Add overload of DIBuilder::createArrayType

[tromey]

DICompositeType has an attribute representing the name of a type, but currently it isn't possible to set this for array types via the DIBuilder method. This patch adds a new overload of DIBuilder::createArrayType that allows "full" construction of an array type. This is useful for Ada, where arrays are a bit more first-class than C.

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[llvmbot]

@llvm/pr-subscribers-llvm-ir

Author: Tom Tromey (tromey)

Changes

DICompositeType has an attribute representing the name of a type, but currently it isn't possible to set this for array types via the DIBuilder method. This patch adds a new overload of DIBuilder::createArrayType that allows "full" construction of an array type. This is useful for Ada, where arrays are a bit more first-class than C.

---

Full diff: https://github.com/llvm/llvm-project/pull/125229.diff

3 Files Affected:

• (modified) llvm/include/llvm/IR/DIBuilder.h (+29)
• (modified) llvm/lib/IR/DIBuilder.cpp (+23)
• (modified) llvm/unittests/IR/DebugInfoTest.cpp (+6)

diff --git a/llvm/include/llvm/IR/DIBuilder.h b/llvm/include/llvm/IR/DIBuilder.h
index 6c479415b9ed27..c587cc61d83ca3 100644
--- a/llvm/include/llvm/IR/DIBuilder.h
+++ b/llvm/include/llvm/IR/DIBuilder.h
@@ -606,6 +606,35 @@ namespace llvm {
         PointerUnion<DIExpression *, DIVariable *> Allocated = nullptr,
         PointerUnion<DIExpression *, DIVariable *> Rank = nullptr);
 
+    /// Create debugging information entry for an array.
+    /// \param Scope          Scope in which this enumeration is defined.
+    /// \param Name           Union name.
+    /// \param File           File where this member is defined.
+    /// \param LineNumber     Line number.
+    /// \param Size         Array size.
+    /// \param AlignInBits  Alignment.
+    /// \param Ty           Element type.
+    /// \param Subscripts   Subscripts.
+    /// \param DataLocation The location of the raw data of a descriptor-based
+    ///                     Fortran array, either a DIExpression* or
+    ///                     a DIVariable*.
+    /// \param Associated   The associated attribute of a descriptor-based
+    ///                     Fortran array, either a DIExpression* or
+    ///                     a DIVariable*.
+    /// \param Allocated    The allocated attribute of a descriptor-based
+    ///                     Fortran array, either a DIExpression* or
+    ///                     a DIVariable*.
+    /// \param Rank         The rank attribute of a descriptor-based
+    ///                     Fortran array, either a DIExpression* or
+    ///                     a DIVariable*.
+    DICompositeType *createArrayType(
+        DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
+        uint64_t Size, uint32_t AlignInBits, DIType *Ty, DINodeArray Subscripts,
+        PointerUnion<DIExpression *, DIVariable *> DataLocation = nullptr,
+        PointerUnion<DIExpression *, DIVariable *> Associated = nullptr,
+        PointerUnion<DIExpression *, DIVariable *> Allocated = nullptr,
+        PointerUnion<DIExpression *, DIVariable *> Rank = nullptr);
+
     /// Create debugging information entry for a vector type.
     /// \param Size         Array size.
     /// \param AlignInBits  Alignment.
diff --git a/llvm/lib/IR/DIBuilder.cpp b/llvm/lib/IR/DIBuilder.cpp
index 8f9462ab46d885..6b3e3c5c5eea9f 100644
--- a/llvm/lib/IR/DIBuilder.cpp
+++ b/llvm/lib/IR/DIBuilder.cpp
@@ -616,6 +616,29 @@ DIBuilder::createArrayType(uint64_t Size, uint32_t AlignInBits, DIType *Ty,
   return R;
 }
 
+DICompositeType *DIBuilder::createArrayType(
+    DIScope *Scope, StringRef Name, DIFile *File, unsigned LineNumber,
+    uint64_t Size, uint32_t AlignInBits, DIType *Ty, DINodeArray Subscripts,
+    PointerUnion<DIExpression *, DIVariable *> DL,
+    PointerUnion<DIExpression *, DIVariable *> AS,
+    PointerUnion<DIExpression *, DIVariable *> AL,
+    PointerUnion<DIExpression *, DIVariable *> RK) {
+  auto *R = DICompositeType::get(
+      VMContext, dwarf::DW_TAG_array_type, Name, File, LineNumber,
+      getNonCompileUnitScope(Scope), Ty, Size, AlignInBits, 0, DINode::FlagZero,
+      Subscripts, 0, nullptr, nullptr, "", nullptr,
+      isa<DIExpression *>(DL) ? (Metadata *)cast<DIExpression *>(DL)
+                              : (Metadata *)cast<DIVariable *>(DL),
+      isa<DIExpression *>(AS) ? (Metadata *)cast<DIExpression *>(AS)
+                              : (Metadata *)cast<DIVariable *>(AS),
+      isa<DIExpression *>(AL) ? (Metadata *)cast<DIExpression *>(AL)
+                              : (Metadata *)cast<DIVariable *>(AL),
+      isa<DIExpression *>(RK) ? (Metadata *)cast<DIExpression *>(RK)
+                              : (Metadata *)cast<DIVariable *>(RK));
+  trackIfUnresolved(R);
+  return R;
+}
+
 DICompositeType *DIBuilder::createVectorType(uint64_t Size,
                                              uint32_t AlignInBits, DIType *Ty,
                                              DINodeArray Subscripts) {
diff --git a/llvm/unittests/IR/DebugInfoTest.cpp b/llvm/unittests/IR/DebugInfoTest.cpp
index 4283ba7a8f8236..c632bd6d3cbb54 100644
--- a/llvm/unittests/IR/DebugInfoTest.cpp
+++ b/llvm/unittests/IR/DebugInfoTest.cpp
@@ -1270,6 +1270,12 @@ TEST(DIBuilder, CompositeTypes) {
   DICompositeType *Array = DIB.createArrayType(8, 8, nullptr, {});
   EXPECT_EQ(Array->getTag(), dwarf::DW_TAG_array_type);
 
+  StringRef ArrayNameExp = "AnArray";
+  DICompositeType *NamedArray =
+      DIB.createArrayType(nullptr, ArrayNameExp, nullptr, 0, 8, 8, nullptr, {});
+  EXPECT_EQ(NamedArray->getTag(), dwarf::DW_TAG_array_type);
+  EXPECT_EQ(NamedArray->getName(), ArrayNameExp);
+
   DICompositeType *Vector = DIB.createVectorType(8, 8, nullptr, {});
   EXPECT_EQ(Vector->getTag(), dwarf::DW_TAG_array_type);
 

[tromey]

I do not think those failures could possibly come from this patch...?

[tromey]

I rebased this; it needed one minor change to still compile.

[tromey]

@dwblaikie I looked in llvm/Maintainers.md and you were listed in the "Debug info and DWARF" with the note "especially type information", so I'm taking the liberty of CCing you.

The bot didn't add the "debuginfo" tag to this patch for whatever reason.

[dwblaikie]

(if necessary (perhaps it falls out naturally from the implementation already, but I wouldn't assume so) I guess you'll send a separate patch to actually emit this name in llvm/lib/CodeGen/AsmPrinter/Dwarf*?)

[tromey]

(if necessary (perhaps it falls out naturally from the implementation already, but I wouldn't assume so) I guess you'll send a separate patch to actually emit this name in llvm/lib/CodeGen/AsmPrinter/Dwarf*?)

This already works because DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) handles the name generically: https://github.com/llvm/llvm-project/blob/main/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp#L1071-L1073

[github-actions]

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