* We were forgetting to pass varargs arguments through a call

[oota-llvm.git] / lib / Transforms / Scalar / GCSE.cpp

diff --git a/lib/Transforms/Scalar/GCSE.cpp b/lib/Transforms/Scalar/GCSE.cpp
index 771b9690fad43584d89c9fc28d39bf8861af86b9..caf68bc1c8def5b544bfeacff94e5bddfbe677f1 100644 (file)
--- a/lib/Transforms/Scalar/GCSE.cpp
+++ b/lib/Transforms/Scalar/GCSE.cpp
@@ -1,4 +1,11 @@
 //===-- GCSE.cpp - SSA based Global Common Subexpr Elimination ------------===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
 //
 // This pass is designed to be a very quick global transformation that
 // eliminates global common subexpressions from a function.  It does this by
@@ -25,9 +32,6 @@ namespace {
   class GCSE : public FunctionPass {
     std::set<Instruction*>  WorkList;
     DominatorSet           *DomSetInfo;
-#if 0
-    ImmediateDominators    *ImmDominator;
-#endif
     ValueNumbering         *VN;
   public:
     virtual bool runOnFunction(Function &F);
@@ -61,9 +65,6 @@ bool GCSE::runOnFunction(Function &F) {
 
   // Get pointers to the analysis results that we will be using...
   DomSetInfo = &getAnalysis<DominatorSet>();
-#if 0
-  ImmDominator = &getAnalysis<ImmediateDominators>();
-#endif
   VN = &getAnalysis<ValueNumbering>();
 
   // Step #1: Add all instructions in the function to the worklist for
@@ -126,6 +127,7 @@ bool GCSE::EliminateRedundancies(Instruction *I,
 
           // Erase the instruction from the program.
           I->getParent()->getInstList().erase(I);
+          WorkList.erase(I);
         }
       
       return true;
@@ -198,7 +200,7 @@ Instruction *GCSE::EliminateCSE(Instruction *I, Instruction *Other) {
   Instruction *Ret = 0;
 
   if (BB1 == BB2) {
-    // Eliminate the second occuring instruction.  Add all uses of the second
+    // Eliminate the second occurring instruction.  Add all uses of the second
     // instruction to the worklist.
     //
     // Scan the basic block looking for the "first" instruction
@@ -239,7 +241,7 @@ Instruction *GCSE::EliminateCSE(Instruction *I, Instruction *Other) {
     //
     // Here there are no shared dominators.  Additionally, this had the habit of
     // moving computations where they were not always computed.  For example, in
-    // a cast like this:
+    // a case like this:
     //  if (c) {
     //    if (d)  ...
     //    else ... X+Y ...
@@ -247,39 +249,13 @@ Instruction *GCSE::EliminateCSE(Instruction *I, Instruction *Other) {
     //    ... X+Y ...
     //  }
     // 
-    // In thiscase, the expression would be hoisted to outside the 'if' stmt,
+    // In this case, the expression would be hoisted to outside the 'if' stmt,
     // causing the expression to be evaluated, even for the if (d) path, which
     // could cause problems, if, for example, it caused a divide by zero.  In
     // general the problem this case is trying to solve is better addressed with
     // PRE than GCSE.
     //
     return 0;
-
-#if 0
-    // Handle the most general case now.  In this case, neither I dom Other nor
-    // Other dom I.  Because we are in SSA form, we are guaranteed that the
-    // operands of the two instructions both dominate the uses, so we _know_
-    // that there must exist a block that dominates both instructions (if the
-    // operands of the instructions are globals or constants, worst case we
-    // would get the entry node of the function).  Search for this block now.
-    //
-
-    // Search up the immediate dominator chain of BB1 for the shared dominator
-    BasicBlock *SharedDom = (*ImmDominator)[BB1];
-    while (!DomSetInfo->dominates(SharedDom, BB2))
-      SharedDom = (*ImmDominator)[SharedDom];
-
-    // At this point, shared dom must dominate BOTH BB1 and BB2...
-    assert(SharedDom && DomSetInfo->dominates(SharedDom, BB1) &&
-           DomSetInfo->dominates(SharedDom, BB2) && "Dominators broken!");
-
-    // Rip 'I' out of BB1, and move it to the end of SharedDom.
-    BB1->getInstList().remove(I);
-    SharedDom->getInstList().insert(--SharedDom->end(), I);
-
-    // Eliminate 'Other' now.
-    ReplaceInstWithInst(I, Other);
-#endif
   }
 
   if (isa<LoadInst>(Ret))