Disable LSR retry by default.
Disabling aggressive LSR saves compilation time, and with the new
indvars behavior usually improves performance.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140590 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index 0ad9fc3..f9c18c8 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -70,12 +70,18 @@
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ValueHandle.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetLowering.h"
#include <algorithm>
using namespace llvm;
+namespace llvm {
+cl::opt<bool> EnableRetry(
+ "enable-lsr-retry", cl::Hidden, cl::desc("Enable LSR retry"));
+}
+
namespace {
/// RegSortData - This class holds data which is used to order reuse candidates.
@@ -3309,6 +3315,9 @@
skip:;
}
+ if (!EnableRetry && !AnySatisfiedReqRegs)
+ return;
+
// If none of the formulae had all of the required registers, relax the
// constraint so that we don't exclude all formulae.
if (!AnySatisfiedReqRegs) {
@@ -3332,6 +3341,10 @@
// SolveRecurse does all the work.
SolveRecurse(Solution, SolutionCost, Workspace, CurCost,
CurRegs, VisitedRegs);
+ if (Solution.empty()) {
+ DEBUG(dbgs() << "\nNo Satisfactory Solution\n");
+ return;
+ }
// Ok, we've now made all our decisions.
DEBUG(dbgs() << "\n"
@@ -3811,6 +3824,9 @@
Types.clear();
RegUses.clear();
+ if (Solution.empty())
+ return;
+
#ifndef NDEBUG
// Formulae should be legal.
for (SmallVectorImpl<LSRUse>::const_iterator I = Uses.begin(),