[llvm] [RISCV] Improvements to .note.gnu.property section. (PR #151436)

[Fangrui Song via llvm-commits]

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@@ -83,29 +86,21 @@ void RISCVTargetStreamer::emitNoteGnuPropertySection(
   OutStreamer.switchSection(NoteSection);
 
   // Emit the note header
-  OutStreamer.emitIntValue(4, 4); // n_namsz
-
-  MCSymbol *const NDescBeginSym = Ctx.createTempSymbol();
-  MCSymbol *const NDescEndSym = Ctx.createTempSymbol();
-  const MCExpr *const NDescSzExpr =
-      MCBinaryExpr::createSub(MCSymbolRefExpr::create(NDescEndSym, Ctx),
-                              MCSymbolRefExpr::create(NDescBeginSym, Ctx), Ctx);
-
-  OutStreamer.emitValue(NDescSzExpr, 4);                    // n_descsz
+  OutStreamer.emitValueToAlignment(NoteAlign);
+  OutStreamer.emitIntValue(4, 4);                           // n_namsz
+  OutStreamer.emitIntValue(DescSize, 4);                    // n_descsz
   OutStreamer.emitIntValue(ELF::NT_GNU_PROPERTY_TYPE_0, 4); // n_type
   OutStreamer.emitBytes(StringRef("GNU", 4));               // n_name
 
   // Emit n_desc field
-  OutStreamer.emitLabel(NDescBeginSym);
-  OutStreamer.emitValueToAlignment(NoteAlign);
 
   // Emit the feature_1_and property
   OutStreamer.emitIntValue(ELF::GNU_PROPERTY_RISCV_FEATURE_1_AND, 4); // pr_type
   OutStreamer.emitIntValue(4, 4);              // pr_datasz
   OutStreamer.emitIntValue(Feature1And, 4);    // pr_data
-  OutStreamer.emitValueToAlignment(NoteAlign); // pr_padding
+  if (Triple.isArch64Bit())
+    OutStreamer.emitIntValue(0, 4);            // pr_padding
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MaskRay wrote:

Looks like GCC uses trailing alignment directive as well. Sorry, I take back my previous statement. We can use an alignment at the note entry end.

https://github.com/llvm/llvm-project/pull/151436