From 819dd52416d105d534fb75c8b89b1c3df475c95d Mon Sep 17 00:00:00 2001
From: Csoregi Natalia <ncsoregi@mozilla.com>
Date: Tue, 26 Mar 2019 11:32:42 +0200
Subject: [PATCH] Backed out changeset abf6af5e36d6 (bug 1537725) for bustages
 on libdav1d/moz.build. CLOSED TREE

---
 media/libdav1d/asm/moz.build             | 13 ++++------
 media/libdav1d/asm/x86_32/win/config.asm |  2 +-
 media/libdav1d/moz.build                 | 30 +++++++++---------------
 3 files changed, 16 insertions(+), 29 deletions(-)

diff --git a/media/libdav1d/asm/moz.build b/media/libdav1d/asm/moz.build
index ca89221c98cf..b12240139789 100644
--- a/media/libdav1d/asm/moz.build
+++ b/media/libdav1d/asm/moz.build
@@ -25,17 +25,16 @@ CFLAGS += [
     '-I%s/dist/include/dav1d/' % TOPOBJDIR,
 ]
 
-stack_alignment = 0
+# Default stack aligment is 16 bytes.
+stack_alignment = 16
+
 # Attaching config.asm file
 if CONFIG['CPU_ARCH'] == 'x86':
-    # Default stack alignment can be 4 bytes.
     if CONFIG['OS_TARGET'] == 'WINNT':
-        stack_alignment = 4
         ASFLAGS += ['-I%s/media/libdav1d/asm/x86_32/win/' % TOPSRCDIR]
     else:
         ASFLAGS += ['-I%s/media/libdav1d/asm/x86_32/' % TOPSRCDIR]
-        stack_alignment = 16
-        # Change stack alignment to 16 bytes.
+        # Default stack aligment can be 4 bytes, change it to 16 bytes.
         if CONFIG['CC_TYPE'] == 'clang':
             CFLAGS += ['-mstack-alignment=16']
         elif CONFIG['CC_TYPE'] == 'gcc':
@@ -43,8 +42,6 @@ if CONFIG['CPU_ARCH'] == 'x86':
 
 
 if CONFIG['CPU_ARCH'] == 'x86_64':
-    # Default stack aligment is 16 bytes.
-    stack_alignment = 16
     if CONFIG['OS_TARGET'] == 'Darwin':
         ASFLAGS += ['-I%s/media/libdav1d/asm/x86_64/osx/' % TOPSRCDIR]
     elif CONFIG['OS_TARGET'] == 'WINNT':
@@ -65,8 +62,6 @@ if CONFIG['CPU_ARCH'] == 'x86_64':
             CFLAGS += ['-mpreferred-stack-boundary=5']
 
 # Set the macro here instead of config.h
-if stack_alignment == 0:
-    error('Stack alignment cannot be zero.')
 DEFINES['STACK_ALIGNMENT'] = stack_alignment
 
 if CONFIG['CPU_ARCH'] in ('x86', 'x86_64'):
diff --git a/media/libdav1d/asm/x86_32/win/config.asm b/media/libdav1d/asm/x86_32/win/config.asm
index f701a081aa86..e5f09a91a86d 100644
--- a/media/libdav1d/asm/x86_32/win/config.asm
+++ b/media/libdav1d/asm/x86_32/win/config.asm
@@ -9,5 +9,5 @@
 
 %define PREFIX 1
 
-%define STACK_ALIGNMENT 4
+%define STACK_ALIGNMENT 16
 
diff --git a/media/libdav1d/moz.build b/media/libdav1d/moz.build
index 9a3b686d3b60..788c1a5ab971 100644
--- a/media/libdav1d/moz.build
+++ b/media/libdav1d/moz.build
@@ -32,26 +32,20 @@ DEFINES['DAV1D_API'] = ''
 if CONFIG['MOZ_DAV1D_ASM']:
     DIRS += ['asm']
 
-    # Store the stack alignment that will be used.
-    stack_alignment = 0
-
     # Default stack alignment can be 4 bytes on x86.
     if CONFIG['CPU_ARCH'] == 'x86':
-        if CONFIG['OS_TARGET'] == 'WINNT':
-            # Allow the default to avoid crashes
-            stack_alignment = 4
-        else:
-            # Update stack alignment to 16 bytes.
-            stack_alignment = 16
-            if CONFIG['CC_TYPE'] == 'clang':
-                CFLAGS += ['-mstack-alignment=16']
-                for ep in entrypoint_source_files:
-                    SOURCES[ep].flags += ['-mstackrealign']
-            elif CONFIG['CC_TYPE'] == 'gcc':
-                CFLAGS += ['-mpreferred-stack-boundary=4']
-                for ep in entrypoint_source_files:
-                    SOURCES[ep].flags += ['-mincoming-stack-boundary=2']
+        # Update stack alignment to 16 bytes.
+        if CONFIG['CC_TYPE'] == 'clang':
+            CFLAGS += ['-mstack-alignment=16']
+            for ep in entrypoint_source_files:
+                SOURCES[ep].flags += ['-mstackrealign']
+        elif CONFIG['CC_TYPE'] == 'gcc':
+            CFLAGS += ['-mpreferred-stack-boundary=4']
+            for ep in entrypoint_source_files:
+                SOURCES[ep].flags += ['-mincoming-stack-boundary=2']
 
+    # Expect stack alignment of 16 bytes.
+    stack_alignment = 16
 
     # The default stack alignment in x86_64 is 16 bytes. On all Linux flavors the
     # default is used due to crashes with 32 bytes stack alignment.
@@ -68,8 +62,6 @@ if CONFIG['MOZ_DAV1D_ASM']:
                 SOURCES[ep].flags += ['-mincoming-stack-boundary=4']
 
     # Set the macro here instead of config.h
-    if stack_alignment == 0:
-        error('Stack alignment cannot be zero.')
     DEFINES['STACK_ALIGNMENT'] = stack_alignment
 
 if CONFIG['OS_TARGET'] == 'Linux':