hoist some funky logic into CodeGenInstruction

from two places in CodeGenDAGPatterns.cpp, and
use it in DAGISelMatcherGen.cpp instead of using
an incorrect predicate that happened to get lucky
on our current targets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99726 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 38 insertions, 17 deletions

diff --git a/utils/TableGen/CodeGenDAGPatterns.cpp b/utils/TableGen/CodeGenDAGPatterns.cpp
index ba9a98d8dd..b030800c9e 100644
--- a/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -779,15 +779,9 @@ static unsigned GetNumNodeResults(Record *Operator, CodeGenDAGPatterns &CDP) {
     // FIXME: Should allow access to all the results here.
     unsigned NumDefsToAdd = InstInfo.NumDefs ? 1 : 0;
     
-    if (!InstInfo.ImplicitDefs.empty()) {
-      // Add on one implicit def if it has a resolvable type.
-      Record *FirstImplicitDef = InstInfo.ImplicitDefs[0];
-      assert(FirstImplicitDef->isSubClassOf("Register"));
-      const std::vector<MVT::SimpleValueType> &RegVTs = 
-      CDP.getTargetInfo().getRegisterVTs(FirstImplicitDef);
-      if (RegVTs.size() == 1)
-        return NumDefsToAdd+1;
-    }
+    // Add on one implicit def if it has a resolvable type.
+    if (InstInfo.HasOneImplicitDefWithKnownVT(CDP.getTargetInfo()) !=MVT::Other)
+      ++NumDefsToAdd;
     return NumDefsToAdd;
   }
   
@@ -1279,12 +1273,13 @@ bool TreePatternNode::ApplyTypeConstraints(TreePattern &TP, bool NotRegisters) {
     if (!InstInfo.ImplicitDefs.empty()) {
       unsigned ResNo = NumResultsToAdd;
       
-      Record *FirstImplicitDef = InstInfo.ImplicitDefs[0];
-      assert(FirstImplicitDef->isSubClassOf("Register"));
-      const std::vector<MVT::SimpleValueType> &RegVTs = 
-        CDP.getTargetInfo().getRegisterVTs(FirstImplicitDef);
-      if (RegVTs.size() == 1)   // FIXME: Generalize.
-        MadeChange |= UpdateNodeType(ResNo, EEVT::TypeSet(RegVTs), TP);
+      // FIXME: Generalize to multiple possible types and multiple possible
+      // ImplicitDefs.
+      MVT::SimpleValueType VT =
+        InstInfo.HasOneImplicitDefWithKnownVT(CDP.getTargetInfo());
+      
+      if (VT != MVT::Other)
+        MadeChange |= UpdateNodeType(ResNo, VT, TP);
     }
     
     // If this is an INSERT_SUBREG, constrain the source and destination VTs to
diff --git a/utils/TableGen/CodeGenInstruction.cpp b/utils/TableGen/CodeGenInstruction.cpp
index eea5561872..99d196c3ce 100644
--- a/utils/TableGen/CodeGenInstruction.cpp
+++ b/utils/TableGen/CodeGenInstruction.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "CodeGenInstruction.h"
+#include "CodeGenTarget.h"
 #include "Record.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/STLExtras.h"
@@ -294,3 +295,22 @@ CodeGenInstruction::ParseOperandName(const std::string &Op,
   // Otherwise, didn't find it!
   throw TheDef->getName() + ": unknown suboperand name in '" + Op + "'";
 }
+
+
+/// HasOneImplicitDefWithKnownVT - If the instruction has at least one
+/// implicit def and it has a known VT, return the VT, otherwise return
+/// MVT::Other.
+MVT::SimpleValueType CodeGenInstruction::
+HasOneImplicitDefWithKnownVT(const CodeGenTarget &TargetInfo) const {
+  if (ImplicitDefs.empty()) return MVT::Other;
+  
+  // Check to see if the first implicit def has a resolvable type.
+  Record *FirstImplicitDef = ImplicitDefs[0];
+  assert(FirstImplicitDef->isSubClassOf("Register"));
+  const std::vector<MVT::SimpleValueType> &RegVTs = 
+    TargetInfo.getRegisterVTs(FirstImplicitDef);
+  if (RegVTs.size() == 1)
+    return RegVTs[0];
+  return MVT::Other;
+}
+
diff --git a/utils/TableGen/CodeGenInstruction.h b/utils/TableGen/CodeGenInstruction.h
index c369123dd6..946c2d01a5 100644
--- a/utils/TableGen/CodeGenInstruction.h
+++ b/utils/TableGen/CodeGenInstruction.h
@@ -22,6 +22,7 @@
 namespace llvm {
   class Record;
   class DagInit;
+  class CodeGenTarget;
 
   class CodeGenInstruction {
   public:
@@ -183,6 +184,12 @@ namespace llvm {
     /// non-empty name.  If the instruction does not have an operand with the
     /// specified name, throw an exception.
     unsigned getOperandNamed(const std::string &Name) const;
+    
+    /// HasOneImplicitDefWithKnownVT - If the instruction has at least one
+    /// implicit def and it has a known VT, return the VT, otherwise return
+    /// MVT::Other.
+    MVT::SimpleValueType 
+      HasOneImplicitDefWithKnownVT(const CodeGenTarget &TargetInfo) const;
   };
 }
 
diff --git a/utils/TableGen/DAGISelMatcherGen.cpp b/utils/TableGen/DAGISelMatcherGen.cpp
index f7fd493cd3..f0f8706489 100644
--- a/utils/TableGen/DAGISelMatcherGen.cpp
+++ b/utils/TableGen/DAGISelMatcherGen.cpp
@@ -733,8 +733,7 @@ EmitResultInstructionAsOperand(const TreePatternNode *N,
     // If the root came from an implicit def in the instruction handling stuff,
     // don't re-add it.
     Record *HandledReg = 0;
-    if (N->getNumTypes() != 0 &&
-        !II.ImplicitDefs.empty())
+    if (II.HasOneImplicitDefWithKnownVT(CGT) != MVT::Other)
       HandledReg = II.ImplicitDefs[0];
     
     for (unsigned i = 0; i != Pattern.getDstRegs().size(); ++i) {