diff options
Diffstat (limited to 'llvm')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp | 2 | ||||
| -rw-r--r-- | llvm/test/Transforms/TailCallElim/dup_tail.ll | 23 |
2 files changed, 25 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp b/llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp index 61f230804f5..50d4cc33171 100644 --- a/llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp +++ b/llvm/lib/Transforms/Scalar/TailRecursionElimination.cpp @@ -72,6 +72,7 @@ using namespace llvm; STATISTIC(NumEliminated, "Number of tail calls removed"); +STATISTIC(NumRetDuped, "Number of return duplicated"); STATISTIC(NumAccumAdded, "Number of accumulators introduced"); namespace { @@ -606,6 +607,7 @@ bool TailCallElim::FoldReturnAndProcessPred(BasicBlock *BB, EliminateRecursiveTailCall(CI, FoldReturnIntoUncondBranch(Ret, BB, Pred), OldEntry, TailCallsAreMarkedTail, ArgumentPHIs, CannotTailCallElimCallsMarkedTail); + ++NumRetDuped; Change = true; } } diff --git a/llvm/test/Transforms/TailCallElim/dup_tail.ll b/llvm/test/Transforms/TailCallElim/dup_tail.ll new file mode 100644 index 00000000000..93638804f92 --- /dev/null +++ b/llvm/test/Transforms/TailCallElim/dup_tail.ll @@ -0,0 +1,23 @@ +; Duplicate the return into if.end to enable TCE. +; RUN: opt %s -tailcallelim -stats -disable-output |& grep {Number of return duplicated} + +define i32 @fib(i32 %n) nounwind ssp { +entry: + %cmp = icmp slt i32 %n, 2 + br i1 %cmp, label %if.then, label %if.end + +if.then: ; preds = %entry + br label %return + +if.end: ; preds = %entry + %sub = add nsw i32 %n, -2 + %call = call i32 @fib(i32 %sub) + %sub3 = add nsw i32 %n, -1 + %call4 = call i32 @fib(i32 %sub3) + %add = add nsw i32 %call, %call4 + br label %return + +return: ; preds = %if.end, %if.then + %retval.0 = phi i32 [ 1, %if.then ], [ %add, %if.end ] + ret i32 %retval.0 +} |
