Add support for fixed-point types (#129596)

This adds DWARF generation for fixed-point types. This feature is needed
by Ada.

Note that a pre-existing GNU extension is used in one case. This has
been emitted by GCC for years, and is needed because standard DWARF is
otherwise incapable of representing these types.

1 files changed, 32 insertions, 0 deletions

diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index 4941109..4a0db9d 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -323,6 +323,9 @@ private:
                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
   void writeDIBasicType(const DIBasicType *N, SmallVectorImpl<uint64_t> &Record,
                         unsigned Abbrev);
+  void writeDIFixedPointType(const DIFixedPointType *N,
+                             SmallVectorImpl<uint64_t> &Record,
+                             unsigned Abbrev);
   void writeDIStringType(const DIStringType *N,
                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
   void writeDIDerivedType(const DIDerivedType *N,
@@ -1887,6 +1890,35 @@ void ModuleBitcodeWriter::writeDIBasicType(const DIBasicType *N,
   Record.clear();
 }
 
+void ModuleBitcodeWriter::writeDIFixedPointType(
+    const DIFixedPointType *N, SmallVectorImpl<uint64_t> &Record,
+    unsigned Abbrev) {
+  Record.push_back(N->isDistinct());
+  Record.push_back(N->getTag());
+  Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
+  Record.push_back(N->getSizeInBits());
+  Record.push_back(N->getAlignInBits());
+  Record.push_back(N->getEncoding());
+  Record.push_back(N->getFlags());
+  Record.push_back(N->getKind());
+  Record.push_back(N->getFactorRaw());
+
+  auto WriteWideInt = [&](const APInt &Value) {
+    // Write an encoded word that holds the number of active words and
+    // the number of bits.
+    uint64_t NumWords = Value.getActiveWords();
+    uint64_t Encoded = (NumWords << 32) | Value.getBitWidth();
+    Record.push_back(Encoded);
+    emitWideAPInt(Record, Value);
+  };
+
+  WriteWideInt(N->getNumeratorRaw());
+  WriteWideInt(N->getDenominatorRaw());
+
+  Stream.EmitRecord(bitc::METADATA_FIXED_POINT_TYPE, Record, Abbrev);
+  Record.clear();
+}
+
 void ModuleBitcodeWriter::writeDIStringType(const DIStringType *N,
                                             SmallVectorImpl<uint64_t> &Record,
                                             unsigned Abbrev) {