[llvm] r215837 - Fix an off-by-one bug in the target independent llvm-objdump.

[Rafael Espindola]

Author: rafael
Date: Sun Aug 17 11:31:39 2014
New Revision: 215837

URL: http://llvm.org/viewvc/llvm-project?rev=215837&view=rev
Log:
Fix an off-by-one bug in the target independent llvm-objdump.

It would prevent the display of a single byte instruction before a label.

Patch by Steve King!

Added:
    llvm/trunk/test/Object/Inputs/trivial-label-test.elf-x86-64
    llvm/trunk/test/Object/X86/objdump-label.test
Modified:
    llvm/trunk/tools/llvm-objdump/llvm-objdump.cpp

Added: llvm/trunk/test/Object/Inputs/trivial-label-test.elf-x86-64
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/Inputs/trivial-label-test.elf-x86-64?rev=215837&view=auto
==============================================================================
Binary files llvm/trunk/test/Object/Inputs/trivial-label-test.elf-x86-64 (added) and llvm/trunk/test/Object/Inputs/trivial-label-test.elf-x86-64 Sun Aug 17 11:31:39 2014 differ

Added: llvm/trunk/test/Object/X86/objdump-label.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Object/X86/objdump-label.test?rev=215837&view=auto
==============================================================================
--- llvm/trunk/test/Object/X86/objdump-label.test (added)
+++ llvm/trunk/test/Object/X86/objdump-label.test Sun Aug 17 11:31:39 2014
@@ -0,0 +1,10 @@
+RUN: llvm-objdump -d %p/../Inputs/trivial-label-test.elf-x86-64 \
+RUN:              | FileCheck %s -check-prefix ELF-x86-64
+
+ELF-x86-64: file format ELF64-x86-64
+ELF-x86-64: Disassembly of section .text:
+ELF-x86-64: foo:
+ELF-x86-64:        0:	90                                           	nop
+ELF-x86-64: bum:
+ELF-x86-64:        1:	90                                           	nop
+

Modified: llvm/trunk/tools/llvm-objdump/llvm-objdump.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-objdump/llvm-objdump.cpp?rev=215837&r1=215836&r2=215837&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-objdump/llvm-objdump.cpp (original)
+++ llvm/trunk/tools/llvm-objdump/llvm-objdump.cpp Sun Aug 17 11:31:39 2014
@@ -494,17 +494,12 @@ static void DisassembleObject(const Obje
     std::vector<RelocationRef>::const_iterator rel_end = Rels.end();
     // Disassemble symbol by symbol.
     for (unsigned si = 0, se = Symbols.size(); si != se; ++si) {
+
       uint64_t Start = Symbols[si].first;
-      uint64_t End;
-      // The end is either the size of the section or the beginning of the next
-      // symbol.
-      if (si == se - 1)
-        End = SectSize;
-      // Make sure this symbol takes up space.
-      else if (Symbols[si + 1].first != Start)
-        End = Symbols[si + 1].first - 1;
-      else
-        // This symbol has the same address as the next symbol. Skip it.
+      // The end is either the section end or the beginning of the next symbol.
+      uint64_t End = (si == se - 1) ? SectSize : Symbols[si + 1].first;
+      // If this symbol has the same address as the next symbol, then skip it.
+      if (Start == End)
         continue;
 
       outs() << '\n' << Symbols[si].second << ":\n";