From f148a6d498e2636ef82b44e0d0aecd72209aca35 Mon Sep 17 00:00:00 2001
From: Joerg Sonnenberger <joerg@bec.de>
Date: Thu, 2 Oct 2014 13:41:42 +0000
Subject: [PATCH] Support padding unaligned data in .text.

llvm-svn: 218870
---
 llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp | 7 ++++++-
 llvm/test/MC/Mips/unaligned-nops.s                   | 4 ++++
 2 files changed, 10 insertions(+), 1 deletion(-)
 create mode 100644 llvm/test/MC/Mips/unaligned-nops.s

diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
index d8e6128cd54d..efeb54d91b89 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
@@ -367,7 +367,12 @@ bool MipsAsmBackend::writeNopData(uint64_t Count, MCObjectWriter *OW) const {
   // Check for a less than instruction size number of bytes
   // FIXME: 16 bit instructions are not handled yet here.
   // We shouldn't be using a hard coded number for instruction size.
-  if (Count % 4) return false;
+
+  // If the count is not 4-byte aligned, we must be writing data into the text
+  // section (otherwise we have unaligned instructions, and thus have far
+  // bigger problems), so just write zeros instead.
+  for (uint64_t i = 0, e = Count % 4; i != e; ++i)
+    OW->Write8(0);
 
   uint64_t NumNops = Count / 4;
   for (uint64_t i = 0; i != NumNops; ++i)
diff --git a/llvm/test/MC/Mips/unaligned-nops.s b/llvm/test/MC/Mips/unaligned-nops.s
new file mode 100644
index 000000000000..ebbbb40f4dc6
--- /dev/null
+++ b/llvm/test/MC/Mips/unaligned-nops.s
@@ -0,0 +1,4 @@
+# RUN: llvm-mc -filetype=obj  -triple=mipsel %s -o %t
+.byte 1
+.p2align 2
+foo: