[llvm] 027e7a7 - Reland "[NFC][SCEV] Improve tests for ptrtoint modelling (D88806)"
Roman Lebedev via llvm-commits
llvm-commits at lists.llvm.org
Fri Oct 9 04:50:34 PDT 2020
Author: Roman Lebedev
Date: 2020-10-09T14:50:05+03:00
New Revision: 027e7a7721753ea35e339b05dd3439d310c6ecae
URL: https://github.com/llvm/llvm-project/commit/027e7a7721753ea35e339b05dd3439d310c6ecae
DIFF: https://github.com/llvm/llvm-project/commit/027e7a7721753ea35e339b05dd3439d310c6ecae.diff
LOG: Reland "[NFC][SCEV] Improve tests for ptrtoint modelling (D88806)"
I messed up runlines in the original commit.
Added:
llvm/test/Analysis/ScalarEvolution/ptrtoint.ll
Modified:
Removed:
llvm/test/Analysis/ScalarEvolution/semi-transparent-inttoptr-ptrtoint-casts.ll
################################################################################
diff --git a/llvm/test/Analysis/ScalarEvolution/ptrtoint.ll b/llvm/test/Analysis/ScalarEvolution/ptrtoint.ll
new file mode 100644
index 000000000000..e3e9330e241f
--- /dev/null
+++ b/llvm/test/Analysis/ScalarEvolution/ptrtoint.ll
@@ -0,0 +1,239 @@
+; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
+; RUN: opt < %s --data-layout="e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" -S -analyze -enable-new-pm=0 -scalar-evolution | FileCheck --check-prefixes=ALL,X64 %s
+; RUN: opt < %s --data-layout="e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128" -S -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck --check-prefixes=ALL,X64 %s
+; RUN: opt < %s --data-layout="e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128" -S -analyze -enable-new-pm=0 -scalar-evolution | FileCheck --check-prefixes=ALL,X32 %s
+; RUN: opt < %s --data-layout="e-m:e-p:32:32-p270:32:32-p271:32:32-p272:64:64-f64:32:64-f80:32-n8:16:32-S128" -S -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck --check-prefixes=ALL,X32 %s
+
+; While we can't treat inttoptr/ptrtoint casts as fully transparent,
+; for ptrtoint cast, instead of modelling it as fully opaque (unknown),
+; we can at least model it as zext/trunc/self of an unknown,
+; iff it it's argument would be modelled as unknown anyways.
+
+declare void @useptr(i8*)
+
+; Simple ptrtoint of an argument, with casts to potentially
diff erent bit widths.
+define void @ptrtoint(i8* %in, i64* %out0, i32* %out1, i16* %out2, i128* %out3) {
+; X64-LABEL: 'ptrtoint'
+; X64-NEXT: Classifying expressions for: @ptrtoint
+; X64-NEXT: %p0 = ptrtoint i8* %in to i64
+; X64-NEXT: --> %p0 U: full-set S: full-set
+; X64-NEXT: %p1 = ptrtoint i8* %in to i32
+; X64-NEXT: --> %p1 U: full-set S: full-set
+; X64-NEXT: %p2 = ptrtoint i8* %in to i16
+; X64-NEXT: --> %p2 U: full-set S: full-set
+; X64-NEXT: %p3 = ptrtoint i8* %in to i128
+; X64-NEXT: --> %p3 U: [0,18446744073709551616) S: [-18446744073709551616,18446744073709551616)
+; X64-NEXT: Determining loop execution counts for: @ptrtoint
+;
+; X32-LABEL: 'ptrtoint'
+; X32-NEXT: Classifying expressions for: @ptrtoint
+; X32-NEXT: %p0 = ptrtoint i8* %in to i64
+; X32-NEXT: --> %p0 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: %p1 = ptrtoint i8* %in to i32
+; X32-NEXT: --> %p1 U: full-set S: full-set
+; X32-NEXT: %p2 = ptrtoint i8* %in to i16
+; X32-NEXT: --> %p2 U: full-set S: full-set
+; X32-NEXT: %p3 = ptrtoint i8* %in to i128
+; X32-NEXT: --> %p3 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: Determining loop execution counts for: @ptrtoint
+;
+ %p0 = ptrtoint i8* %in to i64
+ %p1 = ptrtoint i8* %in to i32
+ %p2 = ptrtoint i8* %in to i16
+ %p3 = ptrtoint i8* %in to i128
+ store i64 %p0, i64* %out0
+ store i32 %p1, i32* %out1
+ store i16 %p2, i16* %out2
+ store i128 %p3, i128* %out3
+ ret void
+}
+
+; Same, but from non-zero/non-default address space.
+define void @ptrtoint_as1(i8 addrspace(1)* %in, i64* %out0, i32* %out1, i16* %out2, i128* %out3) {
+; X64-LABEL: 'ptrtoint_as1'
+; X64-NEXT: Classifying expressions for: @ptrtoint_as1
+; X64-NEXT: %p0 = ptrtoint i8 addrspace(1)* %in to i64
+; X64-NEXT: --> %p0 U: full-set S: full-set
+; X64-NEXT: %p1 = ptrtoint i8 addrspace(1)* %in to i32
+; X64-NEXT: --> %p1 U: full-set S: full-set
+; X64-NEXT: %p2 = ptrtoint i8 addrspace(1)* %in to i16
+; X64-NEXT: --> %p2 U: full-set S: full-set
+; X64-NEXT: %p3 = ptrtoint i8 addrspace(1)* %in to i128
+; X64-NEXT: --> %p3 U: [0,18446744073709551616) S: [-18446744073709551616,18446744073709551616)
+; X64-NEXT: Determining loop execution counts for: @ptrtoint_as1
+;
+; X32-LABEL: 'ptrtoint_as1'
+; X32-NEXT: Classifying expressions for: @ptrtoint_as1
+; X32-NEXT: %p0 = ptrtoint i8 addrspace(1)* %in to i64
+; X32-NEXT: --> %p0 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: %p1 = ptrtoint i8 addrspace(1)* %in to i32
+; X32-NEXT: --> %p1 U: full-set S: full-set
+; X32-NEXT: %p2 = ptrtoint i8 addrspace(1)* %in to i16
+; X32-NEXT: --> %p2 U: full-set S: full-set
+; X32-NEXT: %p3 = ptrtoint i8 addrspace(1)* %in to i128
+; X32-NEXT: --> %p3 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: Determining loop execution counts for: @ptrtoint_as1
+;
+ %p0 = ptrtoint i8 addrspace(1)* %in to i64
+ %p1 = ptrtoint i8 addrspace(1)* %in to i32
+ %p2 = ptrtoint i8 addrspace(1)* %in to i16
+ %p3 = ptrtoint i8 addrspace(1)* %in to i128
+ store i64 %p0, i64* %out0
+ store i32 %p1, i32* %out1
+ store i16 %p2, i16* %out2
+ store i128 %p3, i128* %out3
+ ret void
+}
+
+; Likewise, ptrtoint of a bitcast is fine, we simply skip it.
+define void @ptrtoint_of_bitcast(i8* %in, i64* %out0) {
+; X64-LABEL: 'ptrtoint_of_bitcast'
+; X64-NEXT: Classifying expressions for: @ptrtoint_of_bitcast
+; X64-NEXT: %in_casted = bitcast i8* %in to float*
+; X64-NEXT: --> %in U: full-set S: full-set
+; X64-NEXT: %p0 = ptrtoint float* %in_casted to i64
+; X64-NEXT: --> %p0 U: full-set S: full-set
+; X64-NEXT: Determining loop execution counts for: @ptrtoint_of_bitcast
+;
+; X32-LABEL: 'ptrtoint_of_bitcast'
+; X32-NEXT: Classifying expressions for: @ptrtoint_of_bitcast
+; X32-NEXT: %in_casted = bitcast i8* %in to float*
+; X32-NEXT: --> %in U: full-set S: full-set
+; X32-NEXT: %p0 = ptrtoint float* %in_casted to i64
+; X32-NEXT: --> %p0 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: Determining loop execution counts for: @ptrtoint_of_bitcast
+;
+ %in_casted = bitcast i8* %in to float*
+ %p0 = ptrtoint float* %in_casted to i64
+ store i64 %p0, i64* %out0
+ ret void
+}
+
+; addrspacecast is fine too, but We don't model addrspacecast, so we stop there.
+define void @ptrtoint_of_addrspacecast(i8* %in, i64* %out0) {
+; X64-LABEL: 'ptrtoint_of_addrspacecast'
+; X64-NEXT: Classifying expressions for: @ptrtoint_of_addrspacecast
+; X64-NEXT: %in_casted = addrspacecast i8* %in to i8 addrspace(1)*
+; X64-NEXT: --> %in_casted U: full-set S: full-set
+; X64-NEXT: %p0 = ptrtoint i8 addrspace(1)* %in_casted to i64
+; X64-NEXT: --> %p0 U: full-set S: full-set
+; X64-NEXT: Determining loop execution counts for: @ptrtoint_of_addrspacecast
+;
+; X32-LABEL: 'ptrtoint_of_addrspacecast'
+; X32-NEXT: Classifying expressions for: @ptrtoint_of_addrspacecast
+; X32-NEXT: %in_casted = addrspacecast i8* %in to i8 addrspace(1)*
+; X32-NEXT: --> %in_casted U: full-set S: full-set
+; X32-NEXT: %p0 = ptrtoint i8 addrspace(1)* %in_casted to i64
+; X32-NEXT: --> %p0 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: Determining loop execution counts for: @ptrtoint_of_addrspacecast
+;
+ %in_casted = addrspacecast i8* %in to i8 addrspace(1)*
+ %p0 = ptrtoint i8 addrspace(1)* %in_casted to i64
+ store i64 %p0, i64* %out0
+ ret void
+}
+
+; inttoptr is fine too, but we don't (and can't) model inttoptr, so we stop there.
+define void @ptrtoint_of_inttoptr(i64 %in, i64* %out0) {
+; X64-LABEL: 'ptrtoint_of_inttoptr'
+; X64-NEXT: Classifying expressions for: @ptrtoint_of_inttoptr
+; X64-NEXT: %in_casted = inttoptr i64 %in to i8*
+; X64-NEXT: --> %in_casted U: full-set S: full-set
+; X64-NEXT: %p0 = ptrtoint i8* %in_casted to i64
+; X64-NEXT: --> %p0 U: full-set S: full-set
+; X64-NEXT: Determining loop execution counts for: @ptrtoint_of_inttoptr
+;
+; X32-LABEL: 'ptrtoint_of_inttoptr'
+; X32-NEXT: Classifying expressions for: @ptrtoint_of_inttoptr
+; X32-NEXT: %in_casted = inttoptr i64 %in to i8*
+; X32-NEXT: --> %in_casted U: full-set S: full-set
+; X32-NEXT: %p0 = ptrtoint i8* %in_casted to i64
+; X32-NEXT: --> %p0 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: Determining loop execution counts for: @ptrtoint_of_inttoptr
+;
+ %in_casted = inttoptr i64 %in to i8*
+ %p0 = ptrtoint i8* %in_casted to i64
+ store i64 %p0, i64* %out0
+ ret void
+}
+
+; However, GEP is something SCEV knows how to model, so in this case ptrtoint
+; can't be modelled as a cast, only as an unknown.
+define void @ptrtoint_of_gep(i8* %in, i64* %out0) {
+; X64-LABEL: 'ptrtoint_of_gep'
+; X64-NEXT: Classifying expressions for: @ptrtoint_of_gep
+; X64-NEXT: %in_adj = getelementptr inbounds i8, i8* %in, i64 42
+; X64-NEXT: --> (42 + %in)<nsw> U: [-9223372036854775766,-9223372036854775808) S: [-9223372036854775766,-9223372036854775808)
+; X64-NEXT: %p0 = ptrtoint i8* %in_adj to i64
+; X64-NEXT: --> %p0 U: full-set S: full-set
+; X64-NEXT: Determining loop execution counts for: @ptrtoint_of_gep
+;
+; X32-LABEL: 'ptrtoint_of_gep'
+; X32-NEXT: Classifying expressions for: @ptrtoint_of_gep
+; X32-NEXT: %in_adj = getelementptr inbounds i8, i8* %in, i64 42
+; X32-NEXT: --> (42 + %in)<nsw> U: [-2147483606,-2147483648) S: [-2147483606,-2147483648)
+; X32-NEXT: %p0 = ptrtoint i8* %in_adj to i64
+; X32-NEXT: --> %p0 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: Determining loop execution counts for: @ptrtoint_of_gep
+;
+ %in_adj = getelementptr inbounds i8, i8* %in, i64 42
+ %p0 = ptrtoint i8* %in_adj to i64
+ store i64 %p0, i64* %out0
+ ret void
+}
+
+; A constant pointer is fine
+define void @ptrtoint_of_nullptr(i64* %out0) {
+; ALL-LABEL: 'ptrtoint_of_nullptr'
+; ALL-NEXT: Classifying expressions for: @ptrtoint_of_nullptr
+; ALL-NEXT: %p0 = ptrtoint i8* null to i64
+; ALL-NEXT: --> %p0 U: [0,1) S: [-1,1)
+; ALL-NEXT: Determining loop execution counts for: @ptrtoint_of_nullptr
+;
+ %p0 = ptrtoint i8* null to i64
+ store i64 %p0, i64* %out0
+ ret void
+}
+
+; A constant inttoptr argument of an ptrtoint is still bad.
+define void @ptrtoint_of_constantexpr_inttoptr(i64* %out0) {
+; ALL-LABEL: 'ptrtoint_of_constantexpr_inttoptr'
+; ALL-NEXT: Classifying expressions for: @ptrtoint_of_constantexpr_inttoptr
+; ALL-NEXT: %p0 = ptrtoint i8* inttoptr (i64 42 to i8*) to i64
+; ALL-NEXT: --> %p0 U: [42,43) S: [-64,64)
+; ALL-NEXT: Determining loop execution counts for: @ptrtoint_of_constantexpr_inttoptr
+;
+ %p0 = ptrtoint i8* inttoptr (i64 42 to i8*) to i64
+ store i64 %p0, i64* %out0
+ ret void
+}
+
+; However, while bitcast would be fine, GEP we can model, so we are back
+; to modelling the whole cast as unknown..
+define void @ptrtoint_of_bitcast_of_gep(i8* %in, i64* %out0) {
+; X64-LABEL: 'ptrtoint_of_bitcast_of_gep'
+; X64-NEXT: Classifying expressions for: @ptrtoint_of_bitcast_of_gep
+; X64-NEXT: %in_adj = getelementptr inbounds i8, i8* %in, i64 42
+; X64-NEXT: --> (42 + %in)<nsw> U: [-9223372036854775766,-9223372036854775808) S: [-9223372036854775766,-9223372036854775808)
+; X64-NEXT: %in_adj_casted = bitcast i8* %in_adj to float*
+; X64-NEXT: --> (42 + %in)<nsw> U: [-9223372036854775766,-9223372036854775808) S: [-9223372036854775766,-9223372036854775808)
+; X64-NEXT: %p0 = ptrtoint float* %in_adj_casted to i64
+; X64-NEXT: --> %p0 U: full-set S: full-set
+; X64-NEXT: Determining loop execution counts for: @ptrtoint_of_bitcast_of_gep
+;
+; X32-LABEL: 'ptrtoint_of_bitcast_of_gep'
+; X32-NEXT: Classifying expressions for: @ptrtoint_of_bitcast_of_gep
+; X32-NEXT: %in_adj = getelementptr inbounds i8, i8* %in, i64 42
+; X32-NEXT: --> (42 + %in)<nsw> U: [-2147483606,-2147483648) S: [-2147483606,-2147483648)
+; X32-NEXT: %in_adj_casted = bitcast i8* %in_adj to float*
+; X32-NEXT: --> (42 + %in)<nsw> U: [-2147483606,-2147483648) S: [-2147483606,-2147483648)
+; X32-NEXT: %p0 = ptrtoint float* %in_adj_casted to i64
+; X32-NEXT: --> %p0 U: [0,4294967296) S: [-4294967296,4294967296)
+; X32-NEXT: Determining loop execution counts for: @ptrtoint_of_bitcast_of_gep
+;
+ %in_adj = getelementptr inbounds i8, i8* %in, i64 42
+ %in_adj_casted = bitcast i8* %in_adj to float*
+ %p0 = ptrtoint float* %in_adj_casted to i64
+ store i64 %p0, i64* %out0
+ ret void
+}
diff --git a/llvm/test/Analysis/ScalarEvolution/semi-transparent-inttoptr-ptrtoint-casts.ll b/llvm/test/Analysis/ScalarEvolution/semi-transparent-inttoptr-ptrtoint-casts.ll
deleted file mode 100644
index d9fdfa03d7a7..000000000000
--- a/llvm/test/Analysis/ScalarEvolution/semi-transparent-inttoptr-ptrtoint-casts.ll
+++ /dev/null
@@ -1,115 +0,0 @@
-; NOTE: Assertions have been autogenerated by utils/update_analyze_test_checks.py
-; RUN: opt < %s -S -analyze -enable-new-pm=0 -scalar-evolution | FileCheck %s
-; RUN: opt < %s -S -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck %s
-
-; While we can't treat inttoptr/ptrtoint casts as fully transparent,
-; instead of modelling them as fully opaque (unknown), we can at least model
-; their source values are opaque (unknown). Which, given e.g.:
-; %x = ???
-; %y = inttoptr %x
-; %z = inttoptr %x
-; at least allows us to tell that %y and %z are identical.
-; Note that we must stop at that, we can not further analyze %x itself.
-
-target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
-
-define dso_local void @ptrtoint(i8* %in, i64* %out0, i64* %out1, i32* %out2, i128* %out3) {
-; CHECK-LABEL: 'ptrtoint'
-; CHECK-NEXT: Classifying expressions for: @ptrtoint
-; CHECK-NEXT: %in_adj = getelementptr inbounds i8, i8* %in, i64 42
-; CHECK-NEXT: --> (42 + %in)<nsw> U: [-9223372036854775766,-9223372036854775808) S: [-9223372036854775766,-9223372036854775808)
-; CHECK-NEXT: %p0 = ptrtoint i8* %in_adj to i64
-; CHECK-NEXT: --> %p0 U: full-set S: full-set
-; CHECK-NEXT: %p1 = ptrtoint i8* %in_adj to i64
-; CHECK-NEXT: --> %p1 U: full-set S: full-set
-; CHECK-NEXT: %p2 = ptrtoint i8* %in_adj to i32
-; CHECK-NEXT: --> %p2 U: full-set S: full-set
-; CHECK-NEXT: %p3 = ptrtoint i8* %in_adj to i128
-; CHECK-NEXT: --> %p3 U: [0,18446744073709551616) S: [-18446744073709551616,18446744073709551616)
-; CHECK-NEXT: Determining loop execution counts for: @ptrtoint
-;
- %in_adj = getelementptr inbounds i8, i8* %in, i64 42
- %p0 = ptrtoint i8* %in_adj to i64
- %p1 = ptrtoint i8* %in_adj to i64
- %p2 = ptrtoint i8* %in_adj to i32
- %p3 = ptrtoint i8* %in_adj to i128
- store i64 %p0, i64* %out0
- store i64 %p1, i64* %out1
- store i32 %p2, i32* %out2
- store i128 %p3, i128* %out3
- ret void
-}
-
-define dso_local void @inttoptr(i64 %in0, i8** %out0, i8** %out1) {
-; CHECK-LABEL: 'inttoptr'
-; CHECK-NEXT: Classifying expressions for: @inttoptr
-; CHECK-NEXT: %in_adj = add i64 %in0, 42
-; CHECK-NEXT: --> (42 + %in0) U: full-set S: full-set
-; CHECK-NEXT: %i0 = inttoptr i64 %in_adj to i8*
-; CHECK-NEXT: --> %i0 U: full-set S: full-set
-; CHECK-NEXT: %i1 = inttoptr i64 %in_adj to i8*
-; CHECK-NEXT: --> %i1 U: full-set S: full-set
-; CHECK-NEXT: Determining loop execution counts for: @inttoptr
-;
- %in_adj = add i64 %in0, 42
- %i0 = inttoptr i64 %in_adj to i8*
- %i1 = inttoptr i64 %in_adj to i8*
- store i8* %i0, i8** %out0
- store i8* %i1, i8** %out1
- ret void
-}
-define dso_local void @inttoptr_widening(i32 %in1, i8** %out2) {
-; CHECK-LABEL: 'inttoptr_widening'
-; CHECK-NEXT: Classifying expressions for: @inttoptr_widening
-; CHECK-NEXT: %in_adj = add i32 %in1, 42
-; CHECK-NEXT: --> (42 + %in1) U: full-set S: full-set
-; CHECK-NEXT: %i0 = inttoptr i32 %in_adj to i8*
-; CHECK-NEXT: --> %i0 U: [0,4294967296) S: [-4294967296,4294967296)
-; CHECK-NEXT: Determining loop execution counts for: @inttoptr_widening
-;
- %in_adj = add i32 %in1, 42
- %i0 = inttoptr i32 %in_adj to i8*
- store i8* %i0, i8** %out2
- ret void
-}
-define dso_local void @inttoptr_narrowing(i128 %in2, i8** %out3) {
-; CHECK-LABEL: 'inttoptr_narrowing'
-; CHECK-NEXT: Classifying expressions for: @inttoptr_narrowing
-; CHECK-NEXT: %in_adj = add i128 %in2, 42
-; CHECK-NEXT: --> (42 + %in2) U: full-set S: full-set
-; CHECK-NEXT: %i0 = inttoptr i128 %in_adj to i8*
-; CHECK-NEXT: --> %i0 U: full-set S: full-set
-; CHECK-NEXT: Determining loop execution counts for: @inttoptr_narrowing
-;
- %in_adj = add i128 %in2, 42
- %i0 = inttoptr i128 %in_adj to i8*
- store i8* %i0, i8** %out3
- ret void
-}
-
-; Note that we never try to analyze the value of the ptrtoint/inttoptr!
-define i8* @onlysemitransparency(i8* %in) {
-; CHECK-LABEL: 'onlysemitransparency'
-; CHECK-NEXT: Classifying expressions for: @onlysemitransparency
-; CHECK-NEXT: %i0 = ptrtoint i8* %in to i64
-; CHECK-NEXT: --> %i0 U: full-set S: full-set
-; CHECK-NEXT: %i1 = inttoptr i64 %i0 to i8*
-; CHECK-NEXT: --> %i1 U: full-set S: full-set
-; CHECK-NEXT: %i2 = ptrtoint i8* %i1 to i64
-; CHECK-NEXT: --> %i2 U: full-set S: full-set
-; CHECK-NEXT: %i3 = inttoptr i64 %i2 to i8*
-; CHECK-NEXT: --> %i3 U: full-set S: full-set
-; CHECK-NEXT: %i4 = ptrtoint i8* %i3 to i64
-; CHECK-NEXT: --> %i4 U: full-set S: full-set
-; CHECK-NEXT: %i5 = inttoptr i64 %i4 to i8*
-; CHECK-NEXT: --> %i5 U: full-set S: full-set
-; CHECK-NEXT: Determining loop execution counts for: @onlysemitransparency
-;
- %i0 = ptrtoint i8* %in to i64
- %i1 = inttoptr i64 %i0 to i8*
- %i2 = ptrtoint i8* %i1 to i64
- %i3 = inttoptr i64 %i2 to i8*
- %i4 = ptrtoint i8* %i3 to i64
- %i5 = inttoptr i64 %i4 to i8*
- ret i8* %i5
-}
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