Adding yasm_include.gypi to reuse rules for compiling assembly files

third_party/yasm/yasm_compile.gypi

+# Copyright (c) 2011 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# This is an gyp include to use YASM for compiling assembly files.
+#
+# Files to be compiled with YASM should have an extension of .asm.
+#
+# There are two variables for this include:
+# yasm_flags : Pass additional flags into YASM.
+# yasm_output_path : Output directory for the compiled object files.
+#
+# Sample usage:
+# 'sources': [
+#   'ultra_optimized_awsome.asm',

[scherkus (not reviewing), 2011/09/06 16:51:13]

awsome -> awesome :)

[Alpha Left Google, 2011/09/06 17:12:13]

Done.

+# ],
+# 'variables': {
+#   'yasm_flags': [

[scherkus (not reviewing), 2011/09/06 16:51:13]

does including a gypi do a dictionary merge or a clobber?

for example, would -I get overwritten by the yasm_flags declared below?

[Alpha Left Google, 2011/09/06 17:12:13]

It'll be a merge.

+#     '-I', 'assembly_include',
+#   ],
+#   'yasm_output_path': '<(SHARED_INTERMEDIATE_DIR)/project',
+# },
+# 'includes': [
+#   'third_party/yasm/yasm_compile.gypi'
+# ],
+
+{
+  'variables': {
+    'yasm_path': '<(PRODUCT_DIR)/yasm',
+    'conditions': [
+      # Define yasm_flags that pass into YASM.
+      [ 'OS=="linux" and target_arch=="ia32"', {
+        'yasm_flags': [
+          '-felf32',
+          '-m', 'x86',
+        ],
+      }],
+      [ 'OS=="linux" and target_arch=="x64"', {
+        'yasm_flags': [
+          '-DPIC',
+          '-felf64',
+          '-m', 'amd64',
+        ],
+      }],
+      [ 'OS=="mac" and target_arch=="ia32"', {
+        'yasm_flags': [
+          '-fmacho32',
+          '-m', 'x86',
+        ],
+      }],
+      [ 'OS=="win" and target_arch=="ia32"', {
+        'yasm_flags': [
+          '-DPREFIX',
+          '-fwin32',
+          '-m', 'x86',
+        ],
+      }],
+
+      # Define output extension.
+      ['OS=="mac" or OS=="linux"', {
+        'asm_obj_extension': 'o',
+      }],
+      ['OS=="win"', {
+        'asm_obj_extension': 'obj',
+      }],
+    ],
+  },  # variables
+
+  'conditions': [
+    # Only depend on YASM on x86 systems, do this so that compiling
+    # .asm files for ARM will fail.

[scherkus (not reviewing), 2011/09/06 16:51:13]

interesting... I thought we were using YASM for ARM for FFmpeg

[Alpha Left Google, 2011/09/06 17:12:13]

YASM doesn't compile ARM code, it's for x86 only. For ARM it's the .S/.s files
which get compiled by gcc.

+    ['target_arch=="ia32" or target_arch=="x64"', {
+      'dependencies': [
+        '<(DEPTH)/third_party/yasm/yasm.gyp:yasm#host',
+      ],
+    }],
+  ],  # conditions
+
+  'rules': [
+    {
+      'rule_name': 'assemble',
+      'extension': 'asm',
+      'inputs': [ '<(yasm_path)', ],
+      'outputs': [
+        '<(yasm_output_path)/<(RULE_INPUT_ROOT).<(asm_obj_extension)',
+      ],
+      'action': [
+        '<(yasm_path)',
+        '<@(yasm_flags)',
+        '-o', '<(yasm_output_path)/<(RULE_INPUT_ROOT).<(asm_obj_extension)',
+        '<(RULE_INPUT_PATH)',
+      ],
+      'process_outputs_as_sources': 1,
+      'message': 'Compile assemly <(RULE_INPUT_PATH).',
+    },
+  ],  # rules
+}