commit 324c99dee5096be095adc3972c4a512ca0f74090
author Reid Kleckner <rnk@google.com> Mon Apr 10 20:18:10 2017 +0000
committer Reid Kleckner <rnk@google.com> Mon Apr 10 20:18:10 2017 +0000
tree 9719e54e4dcaa0633d5b1aa58dec3b98d5bebebd
parent 5be1176543aa4d1fca8dbac59c7908473b3447fc

[IR] Make AttributeSetNode public, avoid temporary AttributeList copies

Summary:
AttributeList::get(Fn|Ret|Param)Attributes no longer creates a temporary
AttributeList just to hide the AttributeSetNode type.

I've also added a factory method to create AttributeLists from a
parallel array of AttributeSetNodes. I think this simplifies
construction of AttributeLists when rewriting function prototypes.
Previously we would test if a particular index had attributes, and
conditionally add a temporary attribute list to a vector. Now the
attribute set vector is parallel to the argument vector already that
these passes already construct.

My long term vision is to wrap AttributeSetNode* inside an AttributeSet
type that holds the enum attributes, but that will come in a follow up
change.

I haven't done any performance measurements for this change because
profiling hasn't shown that any of the affected code is hot.

Reviewers: pete, chandlerc, sanjoy, hfinkel

Reviewed By: pete

Subscribers: jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D31198

llvm-svn: 299875

llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp

diff --git a/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp b/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
index 95e598a..84f76b6 100644
--- a/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
+++ b/llvm/lib/Transforms/Scalar/RewriteStatepointsForGC.cpp
@@ -1392,7 +1392,6 @@
 
   // Create the statepoint given all the arguments
   Instruction *Token = nullptr;
-  AttributeList ReturnAttrs;
   if (CS.isCall()) {
     CallInst *ToReplace = cast<CallInst>(CS.getInstruction());
     CallInst *Call = Builder.CreateGCStatepointCall(
@@ -1407,8 +1406,9 @@
     AttributeList NewAttrs = legalizeCallAttributes(ToReplace->getAttributes());
     // In case if we can handle this set of attributes - set up function attrs
     // directly on statepoint and return attrs later for gc_result intrinsic.
-    Call->setAttributes(NewAttrs.getFnAttributes());
-    ReturnAttrs = NewAttrs.getRetAttributes();
+    Call->setAttributes(AttributeList::get(Call->getContext(),
+                                           AttributeList::FunctionIndex,
+                                           NewAttrs.getFnAttributes()));
 
     Token = Call;
 
@@ -1435,8 +1435,9 @@
     AttributeList NewAttrs = legalizeCallAttributes(ToReplace->getAttributes());
     // In case if we can handle this set of attributes - set up function attrs
     // directly on statepoint and return attrs later for gc_result intrinsic.
-    Invoke->setAttributes(NewAttrs.getFnAttributes());
-    ReturnAttrs = NewAttrs.getRetAttributes();
+    Invoke->setAttributes(AttributeList::get(Invoke->getContext(),
+                                             AttributeList::FunctionIndex,
+                                             NewAttrs.getFnAttributes()));
 
     Token = Invoke;
 
@@ -1482,7 +1483,9 @@
       StringRef Name =
           CS.getInstruction()->hasName() ? CS.getInstruction()->getName() : "";
       CallInst *GCResult = Builder.CreateGCResult(Token, CS.getType(), Name);
-      GCResult->setAttributes(CS.getAttributes().getRetAttributes());
+      GCResult->setAttributes(
+          AttributeList::get(GCResult->getContext(), AttributeList::ReturnIndex,
+                             CS.getAttributes().getRetAttributes()));
 
       // We cannot RAUW or delete CS.getInstruction() because it could be in the
       // live set of some other safepoint, in which case that safepoint's