commit 6609f741b9b02dd169cc2625b5100fce5336f5f9
author Benjamin Kramer <benny.kra@googlemail.com> Sun Jan 08 21:12:51 2012 +0000
committer Benjamin Kramer <benny.kra@googlemail.com> Sun Jan 08 21:12:51 2012 +0000
tree d5a05eafc90fce0accb133d6806bc2237f9a408a
parent 4882e488f794db0426b648dc0f0d5bb1046f11af

Tweak my last commit to be less conservative about uses.

We still save an instruction when just the "and" part is replaced.
Also change the code to match comments more closely.

llvm-svn: 147753

llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index 96ca40a..b4d3e62 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -745,18 +745,17 @@
   }
 
   // (X & C) == 0 & X > -1  ->  (X & (C | SignBit)) == 0
-  if (LHS->hasOneUse() && RHS->hasOneUse() &&
-      ((LHSCC == ICmpInst::ICMP_EQ && LHSCst->isZero() &&
-        RHSCC == ICmpInst::ICMP_SGT && RHSCst->isAllOnesValue()) ||
-       (RHSCC == ICmpInst::ICMP_EQ && RHSCst->isZero() &&
-        LHSCC == ICmpInst::ICMP_SGT && LHSCst->isAllOnesValue()))) {
-    BinaryOperator *BO =
-      dyn_cast<BinaryOperator>(LHSCC == ICmpInst::ICMP_EQ ? Val : Val2);
-    ConstantInt *AndCst;
-    if (BO && match(BO, m_OneUse(m_And(m_Value(), m_ConstantInt(AndCst))))) {
-      APInt New = AndCst->getValue() | APInt::getSignBit(AndCst->getBitWidth());
-      BO->setOperand(1, ConstantInt::get(AndCst->getContext(), New));
-      return BO == Val ? LHS : RHS;
+  if ((LHSCC == ICmpInst::ICMP_EQ  && LHSCst->isZero() &&
+       RHSCC == ICmpInst::ICMP_SGT && RHSCst->isAllOnesValue()) ||
+      (RHSCC == ICmpInst::ICMP_EQ  && RHSCst->isZero() &&
+       LHSCC == ICmpInst::ICMP_SGT && LHSCst->isAllOnesValue())) {
+    ICmpInst *I = LHSCC == ICmpInst::ICMP_EQ ? LHS : RHS;
+    Value *X; ConstantInt *C;
+    if (I->hasOneUse() &&
+        match(I->getOperand(0), m_OneUse(m_And(m_Value(X), m_ConstantInt(C))))){
+      APInt New = C->getValue() | APInt::getSignBit(C->getBitWidth());
+      return Builder->CreateICmpEQ(Builder->CreateAnd(X, Builder->getInt(New)),
+                                   I->getOperand(1));
     }
   }
   
@@ -1458,19 +1457,18 @@
     }
   }
 
-  // (X & C) != 0 & X < 0  ->  (X & (C | SignBit)) != 0
-  if (LHS->hasOneUse() && RHS->hasOneUse() &&
-      ((LHSCC == ICmpInst::ICMP_NE && LHSCst->isZero() &&
-        RHSCC == ICmpInst::ICMP_SLT && RHSCst->isZero()) ||
-       (RHSCC == ICmpInst::ICMP_NE && RHSCst->isZero() &&
-        LHSCC == ICmpInst::ICMP_SLT && LHSCst->isZero()))) {
-    BinaryOperator *BO =
-      dyn_cast<BinaryOperator>(LHSCC == ICmpInst::ICMP_NE ? Val : Val2);
-    ConstantInt *AndCst;
-    if (BO && match(BO, m_OneUse(m_And(m_Value(), m_ConstantInt(AndCst))))) {
-      APInt New = AndCst->getValue() | APInt::getSignBit(AndCst->getBitWidth());
-      BO->setOperand(1, ConstantInt::get(AndCst->getContext(), New));
-      return BO == Val ? LHS : RHS;
+  // (X & C) != 0 | X < 0  ->  (X & (C | SignBit)) != 0
+  if ((LHSCC == ICmpInst::ICMP_NE  && LHSCst->isZero() &&
+       RHSCC == ICmpInst::ICMP_SLT && RHSCst->isZero()) ||
+      (RHSCC == ICmpInst::ICMP_NE  && RHSCst->isZero() &&
+       LHSCC == ICmpInst::ICMP_SLT && LHSCst->isZero())) {
+    ICmpInst *I = LHSCC == ICmpInst::ICMP_NE ? LHS : RHS;
+    Value *X; ConstantInt *C;
+    if (I->hasOneUse() &&
+        match(I->getOperand(0), m_OneUse(m_And(m_Value(X), m_ConstantInt(C))))){
+      APInt New = C->getValue() | APInt::getSignBit(C->getBitWidth());
+      return Builder->CreateICmpNE(Builder->CreateAnd(X, Builder->getInt(New)),
+                                   I->getOperand(1));
     }
   }