[llvm] [InstCombine] Make `takeLog2` usable throughout InstCombine; NFC (PR #122498)

[via llvm-commits]

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@@ -531,19 +528,13 @@ Instruction *InstCombinerImpl::visitMul(BinaryOperator &I) {
   //        (shl Op1, Log2(Op0))
   //    if Log2(Op1) folds away ->
   //        (shl Op0, Log2(Op1))
-  if (takeLog2(Builder, Op0, /*Depth*/ 0, /*AssumeNonZero*/ false,
-               /*DoFold*/ false)) {
-    Value *Res = takeLog2(Builder, Op0, /*Depth*/ 0, /*AssumeNonZero*/ false,
-                          /*DoFold*/ true);
+  if (Value *Res = tryGetLog2(Op0, /*AssumeNonZero=*/false)) {
     BinaryOperator *Shl = BinaryOperator::CreateShl(Op1, Res);
     // We can only propegate nuw flag.
     Shl->setHasNoUnsignedWrap(HasNUW);
     return Shl;
   }
-  if (takeLog2(Builder, Op1, /*Depth*/ 0, /*AssumeNonZero*/ false,
-               /*DoFold*/ false)) {
-    Value *Res = takeLog2(Builder, Op1, /*Depth*/ 0, /*AssumeNonZero*/ false,
-                          /*DoFold*/ true);
+  if (Value *Res = tryGetLog2(Op0, /*AssumeNonZero=*/false)) {
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goldsteinn wrote:

Mistake here.

https://github.com/llvm/llvm-project/pull/122498