make code more conventional; simplify code; use just diag prefix in CHECK-NOT.

Author: MaskRay

lld/ELF/Driver.cpp

@@ -1629,7 +1629,7 @@ static void readConfigs(Ctx &ctx, opt::InputArgList &args) {
       std::make_pair("gcs-report", &ctx.arg.zGcsReport),
       std::make_pair("gcs-report-dynamic", &ctx.arg.zGcsReportDynamic),
       std::make_pair("pauth-report", &ctx.arg.zPauthReport)};
-  bool zGcsReportDynamicDefined = false;
+  bool hasGcsReportDynamic = false;
   for (opt::Arg *arg : args.filtered(OPT_z)) {
     std::pair<StringRef, StringRef> option =
         StringRef(arg->getValue()).split('=');
@@ -1639,29 +1639,23 @@ static void readConfigs(Ctx &ctx, opt::InputArgList &args) {
       arg->claim();
       if (option.second == "none")
         *reportArg.second = ReportPolicy::None;
-      else if (option.second == "warning") {
+      else if (option.second == "warning")
         *reportArg.second = ReportPolicy::Warning;
-        // To be able to match the GNU ld inheritance rules for -zgcs-report
-        // and -zgcs-report-dynamic, we need to know if -zgcs-report-dynamic
-        // has been defined by the user.
-        if (option.first == "gcs-report-dynamic")
-          zGcsReportDynamicDefined = true;
-      } else if (option.second == "error") {
+      else if (option.second == "error")
         *reportArg.second = ReportPolicy::Error;
-        if (option.first == "gcs-report-dynamic")
-          zGcsReportDynamicDefined = true;
-      } else {
+      else {
         ErrAlways(ctx) << "unknown -z " << reportArg.first
                        << "= value: " << option.second;
         continue;
       }
+      hasGcsReportDynamic |= option.first == "gcs-report-dynamic";
     }
   }
 
-  if (!zGcsReportDynamicDefined && ctx.arg.zGcsReport != ReportPolicy::None &&
-      ctx.arg.zGcsReportDynamic == ReportPolicy::None)
-    // When inheriting the -zgcs-report option, it is capped at a `warning` to
-    // avoid needing to rebuild the shared library with GCS enabled.
+  // When -zgcs-report-dynamic is unspecified, it inherits -zgcs-report
+  // but is capped at warning to avoid needing to rebuild the shared library
+  // with GCS enabled.
+  if (!hasGcsReportDynamic && ctx.arg.zGcsReport != ReportPolicy::None)
     ctx.arg.zGcsReportDynamic = ReportPolicy::Warning;
 
   for (opt::Arg *arg : args.filtered(OPT_compress_sections)) {

lld/ELF/InputFiles.cpp

@@ -1434,30 +1434,23 @@ std::vector<uint32_t> SharedFile::parseVerneed(const ELFFile<ELFT> &obj,
   return verneeds;
 }
 
-// To determine if a shared file can support any of the GNU Attributes,
-// the .note.gnu.properties section need to be read. The appropriate
-// location in memory is located then the GnuPropertyNote can be parsed.
-// This is the same process as is used for readGnuProperty, however we
-// do not pass the data variable as, without an InputSection, its value
-// is unknown in a SharedFile. This is ok as the information that would
-// be collected from this is irrelevant for a dynamic object.
+// Parse PT_GNU_PROPERTY segments in DSO. The process is similar to
+// readGnuProperty, but we don't have the InputSection information.
 template <typename ELFT>
-void SharedFile::parseGnuAndFeatures(const uint8_t *base,
-                                     const typename ELFT::PhdrRange headers) {
-  if (headers.size() == 0 || ctx.arg.emachine != EM_AARCH64)
+void SharedFile::parseGnuAndFeatures(const ELFFile<ELFT> &obj) {
+  if (ctx.arg.emachine != EM_AARCH64)
     return;
-
-  for (unsigned i = 0; i < headers.size(); i++) {
-    if (headers[i].p_type != PT_GNU_PROPERTY)
+  const uint8_t *base = obj.base();
+  auto phdrs = CHECK2(obj.program_headers(), this);
+  for (auto phdr : phdrs) {
+    if (phdr.p_type != PT_GNU_PROPERTY)
       continue;
-    const typename ELFT::Note note(
-        *reinterpret_cast<const typename ELFT::Nhdr *>(base +
-                                                       headers[i].p_offset));
+    typename ELFT::Note note(
+        *reinterpret_cast<const typename ELFT::Nhdr *>(base + phdr.p_offset));
     if (note.getType() != NT_GNU_PROPERTY_TYPE_0 || note.getName() != "GNU")
       continue;
 
-    // Read a body of a NOTE record, which consists of type-length-value fields.
-    ArrayRef<uint8_t> desc = note.getDesc(headers[i].p_align);
+    ArrayRef<uint8_t> desc = note.getDesc(phdr.p_align);
     parseGnuPropertyNote<ELFT>(ctx, *this, GNU_PROPERTY_AARCH64_FEATURE_1_AND,
                                desc, base);
   }
@@ -1499,12 +1492,10 @@ template <class ELFT> void SharedFile::parse() {
   using Elf_Sym = typename ELFT::Sym;
   using Elf_Verdef = typename ELFT::Verdef;
   using Elf_Versym = typename ELFT::Versym;
-  using Elf_Phdr = typename ELFT::Phdr;
 
   ArrayRef<Elf_Dyn> dynamicTags;
   const ELFFile<ELFT> obj = this->getObj<ELFT>();
   ArrayRef<Elf_Shdr> sections = getELFShdrs<ELFT>();
-  ArrayRef<Elf_Phdr> pHeaders = CHECK2(obj.program_headers(), this);
 
   const Elf_Shdr *versymSec = nullptr;
   const Elf_Shdr *verdefSec = nullptr;
@@ -1575,7 +1566,7 @@ template <class ELFT> void SharedFile::parse() {
 
   verdefs = parseVerdefs<ELFT>(obj.base(), verdefSec);
   std::vector<uint32_t> verneeds = parseVerneed<ELFT>(obj, verneedSec);
-  parseGnuAndFeatures<ELFT>(obj.base(), pHeaders);
+  parseGnuAndFeatures<ELFT>(obj);
 
   // Parse ".gnu.version" section which is a parallel array for the symbol
   // table. If a given file doesn't have a ".gnu.version" section, we use

lld/ELF/InputFiles.h

@@ -365,8 +365,7 @@ class SharedFile : public ELFFileBase {
   std::vector<uint32_t> parseVerneed(const llvm::object::ELFFile<ELFT> &obj,
                                      const typename ELFT::Shdr *sec);
   template <typename ELFT>
-  void parseGnuAndFeatures(const uint8_t *base,
-                           const typename ELFT::PhdrRange headers);
+  void parseGnuAndFeatures(const llvm::object::ELFFile<ELFT> &obj);
 };
 
 class BinaryFile : public InputFile {

lld/test/ELF/aarch64-feature-gcs.s

@@ -59,9 +59,9 @@
 # RUN: ld.lld func1-gcs.o func3-gcs.o force-gcs.so -z gcs-report-dynamic=error -z gcs=always 2>&1 | count 0
 
 # REPORT-WARN-DYNAMIC: warning: no-gcs.so: GCS is required by -z gcs, but this shared library lacks the necessary property note. The dynamic loader might not enable GCS or refuse to load the program unless all shared library dependencies have the GCS marking.
-# REPORT-WARN-DYNAMIC-NOT: warning: force-gcs.so: GCS is required by -z gcs, but this shared library lacks the necessary property note. The dynamic loader might not enable GCS or refuse to load the program unless all shared library dependencies have the GCS marking.
+# REPORT-WARN-DYNAMIC-NOT: warning:
 # REPORT-ERROR-DYNAMIC: error: no-gcs.so: GCS is required by -z gcs, but this shared library lacks the necessary property note. The dynamic loader might not enable GCS or refuse to load the program unless all shared library dependencies have the GCS marking.
-# REPORT-ERROR-DYNAMIC-NOT: error: force-gcs.so: GCS is required by -z gcs, but this shared library lacks the necessary property note. The dynamic loader might not enable GCS or refuse to load the program unless all shared library dependencies have the GCS marking.
+# REPORT-ERROR-DYNAMIC-NOT: error:
 
 ## An invalid gcs option should give an error
 # RUN: not ld.lld func1-gcs.o func2-gcs.o func3-gcs.o -z gcs=nonsense -z gcs-report=nonsense -z gcs-report-dynamic=nonsense 2>&1 | FileCheck --check-prefix=INVALID %s