Allow ComplexExpressions in InstrInfo.td files to be slightly more... complex! ComplexExpressions can now have attributes which affect how TableGen interprets

the pattern when generating matchin code. 

The first (and currently, only) attribute causes the immediate parent node of the ComplexPattern operand to be passed into the matching code rather than the node at the root of the entire DAG containing the pattern.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46606 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 28 insertions, 6 deletions

diff --git a/utils/TableGen/CodeGenTarget.cpp b/utils/TableGen/CodeGenTarget.cpp
index cf33fe6b1a..bc758b75cd 100644
--- a/utils/TableGen/CodeGenTarget.cpp
+++ b/utils/TableGen/CodeGenTarget.cpp
@@ -351,6 +351,18 @@ ComplexPattern::ComplexPattern(Record *R) {
            << "' on ComplexPattern '" << R->getName() << "'!\n";
       exit(1);
     }
+  
+  // Parse the attributes.  
+  Attributes = 0;
+  PropList = R->getValueAsListOfDefs("Attributes");
+  for (unsigned i = 0, e = PropList.size(); i != e; ++i)
+    if (PropList[i]->getName() == "CPAttrParentAsRoot") {
+      Attributes |= 1 << CPAttrParentAsRoot;
+    } else {
+      cerr << "Unsupported pattern attribute '" << PropList[i]->getName()
+           << "' on ComplexPattern '" << R->getName() << "'!\n";
+      exit(1);
+    }
 }
 
 //===----------------------------------------------------------------------===//
diff --git a/utils/TableGen/CodeGenTarget.h b/utils/TableGen/CodeGenTarget.h
index 922c2b41a1..a14f6303bd 100644
--- a/utils/TableGen/CodeGenTarget.h
+++ b/utils/TableGen/CodeGenTarget.h
@@ -42,6 +42,9 @@ enum SDNP {
   SDNPSideEffect
 };
 
+// ComplexPattern attributes.
+enum CPAttr { CPAttrParentAsRoot };
+
 /// getValueType - Return the MVT::ValueType that the specified TableGen record
 /// corresponds to.
 MVT::ValueType getValueType(Record *Rec);
@@ -172,7 +175,8 @@ class ComplexPattern {
   unsigned NumOperands;
   std::string SelectFunc;
   std::vector<Record*> RootNodes;
-  unsigned Properties;
+  unsigned Properties; // Node properties
+  unsigned Attributes; // Pattern attributes
 public:
   ComplexPattern() : NumOperands(0) {};
   ComplexPattern(Record *R);
@@ -184,7 +188,7 @@ public:
     return RootNodes;
   }
   bool hasProperty(enum SDNP Prop) const { return Properties & (1 << Prop); }
-
+  bool hasAttribute(enum CPAttr Attr) const { return Attributes & (1 << Attr); }
 };
 
 } // End llvm namespace
diff --git a/utils/TableGen/DAGISelEmitter.cpp b/utils/TableGen/DAGISelEmitter.cpp
index d685f701f0..1f568ad5ee 100644
--- a/utils/TableGen/DAGISelEmitter.cpp
+++ b/utils/TableGen/DAGISelEmitter.cpp
@@ -550,7 +550,7 @@ public:
           emitCheck(MaskPredicate + RootName + "0, cast<ConstantSDNode>(" +
                     RootName + "1), " + itostr(II->getValue()) + ")");
           
-          EmitChildMatchCode(N->getChild(0), N, RootName + utostr(0),
+          EmitChildMatchCode(N->getChild(0), N, RootName + utostr(0), RootName,
                              ChainSuffix + utostr(0), FoundChain);
           return;
         }
@@ -561,7 +561,7 @@ public:
       emitInit("SDOperand " + RootName + utostr(OpNo) + " = " +
                RootName + ".getOperand(" +utostr(OpNo) + ");");
 
-      EmitChildMatchCode(N->getChild(i), N, RootName + utostr(OpNo),
+      EmitChildMatchCode(N->getChild(i), N, RootName + utostr(OpNo), RootName,
                          ChainSuffix + utostr(OpNo), FoundChain);
     }
 
@@ -593,7 +593,8 @@ public:
   }
 
   void EmitChildMatchCode(TreePatternNode *Child, TreePatternNode *Parent,
-                          const std::string &RootName,
+                          const std::string &RootName, 
+                          const std::string &ParentRootName,
                           const std::string &ChainSuffix, bool &FoundChain) {
     if (!Child->isLeaf()) {
       // If it's not a leaf, recursively match.
@@ -649,7 +650,12 @@ public:
             emitCode("SDOperand " + ChainName + ";");
           }
           
-          std::string Code = Fn + "(N, ";
+          std::string Code = Fn + "(";
+          if (CP->hasAttribute(CPAttrParentAsRoot)) {
+            Code += ParentRootName + ", ";
+          } else {
+            Code += "N, ";
+          }
           if (CP->hasProperty(SDNPHasChain)) {
             std::string ParentName(RootName.begin(), RootName.end()-1);
             Code += ParentName + ", ";