Add a generic expansion transform: A op (B op' C) -> (A op B) op' (A op C)
if both A op B and A op C simplify. This fires fairly often but doesn't
make that much difference. On gcc-as-one-file it removes two "and"s and
turns one branch into a select.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122399 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
index 98d6550..c4132b2 100644
--- a/lib/Transforms/InstCombine/InstCombineAddSub.cpp
+++ b/lib/Transforms/InstCombine/InstCombineAddSub.cpp
@@ -91,9 +91,10 @@
I.hasNoUnsignedWrap(), TD))
return ReplaceInstUsesWith(I, V);
- if (Instruction *NV = SimplifyByFactorizing(I)) // (A*B)+(A*C) -> A*(B+C)
- return NV;
-
+ // (A*B)+(A*C) -> A*(B+C) etc
+ if (Value *V = SimplifyUsingDistributiveLaws(I))
+ return ReplaceInstUsesWith(I, V);
+
if (Constant *RHSC = dyn_cast<Constant>(RHS)) {
if (ConstantInt *CI = dyn_cast<ConstantInt>(RHSC)) {
// X + (signbit) --> X ^ signbit
@@ -535,9 +536,10 @@
I.hasNoUnsignedWrap(), TD))
return ReplaceInstUsesWith(I, V);
- if (Instruction *NV = SimplifyByFactorizing(I)) // (A*B)-(A*C) -> A*(B-C)
- return NV;
-
+ // (A*B)-(A*C) -> A*(B-C) etc
+ if (Value *V = SimplifyUsingDistributiveLaws(I))
+ return ReplaceInstUsesWith(I, V);
+
// If this is a 'B = x-(-A)', change to B = x+A. This preserves NSW/NUW.
if (Value *V = dyn_castNegVal(Op1)) {
BinaryOperator *Res = BinaryOperator::CreateAdd(Op0, V);