From 0d88e15454b632d92404dd6a7181c58d9985e2a2 Mon Sep 17 00:00:00 2001
From: Rahul Chaudhry <rahulchaudhry@google.com>
Date: Tue, 9 May 2017 12:00:58 -0700
Subject: [PATCH] Add visibility="protected" attribute for global variables
 referenced in asm files.

During aosp builds with binutils-2.27, we're seeing linker error
messages of this form:
libvpx.a(subpixel_mmx.o): relocation R_386_GOTOFF against preemptible
symbol vp8_bilinear_filters_x86_8 cannot be used when making a shared
object

subpixel_mmx.o is assembled from "vp8/common/x86/subpixel_mmx.asm".
Other messages refer to symbol references from deblock_sse2.o and
subpixel_sse2.o, also assembled from asm files.

This change marks such symbols as having "protected" visibility. This
satisfies the linker as the symbols are not preemptible from outside
the shared library now, which I think is the original intent anyway.

Change-Id: I2817f7a5f43041533d65ebf41aefd63f8581a452
---
 vp8/common/x86/filter_x86.c | 3 ++-
 vpx_dsp/deblock.c           | 4 ++--
 vpx_ports/mem.h             | 6 ++++++
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/vp8/common/x86/filter_x86.c b/vp8/common/x86/filter_x86.c
index 2405342f0..73435a7dd 100644
--- a/vp8/common/x86/filter_x86.c
+++ b/vp8/common/x86/filter_x86.c
@@ -17,7 +17,8 @@ DECLARE_ALIGNED(16, const short, vp8_bilinear_filters_x86_4[8][8]) = {
   { 32, 32, 32, 32, 96, 96, 96, 96 }, { 16, 16, 16, 16, 112, 112, 112, 112 }
 };
 
-DECLARE_ALIGNED(16, const short, vp8_bilinear_filters_x86_8[8][16]) = {
+DECLARE_PROTECTED(DECLARE_ALIGNED(16, const short,
+                                  vp8_bilinear_filters_x86_8[8][16])) = {
   { 128, 128, 128, 128, 128, 128, 128, 128, 0, 0, 0, 0, 0, 0, 0, 0 },
   { 112, 112, 112, 112, 112, 112, 112, 112, 16, 16, 16, 16, 16, 16, 16, 16 },
   { 96, 96, 96, 96, 96, 96, 96, 96, 32, 32, 32, 32, 32, 32, 32, 32 },
diff --git a/vpx_dsp/deblock.c b/vpx_dsp/deblock.c
index a0db1e40c..3734ac251 100644
--- a/vpx_dsp/deblock.c
+++ b/vpx_dsp/deblock.c
@@ -10,9 +10,9 @@
 #include <assert.h>
 #include <stdlib.h>
 #include "./vpx_dsp_rtcd.h"
-#include "vpx/vpx_integer.h"
+#include "vpx_ports/mem.h"
 
-const int16_t vpx_rv[] = {
+DECLARE_PROTECTED(const int16_t vpx_rv[]) = {
   8,  5,  2,  2,  8,  12, 4,  9,  8,  3,  0,  3,  9,  0,  0,  0,  8,  3,  14,
   4,  10, 1,  11, 14, 1,  14, 9,  6,  12, 11, 8,  6,  10, 0,  0,  8,  9,  0,
   3,  14, 8,  11, 13, 4,  2,  9,  0,  3,  9,  6,  1,  2,  3,  14, 13, 1,  8,
diff --git a/vpx_ports/mem.h b/vpx_ports/mem.h
index bfef783b1..35751cef8 100644
--- a/vpx_ports/mem.h
+++ b/vpx_ports/mem.h
@@ -23,6 +23,12 @@
 #define DECLARE_ALIGNED(n, typ, val) typ val
 #endif
 
+#if defined(__GNUC__) && __GNUC__ >= 4 && !defined(_WIN32)
+#define DECLARE_PROTECTED(decl) decl __attribute__((visibility("protected")))
+#else
+#define DECLARE_PROTECTED(decl) decl
+#endif
+
 #if HAVE_NEON && defined(_MSC_VER)
 #define __builtin_prefetch(x)
 #endif
-- 
2.15.1