Disable SSE2

build/common.gypi

Index: build/common.gypi
===================================================================
--- build/common.gypi	(revision 47483)
+++ build/common.gypi	(working copy)
@@ -106,9 +106,6 @@
 
       # The system root for cross-compiles. Default: none.
       'sysroot%': '',
-
-      # On Linux, we build with sse2 for Chromium builds.
-      'disable_sse2%': 0,
     },
 
     # Define branding and buildtype on the basis of their settings within the
@@ -126,7 +123,6 @@
     'armv7%': '<(armv7)',
     'arm_neon%': '<(arm_neon)',
     'sysroot%': '<(sysroot)',
-    'disable_sse2%': '<(disable_sse2)',
 
     # The release channel that this build targets. This is used to restrict
     # channel-specific build options, like which installer packages to create.
@@ -963,27 +959,17 @@
             # floating-values in the memory, thus force them to be rounded
             # to its original precision) but they have significant runtime
             # performance penalty.
-            #
-            # -mfpmath=sse -msse2 makes the compiler use SSE instructions
-            # which keep floating-point values in SSE registers in its
-            # native precision (32-bit for single precision, and 64-bit for
-            # double precision values). This means the floating-point value
-            # used during computation does not change depending on how the
-            # compiler optimized the code, since the value is always kept
-            # in its specified precision.
             'conditions': [
-              ['branding=="Chromium" and disable_sse2==0', {
+              ['branding=="Chromium"', {
                 'cflags': [
                   '-march=pentium4',
-                  '-msse2',
-                  '-mfpmath=sse',
                 ],
               }],
               # ChromeOS targets Pinetrail, which is sse3, but most of the
               # benefit comes from sse2 so this setting allows ChromeOS
               # to build on other CPUs.  In the future -march=atom would help
               # but requires a newer compiler.
-              ['chromeos==1 and disable_sse2==0', {
+              ['chromeos==1', {
                 'cflags': [
                   '-msse2',
                 ],