diff options
| -rw-r--r-- | lib/Analysis/ScalarEvolution.cpp | 12 | ||||
| -rw-r--r-- | test/Analysis/ScalarEvolution/max-trip-count.ll | 28 |
2 files changed, 4 insertions, 36 deletions
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp index a630c7e710..ea45e9d72c 100644 --- a/lib/Analysis/ScalarEvolution.cpp +++ b/lib/Analysis/ScalarEvolution.cpp @@ -5119,7 +5119,7 @@ SolveQuadraticEquation(const SCEVAddRecExpr *AddRec, ScalarEvolution &SE) { // Compute the two solutions for the quadratic formula. // The divisions must be performed as signed divisions. APInt NegB(-B); - APInt TwoA(A << 1); + APInt TwoA( A << 1 ); if (TwoA.isMinValue()) { const SCEV *CNC = SE.getCouldNotCompute(); return std::make_pair(CNC, CNC); @@ -5134,7 +5134,7 @@ SolveQuadraticEquation(const SCEVAddRecExpr *AddRec, ScalarEvolution &SE) { return std::make_pair(SE.getConstant(Solution1), SE.getConstant(Solution2)); - } // end APIntOps namespace + } // end APIntOps namespace } /// HowFarToZero - Return the number of times a backedge comparing the specified @@ -5228,12 +5228,8 @@ ScalarEvolution::HowFarToZero(const SCEV *V, const Loop *L) { // Handle unitary steps, which cannot wraparound. // 1*N = -Start; -1*N = Start (mod 2^BW), so: // N = Distance (as unsigned) - if (StepC->getValue()->equalsInt(1) || StepC->getValue()->isAllOnesValue()) { - ConstantRange CR = getUnsignedRange(Start); - const SCEV *MaxBECount = getConstant(CountDown ? CR.getUnsignedMax() - : ~CR.getUnsignedMin()); - return ExitLimit(Distance, MaxBECount); - } + if (StepC->getValue()->equalsInt(1) || StepC->getValue()->isAllOnesValue()) + return Distance; // If the recurrence is known not to wraparound, unsigned divide computes the // back edge count. We know that the value will either become zero (and thus diff --git a/test/Analysis/ScalarEvolution/max-trip-count.ll b/test/Analysis/ScalarEvolution/max-trip-count.ll index 0cdbdf57a6..843fb07308 100644 --- a/test/Analysis/ScalarEvolution/max-trip-count.ll +++ b/test/Analysis/ScalarEvolution/max-trip-count.ll @@ -70,31 +70,3 @@ for.end: ; preds = %for.body, %for.cond } declare i32 @printf(i8*, ...) - -define void @test(i8* %a, i32 %n) nounwind { -entry: - %cmp1 = icmp sgt i32 %n, 0 - br i1 %cmp1, label %for.body.lr.ph, label %for.end - -for.body.lr.ph: ; preds = %entry - %tmp = zext i32 %n to i64 - br label %for.body - -for.body: ; preds = %for.body, %for.body.lr.ph - %indvar = phi i64 [ %indvar.next, %for.body ], [ 0, %for.body.lr.ph ] - %arrayidx = getelementptr i8* %a, i64 %indvar - store i8 0, i8* %arrayidx, align 1 - %indvar.next = add i64 %indvar, 1 - %exitcond = icmp ne i64 %indvar.next, %tmp - br i1 %exitcond, label %for.body, label %for.cond.for.end_crit_edge - -for.cond.for.end_crit_edge: ; preds = %for.body - br label %for.end - -for.end: ; preds = %for.cond.for.end_crit_edge, %entry - ret void -} - -; CHECK: Determining loop execution counts for: @test -; CHECK-NEXT: backedge-taken count is -; CHECK-NEXT: max backedge-taken count is -1 |