llvm-objdump: Do not attempt to disassemble symbols outside of section

boundaries.

It is possible to create an ELF executable where symbol from say .text
section 'points' to the address outside the section boundaries. It does
not have a sense to disassemble something outside the section.

Without this fix llvm-objdump prints finite or infinite (depends on
the executable file architecture) number of 'invalid instruction
encoding' warnings.

llvm-svn: 202083

1 files changed, 6 insertions, 3 deletions

diff --git a/llvm/tools/llvm-objdump/llvm-objdump.cpp b/llvm/tools/llvm-objdump/llvm-objdump.cpp
index 8d934cf9485..d8460fdb247 100644
--- a/llvm/tools/llvm-objdump/llvm-objdump.cpp
+++ b/llvm/tools/llvm-objdump/llvm-objdump.cpp
@@ -405,6 +405,10 @@ static void DisassembleObject(const ObjectFile *Obj, bool InlineRelocs) {
     if (error(I->getAddress(SectionAddr)))
       break;
 
+    uint64_t SectSize;
+    if (error(I->getSize(SectSize)))
+      break;
+
     // Make a list of all the symbols in this section.
     std::vector<std::pair<uint64_t, StringRef> > Symbols;
     for (symbol_iterator SI = Obj->symbol_begin(), SE = Obj->symbol_end();
@@ -417,6 +421,8 @@ static void DisassembleObject(const ObjectFile *Obj, bool InlineRelocs) {
         if (Address == UnknownAddressOrSize)
           continue;
         Address -= SectionAddr;
+        if (Address >= SectSize)
+          continue;
 
         StringRef Name;
         if (error(SI->getName(Name)))
@@ -473,9 +479,6 @@ static void DisassembleObject(const ObjectFile *Obj, bool InlineRelocs) {
     StringRefMemoryObject memoryObject(Bytes, SectionAddr);
     uint64_t Size;
     uint64_t Index;
-    uint64_t SectSize;
-    if (error(I->getSize(SectSize)))
-      break;
 
     std::vector<RelocationRef>::const_iterator rel_cur = Rels.begin();
     std::vector<RelocationRef>::const_iterator rel_end = Rels.end();