Index: lib/Transforms/Scalar/LoopSimplifyCFG.cpp =================================================================== --- lib/Transforms/Scalar/LoopSimplifyCFG.cpp +++ lib/Transforms/Scalar/LoopSimplifyCFG.cpp @@ -37,7 +37,8 @@ #define DEBUG_TYPE "loop-simplifycfg" -static bool simplifyLoopCFG(Loop &L, DominatorTree &DT, LoopInfo &LI) { +static bool simplifyLoopCFG(Loop &L, DominatorTree &DT, LoopInfo &LI, + ScalarEvolution &SE) { bool Changed = false; // Copy blocks into a temporary array to avoid iterator invalidation issues // as we remove them. @@ -59,6 +60,8 @@ L.moveToHeader(Succ); LI.removeBlock(Pred); MergeBasicBlockIntoOnlyPred(Succ, &DT); + + SE.forgetLoop(&L); Changed = true; } @@ -68,7 +71,7 @@ PreservedAnalyses LoopSimplifyCFGPass::run(Loop &L, LoopAnalysisManager &AM, LoopStandardAnalysisResults &AR, LPMUpdater &) { - if (!simplifyLoopCFG(L, AR.DT, AR.LI)) + if (!simplifyLoopCFG(L, AR.DT, AR.LI, AR.SE)) return PreservedAnalyses::all(); return getLoopPassPreservedAnalyses(); @@ -88,7 +91,8 @@ DominatorTree &DT = getAnalysis().getDomTree(); LoopInfo &LI = getAnalysis().getLoopInfo(); - return simplifyLoopCFG(*L, DT, LI); + ScalarEvolution &SE = getAnalysis().getSE(); + return simplifyLoopCFG(*L, DT, LI, SE); } void getAnalysisUsage(AnalysisUsage &AU) const override { Index: test/Transforms/LoopSimplifyCFG/scev.ll =================================================================== --- /dev/null +++ test/Transforms/LoopSimplifyCFG/scev.ll @@ -0,0 +1,57 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt -S -loop-simplifycfg -verify-scev < %s | FileCheck %s + +; Verify that the scev information is still valid. Verification should not fail + +define void @t_run_test() { +; CHECK-LABEL: @t_run_test( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP_PH:%.*]] +; CHECK: loop.ph: +; CHECK-NEXT: br label [[LOOP_BODY:%.*]] +; CHECK: loop.body: +; CHECK-NEXT: [[IV:%.*]] = phi i32 [ 0, [[LOOP_PH]] ], [ [[INC:%.*]], [[LOOP_BODY]] ] +; CHECK-NEXT: [[INC]] = add i32 [[IV]], 1 +; CHECK-NEXT: [[CMP:%.*]] = icmp ult i32 [[INC]], 10 +; CHECK-NEXT: br i1 [[CMP]], label [[LOOP_BODY]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: br label [[LOOP_BODY2:%.*]] +; CHECK: loop.body2: +; CHECK-NEXT: [[IV2:%.*]] = phi i32 [ 0, [[EXIT]] ], [ [[INC2:%.*]], [[LOOP_BODY2]] ] +; CHECK-NEXT: [[INC2]] = add i32 [[IV2]], 1 +; CHECK-NEXT: [[CMP2:%.*]] = icmp ult i32 [[INC2]], 10 +; CHECK-NEXT: br i1 [[CMP2]], label [[LOOP_BODY2]], label [[EXIT2:%.*]] +; CHECK: exit2: +; CHECK-NEXT: ret void +; +entry: + br label %loop.ph + +loop.ph: + br label %loop.header + +loop.header: + %iv = phi i32 [0, %loop.ph], [%inc, %loop.body] + br label %loop.body1 + +loop.body1: + br label %loop.body + +loop.body: + %inc = add i32 %iv, 1 + %cmp = icmp ult i32 %inc, 10 + br i1 %cmp, label %loop.header, label %exit + +exit: + br label %loop.body2 + +loop.body2: + %iv2 = phi i32 [0, %exit], [%inc2, %loop.body2] + %inc2 = add i32 %iv2, 1 + %cmp2 = icmp ult i32 %inc2, 10 + br i1 %cmp2, label %loop.body2, label %exit2 + +exit2: + ret void +} +