; This test checks that nested loops are revisited in various scenarios when ; unrolling. Note that if we ever start doing outer loop peeling a test case ; for that should be added here that will look essentially like a hybrid of the ; current two cases. ; ; RUN: opt < %s -disable-output -debug-pass-manager 2>&1 \ ; RUN: -passes='require<opt-remark-emit>,loop(loop-unroll-full)' \ ; RUN: | FileCheck %s ; ; Also run in a special mode that visits children. ; RUN: opt < %s -disable-output -debug-pass-manager -unroll-revisit-child-loops 2>&1 \ ; RUN: -passes='require<opt-remark-emit>,loop(loop-unroll-full)' \ ; RUN: | FileCheck %s --check-prefixes=CHECK,CHECK-CHILDREN ; Basic test is fully unrolled and we revisit the post-unroll new sibling ; loops, including the ones that used to be child loops. define void @full_unroll(i1* %ptr) { ; CHECK-LABEL: OptimizationRemarkEmitterAnalysis on full_unroll ; CHECK-NOT: LoopFullUnrollPass entry: br label %l0 l0: %cond.0 = load volatile i1, i1* %ptr br i1 %cond.0, label %l0.0.ph, label %exit l0.0.ph: br label %l0.0 l0.0: %iv = phi i32 [ %iv.next, %l0.0.latch ], [ 0, %l0.0.ph ] %iv.next = add i32 %iv, 1 br label %l0.0.0.ph l0.0.0.ph: br label %l0.0.0 l0.0.0: %cond.0.0.0 = load volatile i1, i1* %ptr br i1 %cond.0.0.0, label %l0.0.0, label %l0.0.1.ph ; CHECK: LoopFullUnrollPass on Loop at depth 3 containing: %l0.0.0<header> ; CHECK-NOT: LoopFullUnrollPass l0.0.1.ph: br label %l0.0.1 l0.0.1: %cond.0.0.1 = load volatile i1, i1* %ptr br i1 %cond.0.0.1, label %l0.0.1, label %l0.0.latch ; CHECK: LoopFullUnrollPass on Loop at depth 3 containing: %l0.0.1<header> ; CHECK-NOT: LoopFullUnrollPass l0.0.latch: %cmp = icmp slt i32 %iv.next, 2 br i1 %cmp, label %l0.0, label %l0.latch ; CHECK: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0 ; CHECK-NOT: LoopFullUnrollPass ; ; Unrolling occurs, so we visit what were the inner loops twice over. First we ; visit their clones, and then we visit the original loops re-parented. ; CHECK: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0.1.1<header> ; CHECK-NOT: LoopFullUnrollPass ; CHECK: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0.0.1<header> ; CHECK-NOT: LoopFullUnrollPass ; CHECK: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0.1<header> ; CHECK-NOT: LoopFullUnrollPass ; CHECK: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0.0<header> ; CHECK-NOT: LoopFullUnrollPass l0.latch: br label %l0 ; CHECK: LoopFullUnrollPass on Loop at depth 1 containing: %l0<header> ; CHECK-NOT: LoopFullUnrollPass exit: ret void } ; Now we test forced runtime partial unrolling with metadata. Here we end up ; duplicating child loops without changing their structure and so they aren't by ; default visited, but will be visited with a special parameter. define void @partial_unroll(i32 %count, i1* %ptr) { ; CHECK-LABEL: OptimizationRemarkEmitterAnalysis on partial_unroll ; CHECK-NOT: LoopFullUnrollPass entry: br label %l0 l0: %cond.0 = load volatile i1, i1* %ptr br i1 %cond.0, label %l0.0.ph, label %exit l0.0.ph: br label %l0.0 l0.0: %iv = phi i32 [ %iv.next, %l0.0.latch ], [ 0, %l0.0.ph ] %iv.next = add i32 %iv, 1 br label %l0.0.0.ph l0.0.0.ph: br label %l0.0.0 l0.0.0: %cond.0.0.0 = load volatile i1, i1* %ptr br i1 %cond.0.0.0, label %l0.0.0, label %l0.0.1.ph ; CHECK: LoopFullUnrollPass on Loop at depth 3 containing: %l0.0.0<header> ; CHECK-NOT: LoopFullUnrollPass l0.0.1.ph: br label %l0.0.1 l0.0.1: %cond.0.0.1 = load volatile i1, i1* %ptr br i1 %cond.0.0.1, label %l0.0.1, label %l0.0.latch ; CHECK: LoopFullUnrollPass on Loop at depth 3 containing: %l0.0.1<header> ; CHECK-NOT: LoopFullUnrollPass l0.0.latch: %cmp = icmp slt i32 %iv.next, %count br i1 %cmp, label %l0.0, label %l0.latch, !llvm.loop !1 ; CHECK: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0 ; CHECK-NOT: LoopFullUnrollPass ; ; Partial unrolling occurs which introduces both new child loops and new sibling ; loops. We only visit the child loops in a special mode, not by default. ; CHECK-CHILDREN: LoopFullUnrollPass on Loop at depth 3 containing: %l0.0.0<header> ; CHECK-CHILDREN-NOT: LoopFullUnrollPass ; CHECK-CHILDREN: LoopFullUnrollPass on Loop at depth 3 containing: %l0.0.1<header> ; CHECK-CHILDREN-NOT: LoopFullUnrollPass ; CHECK-CHILDREN: LoopFullUnrollPass on Loop at depth 3 containing: %l0.0.0.1<header> ; CHECK-CHILDREN-NOT: LoopFullUnrollPass ; CHECK-CHILDREN: LoopFullUnrollPass on Loop at depth 3 containing: %l0.0.1.1<header> ; CHECK-CHILDREN-NOT: LoopFullUnrollPass ; ; When we revisit children, we also revisit the current loop. ; CHECK-CHILDREN: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0<header> ; CHECK-CHILDREN-NOT: LoopFullUnrollPass ; ; Revisit the children of the outer loop that are part of the epilogue. ; ; CHECK: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0.1.epil<header> ; CHECK-NOT: LoopFullUnrollPass ; CHECK: LoopFullUnrollPass on Loop at depth 2 containing: %l0.0.0.epil<header> ; CHECK-NOT: LoopFullUnrollPass l0.latch: br label %l0 ; CHECK: LoopFullUnrollPass on Loop at depth 1 containing: %l0<header> ; CHECK-NOT: LoopFullUnrollPass exit: ret void } !1 = !{!1, !2} !2 = !{!"llvm.loop.unroll.count", i32 2}