[MemDep] Fixed handling of invariant.group
Summary:
Memdep had funny bug related to invariant.groups - because it did not
invalidated cache, in some very rare cases it was possible to show memory
dependence of the instruction that was deleted, but because other
instruction took it's place it resulted in call to vtable!
Thanks @amharc for repro!.
Reviewers: dberlin, kuhar, amharc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45320
Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 332781
diff --git a/llvm/test/Analysis/MemoryDependenceAnalysis/invariant.group-bug.ll b/llvm/test/Analysis/MemoryDependenceAnalysis/invariant.group-bug.ll
new file mode 100644
index 0000000..00ed8d6
--- /dev/null
+++ b/llvm/test/Analysis/MemoryDependenceAnalysis/invariant.group-bug.ll
@@ -0,0 +1,111 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -gvn -S < %s | FileCheck %s
+
+; Memdep had funny bug related to invariant.groups - because it did not
+; invalidated cache, in some very rare cases it was possible to show memory
+; dependence of the instruction that was deleted, but because other instruction
+; took it's place it resulted in call to vtable! Removing any of the branch
+; hides the bug.
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-grtev4-linux-gnu"
+
+%0 = type { i32 (...)**, %1 }
+%1 = type { %2 }
+%2 = type { %3 }
+%3 = type { %4, i64, %5 }
+%4 = type { i8* }
+%5 = type { i64, [8 x i8] }
+
+define void @fail(i1* noalias sret, %0*, %1*, i8*) local_unnamed_addr #0 {
+; CHECK-LABEL: @fail(
+; CHECK-NEXT: [[TMP5:%.*]] = bitcast %0* [[TMP1:%.*]] to i64 (%0*)***
+; CHECK-NEXT: [[TMP6:%.*]] = load i64 (%0*)**, i64 (%0*)*** [[TMP5]], align 8, !invariant.group !6
+; CHECK-NEXT: [[TMP7:%.*]] = getelementptr inbounds i64 (%0*)*, i64 (%0*)** [[TMP6]], i64 6
+; CHECK-NEXT: [[TMP8:%.*]] = load i64 (%0*)*, i64 (%0*)** [[TMP7]], align 8, !invariant.load !6
+; CHECK-NEXT: [[TMP9:%.*]] = tail call i64 [[TMP8]](%0* [[TMP1]]) #1
+; CHECK-NEXT: [[TMP10:%.*]] = getelementptr inbounds [[TMP1]], %1* [[TMP2:%.*]], i64 0, i32 0, i32 0, i32 0, i32 0
+; CHECK-NEXT: [[TMP11:%.*]] = load i8*, i8** [[TMP10]], align 8
+; CHECK-NEXT: store i8 0, i8* [[TMP11]], align 1
+; CHECK-NEXT: [[TMP12:%.*]] = bitcast i64 (%0*)** [[TMP6]] to i64 (%0*, i8*, i64)**
+; CHECK-NEXT: br i1 undef
+; CHECK: [[TMP14:%.*]] = bitcast %0* [[TMP1]] to i64 (%0*, i8*, i64)***
+; CHECK-NEXT: [[DOTPHI_TRANS_INSERT:%.*]] = getelementptr inbounds i64 (%0*, i8*, i64)*, i64 (%0*, i8*, i64)** [[TMP12]], i64 22
+; CHECK-NEXT: [[DOTPRE:%.*]] = load i64 (%0*, i8*, i64)*, i64 (%0*, i8*, i64)** [[DOTPHI_TRANS_INSERT]], align 8, !invariant.load !6
+; CHECK-NEXT: br label [[TMP15:%.*]]
+; CHECK: [[TMP16:%.*]] = call i64 [[DOTPRE]](%0* nonnull [[TMP1]], i8* null, i64 0) #1
+
+ %5 = bitcast %0* %1 to i64 (%0*)***
+ %6 = load i64 (%0*)**, i64 (%0*)*** %5, align 8, !invariant.group !6
+ %7 = getelementptr inbounds i64 (%0*)*, i64 (%0*)** %6, i64 6
+ %8 = load i64 (%0*)*, i64 (%0*)** %7, align 8, !invariant.load !6
+ %9 = tail call i64 %8(%0* %1) #1
+ %10 = getelementptr inbounds %1, %1* %2, i64 0, i32 0, i32 0, i32 0, i32 0
+ %11 = load i8*, i8** %10, align 8
+ store i8 0, i8* %11, align 1
+ br i1 undef, label %12, label %31
+
+; <label>:12: ; preds = %4
+ %13 = bitcast %0* %1 to i64 (%0*, i8*, i64)***
+ br label %14
+
+; <label>:14: ; preds = %30, %12
+ %15 = load i64 (%0*, i8*, i64)**, i64 (%0*, i8*, i64)*** %13, align 8, !invariant.group !6
+ %16 = getelementptr inbounds i64 (%0*, i8*, i64)*, i64 (%0*, i8*, i64)** %15, i64 22
+ %17 = load i64 (%0*, i8*, i64)*, i64 (%0*, i8*, i64)** %16, align 8, !invariant.load !6
+ %18 = call i64 %17(%0* nonnull %1, i8* null, i64 0) #1
+ br i1 undef, label %30, label %19
+
+; <label>:19: ; preds = %14
+ br i1 undef, label %20, label %23
+
+; <label>:20: ; preds = %19
+ br label %21
+
+; <label>:21: ; preds = %20
+ br label %22
+
+; <label>:22: ; preds = %21
+ br label %30
+
+; <label>:23: ; preds = %19
+ br label %24
+
+; <label>:24: ; preds = %23
+ br label %25
+
+; <label>:25: ; preds = %24
+ br label %26
+
+; <label>:26: ; preds = %25
+ br i1 undef, label %27, label %28
+
+; <label>:27: ; preds = %26
+ br label %30
+
+; <label>:28: ; preds = %26
+ br label %29
+
+; <label>:29: ; preds = %28
+ br label %30
+
+; <label>:30: ; preds = %29, %27, %22, %14
+ br i1 undef, label %14, label %31
+
+; <label>:31: ; preds = %30, %4
+ ret void
+}
+
+attributes #0 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+popcnt,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+popcnt,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!llvm.linker.options = !{}
+!llvm.module.flags = !{!0, !1, !3, !4, !5}
+
+!0 = !{i32 1, !"StrictVTablePointers", i32 1}
+!1 = !{i32 3, !"StrictVTablePointersRequirement", !2}
+!2 = !{!"StrictVTablePointers", i32 1}
+!3 = !{i32 1, !"wchar_size", i32 4}
+!4 = !{i32 7, !"PIC Level", i32 2}
+!5 = !{i32 7, !"PIE Level", i32 2}
+!6 = !{}