[C-API][DIBuilder] Added DIFlags in LLVMDIBuilderCreateBasicType

[Chirag]

Summary

Added DIFlags in LLVMDIBuilderCreateBasicType to add optional DWARF attributes, such as DW_AT_endianity.

[Chirag]

This change will support to add optional dwarf attributes to tag_base_type entries.
At the moment only DW_AT_endianity is supported. which is useful for bi-endian code generation such as scaler-storage-order extension in gcc

This is an extension to commit https://reviews.llvm.org/rL339714

[Chirag]

• minor format fixes.

[Chirag]

Hello whitequark.

Thanks for fast response.
I do not have write access to repo, can you kindly push this changes?

Regards,

[Chirag]

• fixed mistake with go.

[Chirag]

bindings/go/llvm/dibuilder.go

func (d *DIBuilder) CreateBasicType(t DIBasicType) Metadata {
   name := C.CString(t.Name)
   defer C.free(unsafe.Pointer(name))
   result := C.LLVMDIBuilderCreateBasicType(
     d.ref,
     name,
     C.size_t(len(t.Name)),
     C.uint64_t(t.SizeInBits),
     C.unsigned(t.Encoding),
+    C.LLVMDIFlags(0),
   )
   return Metadata{C: result}
 }
 
 // DIPointerType holds the values for creating pointer type debug metadata.
 type DIPointerType struct {
   Pointee     Metadata
   SizeInBits  uint64

include/llvm-c/DebugInfo.h

typedef enum {
   LLVMDIFlagBitField = 1 << 19,
   LLVMDIFlagNoReturn = 1 << 20,
   LLVMDIFlagMainSubprogram = 1 << 21,
   LLVMDIFlagTypePassByValue = 1 << 22,
   LLVMDIFlagTypePassByReference = 1 << 23,
   LLVMDIFlagFixedEnum = 1 << 24,
   LLVMDIFlagThunk = 1 << 25,
   LLVMDIFlagTrivial = 1 << 26,
+  LLVMDIFlagBigEndian = (1 << 27),
+  LLVMDIFlagLittleEndian = (1 << 28),
   LLVMDIFlagIndirectVirtualBase = (1 << 2) | (1 << 5),
   LLVMDIFlagAccessibility = LLVMDIFlagPrivate | LLVMDIFlagProtected |
                             LLVMDIFlagPublic,
   LLVMDIFlagPtrToMemberRep = LLVMDIFlagSingleInheritance |
                              LLVMDIFlagMultipleInheritance |
                              LLVMDIFlagVirtualInheritance
 } LLVMDIFlags;
 

 /**
  * Create debugging information entry for a basic
  * type.
  * \param Builder     The DIBuilder.
  * \param Name        Type name.
  * \param NameLen     Length of type name.
  * \param SizeInBits  Size of the type.
  * \param Encoding    DWARF encoding code, e.g. \c LLVMDWARFTypeEncoding_float.
+ * \param Flags       Flags to encode optional attribute like endianity
  */
 LLVMMetadataRef
 LLVMDIBuilderCreateBasicType(LLVMDIBuilderRef Builder, const char *Name,
                              size_t NameLen, uint64_t SizeInBits,
-                             LLVMDWARFTypeEncoding Encoding);
+                             LLVMDWARFTypeEncoding Encoding,
+                             LLVMDIFlags Flags);
 
 /**
  * Create debugging information entry for a pointer.
  * \param Builder     The DIBuilder.
  * \param PointeeTy         Type pointed by this pointer.
  * \param SizeInBits        Size.
  * \param AlignInBits       Alignment. (optional, pass 0 to ignore)
  * \param AddressSpace      DWARF address space. (optional, pass 0 to ignore)

lib/IR/DebugInfo.cpp

auto Subs = unwrap(Builder)->getOrCreateArray({unwrap(Subscripts),
                                                  NumSubscripts});
   return wrap(unwrap(Builder)->createVectorType(Size, AlignInBits,
                                                 unwrapDI<DIType>(Ty), Subs));
 }
 
 LLVMMetadataRef
 LLVMDIBuilderCreateBasicType(LLVMDIBuilderRef Builder, const char *Name,
                              size_t NameLen, uint64_t SizeInBits,
-                             LLVMDWARFTypeEncoding Encoding) {
+                             LLVMDWARFTypeEncoding Encoding,
+                             LLVMDIFlags Flags) {
   return wrap(unwrap(Builder)->createBasicType({Name, NameLen},
-                                               SizeInBits, Encoding));
+                                               SizeInBits, Encoding,
+                                               map_from_llvmDIFlags(Flags)));
 }
 
 LLVMMetadataRef LLVMDIBuilderCreatePointerType(
     LLVMDIBuilderRef Builder, LLVMMetadataRef PointeeTy,
     uint64_t SizeInBits, uint32_t AlignInBits, unsigned AddressSpace,
     const char *Name, size_t NameLen) {
   return wrap(unwrap(Builder)->createPointerType(unwrapDI<DIType>(PointeeTy),
                                          SizeInBits, AlignInBits,

tools/llvm-c-test/debuginfo.c

int llvm_test_dibuilder(void) {
   LLVMMetadataRef GlobalClassValueExpr =
     LLVMDIBuilderCreateConstantValueExpression(DIB, 0);
   LLVMDIBuilderCreateGlobalVariableExpression(DIB, Module, "globalClass", 11,
                                               "", 0, File, 1, ClassTy,
                                               true, GlobalClassValueExpr,
                                               NULL, 0);
 
   LLVMMetadataRef Int64Ty =
-    LLVMDIBuilderCreateBasicType(DIB, "Int64", 5, 64, 0);
+    LLVMDIBuilderCreateBasicType(DIB, "Int64", 5, 64, 0, LLVMDIFlagZero);
   LLVMMetadataRef Int64TypeDef =
     LLVMDIBuilderCreateTypedef(DIB, Int64Ty, "int64_t", 7, File, 42, File);
 
   LLVMMetadataRef GlobalVarValueExpr =
     LLVMDIBuilderCreateConstantValueExpression(DIB, 0);
   LLVMDIBuilderCreateGlobalVariableExpression(DIB, Module, "global", 6,
                                               "", 0, File, 1, Int64TypeDef,
                                               true, GlobalVarValueExpr,