For PR950:

First in a series of patches to convert SetCondInst into ICmpInst and
FCmpInst using only two opcodes and having the instructions contain their
predicate value. Nothing uses these classes yet. More patches to follow.

llvm-svn: 31867

1 files changed, 23 insertions, 0 deletions

diff --git a/llvm/lib/Analysis/ValueNumbering.cpp b/llvm/lib/Analysis/ValueNumbering.cpp
index 0224a0132fd..03b9f6b3eae 100644
--- a/llvm/lib/Analysis/ValueNumbering.cpp
+++ b/llvm/lib/Analysis/ValueNumbering.cpp
@@ -75,6 +75,7 @@ namespace {
 
     void visitCastInst(CastInst &I);
     void visitGetElementPtrInst(GetElementPtrInst &I);
+    void visitCmpInst(CmpInst &I);
 
     void handleBinaryInst(Instruction &I);
     void visitBinaryOperator(Instruction &I)     { handleBinaryInst(I); }
@@ -124,6 +125,28 @@ void BVNImpl::visitCastInst(CastInst &CI) {
       }
 }
 
+void  BVNImpl::visitCmpInst(CmpInst &CI1) {
+  Value *LHS = CI1.getOperand(0);
+  for (Value::use_iterator UI = LHS->use_begin(), UE = LHS->use_end();
+       UI != UE; ++UI)
+    if (CmpInst *CI2 = dyn_cast<CmpInst>(*UI))
+      // Check to see if this compare instruction is not CI, but same opcode,
+      // same predicate, and in the same function.
+      if (CI2 != &CI1 && CI2->getOpcode() == CI1.getOpcode() &&
+          CI2->getPredicate() == CI1.getPredicate() &&
+          CI2->getParent()->getParent() == CI1.getParent()->getParent())
+        // If the operands are the same
+        if ((CI2->getOperand(0) == CI1.getOperand(0) &&
+            CI2->getOperand(1) == CI1.getOperand(1)) ||
+            // Or the compare is commutative and the operands are reversed 
+            (CI1.isCommutative() && 
+             CI2->getOperand(0) == CI1.getOperand(1) &&
+             CI2->getOperand(1) == CI1.getOperand(0)))
+          // Then the instructiosn are identical, add to list.
+          RetVals.push_back(CI2);
+}
+
+
 
 // isIdenticalBinaryInst - Return true if the two binary instructions are
 // identical.