[AVX] Make Inits Foldable

Manage Inits in a FoldingSet.  This provides several benefits:

- Memory for Inits is properly managed

- Duplicate Inits are folded into Flyweights, saving memory

- It enforces const-correctness, protecting against certain classes
  of bugs

The above benefits allow Inits to be used in more contexts, which in
turn provides more dynamism to TableGen.  This enhanced capability
will be used by the AVX code generator to a fold common patterns
together.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134907 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 6 deletions

diff --git a/utils/TableGen/DAGISelMatcherGen.cpp b/utils/TableGen/DAGISelMatcherGen.cpp
index c5897c72d3..1c841252e9 100644
--- a/utils/TableGen/DAGISelMatcherGen.cpp
+++ b/utils/TableGen/DAGISelMatcherGen.cpp
@@ -203,7 +203,7 @@ void MatcherGen::EmitLeafMatchCode(const TreePatternNode *N) {
   assert(N->isLeaf() && "Not a leaf?");
 
   // Direct match against an integer constant.
-  if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue())) {
+  if (const IntInit *II = dynamic_cast<const IntInit*>(N->getLeafValue())) {
     // If this is the root of the dag we're matching, we emit a redundant opcode
     // check to ensure that this gets folded into the normal top-level
     // OpcodeSwitch.
@@ -215,7 +215,7 @@ void MatcherGen::EmitLeafMatchCode(const TreePatternNode *N) {
     return AddMatcher(new CheckIntegerMatcher(II->getValue()));
   }
 
-  DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue());
+  const DefInit *DI = dynamic_cast<const DefInit*>(N->getLeafValue());
   if (DI == 0) {
     errs() << "Unknown leaf kind: " << *DI << "\n";
     abort();
@@ -283,7 +283,8 @@ void MatcherGen::EmitOperatorMatchCode(const TreePatternNode *N,
        N->getOperator()->getName() == "or") &&
       N->getChild(1)->isLeaf() && N->getChild(1)->getPredicateFns().empty() &&
       N->getPredicateFns().empty()) {
-    if (IntInit *II = dynamic_cast<IntInit*>(N->getChild(1)->getLeafValue())) {
+    if (const IntInit *II =
+        dynamic_cast<const IntInit*>(N->getChild(1)->getLeafValue())) {
       if (!isPowerOf2_32(II->getValue())) {  // Don't bother with single bits.
         // If this is at the root of the pattern, we emit a redundant
         // CheckOpcode so that the following checks get factored properly under
@@ -496,7 +497,7 @@ bool MatcherGen::EmitMatcherCode(unsigned Variant) {
     --RecNodeEntry;  // Entries in VariableMap are biased.
 
     const ComplexPattern &CP =
-      CGP.getComplexPattern(((DefInit*)N->getLeafValue())->getDef());
+      CGP.getComplexPattern(((const DefInit*)N->getLeafValue())->getDef());
 
     // Emit a CheckComplexPat operation, which does the match (aborting if it
     // fails) and pushes the matched operands onto the recorded nodes list.
@@ -572,14 +573,14 @@ void MatcherGen::EmitResultLeafAsOperand(const TreePatternNode *N,
                                          SmallVectorImpl<unsigned> &ResultOps) {
   assert(N->isLeaf() && "Must be a leaf");
 
-  if (IntInit *II = dynamic_cast<IntInit*>(N->getLeafValue())) {
+  if (const IntInit *II = dynamic_cast<const IntInit*>(N->getLeafValue())) {
     AddMatcher(new EmitIntegerMatcher(II->getValue(), N->getType(0)));
     ResultOps.push_back(NextRecordedOperandNo++);
     return;
   }
 
   // If this is an explicit register reference, handle it.
-  if (DefInit *DI = dynamic_cast<DefInit*>(N->getLeafValue())) {
+  if (const DefInit *DI = dynamic_cast<const DefInit*>(N->getLeafValue())) {
     Record *Def = DI->getDef();
     if (Def->isSubClassOf("Register")) {
       const CodeGenRegister *Reg =