Index: llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp =================================================================== --- llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -5400,7 +5400,9 @@ CollectFixupsAndInitialFormulae(); CollectLoopInvariantFixupsAndFormulae(); - assert(!Uses.empty() && "IVUsers reported at least one use"); + if (Uses.empty()) + return; + LLVM_DEBUG(dbgs() << "LSR found " << Uses.size() << " uses:\n"; print_uses(dbgs())); Index: llvm/trunk/test/CodeGen/X86/lsr-crash-empty-uses.ll =================================================================== --- llvm/trunk/test/CodeGen/X86/lsr-crash-empty-uses.ll +++ llvm/trunk/test/CodeGen/X86/lsr-crash-empty-uses.ll @@ -0,0 +1,41 @@ +; RUN: llc --start-before loop-reduce --stop-after loop-reduce %s -o - | FileCheck %s +target datalayout = "e-m:e-p:32:32-i64:64-n32-S128" +target triple = "x86_64-unknown-linux-gnu" + +define void @hoge() { +bb: + %tmp = sext i32 undef to i64 + %tmp3 = sub nsw i64 0, %tmp + br label %bb4 + +bb4: ; preds = %bb20, %bb + %tmp5 = getelementptr inbounds double, double* undef, i64 undef + %tmp6 = getelementptr inbounds double, double* %tmp5, i64 %tmp3 + br label %bb7 + +bb7: ; preds = %bb7, %bb4 + %tmp8 = phi double* [ %tmp10, %bb7 ], [ %tmp6, %bb4 ] + %tmp9 = load double, double* %tmp8 + %tmp10 = getelementptr inbounds double, double* %tmp8, i64 1 + br i1 true, label %bb11, label %bb7 + +bb11: ; preds = %bb7 + br i1 undef, label %bb20, label %bb12 + +bb12: ; preds = %bb11 + br label %bb13 + +bb13: ; preds = %bb13, %bb12 + %tmp14 = phi double* [ %tmp18, %bb13 ], [ %tmp10, %bb12 ] + %tmp15 = load double, double* %tmp14, align 8 + %tmp16 = getelementptr inbounds double, double* %tmp14, i64 1 + %tmp17 = load double, double* %tmp16, align 8 + %tmp18 = getelementptr inbounds double, double* %tmp14, i64 8 + br i1 true, label %bb19, label %bb13 + +bb19: ; preds = %bb13 + br label %bb20 + +bb20: ; preds = %bb19, %bb11 + br label %bb4 +}