[flang-commits] [flang] [llvm] [mlir] [OpenMPIRBuilder] Don't drop debug info for target region. (PR #80692)
Abid Qadeer via flang-commits
flang-commits at lists.llvm.org
Tue Jul 9 07:06:03 PDT 2024
https://github.com/abidh updated https://github.com/llvm/llvm-project/pull/80692
>From 5508975815623b48068a68cb759b5c6d4aebddd9 Mon Sep 17 00:00:00 2001
From: Abid Qadeer <haqadeer at amd.com>
Date: Fri, 2 Feb 2024 12:16:52 -0600
Subject: [PATCH 1/6] [OpenMPIRBuilder] Don't drop debug info for target
region.
When an outlined function is generated for omp target region,
a corresponding DISubprogram was not being generated. This resulted in
all the debug information for the target region being dropped.
This commit adds DISubprogram for the outlined function if there is one
available for the parent function. It also updates the current debug
location so that the right scope is used for the entries in the outlined
function.
With this change in place, I can set source line breakpoint in target
region and run to them in debugger.
---
flang/test/Lower/OpenMP/target-debug.f90 | 18 ++++++++++
llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp | 36 +++++++++++++++++--
.../Frontend/OpenMPIRBuilderTest.cpp | 4 +++
3 files changed, 56 insertions(+), 2 deletions(-)
create mode 100644 flang/test/Lower/OpenMP/target-debug.f90
diff --git a/flang/test/Lower/OpenMP/target-debug.f90 b/flang/test/Lower/OpenMP/target-debug.f90
new file mode 100644
index 0000000000000..c9843eba391d7
--- /dev/null
+++ b/flang/test/Lower/OpenMP/target-debug.f90
@@ -0,0 +1,18 @@
+!RUN: %flang_fc1 -triple amdgcn-amd-amdhsa %s -debug-info-kind=line-tables-only -fopenmp -fopenmp-is-target-device -emit-llvm -o - | FileCheck %s
+program test
+implicit none
+
+ integer(kind = 4) :: a, b, c, d
+
+ !$omp target map(tofrom: a, b, c, d)
+ a = a + 1
+ ! CHECK: !DILocation(line: [[@LINE-1]]
+ b = a + 2
+ ! CHECK: !DILocation(line: [[@LINE-1]]
+ c = a + 3
+ ! CHECK: !DILocation(line: [[@LINE-1]]
+ d = a + 4
+ ! CHECK: !DILocation(line: [[@LINE-1]]
+ !$omp end target
+
+end program test
diff --git a/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp b/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
index a06e81dd280e0..7c709f86fe490 100644
--- a/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
+++ b/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
@@ -31,6 +31,7 @@
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/Constants.h"
+#include "llvm/IR/DIBuilder.h"
#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
@@ -6498,10 +6499,41 @@ static Function *createOutlinedFunction(
ParameterTypes.push_back(Arg->getType());
}
+ auto BB = Builder.GetInsertBlock();
+ auto M = BB->getModule();
auto FuncType = FunctionType::get(Builder.getVoidTy(), ParameterTypes,
/*isVarArg*/ false);
- auto Func = Function::Create(FuncType, GlobalValue::InternalLinkage, FuncName,
- Builder.GetInsertBlock()->getModule());
+ auto Func =
+ Function::Create(FuncType, GlobalValue::InternalLinkage, FuncName, M);
+
+ // If there's a DISubprogram associated with current function, then
+ // generate one for the outlined function.
+ if (Function *parentFunc = BB->getParent()) {
+ if (DISubprogram *SP = parentFunc->getSubprogram()) {
+ DICompileUnit *CU = SP->getUnit();
+ DIBuilder DB(*M, true, CU);
+ DebugLoc DL = Builder.getCurrentDebugLocation();
+ // TODO: We are using nullopt for arguments at the moment. This will need
+ // to be updated when debug data is being generated for variables.
+ DISubroutineType *Ty =
+ DB.createSubroutineType(DB.getOrCreateTypeArray(std::nullopt));
+ DISubprogram::DISPFlags SPFlags = DISubprogram::SPFlagDefinition |
+ DISubprogram::SPFlagOptimized |
+ DISubprogram::SPFlagLocalToUnit;
+
+ DISubprogram *OutlinedSP = DB.createFunction(
+ CU, FuncName, FuncName, SP->getFile(), DL.getLine(), Ty, DL.getLine(),
+ DINode::DIFlags::FlagArtificial, SPFlags);
+
+ // Attach subprogram to the function.
+ Func->setSubprogram(OutlinedSP);
+ // Update the CurrentDebugLocation in the builder so that right scope
+ // is used for things inside outlined function.
+ Builder.SetCurrentDebugLocation(
+ DILocation::get(Func->getContext(), DL.getLine(), DL.getCol(),
+ OutlinedSP, DL.getInlinedAt()));
+ }
+ }
// Save insert point.
auto OldInsertPoint = Builder.saveIP();
diff --git a/llvm/unittests/Frontend/OpenMPIRBuilderTest.cpp b/llvm/unittests/Frontend/OpenMPIRBuilderTest.cpp
index 8653bbd3d38fd..c0f4feef52556 100644
--- a/llvm/unittests/Frontend/OpenMPIRBuilderTest.cpp
+++ b/llvm/unittests/Frontend/OpenMPIRBuilderTest.cpp
@@ -6006,6 +6006,10 @@ TEST_F(OpenMPIRBuilderTest, TargetRegion) {
BasicBlock *FallbackBlock = Branch->getSuccessor(0);
Iter = FallbackBlock->rbegin();
CallInst *FCall = dyn_cast<CallInst>(&*(++Iter));
+ // 'F' has a dummy DISubprogram which causes OutlinedFunc to also
+ // have a DISubprogram. In this case, the call to OutlinedFunc needs
+ // to have a debug loc, otherwise verifier will complain.
+ FCall->setDebugLoc(DL);
EXPECT_NE(FCall, nullptr);
// Check that the correct aguments are passed in
>From e5cfb7dccbf87ae79aa053b5811a2fbd5811ec35 Mon Sep 17 00:00:00 2001
From: Abid Qadeer <haqadeer at amd.com>
Date: Wed, 7 Feb 2024 10:07:11 -0600
Subject: [PATCH 2/6] Move the test into MLIR.
The original f90 ->llvmir test has been removed.
I have added an MLIR -> llvmir test as per review comments.
---
flang/test/Lower/OpenMP/target-debug.f90 | 18 -----
mlir/test/Target/LLVMIR/omptarget-debug.mlir | 72 ++++++++++++++++++++
2 files changed, 72 insertions(+), 18 deletions(-)
delete mode 100644 flang/test/Lower/OpenMP/target-debug.f90
create mode 100644 mlir/test/Target/LLVMIR/omptarget-debug.mlir
diff --git a/flang/test/Lower/OpenMP/target-debug.f90 b/flang/test/Lower/OpenMP/target-debug.f90
deleted file mode 100644
index c9843eba391d7..0000000000000
--- a/flang/test/Lower/OpenMP/target-debug.f90
+++ /dev/null
@@ -1,18 +0,0 @@
-!RUN: %flang_fc1 -triple amdgcn-amd-amdhsa %s -debug-info-kind=line-tables-only -fopenmp -fopenmp-is-target-device -emit-llvm -o - | FileCheck %s
-program test
-implicit none
-
- integer(kind = 4) :: a, b, c, d
-
- !$omp target map(tofrom: a, b, c, d)
- a = a + 1
- ! CHECK: !DILocation(line: [[@LINE-1]]
- b = a + 2
- ! CHECK: !DILocation(line: [[@LINE-1]]
- c = a + 3
- ! CHECK: !DILocation(line: [[@LINE-1]]
- d = a + 4
- ! CHECK: !DILocation(line: [[@LINE-1]]
- !$omp end target
-
-end program test
diff --git a/mlir/test/Target/LLVMIR/omptarget-debug.mlir b/mlir/test/Target/LLVMIR/omptarget-debug.mlir
new file mode 100644
index 0000000000000..4d061eb25082b
--- /dev/null
+++ b/mlir/test/Target/LLVMIR/omptarget-debug.mlir
@@ -0,0 +1,72 @@
+// RUN: mlir-translate -mlir-to-llvmir %s | FileCheck %s
+
+module attributes {omp.is_target_device = true} {
+ llvm.func @_QQmain() {
+ %0 = llvm.mlir.constant(1 : i64) : i64
+ %1 = llvm.alloca %0 x i32 : (i64) -> !llvm.ptr<5>
+ %2 = llvm.addrspacecast %1 : !llvm.ptr<5> to !llvm.ptr
+ %3 = llvm.mlir.constant(1 : i64) : i64
+ %4 = llvm.alloca %3 x i32 : (i64) -> !llvm.ptr<5>
+ %5 = llvm.addrspacecast %4 : !llvm.ptr<5> to !llvm.ptr
+ %6 = llvm.mlir.constant(1 : i64) : i64
+ %7 = llvm.alloca %6 x i32 : (i64) -> !llvm.ptr<5>
+ %8 = llvm.addrspacecast %7 : !llvm.ptr<5> to !llvm.ptr
+ %9 = omp.map_info var_ptr(%2 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
+ %10 = omp.map_info var_ptr(%5 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
+ omp.target map_entries(%9 -> %arg0, %10 -> %arg1 : !llvm.ptr, !llvm.ptr) {
+ ^bb0(%arg0: !llvm.ptr, %arg1: !llvm.ptr):
+ %12 = llvm.mlir.constant(2 : i32) : i32
+ %13 = llvm.mlir.constant(1 : i32) : i32
+ %14 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc2)
+ %15 = llvm.add %14, %13 : i32 loc(#loc2)
+ llvm.store %15, %arg0 : i32, !llvm.ptr loc(#loc2)
+ %16 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc3)
+ %17 = llvm.add %16, %12 : i32 loc(#loc3)
+ llvm.store %17, %arg1 : i32, !llvm.ptr loc(#loc3)
+ omp.terminator
+ }
+ %11 = omp.map_info var_ptr(%8 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
+ omp.target map_entries(%11 -> %arg0 : !llvm.ptr) {
+ ^bb0(%arg0: !llvm.ptr):
+ %12 = llvm.mlir.constant(1 : i32) : i32
+ omp.parallel {
+ %13 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc4)
+ %14 = llvm.add %13, %12 : i32 loc(#loc4)
+ llvm.store %14, %arg0 : i32, !llvm.ptr loc(#loc4)
+ omp.terminator
+ }
+ omp.terminator
+ }
+ llvm.return
+ } loc(#loc5)
+} loc(#loc)
+#di_basic_type = #llvm.di_basic_type<tag = DW_TAG_base_type, name = "void", encoding = DW_ATE_address>
+#di_file = #llvm.di_file<"target.f90" in "">
+#loc = loc("target.f90":0:0)
+#loc1 = loc("target.f90":1:1)
+#loc2 = loc("target.f90":9:3)
+#loc3 = loc("target.f90":10:3)
+#loc4 = loc("target.f90":14:3)
+#di_compile_unit = #llvm.di_compile_unit<id = distinct[0]<>, sourceLanguage = DW_LANG_Fortran95, file = #di_file, producer = "Flang", isOptimized = false, emissionKind = LineTablesOnly>
+#di_subroutine_type = #llvm.di_subroutine_type<callingConvention = DW_CC_normal, types = #di_basic_type, #di_basic_type>
+#di_subprogram = #llvm.di_subprogram<id = distinct[1]<>, compileUnit = #di_compile_unit, scope = #di_file, name = "_QQmain", linkageName = "_QQmain", file = #di_file, line = 1, scopeLine = 1, subprogramFlags = "Definition|Optimized", type = #di_subroutine_type>
+#loc5 = loc(fused<#di_subprogram>[#loc1])
+
+// 8: !$omp target map(tofrom: a, b)
+// 9: a = a + 1
+//10: b = a + 2
+//11: !$omp end target
+
+//13: !$omp target parallel map(tofrom: a, b)
+//14: c = c + 1
+//15: !$omp end target parallel
+
+// CHECK-DAG: [[FILE:.*]] = !DIFile(filename: "target.f90", directory: "")
+// CHECK-DAG: [[CU:.*]] = distinct !DICompileUnit(language: DW_LANG_Fortran95, file: [[FILE]], {{.*}})
+
+// CHECK: [[SP1:.*]] = distinct !DISubprogram(name: "__omp_offloading_{{.*}}", {{.*}}, unit: [[CU]])
+// CHECK-DAG: !DILocation(line: 9, column: 3, scope: [[SP1]])
+// CHECK-DAG: !DILocation(line: 10, column: 3, scope: [[SP1]])
+
+// CHECK: [[SP2:.*]] = distinct !DISubprogram(name: "__omp_offloading_{{.*}}omp_par", {{.*}}, unit: [[CU]])
+// CHECK: !DILocation(line: 14, column: 3, scope: [[SP2]])
>From 450e7cac6472aaf0e576bb4374a53571d17a14c4 Mon Sep 17 00:00:00 2001
From: Abid Qadeer <haqadeer at amd.com>
Date: Wed, 7 Feb 2024 10:08:08 -0600
Subject: [PATCH 3/6] Correct the case on variable name.
---
llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp b/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
index 7c709f86fe490..9a04a58244477 100644
--- a/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
+++ b/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
@@ -6508,8 +6508,8 @@ static Function *createOutlinedFunction(
// If there's a DISubprogram associated with current function, then
// generate one for the outlined function.
- if (Function *parentFunc = BB->getParent()) {
- if (DISubprogram *SP = parentFunc->getSubprogram()) {
+ if (Function *ParentFunc = BB->getParent()) {
+ if (DISubprogram *SP = ParentFunc->getSubprogram()) {
DICompileUnit *CU = SP->getUnit();
DIBuilder DB(*M, true, CU);
DebugLoc DL = Builder.getCurrentDebugLocation();
>From ac4709814f51aa02ced9a5d3151ad5c16436ef46 Mon Sep 17 00:00:00 2001
From: Abid Qadeer <haqadeer at amd.com>
Date: Mon, 8 Jul 2024 16:22:20 +0100
Subject: [PATCH 4/6] Minimize testcase as per review comments.
---
mlir/test/Target/LLVMIR/omptarget-debug.mlir | 57 ++++----------------
1 file changed, 10 insertions(+), 47 deletions(-)
diff --git a/mlir/test/Target/LLVMIR/omptarget-debug.mlir b/mlir/test/Target/LLVMIR/omptarget-debug.mlir
index 4d061eb25082b..824df55704a6c 100644
--- a/mlir/test/Target/LLVMIR/omptarget-debug.mlir
+++ b/mlir/test/Target/LLVMIR/omptarget-debug.mlir
@@ -5,68 +5,31 @@ module attributes {omp.is_target_device = true} {
%0 = llvm.mlir.constant(1 : i64) : i64
%1 = llvm.alloca %0 x i32 : (i64) -> !llvm.ptr<5>
%2 = llvm.addrspacecast %1 : !llvm.ptr<5> to !llvm.ptr
- %3 = llvm.mlir.constant(1 : i64) : i64
- %4 = llvm.alloca %3 x i32 : (i64) -> !llvm.ptr<5>
- %5 = llvm.addrspacecast %4 : !llvm.ptr<5> to !llvm.ptr
- %6 = llvm.mlir.constant(1 : i64) : i64
- %7 = llvm.alloca %6 x i32 : (i64) -> !llvm.ptr<5>
- %8 = llvm.addrspacecast %7 : !llvm.ptr<5> to !llvm.ptr
- %9 = omp.map_info var_ptr(%2 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
- %10 = omp.map_info var_ptr(%5 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
- omp.target map_entries(%9 -> %arg0, %10 -> %arg1 : !llvm.ptr, !llvm.ptr) {
+ %9 = omp.map.info var_ptr(%2 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
+ omp.target map_entries(%9 -> %arg0 : !llvm.ptr) {
^bb0(%arg0: !llvm.ptr, %arg1: !llvm.ptr):
- %12 = llvm.mlir.constant(2 : i32) : i32
%13 = llvm.mlir.constant(1 : i32) : i32
%14 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc2)
%15 = llvm.add %14, %13 : i32 loc(#loc2)
llvm.store %15, %arg0 : i32, !llvm.ptr loc(#loc2)
- %16 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc3)
- %17 = llvm.add %16, %12 : i32 loc(#loc3)
- llvm.store %17, %arg1 : i32, !llvm.ptr loc(#loc3)
- omp.terminator
- }
- %11 = omp.map_info var_ptr(%8 : !llvm.ptr, i32) map_clauses(tofrom) capture(ByRef) -> !llvm.ptr {name = ""}
- omp.target map_entries(%11 -> %arg0 : !llvm.ptr) {
- ^bb0(%arg0: !llvm.ptr):
- %12 = llvm.mlir.constant(1 : i32) : i32
- omp.parallel {
- %13 = llvm.load %arg0 : !llvm.ptr -> i32 loc(#loc4)
- %14 = llvm.add %13, %12 : i32 loc(#loc4)
- llvm.store %14, %arg0 : i32, !llvm.ptr loc(#loc4)
- omp.terminator
- }
omp.terminator
}
llvm.return
} loc(#loc5)
-} loc(#loc)
+}
#di_basic_type = #llvm.di_basic_type<tag = DW_TAG_base_type, name = "void", encoding = DW_ATE_address>
#di_file = #llvm.di_file<"target.f90" in "">
-#loc = loc("target.f90":0:0)
#loc1 = loc("target.f90":1:1)
-#loc2 = loc("target.f90":9:3)
-#loc3 = loc("target.f90":10:3)
-#loc4 = loc("target.f90":14:3)
+#loc2 = loc("target.f90":46:3)
+
#di_compile_unit = #llvm.di_compile_unit<id = distinct[0]<>, sourceLanguage = DW_LANG_Fortran95, file = #di_file, producer = "Flang", isOptimized = false, emissionKind = LineTablesOnly>
#di_subroutine_type = #llvm.di_subroutine_type<callingConvention = DW_CC_normal, types = #di_basic_type, #di_basic_type>
#di_subprogram = #llvm.di_subprogram<id = distinct[1]<>, compileUnit = #di_compile_unit, scope = #di_file, name = "_QQmain", linkageName = "_QQmain", file = #di_file, line = 1, scopeLine = 1, subprogramFlags = "Definition|Optimized", type = #di_subroutine_type>
#loc5 = loc(fused<#di_subprogram>[#loc1])
-// 8: !$omp target map(tofrom: a, b)
-// 9: a = a + 1
-//10: b = a + 2
-//11: !$omp end target
-
-//13: !$omp target parallel map(tofrom: a, b)
-//14: c = c + 1
-//15: !$omp end target parallel
-
-// CHECK-DAG: [[FILE:.*]] = !DIFile(filename: "target.f90", directory: "")
-// CHECK-DAG: [[CU:.*]] = distinct !DICompileUnit(language: DW_LANG_Fortran95, file: [[FILE]], {{.*}})
-
-// CHECK: [[SP1:.*]] = distinct !DISubprogram(name: "__omp_offloading_{{.*}}", {{.*}}, unit: [[CU]])
-// CHECK-DAG: !DILocation(line: 9, column: 3, scope: [[SP1]])
-// CHECK-DAG: !DILocation(line: 10, column: 3, scope: [[SP1]])
+// 45: !$omp target map(tofrom: a)
+// 46: a = a + 1
+// 47: !$omp end target
-// CHECK: [[SP2:.*]] = distinct !DISubprogram(name: "__omp_offloading_{{.*}}omp_par", {{.*}}, unit: [[CU]])
-// CHECK: !DILocation(line: 14, column: 3, scope: [[SP2]])
+// CHECK: [[SP:.*]] = distinct !DISubprogram(name: "__omp_offloading_{{.*}}"{{.*}})
+// CHECK-DAG: !DILocation(line: 46, column: 3, scope: [[SP]])
>From 3450d4b075f6aba11b332a48123caf5c098c7326 Mon Sep 17 00:00:00 2001
From: Abid Qadeer <haqadeer at amd.com>
Date: Tue, 9 Jul 2024 13:53:19 +0100
Subject: [PATCH 5/6] Don't generate debug info for variable in target region.
These variables currently fail the llvm verifier tests as the scope
inside the variable is still point to the parent function of the
target region.
---
flang/lib/Optimizer/Transforms/AddDebugInfo.cpp | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/flang/lib/Optimizer/Transforms/AddDebugInfo.cpp b/flang/lib/Optimizer/Transforms/AddDebugInfo.cpp
index 10c71d3fc9551..025d3c39061a6 100644
--- a/flang/lib/Optimizer/Transforms/AddDebugInfo.cpp
+++ b/flang/lib/Optimizer/Transforms/AddDebugInfo.cpp
@@ -103,7 +103,11 @@ void AddDebugInfoPass::handleDeclareOp(fir::cg::XDeclareOp declOp,
if (fir::isDummyArgument(declOp.getMemref())) {
auto arg = llvm::cast<mlir::BlockArgument>(declOp.getMemref());
argNo = arg.getArgNumber() + 1;
- }
+ } else if (llvm::isa<mlir::BlockArgument>(declOp.getMemref()))
+ // FIXME: Handle arguments which are not dummy. These may be arguments
+ // to things like OpenMP regions. They may need some extra processing
+ // (e.g. to set the scope correctly).
+ return;
auto tyAttr = typeGen.convertType(fir::unwrapRefType(declOp.getType()),
fileAttr, scopeAttr, declOp.getLoc());
>From a6eea444caab2b86078174f4a89f63a8e97dedb1 Mon Sep 17 00:00:00 2001
From: Abid Qadeer <haqadeer at amd.com>
Date: Tue, 9 Jul 2024 15:04:55 +0100
Subject: [PATCH 6/6] Fix clang-format issues.
---
llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp b/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
index 9a04a58244477..52f88c917d535 100644
--- a/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
+++ b/llvm/lib/Frontend/OpenMP/OMPIRBuilder.cpp
@@ -40,8 +40,8 @@
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Metadata.h"
-#include "llvm/IR/PassManager.h"
#include "llvm/IR/PassInstrumentation.h"
+#include "llvm/IR/PassManager.h"
#include "llvm/IR/ReplaceConstant.h"
#include "llvm/IR/Value.h"
#include "llvm/MC/TargetRegistry.h"
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