[Attributor] Simplify comparison against constant null pointer

[jdoerfert]

Summary

Comparison against null is a common pattern that usually is followed by
error handling code and the likes. We now use AANonNull to simplify
these comparisons optimistically in order to make more code dead early
on.

[kuter]

I think the logic is correct, other people might want to check too.
Maybe we want to add more comments, it doesn't seem obvious what's happening here.

[okura]

I think the logic is correct too and we need comments for this.
IMHO, putting the conditional into helper function would improve readability.

[uenoku]

Great, LGTM :)

[jdoerfert]

FWIW, I moved the logic in a helper and added comments. Feel free to let me know if there is anything else :)

llvm/lib/Transforms/IPO/AttributorAttributes.cpp

void initialize(Attributor &A) override {
     // AAValueSimplifyImpl::initialize(A);
     Value &V = getAnchorValue();
 
     // TODO: add other stuffs
     if (isa<Constant>(V))
       indicatePessimisticFixpoint();
   }
 
+  /// Check if \p ICmp is an equality comparison (==/!=) with at least one
+  /// nullptr. If so, try to simplify it using AANonNull on the other operand.
+  /// Return true if successful, in that case SimplifiedAssociatedValue will be
+  /// updated and \p Changed is set appropriately.
+  bool checkForNullPtrCompare(Attributor &A, ICmpInst *ICmp,
+                              ChangeStatus &Changed) {
+    if (!ICmp)
+      return false;
+    if (!ICmp->isEquality())
+      return false;
+
+    // This is a comparison with == or !-. We check for nullptr now.
+    bool Op0IsNull = isa<ConstantPointerNull>(ICmp->getOperand(0));
+    bool Op1IsNull = isa<ConstantPointerNull>(ICmp->getOperand(1));
+    if (!Op0IsNull && !Op1IsNull)
+      return false;
+
+    LLVMContext &Ctx = ICmp->getContext();
+    // Check for `nullptr ==/!= nullptr` first:
+    if (Op0IsNull && Op1IsNull) {
+      Value *NewVal = ConstantInt::get(
+          Type::getInt1Ty(Ctx), ICmp->getPredicate() == CmpInst::ICMP_EQ);
+      SimplifiedAssociatedValue = NewVal;
+      indicateOptimisticFixpoint();
+      assert(!SimplifiedAssociatedValue.hasValue() &&
+             "Did not expect non-fixed value for constant comparison");
+      Changed = ChangeStatus::CHANGED;
+      return true;
+    }
+
+    // Left is the nullptr ==/!= non-nullptr case. We'll use AANonNull on the
+    // non-nullptr operand and if we assume it's non-null we can conclude the
+    // result of the comparison.
+    assert((Op0IsNull || Op1IsNull) &&
+           "Expected nullptr versus non-nullptr comparison at this point");
+
+    // The index is the operand that we assume is not null.
+    unsigned PtrIdx = Op0IsNull;
+    auto &PtrNonNullAA = A.getAAFor<AANonNull>(
+        *this, IRPosition::value(*ICmp->getOperand(PtrIdx)));
+    if (!PtrNonNullAA.isAssumedNonNull())
+      return false;
+
+    // The new value depends on the predicate, true for != and false for ==.
+    Value *NewVal = ConstantInt::get(Type::getInt1Ty(Ctx),
+                                     ICmp->getPredicate() == CmpInst::ICMP_NE);
+
+    assert((!SimplifiedAssociatedValue.hasValue() ||
+            SimplifiedAssociatedValue == NewVal) &&
+           "Did not expect to change value for zero-comparison");
+
+    bool HasValueBefore = SimplifiedAssociatedValue.hasValue();
+    SimplifiedAssociatedValue = NewVal;
+
+    if (PtrNonNullAA.isKnownNonNull())
+      indicateOptimisticFixpoint();
+
+    Changed = HasValueBefore ? ChangeStatus::UNCHANGED : ChangeStatus ::CHANGED;
+    return true;
+  }
+
   /// See AbstractAttribute::updateImpl(...).
   ChangeStatus updateImpl(Attributor &A) override {
     bool HasValueBefore = SimplifiedAssociatedValue.hasValue();
 
+    ChangeStatus Changed;
+    if (checkForNullPtrCompare(A, dyn_cast<ICmpInst>(&getAnchorValue()),
+                               Changed))
+      return Changed;
+
     auto VisitValueCB = [&](Value &V, const Instruction *CtxI, bool &,
                             bool Stripped) -> bool {
       auto &AA = A.getAAFor<AAValueSimplify>(*this, IRPosition::value(V));
       if (!Stripped && this == &AA) {
         // TODO: Look the instruction and check recursively.
 
         LLVM_DEBUG(dbgs() << "[ValueSimplify] Can't be stripped more : " << V
                           << "\n");

llvm/test/Transforms/Attributor/align.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --function-signature --scrub-attributes --check-attributes
-; RUN: opt -attributor -enable-new-pm=0 -attributor-manifest-internal  -attributor-max-iterations-verify -attributor-annotate-decl-cs -attributor-max-iterations=11 -S < %s | FileCheck %s --check-prefixes=CHECK,NOT_CGSCC_NPM,NOT_CGSCC_OPM,NOT_TUNIT_NPM,IS__TUNIT____,IS________OPM,IS__TUNIT_OPM
-; RUN: opt -aa-pipeline=basic-aa -passes=attributor -attributor-manifest-internal  -attributor-max-iterations-verify -attributor-annotate-decl-cs -attributor-max-iterations=11 -S < %s | FileCheck %s --check-prefixes=CHECK,NOT_CGSCC_OPM,NOT_CGSCC_NPM,NOT_TUNIT_OPM,IS__TUNIT____,IS________NPM,IS__TUNIT_NPM
+; RUN: opt -attributor -enable-new-pm=0 -attributor-manifest-internal  -attributor-max-iterations-verify -attributor-annotate-decl-cs -attributor-max-iterations=9 -S < %s | FileCheck %s --check-prefixes=CHECK,NOT_CGSCC_NPM,NOT_CGSCC_OPM,NOT_TUNIT_NPM,IS__TUNIT____,IS________OPM,IS__TUNIT_OPM
+; RUN: opt -aa-pipeline=basic-aa -passes=attributor -attributor-manifest-internal  -attributor-max-iterations-verify -attributor-annotate-decl-cs -attributor-max-iterations=9 -S < %s | FileCheck %s --check-prefixes=CHECK,NOT_CGSCC_OPM,NOT_CGSCC_NPM,NOT_TUNIT_OPM,IS__TUNIT____,IS________NPM,IS__TUNIT_NPM
 ; RUN: opt -attributor-cgscc -enable-new-pm=0 -attributor-manifest-internal  -attributor-annotate-decl-cs -S < %s | FileCheck %s --check-prefixes=CHECK,NOT_TUNIT_NPM,NOT_TUNIT_OPM,NOT_CGSCC_NPM,IS__CGSCC____,IS________OPM,IS__CGSCC_OPM
 ; RUN: opt -aa-pipeline=basic-aa -passes=attributor-cgscc -attributor-manifest-internal  -attributor-annotate-decl-cs -S < %s | FileCheck %s --check-prefixes=CHECK,NOT_TUNIT_NPM,NOT_TUNIT_OPM,NOT_CGSCC_OPM,IS__CGSCC____,IS________NPM,IS__CGSCC_NPM
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 
 ; Test cases specifically designed for "align" attribute.
 ; We use FIXME's to indicate problems and missing attributes.
 

 ;     return a?&a1: f1(&a2);
 ; }
 
 @a1 = common global i8 0, align 8
 @a2 = common global i8 0, align 16
 
 ; Function Attrs: nounwind readnone ssp uwtable
 define internal i8* @f1(i8* readnone %0) local_unnamed_addr #0 {
-; IS__TUNIT____: Function Attrs: nofree noinline nosync nounwind readnone uwtable
+; IS__TUNIT____: Function Attrs: nofree noinline nosync nounwind readnone uwtable willreturn
 ; IS__TUNIT____-LABEL: define {{[^@]+}}@f1
-; IS__TUNIT____-SAME: (i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) "no-capture-maybe-returned" [[TMP0:%.*]]) local_unnamed_addr
-; IS__TUNIT____-NEXT:    [[TMP2:%.*]] = icmp eq i8* [[TMP0]], null
-; IS__TUNIT____-NEXT:    br i1 [[TMP2]], label [[TMP3:%.*]], label [[TMP5:%.*]]
+; IS__TUNIT____-SAME: (i8* noalias nofree noundef nonnull readnone returned align 8 dereferenceable(1) "no-capture-maybe-returned" [[TMP0:%.*]]) local_unnamed_addr
+; IS__TUNIT____-NEXT:    br label [[TMP3:%.*]]
+; IS__TUNIT____:       2:
+; IS__TUNIT____-NEXT:    unreachable
 ; IS__TUNIT____:       3:
-; IS__TUNIT____-NEXT:    [[TMP4:%.*]] = tail call align 8 i8* @f2()
-; IS__TUNIT____-NEXT:    br label [[TMP5]]
-; IS__TUNIT____:       5:
-; IS__TUNIT____-NEXT:    [[TMP6:%.*]] = phi i8* [ [[TMP4]], [[TMP3]] ], [ [[TMP0]], [[TMP1:%.*]] ]
-; IS__TUNIT____-NEXT:    ret i8* [[TMP6]]
-;
-; IS__CGSCC____: Function Attrs: nofree noinline nosync nounwind readnone uwtable
-; IS__CGSCC____-LABEL: define {{[^@]+}}@f1
-; IS__CGSCC____-SAME: (i8* nofree noundef nonnull readnone align 8 dereferenceable(1) "no-capture-maybe-returned" [[TMP0:%.*]]) local_unnamed_addr
-; IS__CGSCC____-NEXT:    [[TMP2:%.*]] = icmp eq i8* [[TMP0]], null
-; IS__CGSCC____-NEXT:    br i1 [[TMP2]], label [[TMP3:%.*]], label [[TMP5:%.*]]
-; IS__CGSCC____:       3:
-; IS__CGSCC____-NEXT:    [[TMP4:%.*]] = tail call align 8 i8* @f2()
-; IS__CGSCC____-NEXT:    br label [[TMP5]]
-; IS__CGSCC____:       5:
-; IS__CGSCC____-NEXT:    [[TMP6:%.*]] = phi i8* [ [[TMP4]], [[TMP3]] ], [ [[TMP0]], [[TMP1:%.*]] ]
-; IS__CGSCC____-NEXT:    ret i8* [[TMP6]]
+; IS__TUNIT____-NEXT:    ret i8* [[TMP0]]
+;
+; IS__CGSCC_OPM: Function Attrs: nofree noinline nosync nounwind readnone uwtable willreturn
+; IS__CGSCC_OPM-LABEL: define {{[^@]+}}@f1
+; IS__CGSCC_OPM-SAME: (i8* nofree noundef nonnull readnone returned align 8 dereferenceable(1) "no-capture-maybe-returned" [[TMP0:%.*]]) local_unnamed_addr
+; IS__CGSCC_OPM-NEXT:    br label [[TMP3:%.*]]
+; IS__CGSCC_OPM:       2:
+; IS__CGSCC_OPM-NEXT:    unreachable
+; IS__CGSCC_OPM:       3:
+; IS__CGSCC_OPM-NEXT:    ret i8* [[TMP0]]
+;
+; IS__CGSCC_NPM: Function Attrs: nofree noinline norecurse nosync nounwind readnone uwtable willreturn
+; IS__CGSCC_NPM-LABEL: define {{[^@]+}}@f1() local_unnamed_addr
+; IS__CGSCC_NPM-NEXT:    br label [[TMP2:%.*]]
+; IS__CGSCC_NPM:       1:
+; IS__CGSCC_NPM-NEXT:    unreachable
+; IS__CGSCC_NPM:       2:
+; IS__CGSCC_NPM-NEXT:    ret i8* @a1
 ;
   %2 = icmp eq i8* %0, null
   br i1 %2, label %3, label %5
 
 ; <label>:3:                                      ; preds = %1
   %4 = tail call i8* @f2(i8* nonnull @a1)
   %l = load i8, i8* %4
   br label %5
 
 ; <label>:5:                                      ; preds = %1, %3
   %6 = phi i8* [ %4, %3 ], [ %0, %1 ]
   ret i8* %6
 }
 
 ; Function Attrs: nounwind readnone ssp uwtable
 define internal i8* @f2(i8* readnone %0) local_unnamed_addr #0 {
-; CHECK: Function Attrs: nofree noinline nosync nounwind readnone uwtable
-; CHECK-LABEL: define {{[^@]+}}@f2() local_unnamed_addr
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp eq i8* @a1, null
-; CHECK-NEXT:    br i1 [[TMP1]], label [[TMP4:%.*]], label [[TMP2:%.*]]
-; CHECK:       2:
-; CHECK-NEXT:    [[TMP3:%.*]] = tail call i8* @f1(i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) "no-capture-maybe-returned" @a1)
-; CHECK-NEXT:    br label [[TMP6:%.*]]
-; CHECK:       4:
-; CHECK-NEXT:    [[TMP5:%.*]] = tail call i8* @f3()
-; CHECK-NEXT:    br label [[TMP6]]
-; CHECK:       6:
-; CHECK-NEXT:    [[TMP7:%.*]] = phi i8* [ [[TMP3]], [[TMP2]] ], [ [[TMP5]], [[TMP4]] ]
-; CHECK-NEXT:    ret i8* [[TMP7]]
-;
   %2 = icmp eq i8* %0, null
   br i1 %2, label %5, label %3
 
 ; <label>:3:                                      ; preds = %1
 
   %4 = tail call i8* @f1(i8* nonnull %0)
   br label %7
 
 ; <label>:5:                                      ; preds = %1
   %6 = tail call i8* @f3(i8* nonnull @a2)
   br label %7
 
 ; <label>:7:                                      ; preds = %5, %3
   %8 = phi i8* [ %4, %3 ], [ %6, %5 ]
   ret i8* %8
 }
 
 ; Function Attrs: nounwind readnone ssp uwtable
 define internal i8* @f3(i8* readnone %0) local_unnamed_addr #0 {
-; CHECK: Function Attrs: nofree noinline nosync nounwind readnone uwtable
-; CHECK-LABEL: define {{[^@]+}}@f3() local_unnamed_addr
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp eq i8* @a2, null
-; CHECK-NEXT:    br i1 [[TMP1]], label [[TMP2:%.*]], label [[TMP4:%.*]]
-; CHECK:       2:
-; CHECK-NEXT:    [[TMP3:%.*]] = tail call i8* @f1(i8* noalias nofree noundef nonnull readnone align 16 dereferenceable(1) "no-capture-maybe-returned" @a2)
-; CHECK-NEXT:    br label [[TMP4]]
-; CHECK:       4:
-; CHECK-NEXT:    [[TMP5:%.*]] = phi i8* [ [[TMP3]], [[TMP2]] ], [ @a1, [[TMP0:%.*]] ]
-; CHECK-NEXT:    ret i8* [[TMP5]]
-;
   %2 = icmp eq i8* %0, null
   br i1 %2, label %3, label %5
 
 ; <label>:3:                                      ; preds = %1
   %4 = tail call i8* @f1(i8* nonnull @a2)
   br label %5
 
 ; <label>:5:                                      ; preds = %1, %3
   %6 = phi i8* [ %4, %3 ], [ @a1, %1 ]
   ret i8* %6
 }
 
 ; TEST 7
 ; Better than IR information
 define align 4 i8* @test7() #0 {
-; IS__TUNIT____: Function Attrs: nofree noinline nosync nounwind readnone uwtable
+; IS__TUNIT____: Function Attrs: nofree noinline nosync nounwind readnone uwtable willreturn
 ; IS__TUNIT____-LABEL: define {{[^@]+}}@test7()
 ; IS__TUNIT____-NEXT:    [[C:%.*]] = tail call i8* @f1(i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) "no-capture-maybe-returned" @a1)
 ; IS__TUNIT____-NEXT:    ret i8* [[C]]
 ;
-; IS__CGSCC____: Function Attrs: nofree noinline nosync nounwind readnone uwtable
-; IS__CGSCC____-LABEL: define {{[^@]+}}@test7()
-; IS__CGSCC____-NEXT:    [[C:%.*]] = tail call nonnull align 8 dereferenceable(1) i8* @f1(i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) @a1)
-; IS__CGSCC____-NEXT:    ret i8* [[C]]
+; IS__CGSCC_OPM: Function Attrs: nofree noinline nosync nounwind readnone uwtable willreturn
+; IS__CGSCC_OPM-LABEL: define {{[^@]+}}@test7()
+; IS__CGSCC_OPM-NEXT:    [[C:%.*]] = tail call i8* @f1(i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) @a1)
+; IS__CGSCC_OPM-NEXT:    ret i8* [[C]]
+;
+; IS__CGSCC_NPM: Function Attrs: nofree noinline norecurse nosync nounwind readnone uwtable willreturn
+; IS__CGSCC_NPM-LABEL: define {{[^@]+}}@test7()
+; IS__CGSCC_NPM-NEXT:    [[C:%.*]] = tail call nonnull align 8 dereferenceable(1) i8* @f1()
+; IS__CGSCC_NPM-NEXT:    ret i8* [[C]]
 ;
   %c = tail call i8* @f1(i8* align 8 dereferenceable(1) @a1)
   ret i8* %c
 }
 
 ; TEST 7b
 ; Function Attrs: nounwind readnone ssp uwtable
 define internal i8* @f1b(i8* readnone %0) local_unnamed_addr #0 {
-; IS__TUNIT____: Function Attrs: nofree noinline nosync nounwind uwtable
-; IS__TUNIT____-LABEL: define {{[^@]+}}@f1b
-; IS__TUNIT____-SAME: (i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) "no-capture-maybe-returned" [[TMP0:%.*]]) local_unnamed_addr
-; IS__TUNIT____-NEXT:    [[TMP2:%.*]] = icmp eq i8* [[TMP0]], null
-; IS__TUNIT____-NEXT:    br i1 [[TMP2]], label [[TMP3:%.*]], label [[TMP5:%.*]]
-; IS__TUNIT____:       3:
-; IS__TUNIT____-NEXT:    [[TMP4:%.*]] = tail call align 8 i8* @f2b()
-; IS__TUNIT____-NEXT:    [[L:%.*]] = load i8, i8* [[TMP4]], align 8
-; IS__TUNIT____-NEXT:    store i8 [[L]], i8* @a1, align 8
-; IS__TUNIT____-NEXT:    br label [[TMP5]]
-; IS__TUNIT____:       5:
-; IS__TUNIT____-NEXT:    [[TMP6:%.*]] = phi i8* [ [[TMP4]], [[TMP3]] ], [ [[TMP0]], [[TMP1:%.*]] ]
-; IS__TUNIT____-NEXT:    ret i8* [[TMP6]]
-;
-; IS__CGSCC____: Function Attrs: nofree noinline nosync nounwind uwtable
-; IS__CGSCC____-LABEL: define {{[^@]+}}@f1b
-; IS__CGSCC____-SAME: (i8* nofree noundef nonnull readnone align 8 dereferenceable(1) "no-capture-maybe-returned" [[TMP0:%.*]]) local_unnamed_addr
-; IS__CGSCC____-NEXT:    [[TMP2:%.*]] = icmp eq i8* [[TMP0]], null
-; IS__CGSCC____-NEXT:    br i1 [[TMP2]], label [[TMP3:%.*]], label [[TMP5:%.*]]
-; IS__CGSCC____:       3:
-; IS__CGSCC____-NEXT:    [[TMP4:%.*]] = tail call align 8 i8* @f2b()
-; IS__CGSCC____-NEXT:    [[L:%.*]] = load i8, i8* [[TMP4]], align 8
-; IS__CGSCC____-NEXT:    store i8 [[L]], i8* @a1, align 8
-; IS__CGSCC____-NEXT:    br label [[TMP5]]
-; IS__CGSCC____:       5:
-; IS__CGSCC____-NEXT:    [[TMP6:%.*]] = phi i8* [ [[TMP4]], [[TMP3]] ], [ [[TMP0]], [[TMP1:%.*]] ]
-; IS__CGSCC____-NEXT:    ret i8* [[TMP6]]
+; IS__CGSCC_OPM: Function Attrs: nofree noinline nosync nounwind readnone uwtable willreturn
+; IS__CGSCC_OPM-LABEL: define {{[^@]+}}@f1b
+; IS__CGSCC_OPM-SAME: (i8* nofree noundef nonnull readnone returned align 8 dereferenceable(1) "no-capture-maybe-returned" [[TMP0:%.*]]) local_unnamed_addr
+; IS__CGSCC_OPM-NEXT:    br label [[TMP3:%.*]]
+; IS__CGSCC_OPM:       2:
+; IS__CGSCC_OPM-NEXT:    unreachable
+; IS__CGSCC_OPM:       3:
+; IS__CGSCC_OPM-NEXT:    ret i8* [[TMP0]]
+;
+; IS__CGSCC_NPM: Function Attrs: nofree noinline norecurse nosync nounwind readnone uwtable willreturn
+; IS__CGSCC_NPM-LABEL: define {{[^@]+}}@f1b() local_unnamed_addr
+; IS__CGSCC_NPM-NEXT:    br label [[TMP2:%.*]]
+; IS__CGSCC_NPM:       1:
+; IS__CGSCC_NPM-NEXT:    unreachable
+; IS__CGSCC_NPM:       2:
+; IS__CGSCC_NPM-NEXT:    ret i8* undef
 ;
   %2 = icmp eq i8* %0, null
   br i1 %2, label %3, label %5
 
 ; <label>:3:                                      ; preds = %1
   %4 = tail call i8* @f2b(i8* nonnull @a1)
   %l = load i8, i8* %4
   store i8 %l, i8* @a1
   br label %5
 
 ; <label>:5:                                      ; preds = %1, %3
   %6 = phi i8* [ %4, %3 ], [ %0, %1 ]
   ret i8* %6
 }
 
 ; Function Attrs: nounwind readnone ssp uwtable
 define internal i8* @f2b(i8* readnone %0) local_unnamed_addr #0 {
 ;
-; CHECK: Function Attrs: nofree noinline nosync nounwind uwtable
-; CHECK-LABEL: define {{[^@]+}}@f2b() local_unnamed_addr
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp eq i8* @a1, null
-; CHECK-NEXT:    br i1 [[TMP1]], label [[TMP4:%.*]], label [[TMP2:%.*]]
-; CHECK:       2:
-; CHECK-NEXT:    [[TMP3:%.*]] = tail call i8* @f1b(i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) "no-capture-maybe-returned" @a1)
-; CHECK-NEXT:    br label [[TMP6:%.*]]
-; CHECK:       4:
-; CHECK-NEXT:    [[TMP5:%.*]] = tail call i8* @f3b()
-; CHECK-NEXT:    br label [[TMP6]]
-; CHECK:       6:
-; CHECK-NEXT:    [[TMP7:%.*]] = phi i8* [ [[TMP3]], [[TMP2]] ], [ [[TMP5]], [[TMP4]] ]
-; CHECK-NEXT:    ret i8* [[TMP7]]
-;
   %2 = icmp eq i8* %0, null
   br i1 %2, label %5, label %3
 
 ; <label>:3:                                      ; preds = %1
 
   %4 = tail call i8* @f1b(i8* nonnull %0)
   br label %7
 
 ; <label>:5:                                      ; preds = %1
   %6 = tail call i8* @f3b(i8* nonnull @a2)
   br label %7
 
 ; <label>:7:                                      ; preds = %5, %3
   %8 = phi i8* [ %4, %3 ], [ %6, %5 ]
   ret i8* %8
 }
 
 ; Function Attrs: nounwind readnone ssp uwtable
 define internal i8* @f3b(i8* readnone %0) local_unnamed_addr #0 {
 ;
-; CHECK: Function Attrs: nofree noinline nosync nounwind uwtable
-; CHECK-LABEL: define {{[^@]+}}@f3b() local_unnamed_addr
-; CHECK-NEXT:    [[TMP1:%.*]] = icmp eq i8* @a2, null
-; CHECK-NEXT:    br i1 [[TMP1]], label [[TMP2:%.*]], label [[TMP4:%.*]]
-; CHECK:       2:
-; CHECK-NEXT:    [[TMP3:%.*]] = tail call i8* @f1b(i8* noalias nofree noundef nonnull readnone align 16 dereferenceable(1) "no-capture-maybe-returned" @a2)
-; CHECK-NEXT:    br label [[TMP4]]
-; CHECK:       4:
-; CHECK-NEXT:    [[TMP5:%.*]] = phi i8* [ [[TMP3]], [[TMP2]] ], [ @a1, [[TMP0:%.*]] ]
-; CHECK-NEXT:    ret i8* [[TMP5]]
-;
   %2 = icmp eq i8* %0, null
   br i1 %2, label %3, label %5
 
 ; <label>:3:                                      ; preds = %1
   %4 = tail call i8* @f1b(i8* nonnull @a2)
   br label %5
 
 ; <label>:5:                                      ; preds = %1, %3
   %6 = phi i8* [ %4, %3 ], [ @a1, %1 ]
   ret i8* %6
 }
 
 define align 4 i32* @test7b(i32* align 32 %p) #0 {
-; IS__TUNIT____: Function Attrs: nofree noinline nosync nounwind uwtable
+; IS__TUNIT____: Function Attrs: nofree noinline nosync nounwind readnone uwtable willreturn
 ; IS__TUNIT____-LABEL: define {{[^@]+}}@test7b
 ; IS__TUNIT____-SAME: (i32* nofree readnone returned align 32 "no-capture-maybe-returned" [[P:%.*]])
-; IS__TUNIT____-NEXT:    [[TMP1:%.*]] = tail call i8* @f1b(i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) "no-capture-maybe-returned" @a1)
 ; IS__TUNIT____-NEXT:    ret i32* [[P]]
 ;
-; IS__CGSCC____: Function Attrs: nofree noinline nosync nounwind uwtable
+; IS__CGSCC____: Function Attrs: nofree noinline norecurse nosync nounwind readnone uwtable willreturn
 ; IS__CGSCC____-LABEL: define {{[^@]+}}@test7b
 ; IS__CGSCC____-SAME: (i32* nofree readnone returned align 32 "no-capture-maybe-returned" [[P:%.*]])
-; IS__CGSCC____-NEXT:    [[TMP1:%.*]] = tail call i8* @f1b(i8* noalias nofree noundef nonnull readnone align 8 dereferenceable(1) @a1)
 ; IS__CGSCC____-NEXT:    ret i32* [[P]]
 ;
   tail call i8* @f1b(i8* align 8 dereferenceable(1) @a1)
   ret i32* %p
 }
 
 ; TEST 8
 define void @test8_helper() {

llvm/test/Transforms/Attributor/nocapture-1.ll

;
   %1 = icmp eq i32* null, %x
   ret i1 %1
 }
 
 define i1 @nocaptureInboundsGEPICmp(i32* %x) {
 ; IS__TUNIT____: Function Attrs: nofree nosync nounwind readnone willreturn
 ; IS__TUNIT____-LABEL: define {{[^@]+}}@nocaptureInboundsGEPICmp
 ; IS__TUNIT____-SAME: (i32* nocapture nofree readnone [[X:%.*]])
-; IS__TUNIT____-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i32, i32* [[X]], i32 5
-; IS__TUNIT____-NEXT:    [[TMP2:%.*]] = bitcast i32* [[TMP1]] to i8*
-; IS__TUNIT____-NEXT:    [[TMP3:%.*]] = icmp eq i8* [[TMP2]], null
-; IS__TUNIT____-NEXT:    ret i1 [[TMP3]]
+; IS__TUNIT____-NEXT:    ret i1 false
 ;
 ; IS__CGSCC____: Function Attrs: nofree norecurse nosync nounwind readnone willreturn
 ; IS__CGSCC____-LABEL: define {{[^@]+}}@nocaptureInboundsGEPICmp
 ; IS__CGSCC____-SAME: (i32* nocapture nofree readnone [[X:%.*]])
-; IS__CGSCC____-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i32, i32* [[X]], i32 5
-; IS__CGSCC____-NEXT:    [[TMP2:%.*]] = bitcast i32* [[TMP1]] to i8*
-; IS__CGSCC____-NEXT:    [[TMP3:%.*]] = icmp eq i8* [[TMP2]], null
-; IS__CGSCC____-NEXT:    ret i1 [[TMP3]]
+; IS__CGSCC____-NEXT:    ret i1 false
 ;
   %1 = getelementptr inbounds i32, i32* %x, i32 5
   %2 = bitcast i32* %1 to i8*
   %3 = icmp eq i8* %2, null
   ret i1 %3
 }
 
 define i1 @nocaptureInboundsGEPICmpRev(i32* %x) {
 ; IS__TUNIT____: Function Attrs: nofree nosync nounwind readnone willreturn
 ; IS__TUNIT____-LABEL: define {{[^@]+}}@nocaptureInboundsGEPICmpRev
 ; IS__TUNIT____-SAME: (i32* nocapture nofree readnone [[X:%.*]])
-; IS__TUNIT____-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i32, i32* [[X]], i32 5
-; IS__TUNIT____-NEXT:    [[TMP2:%.*]] = bitcast i32* [[TMP1]] to i8*
-; IS__TUNIT____-NEXT:    [[TMP3:%.*]] = icmp eq i8* null, [[TMP2]]
-; IS__TUNIT____-NEXT:    ret i1 [[TMP3]]
+; IS__TUNIT____-NEXT:    ret i1 true
 ;
 ; IS__CGSCC____: Function Attrs: nofree norecurse nosync nounwind readnone willreturn
 ; IS__CGSCC____-LABEL: define {{[^@]+}}@nocaptureInboundsGEPICmpRev
 ; IS__CGSCC____-SAME: (i32* nocapture nofree readnone [[X:%.*]])
-; IS__CGSCC____-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i32, i32* [[X]], i32 5
-; IS__CGSCC____-NEXT:    [[TMP2:%.*]] = bitcast i32* [[TMP1]] to i8*
-; IS__CGSCC____-NEXT:    [[TMP3:%.*]] = icmp eq i8* null, [[TMP2]]
-; IS__CGSCC____-NEXT:    ret i1 [[TMP3]]
+; IS__CGSCC____-NEXT:    ret i1 true
 ;
   %1 = getelementptr inbounds i32, i32* %x, i32 5
   %2 = bitcast i32* %1 to i8*
-  %3 = icmp eq i8* null, %2
+  %3 = icmp ne i8* null, %2
   ret i1 %3
 }
 
 define i1 @nocaptureDereferenceableOrNullICmp(i32* dereferenceable_or_null(4) %x) {
 ; IS__TUNIT____: Function Attrs: nofree nosync nounwind readnone willreturn
 ; IS__TUNIT____-LABEL: define {{[^@]+}}@nocaptureDereferenceableOrNullICmp
 ; IS__TUNIT____-SAME: (i32* nocapture nofree readnone dereferenceable_or_null(4) [[X:%.*]])
 ; IS__TUNIT____-NEXT:    [[TMP1:%.*]] = bitcast i32* [[X]] to i8*

llvm/test/Transforms/Attributor/nonnull.ll

 define i1 @parent8(i8* %a, i8* %bogus1, i8* %b) personality i8* bitcast (i32 (...)* @esfp to i8*){
 ; CHECK: Function Attrs: nounwind
 ; CHECK-LABEL: define {{[^@]+}}@parent8
 ; CHECK-SAME: (i8* nonnull [[A:%.*]], i8* nocapture nofree readnone [[BOGUS1:%.*]], i8* nonnull [[B:%.*]]) [[ATTR4:#.*]] personality i8* bitcast (i32 (...)* @esfp to i8*)
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    invoke void @use2nonnull(i8* nonnull [[A]], i8* nonnull [[B]])
 ; CHECK-NEXT:    to label [[CONT:%.*]] unwind label [[EXC:%.*]]
 ; CHECK:       cont:
-; CHECK-NEXT:    [[NULL_CHECK:%.*]] = icmp eq i8* [[B]], null
-; CHECK-NEXT:    ret i1 [[NULL_CHECK]]
+; CHECK-NEXT:    ret i1 false
 ; CHECK:       exc:
 ; CHECK-NEXT:    [[LP:%.*]] = landingpad { i8*, i32 }
 ; CHECK-NEXT:    filter [0 x i8*] zeroinitializer
 ; CHECK-NEXT:    unreachable
 ;
 
 entry:
   invoke void @use2nonnull(i8* %a, i8* %b)