From 26e763753be5f3422a892f6c268721eae7792eac Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Fri, 19 Mar 2010 22:40:56 +0000
Subject: [PATCH] Change intrinsic result type for void to store it as an empty
 list instead of as a single element list with VoidTy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99009 91177308-0d34-0410-b5e6-96231b3b80d8
---
 utils/TableGen/CodeGenDAGPatterns.cpp | 12 +++---------
 utils/TableGen/CodeGenTarget.cpp      |  9 ++++++---
 utils/TableGen/IntrinsicEmitter.cpp   | 13 +++++++------
 3 files changed, 16 insertions(+), 18 deletions(-)

diff --git a/utils/TableGen/CodeGenDAGPatterns.cpp b/utils/TableGen/CodeGenDAGPatterns.cpp
index 00b6fe2200d..710b2ab0613 100644
--- a/utils/TableGen/CodeGenDAGPatterns.cpp
+++ b/utils/TableGen/CodeGenDAGPatterns.cpp
@@ -754,12 +754,8 @@ static unsigned GetNumNodeResults(Record *Operator, CodeGenDAGPatterns &CDP) {
       Operator->getName() == "parallel")
     return 0;  // All return nothing.
   
-  if (Operator->isSubClassOf("Intrinsic")) {
-    unsigned NumRes = CDP.getIntrinsic(Operator).IS.RetVTs.size();
-    if (NumRes == 1 && CDP.getIntrinsic(Operator).IS.RetVTs[0] == MVT::isVoid)
-      return 0;
-    return NumRes;
-  }
+  if (Operator->isSubClassOf("Intrinsic"))
+    return CDP.getIntrinsic(Operator).IS.RetVTs.size();
   
   if (Operator->isSubClassOf("SDNode"))
     return CDP.getSDNodeInfo(Operator).getNumResults();
@@ -1210,8 +1206,6 @@ bool TreePatternNode::ApplyTypeConstraints(TreePattern &TP, bool NotRegisters) {
     // Apply the result type to the node.
     unsigned NumRetVTs = Int->IS.RetVTs.size();
     unsigned NumParamVTs = Int->IS.ParamVTs.size();
-    if (NumRetVTs == 1 && Int->IS.RetVTs[0] == MVT::isVoid)
-      NumRetVTs = 0;
     
     for (unsigned i = 0, e = NumRetVTs; i != e; ++i)
       MadeChange |= UpdateNodeType(i, Int->IS.RetVTs[i], TP);
@@ -1591,7 +1585,7 @@ TreePatternNode *TreePattern::ParseTreePattern(DagInit *Dag) {
 
     // If this intrinsic returns void, it must have side-effects and thus a
     // chain.
-    if (Int.IS.RetVTs[0] == MVT::isVoid) {
+    if (Int.IS.RetVTs.empty()) {
       Operator = getDAGPatterns().get_intrinsic_void_sdnode();
     } else if (Int.ModRef != CodeGenIntrinsic::NoMem) {
       // Has side-effects, requires chain.
diff --git a/utils/TableGen/CodeGenTarget.cpp b/utils/TableGen/CodeGenTarget.cpp
index 79bc30d8c9a..0d29a2f3557 100644
--- a/utils/TableGen/CodeGenTarget.cpp
+++ b/utils/TableGen/CodeGenTarget.cpp
@@ -490,12 +490,15 @@ CodeGenIntrinsic::CodeGenIntrinsic(Record *R) {
       OverloadedVTs.push_back(VT);
       isOverloaded |= true;
     }
+    
     IS.RetVTs.push_back(VT);
     IS.RetTypeDefs.push_back(TyEl);
   }
-
-  if (IS.RetVTs.size() == 0)
-    throw "Intrinsic '"+DefName+"' needs at least a type for the ret value!";
+  
+  if (IS.RetVTs.size() == 1 && IS.RetVTs[0] == MVT::isVoid) {
+    IS.RetVTs.pop_back();
+    IS.RetTypeDefs.pop_back();
+  }
 
   // Parse the list of parameter types.
   TypeList = R->getValueAsListInit("ParamTypes");
diff --git a/utils/TableGen/IntrinsicEmitter.cpp b/utils/TableGen/IntrinsicEmitter.cpp
index c5df9e411c6..417aca7cb37 100644
--- a/utils/TableGen/IntrinsicEmitter.cpp
+++ b/utils/TableGen/IntrinsicEmitter.cpp
@@ -172,10 +172,11 @@ static void EmitTypeGenerate(raw_ostream &OS, const Record *ArgType,
 static void EmitTypeGenerate(raw_ostream &OS,
                              const std::vector<Record*> &ArgTypes,
                              unsigned &ArgNo) {
-  if (ArgTypes.size() == 1) {
-    EmitTypeGenerate(OS, ArgTypes.front(), ArgNo);
-    return;
-  }
+  if (ArgTypes.empty())
+    return EmitTypeForValueType(OS, MVT::isVoid);
+  
+  if (ArgTypes.size() == 1)
+    return EmitTypeGenerate(OS, ArgTypes.front(), ArgNo);
 
   OS << "StructType::get(Context, ";
 
@@ -251,11 +252,11 @@ namespace {
       unsigned RHSSize = RHSVec->size();
       unsigned LHSSize = LHSVec->size();
 
-      do {
+      for (; i != LHSSize; ++i) {
         if (i == RHSSize) return false;  // RHS is shorter than LHS.
         if ((*LHSVec)[i] != (*RHSVec)[i])
           return (*LHSVec)[i]->getName() < (*RHSVec)[i]->getName();
-      } while (++i != LHSSize);
+      }
 
       if (i != RHSSize) return true;