OptimizeShadowIV();
OptimizeLoopTermCond();
+ // If loop preparation eliminates all interesting IV users, bail.
+ if (IU.empty()) return;
+
// Start collecting data and preparing for the solver.
CollectInterestingTypesAndFactors();
CollectFixupsAndInitialFormulae();
--- /dev/null
+; RUN: opt < %s -loop-reduce -S | FileCheck %s
+;
+; Test LSR's OptimizeShadowIV. Handle a floating-point IV with a
+; nonzero initial value.
+; rdar://9786536
+
+; First, make sure LSR doesn't crash on an empty IVUsers list.
+; CHECK: @dummyIV
+; CHECK-NOT: phi
+; CHECK-NOT: sitofp
+; CHECK: br
+define void @dummyIV() nounwind {
+entry:
+ br label %loop
+
+loop:
+ %i.01 = phi i32 [ -39, %entry ], [ %inc, %loop ]
+ %conv7 = sitofp i32 %i.01 to double
+ %inc = add nsw i32 %i.01, 1
+ br i1 undef, label %loop, label %for.end
+
+for.end:
+ unreachable
+}