[clang] [llvm] [Hexagon] ELF attributes for Hexagon (PR #85359)

[Fangrui Song via llvm-commits]

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@@ -652,6 +660,57 @@ bool HexagonAsmParser::MatchAndEmitInstruction(SMLoc IDLoc, unsigned &Opcode,
     return finishBundle(IDLoc, Out);
   return false;
 }
+/// parseDirectiveAttribute
+///  ::= .attribute int, int
+///  ::= .attribute Tag_name, int
+bool HexagonAsmParser::parseDirectiveAttribute(SMLoc L) {
+  MCAsmParser &Parser = getParser();
+  int64_t Tag;
+  SMLoc TagLoc = Parser.getTok().getLoc();
+  if (Parser.getTok().is(AsmToken::Identifier)) {
+    StringRef Name = Parser.getTok().getIdentifier();
+    std::optional<unsigned> Ret = ELFAttrs::attrTypeFromString(
+        Name, HexagonAttrs::getHexagonAttributeTags());
+    if (!Ret)
+      return Error(TagLoc, "attribute name not recognized: " + Name);
+    Tag = *Ret;
+    Parser.Lex();
+  } else {
+    const MCExpr *AttrExpr;
+
+    TagLoc = Parser.getTok().getLoc();
+    if (Parser.parseExpression(AttrExpr))
+      return true;
+
+    const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(AttrExpr);
+    if (check(!CE, TagLoc, "expected numeric constant"))
+      return true;
+
+    Tag = CE->getValue();
+  }
+
+  if (Parser.parseComma())
+    return true;
+
+  // We currently only have integer values.
+  int64_t IntegerValue = 0;
+  SMLoc ValueExprLoc = Parser.getTok().getLoc();
+  const MCExpr *ValueExpr;
+  if (Parser.parseExpression(ValueExpr))
+    return true;
+
+  const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(ValueExpr);
+  if (!CE)
+    return Error(ValueExprLoc, "expected numeric constant");
+  IntegerValue = CE->getValue();
+
+  if (Parser.parseEOL())
+    return true;
+
+  getTargetStreamer().emitAttribute(Tag, IntegerValue);
+
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MaskRay wrote:

unneeded blank line

https://github.com/llvm/llvm-project/pull/85359