 12 19:24:02 2019
New Revision: 374694

URL: http://llvm.org/viewvc/llvm-project?rev=374694&view=rev
Log:
[Attributor][FIX] Avoid modifying naked/optnone functions

The check for naked/optnone was insufficient for different reasons. We
now check before we initialize an abstract attribute and we do it for
all abstract attributes.

Modified:
    llvm/trunk/include/llvm/Transforms/IPO/Attributor.h
    llvm/trunk/lib/Transforms/IPO/Attributor.cpp
    llvm/trunk/test/Transforms/FunctionAttrs/nonnull.ll

Modified: llvm/trunk/include/llvm/Transforms/IPO/Attributor.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/IPO/Attributor.h?rev=374694&r1=374693&r2=374694&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/IPO/Attributor.h (original)
+++ llvm/trunk/include/llvm/Transforms/IPO/Attributor.h Sat Oct 12 19:24:02 2019
@@ -913,15 +913,23 @@ private:
     // Use the static create method.
     auto &AA = AAType::createForPosition(IRP, *this);
     registerAA(AA);
-    AA.initialize(*this);
+
+    // For now we ignore naked and optnone functions.
+    bool Invalidate = Whitelist && !Whitelist->count(&AAType::ID);
+    if (const Function *Fn = IRP.getAnchorScope())
+      Invalidate |= Fn->hasFnAttribute(Attribute::Naked) ||
+                    Fn->hasFnAttribute(Attribute::OptimizeNone);
 
     // Bootstrap the new attribute with an initial update to propagate
     // information, e.g., function -> call site. If it is not on a given
     // whitelist we will not perform updates at all.
-    if (Whitelist && !Whitelist->count(&AAType::ID))
+    if (Invalidate) {
       AA.getState().indicatePessimisticFixpoint();
-    else
-      AA.update(*this);
+      return AA;
+    }
+
+    AA.initialize(*this);
+    AA.update(*this);
 
     if (TrackDependence && AA.getState().isValidState())
       QueryMap[&AA].insert(const_cast<AbstractAttribute *>(QueryingAA));

Modified: llvm/trunk/lib/Transforms/IPO/Attributor.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/Attributor.cpp?rev=374694&r1=374693&r2=374694&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/IPO/Attributor.cpp (original)
+++ llvm/trunk/lib/Transforms/IPO/Attributor.cpp Sat Oct 12 19:24:02 2019
@@ -4847,11 +4847,6 @@ static bool runAttributorOnModule(Module
     else
       NumFnWithoutExactDefinition++;
 
-    // For now we ignore naked and optnone functions.
-    if (F.hasFnAttribute(Attribute::Naked) ||
-        F.hasFnAttribute(Attribute::OptimizeNone))
-      continue;
-
     // We look at internal functions only on-demand but if any use is not a
     // direct call, we have to do it eagerly.
     if (F.hasLocalLinkage()) {

Modified: llvm/trunk/test/Transforms/FunctionAttrs/nonnull.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/FunctionAttrs/nonnull.ll?rev=374694&r1=374693&r2=374694&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/FunctionAttrs/nonnull.ll (original)
+++ llvm/trunk/test/Transforms/FunctionAttrs/nonnull.ll Sat Oct 12 19:24:02 2019
@@ -545,6 +545,30 @@ define weak_odr void @weak_caller(i32* n
   ret void
 }
 
+; Expect nonnull
+; ATTRIBUTOR: define internal void @control(i32* nocapture nonnull readnone align 16 dereferenceable(8) %a)
+define internal void @control(i32* dereferenceable(4) %a) {
+  call void @use_i32_ptr(i32* %a)
+  ret void
+}
+; Avoid nonnull as we do not touch naked functions
+; ATTRIBUTOR: define internal void @naked(i32* dereferenceable(4) %a)
+define internal void @naked(i32* dereferenceable(4) %a) naked {
+  call void @use_i32_ptr(i32* %a)
+  ret void
+}
+; Avoid nonnull as we do not touch optnone
+; ATTRIBUTOR: define internal void @optnone(i32* dereferenceable(4) %a)
+define internal void @optnone(i32* dereferenceable(4) %a) optnone noinline {
+  call void @use_i32_ptr(i32* %a)
+  ret void
+}
+define void @make_live(i32* nonnull dereferenceable(8) %a) {
+  call void @naked(i32* nonnull dereferenceable(8) align 16 %a)
+  call void @control(i32* nonnull dereferenceable(8) align 16 %a)
+  call void @optnone(i32* nonnull dereferenceable(8) align 16 %a)
+  ret void
+}
 
 attributes #0 = { "null-pointer-is-valid"="true" }
 attributes #1 = { nounwind willreturn}