From: Sean Silva <silvas@purdue.edu>
Date: Wed, 19 Sep 2012 01:47:03 +0000 (+0000)
Subject: Iterate deterministicaly over ClassInfo*'s
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=b2df610b44902124c22f3661a39bffd5341da62d;p=oota-llvm.git

Iterate deterministicaly over ClassInfo*'s

Fixes an observed instance of nondeterministic TableGen output.

Review by Jakob.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164191 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/utils/TableGen/AsmMatcherEmitter.cpp b/utils/TableGen/AsmMatcherEmitter.cpp
index b8deba384b9..fa4987f43be 100644
--- a/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/utils/TableGen/AsmMatcherEmitter.cpp
@@ -279,6 +279,15 @@ public:
   }
 };
 
+namespace {
+/// Sort ClassInfo pointers independently of pointer value.
+struct LessClassInfoPtr {
+  bool operator()(const ClassInfo *LHS, const ClassInfo *RHS) const {
+    return *LHS < *RHS;
+  }
+};
+}
+
 /// MatchableInfo - Helper class for storing the necessary information for an
 /// instruction or alias which is capable of being matched.
 struct MatchableInfo {
@@ -1240,7 +1249,8 @@ void AsmMatcherInfo::buildOperandMatchInfo() {
 
   /// Map containing a mask with all operands indices that can be found for
   /// that class inside a instruction.
-  std::map<ClassInfo*, unsigned> OpClassMask;
+  typedef std::map<ClassInfo*, unsigned, LessClassInfoPtr> OpClassMaskTy;
+  OpClassMaskTy OpClassMask;
 
   for (std::vector<MatchableInfo*>::const_iterator it =
        Matchables.begin(), ie = Matchables.end();
@@ -1259,7 +1269,7 @@ void AsmMatcherInfo::buildOperandMatchInfo() {
     }
 
     // Generate operand match info for each mnemonic/operand class pair.
-    for (std::map<ClassInfo*, unsigned>::iterator iit = OpClassMask.begin(),
+    for (OpClassMaskTy::iterator iit = OpClassMask.begin(),
          iie = OpClassMask.end(); iit != iie; ++iit) {
       unsigned OpMask = iit->second;
       ClassInfo *CI = iit->first;