[llvm-objdump] Emit warning if --start-address/--stop-address specify range outside file's address range.

NB: the warning is about the input file itself regardless of the options used
such as `-r`, `-s` etc..

https://bugs.llvm.org/show_bug.cgi?id=41911

Reviewers: jhenderson, grimar, MaskRay, rupprecht

Reviewed by: MaskRay, jhenderson

Differential Revision: https://reviews.llvm.org/D64779

llvm-svn: 366923

1 files changed, 37 insertions, 0 deletions

diff --git a/llvm/tools/llvm-objdump/llvm-objdump.cpp b/llvm/tools/llvm-objdump/llvm-objdump.cpp
index 58981203..042c485a 100644
--- a/llvm/tools/llvm-objdump/llvm-objdump.cpp
+++ b/llvm/tools/llvm-objdump/llvm-objdump.cpp
@@ -2010,6 +2010,40 @@ static void printArchiveChild(StringRef Filename, const Archive::Child &C) {
   outs() << Name << "\n";
 }
 
+// For ELF only now.
+static bool shouldWarnForInvalidStartStopAddress(ObjectFile *Obj) {
+  if (const auto *Elf = dyn_cast<ELFObjectFileBase>(Obj)) {
+    if (Elf->getEType() != ELF::ET_REL)
+      return true;
+  }
+  return false;
+}
+
+static void checkForInvalidStartStopAddress(ObjectFile *Obj,
+                                            uint64_t Start, uint64_t Stop) {
+  if (!shouldWarnForInvalidStartStopAddress(Obj))
+    return;
+
+  for (const SectionRef &Section : Obj->sections())
+    if (ELFSectionRef(Section).getFlags() & ELF::SHF_ALLOC) {
+      uint64_t BaseAddr = Section.getAddress();
+      uint64_t Size = Section.getSize();
+      if ((Start < BaseAddr + Size) && Stop > BaseAddr)
+        return;
+    }
+
+  if (StartAddress.getNumOccurrences() == 0)
+    warn("no section has address less than 0x" +
+         Twine::utohexstr(Stop) + " specified by --stop-address");
+  else if (StopAddress.getNumOccurrences() == 0)
+    warn("no section has address greater than or equal to 0x" +
+         Twine::utohexstr(Start) + " specified by --start-address");
+  else
+    warn("no section overlaps the range [0x" +
+         Twine::utohexstr(Start) + ",0x" + Twine::utohexstr(Stop) +
+         ") specified by --start-address/--stop-address");
+}
+
 static void dumpObject(ObjectFile *O, const Archive *A = nullptr,
                        const Archive::Child *C = nullptr) {
   // Avoid other output when using a raw option.
@@ -2022,6 +2056,9 @@ static void dumpObject(ObjectFile *O, const Archive *A = nullptr,
     outs() << ":\tfile format " << O->getFileFormatName() << "\n\n";
   }
 
+  if (StartAddress.getNumOccurrences() || StopAddress.getNumOccurrences())
+    checkForInvalidStartStopAddress(O, StartAddress, StopAddress);
+
   StringRef ArchiveName = A ? A->getFileName() : "";
   if (FileHeaders)
     printFileHeaders(O);