From 88af7d00fc2584217465f07e1f0cc5bbf63d6592 Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Tue, 28 Sep 2010 18:32:13 +0000 Subject: Part one of switching to using a more sane heuristic for determining if-conversion profitability. Rather than having arbitrary cutoffs, actually try to cost model the conversion. For now, the constants are tuned to more or less match our existing behavior, but these will be changed to reflect realistic values as this work proceeds. llvm-svn: 114973 --- llvm/lib/CodeGen/IfConversion.cpp | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'llvm/lib/CodeGen/IfConversion.cpp') diff --git a/llvm/lib/CodeGen/IfConversion.cpp b/llvm/lib/CodeGen/IfConversion.cpp index d73cd538f32..c9c56dd86d2 100644 --- a/llvm/lib/CodeGen/IfConversion.cpp +++ b/llvm/lib/CodeGen/IfConversion.cpp @@ -191,13 +191,13 @@ namespace { void MergeBlocks(BBInfo &ToBBI, BBInfo &FromBBI, bool AddEdges = true); bool MeetIfcvtSizeLimit(MachineBasicBlock &BB, unsigned Size) const { - return Size > 0 && TII->isProfitableToIfCvt(BB, Size); + return Size > 0 && TII->isProfitableToIfCvt(BB, Size, 0.5); } bool MeetIfcvtSizeLimit(MachineBasicBlock &TBB, unsigned TSize, MachineBasicBlock &FBB, unsigned FSize) const { return TSize > 0 && FSize > 0 && - TII->isProfitableToIfCvt(TBB, TSize, FBB, FSize); + TII->isProfitableToIfCvt(TBB, TSize, FBB, FSize, 0.5); } // blockAlwaysFallThrough - Block ends without a terminator. @@ -444,7 +444,7 @@ bool IfConverter::ValidSimple(BBInfo &TrueBBI, unsigned &Dups) const { if (TrueBBI.BB->pred_size() > 1) { if (TrueBBI.CannotBeCopied || - !TII->isProfitableToDupForIfCvt(*TrueBBI.BB, TrueBBI.NonPredSize)) + !TII->isProfitableToDupForIfCvt(*TrueBBI.BB, TrueBBI.NonPredSize, 0.5)) return false; Dups = TrueBBI.NonPredSize; } @@ -481,7 +481,7 @@ bool IfConverter::ValidTriangle(BBInfo &TrueBBI, BBInfo &FalseBBI, ++Size; } } - if (!TII->isProfitableToDupForIfCvt(*TrueBBI.BB, Size)) + if (!TII->isProfitableToDupForIfCvt(*TrueBBI.BB, Size, 0.5)) return false; Dups = Size; } -- cgit v1.2.3