Remove redunant optimizations from InstCombine, instead call the appr…

…opriate functions from SimplifyInstruction

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169941 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/InstCombine/InstCombineAddSub.cpp

@@ -351,18 +351,8 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
   bool Changed = SimplifyAssociativeOrCommutative(I);
   Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
 
-  if (Constant *RHSC = dyn_cast<Constant>(RHS)) {
-    // X + 0 --> X
-    if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHSC)) {
-      if (CFP->isExactlyValue(ConstantFP::getNegativeZero
-                              (I.getType())->getValueAPF()))
-        return ReplaceInstUsesWith(I, LHS);
-    }
-
-    if (isa<PHINode>(LHS))
-      if (Instruction *NV = FoldOpIntoPhi(I))
-        return NV;
-  }
+  if (Value *V = SimplifyFAddInst(LHS, RHS, I.getFastMathFlags(), TD))
+    return ReplaceInstUsesWith(I, V);
 
   // -A + B  -->  B - A
   // -A + -B  -->  -(A + B)
@@ -374,11 +364,6 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
     if (Value *V = dyn_castFNegVal(RHS))
       return BinaryOperator::CreateFSub(LHS, V);
 
-  // Check for X+0.0.  Simplify it to X if we know X is not -0.0.
-  if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHS))
-    if (CFP->getValueAPF().isPosZero() && CannotBeNegativeZero(LHS))
-      return ReplaceInstUsesWith(I, LHS);
-
   // Check for (fadd double (sitofp x), y), see if we can merge this into an
   // integer add followed by a promotion.
   if (SIToFPInst *LHSConv = dyn_cast<SIToFPInst>(LHS)) {
@@ -653,6 +638,9 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
 Instruction *InstCombiner::visitFSub(BinaryOperator &I) {
   Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
 
+  if (Value *V = SimplifyFSubInst(Op0, Op1, I.getFastMathFlags(), TD))
+    return ReplaceInstUsesWith(I, V);
+
   // If this is a 'B = x-(-A)', change to B = x+A...
   if (Value *V = dyn_castFNegVal(Op1))
     return BinaryOperator::CreateFAdd(Op0, V);

lib/Transforms/InstCombine/InstCombineMulDivRem.cpp

@@ -296,20 +296,11 @@ Instruction *InstCombiner::visitFMul(BinaryOperator &I) {
   bool Changed = SimplifyAssociativeOrCommutative(I);
   Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
 
-  // Simplify mul instructions with a constant RHS.
-  if (Constant *Op1C = dyn_cast<Constant>(Op1)) {
-    if (ConstantFP *Op1F = dyn_cast<ConstantFP>(Op1C)) {
-      // "In IEEE floating point, x*1 is not equivalent to x for nans.  However,
-      // ANSI says we can drop signals, so we can do this anyway." (from GCC)
-      if (Op1F->isExactlyValue(1.0))
-        return ReplaceInstUsesWith(I, Op0);  // Eliminate 'fmul double %X, 1.0'
-    } else if (ConstantDataVector *Op1V = dyn_cast<ConstantDataVector>(Op1C)) {
-      // As above, vector X*splat(1.0) -> X in all defined cases.
-      if (ConstantFP *F = dyn_cast_or_null<ConstantFP>(Op1V->getSplatValue()))
-        if (F->isExactlyValue(1.0))
-          return ReplaceInstUsesWith(I, Op0);
-    }
+  if (Value *V = SimplifyFMulInst(Op0, Op1, I.getFastMathFlags(), TD))
+    return ReplaceInstUsesWith(I, V);
 
+  // Simplify mul instructions with a constant RHS.
+  if (isa<Constant>(Op1)) {
     // Try to fold constant mul into select arguments.
     if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
       if (Instruction *R = FoldOpIntoSelect(I, SI))