Bug 1538455 - Use the default stack alignment in windows x64 for libdav1d. r=TD-Linux

Differential Revision: https://phabricator.services.mozilla.com/D25123

--HG--
extra : moz-landing-system : lando

media/libdav1d/asm/moz.build

@@ -25,7 +25,9 @@ CFLAGS += [
     '-I%s/dist/include/dav1d/' % TOPOBJDIR,
 ]
 
+# Store the stack alignment that will be used.
 stack_alignment = 0
+
 # Attaching config.asm file
 if CONFIG['CPU_ARCH'] == 'x86':
     # Default stack alignment can be 4 bytes.
@@ -40,29 +42,21 @@ if CONFIG['CPU_ARCH'] == 'x86':
             CFLAGS += ['-mstack-alignment=16']
         elif CONFIG['CC_TYPE'] == 'gcc':
             CFLAGS += ['-mpreferred-stack-boundary=4']
-
-
-if CONFIG['CPU_ARCH'] == 'x86_64':
+elif 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':
-        ASFLAGS += ['-I%s/media/libdav1d/asm/x86_64/' % TOPSRCDIR]
+        ASFLAGS += ['-I%s/media/libdav1d/asm/x86_64/win/' % TOPSRCDIR]
     elif CONFIG['OS_TARGET'] == 'Android':
         error('Platform %s is not expected' % CONFIG['OS_TARGET'])
     else:
         # The rest of the platforms are all Linux flavors
         # Linux,OpenBSD,NetBSD,FreeBSD,DragonFly,SunOS
         ASFLAGS += ['-I%s/media/libdav1d/asm/x86_64/linux/' % TOPSRCDIR]
-
-    if CONFIG['OS_TARGET'] == 'WINNT':
-        # Change the default stack alignment (16) to 32 bytes.
-        stack_alignment = 32
-        if CONFIG['CC_TYPE'] == 'clang':
-            CFLAGS += ['-mstack-alignment=32']
-        elif CONFIG['CC_TYPE'] == 'gcc':
-            CFLAGS += ['-mpreferred-stack-boundary=5']
+else:
+    error('Cpu arch %s is not expected' % CONFIG['CPU_ARCH'])
 
 # Set the macro here instead of config.h
 if stack_alignment == 0:

media/libdav1d/asm/x86_64/win/config.asm

@@ -0,0 +1,11 @@
+; Autogenerated by the Meson build system.
+; Do not edit, your changes will be lost.
+
+%define ARCH_X86_32 0
+
+%define ARCH_X86_64 1
+
+%define PIC 1
+
+%define STACK_ALIGNMENT 16
+

media/libdav1d/moz.build

@@ -51,23 +51,11 @@ if CONFIG['MOZ_DAV1D_ASM']:
                 CFLAGS += ['-mpreferred-stack-boundary=4']
                 for ep in entrypoint_source_files:
                     SOURCES[ep].flags += ['-mincoming-stack-boundary=2']
-
-
-    # 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.
-    if CONFIG['OS_TARGET'] == 'WINNT' and CONFIG['CPU_ARCH'] == 'x86_64':
-        stack_alignment = 32
-        # Update stack alignment to 32 bytes.
-        if CONFIG['CC_TYPE'] == 'clang':
-            CFLAGS += ['-mstack-alignment=32']
-            for ep in entrypoint_source_files:
-                SOURCES[ep].flags += ['-mstackrealign']
-        elif CONFIG['CC_TYPE'] == 'gcc':
-            CFLAGS += ['-mpreferred-stack-boundary=5']
-            for ep in entrypoint_source_files:
-                SOURCES[ep].flags += ['-mincoming-stack-boundary=4']
-    else:
+    elif CONFIG['CPU_ARCH'] == 'x86_64':
+        # The default stack alignment in x86_64 is 16 bytes.
         stack_alignment = 16
+    else:
+        error('Cpu arch %s is not expected' % CONFIG['CPU_ARCH'])
 
     # Set the macro here instead of config.h
     if stack_alignment == 0: