Make usage of simd in gfx optional

components/gfx/Cargo.toml

@@ -10,6 +10,9 @@ publish = false
 name = "gfx"
 path = "lib.rs"
 
+[features]
+unstable = ["simd"]
+
 [dependencies]
 app_units = "0.5"
 bitflags = "0.7"
@@ -58,7 +61,7 @@ servo-fontconfig = "0.2.1"
 xml5ever = {version = "0.10"}
 
 [target.'cfg(any(target_feature = "sse2", target_feature = "neon"))'.dependencies]
-simd = "0.2.0"
+simd = {version = "0.2.0", optional = true}
 
 [target.'cfg(target_os = "windows")'.dependencies]
 dwrote = "0.4"

components/gfx/lib.rs

@@ -3,8 +3,8 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 // For SIMD
+#![cfg_attr(feature = "unstable", feature(cfg_target_feature))]
 #![cfg_attr(any(target_os = "linux", target_os = "android"), feature(allocator_api))]
-#![feature(cfg_target_feature)]
 
 #![deny(unsafe_code)]
 
@@ -53,6 +53,7 @@ extern crate servo_arc;
 extern crate servo_geometry;
 extern crate servo_url;
 #[macro_use] extern crate servo_atoms;
+#[cfg(feature = "unstable")]
 #[cfg(any(target_feature = "sse2", target_feature = "neon"))]
 extern crate simd;
 extern crate smallvec;

components/gfx/text/glyph.rs

@@ -5,7 +5,7 @@
 use app_units::Au;
 use euclid::Point2D;
 use range::{self, EachIndex, Range, RangeIndex};
-#[cfg(any(target_feature = "sse2", target_feature = "neon"))]
+#[cfg(all(feature = "unstable", any(target_feature = "sse2", target_feature = "neon")))]
 use simd::u32x4;
 use std::{fmt, mem, u16};
 use std::cmp::{Ordering, PartialOrd};
@@ -74,6 +74,7 @@ pub type GlyphId = u32;
 // TODO: make this more type-safe.
 
 const FLAG_CHAR_IS_SPACE: u32       = 0x40000000;
+#[cfg(feature = "unstable")]
 #[cfg(any(target_feature = "sse2", target_feature = "neon"))]
 const FLAG_CHAR_IS_SPACE_SHIFT: u32 = 30;
 const FLAG_IS_SIMPLE_GLYPH: u32     = 0x80000000;
@@ -591,6 +592,7 @@ impl<'a> GlyphStore {
     }
 
     #[inline]
+    #[cfg(feature = "unstable")]
     #[cfg(any(target_feature = "sse2", target_feature = "neon"))]
     fn advance_for_byte_range_simple_glyphs(&self, range: &Range<ByteIndex>, extra_word_spacing: Au) -> Au {
         let advance_mask = u32x4::splat(GLYPH_ADVANCE_MASK);
@@ -634,13 +636,14 @@ impl<'a> GlyphStore {
 
     /// When SIMD isn't available, fallback to the slow path.
     #[inline]
-    #[cfg(not(any(target_feature = "sse2", target_feature = "neon")))]
+    #[cfg(not(all(feature = "unstable", any(target_feature = "sse2", target_feature = "neon"))))]
     fn advance_for_byte_range_simple_glyphs(&self, range: &Range<ByteIndex>, extra_word_spacing: Au) -> Au {
         self.advance_for_byte_range_slow_path(range, extra_word_spacing)
     }
 
     /// Used for SIMD.
     #[inline]
+    #[cfg(feature = "unstable")]
     #[cfg(any(target_feature = "sse2", target_feature = "neon"))]
     #[allow(unsafe_code)]
     fn transmute_entry_buffer_to_u32_buffer(&self) -> &[u32] {

components/servo/Cargo.toml

@@ -25,6 +25,7 @@ unstable = [
     "canvas_traits/unstable",
     "compositing/unstable",
     "constellation/unstable",
+    "gfx/unstable",
 ]
 
 [dependencies]