alok created this revision.
alok added reviewers: aprantl, djtodoro, jdoerfert, jini.susan.george.
alok added a project: debug-info.
Herald added subscribers: guansong, yaxunl.
alok requested review of this revision.
Herald added subscribers: cfe-commits, sstefan1.
Herald added a project: clang.
Currently variables appearing inside shared clause of OpenMP task construct are
not visible inside lldb debugger.
This is because compiler does not generate debug info for it.
* thread #1, name = 'a.out', stop reason = breakpoint 1.1
frame #0: 0x0000000000400934 a.out`.omp_task_entry. [inlined]
.omp_outlined.(.global_tid.=0, .part_id.=0x000000000071f0d0,
.privates.=0x000000000071f0e8, .copy_fn.=(a.out`.omp_task_privates_map. at
testshared.cxx:8), .task_t.=0x000000000071f0c0, __context=0x000000000071f0f0)
at testshared.cxx:10:34
7 else {
8 #pragma omp task shared(svar) firstprivate(n)
9 {
-> 10 printf("Task svar = %d\n", svar);
11 printf("Task n = %d\n", n);
12 svar = fib(n - 1);
13 }
(lldb) p svar
error: <user expression 0>:1:1: use of undeclared identifier 'svar'
svar
^
(lldb)
After the current patch, lldb is able to show the variable
* thread #1, name = 'a.out', stop reason = breakpoint 1.1
frame #0: 0x0000000000400934 a.out`.omp_task_entry. [inlined]
.omp_outlined.(.global_tid.=0, .part_id.=0x000000000071f0d0,
.privates.=0x000000000071f0e8, .copy_fn.=(a.out`.omp_task_privates_map. at
testshared.cxx:8), .task_t.=0x000000000071f0c0, __context=0x000000000071f0f0)
at testshared.cxx:10:34
7 else {
8 #pragma omp task shared(svar) firstprivate(n)
9 {
-> 10 printf("Task svar = %d\n", svar);
11 printf("Task n = %d\n", n);
12 svar = fib(n - 1);
13 }
(lldb) p svar
(int) $0 = 9
(lldb)
Repository:
rG LLVM Github Monorepo
https://reviews.llvm.org/D115510
Files:
clang/lib/CodeGen/CGStmtOpenMP.cpp
clang/lib/CodeGen/CodeGenFunction.h
clang/test/OpenMP/debug_task_shared.c
Index: clang/test/OpenMP/debug_task_shared.c
===================================================================
--- /dev/null
+++ clang/test/OpenMP/debug_task_shared.c
@@ -0,0 +1,55 @@
+// This testcase checks emission of debug info for variables
+// inside shared clause of task construct.
+
+// REQUIRES: x86_64-linux
+
+// RUN: %clang_cc1 -debug-info-kind=constructor -DSHARED -x c -verify -triple x86_64-pc-linux-gnu -fopenmp -emit-llvm %s -o - | FileCheck %s --check-prefix=CHECK
+// RUN: %clang_cc1 -debug-info-kind=constructor -x c -verify -triple x86_64-pc-linux-gnu -fopenmp -emit-llvm %s -o - | FileCheck %s --check-prefix=NEG
+// expected-no-diagnostics
+
+// CHECK-LABEL: define internal i32 @.omp_task_entry.
+
+// CHECK-DAG: [[CONTEXT:%[0-9]+]] = load %struct.anon*, %struct.anon** %__context.addr.i, align 8
+// CHECK-DAG: call void @llvm.dbg.declare(metadata %struct.anon* [[CONTEXT]], metadata [[SHARE2:![0-9]+]], metadata !DIExpression(DW_OP_deref))
+// CHECK-DAG: call void @llvm.dbg.declare(metadata %struct.anon* [[CONTEXT]], metadata [[SHARE3:![0-9]+]], metadata !DIExpression(DW_OP_plus_uconst, 8, DW_OP_deref))
+// CHECK-DAG: call void @llvm.dbg.declare(metadata %struct.anon* [[CONTEXT]], metadata [[SHARE1:![0-9]+]], metadata !DIExpression(DW_OP_plus_uconst, 16, DW_OP_deref))
+
+// CHECK-DAG: [[SHARE2]] = !DILocalVariable(name: "share2"
+// CHECK-DAG: [[SHARE3]] = !DILocalVariable(name: "share3"
+// CHECK-DAG: [[SHARE1]] = !DILocalVariable(name: "share1"
+
+// NEG-LABEL: define internal i32 @.omp_task_entry.
+// NEG: [[CONTEXT:%[0-9]+]] = load %struct.anon*, %struct.anon** %__context.addr.i, align 8
+// NEG-NOT: call void @llvm.dbg.declare(metadata %struct.anon* [[CONTEXT]], metadata {{![0-9]+}}, metadata !DIExpression(DW_OP_deref))
+
+extern int printf(const char *, ...);
+
+int foo(int n) {
+ int share1 = 9, share2 = 11, share3 = 13, priv1, priv2, fpriv;
+ fpriv = n + 4;
+
+ if (n < 2)
+ return n;
+ else {
+#if SHARED
+#pragma omp task shared(share1, share2) private(priv1, priv2) firstprivate(fpriv) shared(share3)
+#else
+#pragma omp task private(priv1, priv2) firstprivate(fpriv)
+#endif
+ {
+ priv1 = n;
+ priv2 = n + 2;
+ share2 += share3;
+ printf("share1 = %d, share2 = %d, share3 = %d\n", share1, share2, share3);
+ share1 = priv1 + priv2 + fpriv + foo(n - 1) + share2 + share3;
+ }
+#pragma omp taskwait
+ return share1 + share2 + share3;
+ }
+}
+
+int main() {
+ int n = 10;
+ printf("foo(%d) = %d\n", n, foo(n));
+ return 0;
+}
Index: clang/lib/CodeGen/CodeGenFunction.h
===================================================================
--- clang/lib/CodeGen/CodeGenFunction.h
+++ clang/lib/CodeGen/CodeGenFunction.h
@@ -459,6 +459,11 @@
/// Get the name of the capture helper.
virtual StringRef getHelperName() const { return "__captured_stmt"; }
+ /// Get the CaptureFields
+ llvm::SmallDenseMap<const VarDecl *, FieldDecl *> getCaptureFields() {
+ return CaptureFields;
+ }
+
private:
/// The kind of captured statement being generated.
CapturedRegionKind Kind;
Index: clang/lib/CodeGen/CGStmtOpenMP.cpp
===================================================================
--- clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ clang/lib/CodeGen/CGStmtOpenMP.cpp
@@ -24,10 +24,13 @@
#include "clang/AST/StmtVisitor.h"
#include "clang/Basic/OpenMPKinds.h"
#include "clang/Basic/PrettyStackTrace.h"
+#include "llvm/BinaryFormat/Dwarf.h"
#include "llvm/Frontend/OpenMP/OMPConstants.h"
#include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
#include "llvm/IR/Constants.h"
+#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Metadata.h"
#include "llvm/Support/AtomicOrdering.h"
using namespace clang;
using namespace CodeGen;
@@ -4431,6 +4434,43 @@
UntiedLocalVars;
// Set proper addresses for generated private copies.
OMPPrivateScope Scope(CGF);
+ // Generate debug info for variables present in shared clause.
+ if (auto *DI = CGF.getDebugInfo()) {
+ llvm::SmallDenseMap<const VarDecl *, FieldDecl *> CaptureFields =
+ CGF.CapturedStmtInfo->getCaptureFields();
+ llvm::Value *ContextValue = CGF.CapturedStmtInfo->getContextValue();
+ if (CaptureFields.size() && ContextValue) {
+ unsigned CharWidth = CGF.getContext().getCharWidth();
+ // Generate llvm.dbg.declare for each shared variable and
+ // DIExpression = metadata !DIExpression(DW_OP_plus_uconst, OFFSET,
+ // DW_OP_deref)
+ for (auto It = CaptureFields.begin(); It != CaptureFields.end(); ++It) {
+ const VarDecl *SharedVar = It->first;
+ RecordDecl *CaptureRecord = It->second->getParent();
+ const ASTRecordLayout &Layout =
+ CGF.getContext().getASTRecordLayout(CaptureRecord);
+ unsigned Offset =
+ Layout.getFieldOffset(It->second->getFieldIndex()) / CharWidth;
+ (void)DI->EmitDeclareOfAutoVariable(SharedVar, ContextValue,
+ CGF.Builder, false);
+ llvm::Instruction &Last = CGF.Builder.GetInsertBlock()->back();
+ // Get the call dbg.declare instruction we just created and update
+ // its DIExpression to add offset to base address.
+ if (auto DDI = dyn_cast<llvm::DbgVariableIntrinsic>(&Last)) {
+ SmallVector<uint64_t, 8> Ops;
+ // Add offset to the base address if non zero.
+ if (Offset) {
+ Ops.push_back(llvm::dwarf::DW_OP_plus_uconst);
+ Ops.push_back(Offset);
+ }
+ Ops.push_back(llvm::dwarf::DW_OP_deref);
+ auto &Ctx = DDI->getContext();
+ llvm::DIExpression *DIExpr = llvm::DIExpression::get(Ctx, Ops);
+ Last.setOperand(2, llvm::MetadataAsValue::get(Ctx, DIExpr));
+ }
+ }
+ }
+ }
llvm::SmallVector<std::pair<const VarDecl *, Address>, 16> FirstprivatePtrs;
if (!Data.PrivateVars.empty() || !Data.FirstprivateVars.empty() ||
!Data.LastprivateVars.empty() || !Data.PrivateLocals.empty()) {
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
