Disassemble the start of sections even if there is no symbol there.

We already handled a section with no symbols, extend that to also handle a
section with symbols that don't include the section start.

llvm-svn: 239039

3 files changed, 12 insertions, 5 deletions

diff --git a/llvm/test/Object/Inputs/no-start-symbol.elf-x86_64 b/llvm/test/Object/Inputs/no-start-symbol.elf-x86_64
new file mode 100644
index 00000000000..b2c9edc300d
--- /dev/null
+++ b/llvm/test/Object/Inputs/no-start-symbol.elf-x86_64
diff --git a/llvm/test/Object/no-start-symbol.test b/llvm/test/Object/no-start-symbol.test
new file mode 100644
index 00000000000..ea8e6db8dbf
--- /dev/null
+++ b/llvm/test/Object/no-start-symbol.test
@@ -0,0 +1,9 @@
+RUN: llvm-objdump -d %p/Inputs/no-start-symbol.elf-x86_64 | FileCheck %s
+
+Test that we disassemble the start of the section.
+
+CHECK: Disassembly of section .text:
+CHECK-NEXT:  .text:
+CHECK-NEXT:       0:	90 	nop
+CHECK: foo:
+CHECK-NEXT:       1:	90 	nop
diff --git a/llvm/tools/llvm-objdump/llvm-objdump.cpp b/llvm/tools/llvm-objdump/llvm-objdump.cpp
index d03556c4615..58600f62f4d 100644
--- a/llvm/tools/llvm-objdump/llvm-objdump.cpp
+++ b/llvm/tools/llvm-objdump/llvm-objdump.cpp
@@ -809,11 +809,9 @@ static void DisassembleObject(const ObjectFile *Obj, bool InlineRelocs) {
       outs() << SegmentName << ",";
     outs() << name << ':';
 
-    // If the section has no symbols just insert a dummy one and disassemble
-    // the whole section.
-    if (Symbols.empty())
-      Symbols.push_back(std::make_pair(0, name));
-
+    // If the section has no symbol at the start, just insert a dummy one.
+    if (Symbols.empty() || Symbols[0].first != 0)
+      Symbols.insert(Symbols.begin(), std::make_pair(0, name));
 
     SmallString<40> Comments;
     raw_svector_ostream CommentStream(Comments);