[LoopUnrollRuntime] Clean up a predicate.
Clean up a predicate I added in r229731, fix the relevant comment and
add a test case. The earlier version is confusing to read and was also
buggy (probably not a coincidence) till Alexey fixed it in r233881.
llvm-svn: 234701
diff --git a/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp b/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp
index 46570a1..c8d4782 100644
--- a/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp
+++ b/llvm/lib/Transforms/Utils/LoopUnrollRuntime.cpp
@@ -318,9 +318,8 @@
return false;
// This constraint lets us deal with an overflowing trip count easily; see the
- // comment on ModVal below. This check is equivalent to `Log2(Count) <
- // BEWidth`.
- if (BEWidth < 64 && static_cast<uint64_t>(Count) > (1ULL << BEWidth))
+ // comment on ModVal below.
+ if (Log2_32(Count) > BEWidth)
return false;
// If this loop is nested, then the loop unroller changes the code in