; RUN: opt < %s -S -basicaa -licm | FileCheck %s ; RUN: opt -aa-pipeline=basic-aa -passes='require,loop(licm)' < %s -S | FileCheck %s ; Check that we can hoist unordered loads define i32 @test1(i32* nocapture %y) nounwind uwtable ssp { entry: br label %loop loop: %i = phi i32 [ %inc, %loop ], [ 0, %entry ] %val = load atomic i32, i32* %y unordered, align 4 %inc = add nsw i32 %i, 1 %exitcond = icmp eq i32 %inc, %val br i1 %exitcond, label %end, label %loop end: ret i32 %val ; CHECK-LABEL: define i32 @test1( ; CHECK: load atomic ; CHECK-NEXT: br label %loop } ; Check that we don't sink/hoist monotonic loads ; (Strictly speaking, it's not forbidden, but it's supposed to be possible to ; use monotonic for spinlock-like constructs.) define i32 @test2(i32* nocapture %y) nounwind uwtable ssp { entry: br label %loop loop: %val = load atomic i32, i32* %y monotonic, align 4 %exitcond = icmp ne i32 %val, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %val ; CHECK-LABEL: define i32 @test2( ; CHECK: load atomic ; CHECK-NEXT: %exitcond = icmp ne ; CHECK-NEXT: br i1 %exitcond, label %end, label %loop } ; Check that we hoist unordered around monotonic. ; (The noalias shouldn't be necessary in theory, but LICM isn't quite that ; smart yet.) define i32 @test3(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp { entry: br label %loop loop: %vala = load atomic i32, i32* %y monotonic, align 4 %valb = load atomic i32, i32* %x unordered, align 4 %exitcond = icmp ne i32 %vala, %valb br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test3( ; CHECK: load atomic i32, i32* %x unordered ; CHECK-NEXT: br label %loop } ; We can sink an unordered store define i32 @test4(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp { entry: br label %loop loop: %vala = load atomic i32, i32* %y monotonic, align 4 store atomic i32 %vala, i32* %x unordered, align 4 %exitcond = icmp ne i32 %vala, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test4( ; CHECK-LABEL: loop: ; CHECK: load atomic i32, i32* %y monotonic ; CHECK-NOT: store ; CHECK-LABEL: end: ; CHECK-NEXT: %[[LCSSAPHI:.*]] = phi i32 [ %vala ; CHECK: store atomic i32 %[[LCSSAPHI]], i32* %x unordered, align 4 } ; We currently don't handle ordered atomics. define i32 @test5(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp { entry: br label %loop loop: %vala = load atomic i32, i32* %y monotonic, align 4 store atomic i32 %vala, i32* %x release, align 4 %exitcond = icmp ne i32 %vala, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test5( ; CHECK: load atomic i32, i32* %y monotonic ; CHECK-NEXT: store atomic } ; We currently don't touch volatiles define i32 @test6(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp { entry: br label %loop loop: %vala = load atomic i32, i32* %y monotonic, align 4 store volatile i32 %vala, i32* %x, align 4 %exitcond = icmp ne i32 %vala, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test6( ; CHECK: load atomic i32, i32* %y monotonic ; CHECK-NEXT: store volatile } ; We currently don't touch volatiles define i32 @test6b(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp { entry: br label %loop loop: %vala = load atomic i32, i32* %y monotonic, align 4 store atomic volatile i32 %vala, i32* %x unordered, align 4 %exitcond = icmp ne i32 %vala, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test6b( ; CHECK: load atomic i32, i32* %y monotonic ; CHECK-NEXT: store atomic volatile } ; Mixing unorder atomics and normal loads/stores is ; current unimplemented define i32 @test7(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp { entry: br label %loop loop: store i32 5, i32* %x %vala = load atomic i32, i32* %y monotonic, align 4 store atomic i32 %vala, i32* %x unordered, align 4 %exitcond = icmp ne i32 %vala, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test7( ; CHECK: store i32 5, i32* %x ; CHECK-NEXT: load atomic i32, i32* %y ; CHECK-NEXT: store atomic i32 } ; Three provably noalias locations - we can sink normal and unordered, but ; not monotonic define i32 @test7b(i32* nocapture noalias %x, i32* nocapture %y, i32* noalias nocapture %z) nounwind uwtable ssp { entry: br label %loop loop: store i32 5, i32* %x %vala = load atomic i32, i32* %y monotonic, align 4 store atomic i32 %vala, i32* %z unordered, align 4 %exitcond = icmp ne i32 %vala, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test7b( ; CHECK: load atomic i32, i32* %y monotonic ; CHECK-LABEL: end: ; CHECK: store i32 5, i32* %x ; CHECK: store atomic i32 %{{.+}}, i32* %z unordered, align 4 } define i32 @test8(i32* nocapture noalias %x, i32* nocapture %y) { entry: br label %loop loop: %vala = load atomic i32, i32* %y monotonic, align 4 store atomic i32 %vala, i32* %x unordered, align 4 fence release %exitcond = icmp ne i32 %vala, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test8( ; CHECK-LABEL: loop: ; CHECK: load atomic i32, i32* %y monotonic ; CHECK-NEXT: store atomic ; CHECK-NEXT: fence } ; Exact semantics of monotonic accesses are a bit vague in the C++ spec, ; for the moment, be conservative and don't touch them. define i32 @test9(i32* nocapture noalias %x, i32* nocapture %y) { entry: br label %loop loop: %vala = load atomic i32, i32* %y monotonic, align 4 store atomic i32 %vala, i32* %x monotonic, align 4 %exitcond = icmp ne i32 %vala, 0 br i1 %exitcond, label %end, label %loop end: ret i32 %vala ; CHECK-LABEL: define i32 @test9( ; CHECK-LABEL: loop: ; CHECK: load atomic i32, i32* %y monotonic ; CHECK-NEXT: store atomic i32 %vala, i32* %x monotonic, align 4 }