split the movechild/record/moveparent -> recordchild optzn into a

movechild/record -> recordchild/movechild and 
movechild/moveparent -> noop xforms.  This slightly shrinks the tables
(x86 to 117454) and enables adding future improvements.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97051 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 16 deletions

diff --git a/utils/TableGen/DAGISelMatcherOpt.cpp b/utils/TableGen/DAGISelMatcherOpt.cpp
index d3658202a6..408bd63e33 100644
--- a/utils/TableGen/DAGISelMatcherOpt.cpp
+++ b/utils/TableGen/DAGISelMatcherOpt.cpp
@@ -14,35 +14,41 @@
 #include "DAGISelMatcher.h"
 using namespace llvm;
 
-
-static void FormRecordChildNodes(OwningPtr<MatcherNode> &Matcher) {
+static void ContractNodes(OwningPtr<MatcherNode> &Matcher) {
   // If we reached the end of the chain, we're done.
   MatcherNode *N = Matcher.get();
   if (N == 0) return;
   
   // If we have a push node, walk down both edges.
   if (PushMatcherNode *Push = dyn_cast<PushMatcherNode>(N))
-    FormRecordChildNodes(Push->getFailurePtr());
+    ContractNodes(Push->getFailurePtr());
   
-  // If we found a movechild node, check to see if our pattern matches.
+  // If we found a movechild node with a node that comes in a 'foochild' form,
+  // transform it.
   if (MoveChildMatcherNode *MC = dyn_cast<MoveChildMatcherNode>(N)) {
-    if (RecordMatcherNode *RM = dyn_cast<RecordMatcherNode>(MC->getNext()))
-      if (MoveParentMatcherNode *MP = 
-                 dyn_cast<MoveParentMatcherNode>(RM->getNext())) {
-        MatcherNode *New
-          = new RecordChildMatcherNode(MC->getChildNo(), RM->getWhatFor());
-        New->setNext(MP->takeNext());
-        Matcher.reset(New);
-        return FormRecordChildNodes(Matcher);
-      }
+    if (RecordMatcherNode *RM = dyn_cast<RecordMatcherNode>(MC->getNext())) {
+      MatcherNode *New
+        = new RecordChildMatcherNode(MC->getChildNo(), RM->getWhatFor());
+      New->setNext(Matcher.take());
+      Matcher.reset(New);
+      MC->setNext(RM->takeNext());
+      return ContractNodes(Matcher);
+    }
   }
-
-  FormRecordChildNodes(N->getNextPtr());
+  
+  if (MoveChildMatcherNode *MC = dyn_cast<MoveChildMatcherNode>(N))
+    if (MoveParentMatcherNode *MP = 
+          dyn_cast<MoveParentMatcherNode>(MC->getNext())) {
+      Matcher.reset(MP->takeNext());
+      return ContractNodes(Matcher);
+    }
+  
+  ContractNodes(N->getNextPtr());
 }
 
 
 MatcherNode *llvm::OptimizeMatcher(MatcherNode *Matcher) {
   OwningPtr<MatcherNode> MatcherPtr(Matcher);
-  FormRecordChildNodes(MatcherPtr);
+  ContractNodes(MatcherPtr);
   return MatcherPtr.take();
 }