From d97136c182a5832b61b036c4537f38ac603345ef Mon Sep 17 00:00:00 2001 From: Nikolai Bozhenov Date: Thu, 10 Aug 2017 11:24:57 +0000 Subject: [ValueTracking] Enabling ValueTracking patch by default (recommit). Part 2. The original patch was an improvement to IR ValueTracking on non-negative integers. It has been checked in to trunk (D18777, r284022). But was disabled by default due to performance regressions. Perf impact has improved. The patch would be enabled by default. Reviewers: reames, hfinkel Differential Revision: https://reviews.llvm.org/D34101 Patch by: Olga Chupina llvm-svn: 310583 --- llvm/lib/Analysis/ValueTracking.cpp | 9 --------- 1 file changed, 9 deletions(-) (limited to 'llvm/lib/Analysis/ValueTracking.cpp') diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp index b81bf9ec9d1..279d880904e 100644 --- a/llvm/lib/Analysis/ValueTracking.cpp +++ b/llvm/lib/Analysis/ValueTracking.cpp @@ -54,12 +54,6 @@ const unsigned MaxDepth = 6; static cl::opt DomConditionsMaxUses("dom-conditions-max-uses", cl::Hidden, cl::init(20)); -// This optimization is known to cause performance regressions is some cases, -// keep it under a temporary flag for now. -static cl::opt -DontImproveNonNegativePhiBits("dont-improve-non-negative-phi-bits", - cl::Hidden, cl::init(true)); - /// Returns the bitwidth of the given scalar or pointer type. For vector types, /// returns the element type's bitwidth. static unsigned getBitWidth(Type *Ty, const DataLayout &DL) { @@ -1258,9 +1252,6 @@ static void computeKnownBitsFromOperator(const Operator *I, KnownBits &Known, Known.Zero.setLowBits(std::min(Known2.countMinTrailingZeros(), Known3.countMinTrailingZeros())); - if (DontImproveNonNegativePhiBits) - break; - auto *OverflowOp = dyn_cast(LU); if (OverflowOp && OverflowOp->hasNoSignedWrap()) { // If initial value of recurrence is nonnegative, and we are adding -- cgit v1.2.3