!188 compiler & openEuler oeaware schedule opt

From: @flyahead1 
Reviewed-by: @liyunfei33 
Signed-off-by: @liyunfei33

Author: openeuler-ci-bot

lld/ELF/Config.h

@@ -338,6 +338,7 @@ struct Config {
   uint8_t zStartStopVisibility;
   bool zText;
   bool zRetpolineplt;
+  int8_t zOeawarePolicy;
   bool zWxneeded;
   DiscardPolicy discard;
   GnuStackKind zGnustack;

lld/ELF/Driver.cpp

@@ -1501,6 +1501,7 @@ static void readConfigs(opt::InputArgList &args) {
   config->zStartStopVisibility = getZStartStopVisibility(args);
   config->zText = getZFlag(args, "text", "notext", true);
   config->zWxneeded = hasZOption(args, "wxneeded");
+  config->zOeawarePolicy = args::getZOptionValue(args, OPT_z,  "oeaware-policy", -1);
   setUnresolvedSymbolPolicy(args);
   config->power10Stubs = args.getLastArgValue(OPT_power10_stubs_eq) != "no";
 

lld/ELF/SyntheticSections.cpp

@@ -4922,8 +4922,21 @@ template <class ELFT> void elf::createSyntheticSections() {
   add(*in.shStrTab);
   if (in.strTab)
     add(*in.strTab);
+  if (config->zOeawarePolicy != -1) {
+    in.oeaware = std::make_unique<OeAware>();
+    add(*in.oeaware);
+  }
+}
+
+void OeAware::writeTo(uint8_t *buf) {
+  if (config->zOeawarePolicy != -1)
+    write32(buf, config->zOeawarePolicy);
 }
 
+size_t OeAware::getSize() const { return 4; }
+
+void OeAware::finalizeContents() {}
+
 InStruct elf::in;
 
 std::vector<Partition> elf::partitions;

lld/ELF/SyntheticSections.h

@@ -1425,6 +1425,20 @@ class MemtagGlobalDescriptors final : public SyntheticSection {
   SmallVector<const Symbol *, 0> symbols;
 };
 
+class OeAware : public SyntheticSection {
+public:
+  OeAware()
+      : SyntheticSection(llvm::ELF::SHF_ALLOC | llvm::ELF::SHF_WRITE,
+                        llvm::ELF::SHT_NOTE, /*alignment=*/4, ".LLVM4OE_oeAware")
+        {}
+  void writeTo(uint8_t *buf) override;
+  size_t getSize() const override;
+  void finalizeContents() override;
+
+private:
+  uint64_t size;
+};
+
 template <class ELFT> void createSyntheticSections();
 InputSection *createInterpSection();
 MergeInputSection *createCommentSection();
@@ -1512,6 +1526,7 @@ struct InStruct {
   std::unique_ptr<StringTableSection> strTab;
   std::unique_ptr<SymbolTableBaseSection> symTab;
   std::unique_ptr<SymtabShndxSection> symTabShndx;
+  std::unique_ptr<SyntheticSection> oeaware;
 
   void reset();
 };

lld/ELF/Writer.cpp

@@ -1961,6 +1961,7 @@ template <class ELFT> void Writer<ELFT>::finalizeSections() {
     llvm::TimeTraceScope timeScope("Finalize synthetic sections");
 
     finalizeSynthetic(in.bss.get());
+    finalizeSynthetic(in.oeaware.get());
     finalizeSynthetic(in.bssRelRo.get());
     finalizeSynthetic(in.symTabShndx.get());
     finalizeSynthetic(in.shStrTab.get());

lld/test/ELF/oeaware.s

@@ -0,0 +1,17 @@
+# REQUIRES: target=aarch64{{.*}}
+# RUN: llvm-mc -filetype=obj -triple=aarch64-none-linux-gnu %s -o %t.o
+# RUN: ld.lld %t.o -o %ta -z oeaware-policy=1
+# RUN: llvm-objdump -j .LLVM4OE_oeAware %ta -d | FileCheck %s
+
+# CHECK: <.LLVM4OE_oeAware>:
+# CHECK-NEXT: 00000001
+
+# RUN: ld.lld %t.o -o %tb -z oeaware-policy=2
+# RUN: llvm-objdump -j .LLVM4OE_oeAware %tb -d | FileCheck %s --check-prefix=OPTION
+
+# OPTION: <.LLVM4OE_oeAware>:
+# OPTION-NEXT: 00000002
+
+.globl _start
+_start: nop
+.bss; .byte 0