The Tor Browser: mozglue/build/SSE.h@97036ab72558 (annotated)

mozglue/build/SSE.h@97036ab72558 (annotated)

mozglue/build/SSE.h

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 /* compile-time and runtime tests for whether to use SSE instructions */
 #ifndef mozilla_SSE_h_
 #define mozilla_SSE_h_
 // for definition of MFBT_DATA
 #include "mozilla/Types.h"
 /**
  * The public interface of this header consists of a set of macros and
  * functions for Intel CPU features.
  *
  * DETECTING ISA EXTENSIONS
  * ========================
  *
  * This header provides the following functions for determining whether the
  * current CPU supports a particular instruction set extension:
  *
  *    mozilla::supports_mmx
  *    mozilla::supports_sse
  *    mozilla::supports_sse2
  *    mozilla::supports_sse3
  *    mozilla::supports_ssse3
  *    mozilla::supports_sse4a
  *    mozilla::supports_sse4_1
  *    mozilla::supports_sse4_2
  *
  * If you're writing code using inline assembly, you should guard it with a
  * call to one of these functions.  For instance:
  *
  *   if (mozilla::supports_sse2()) {
  *     asm(" ... ");
  *   }
  *   else {
  *     ...
  *   }
  *
  * Note that these functions depend on cpuid intrinsics only available in gcc
  * 4.3 or later and MSVC 8.0 (Visual C++ 2005) or later, so they return false
  * in older compilers.  (This could be fixed by replacing the code with inline
  * assembly.)
  *
  *
  * USING INTRINSICS
  * ================
  *
  * This header also provides support for coding using CPU intrinsics.
  *
  * For each mozilla::supports_abc function, we define a MOZILLA_MAY_SUPPORT_ABC
  * macro which indicates that the target/compiler combination we're using is
  * compatible with the ABC extension.  For instance, x86_64 with MSVC 2003 is
  * compatible with SSE2 but not SSE3, since although there exist x86_64 CPUs
  * with SSE3 support, MSVC 2003 only supports through SSE2.
  *
  * Until gcc fixes #pragma target [1] [2] or our x86 builds require SSE2,
  * you'll need to separate code using intrinsics into a file separate from your
  * regular code.  Here's the recommended pattern:
  *
  *  #ifdef MOZILLA_MAY_SUPPORT_ABC
  *    namespace mozilla {
  *      namespace ABC {
  *        void foo();
  *      }
  *    }
  *  #endif
  *
  *  void foo() {
  *    #ifdef MOZILLA_MAY_SUPPORT_ABC
  *      if (mozilla::supports_abc()) {
  *        mozilla::ABC::foo(); // in a separate file
  *        return;
  *      }
  *    #endif
  *
  *    foo_unvectorized();
  *  }
  *
  * You'll need to define mozilla::ABC::foo() in a separate file and add the
  * -mabc flag when using gcc.
  *
  * [1] http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39787 and
  * [2] http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41201 being fixed.
  *
  */
 #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
 #ifdef __MMX__
   // It's ok to use MMX instructions based on the -march option (or
   // the default for x86_64 or for Intel Mac).
   #define MOZILLA_PRESUME_MMX 1
 #endif
 #ifdef __SSE__
   // It's ok to use SSE instructions based on the -march option (or
   // the default for x86_64 or for Intel Mac).
   #define MOZILLA_PRESUME_SSE 1
 #endif
 #ifdef __SSE2__
   // It's ok to use SSE2 instructions based on the -march option (or
   // the default for x86_64 or for Intel Mac).
   #define MOZILLA_PRESUME_SSE2 1
 #endif
 #ifdef __SSE3__
   // It's ok to use SSE3 instructions based on the -march option (or the
   // default for Intel Mac).
   #define MOZILLA_PRESUME_SSE3 1
 #endif
 #ifdef __SSSE3__
   // It's ok to use SSSE3 instructions based on the -march option.
   #define MOZILLA_PRESUME_SSSE3 1
 #endif
 #ifdef __SSE4A__
   // It's ok to use SSE4A instructions based on the -march option.
   #define MOZILLA_PRESUME_SSE4A 1
 #endif
 #ifdef __SSE4_1__
   // It's ok to use SSE4.1 instructions based on the -march option.
   #define MOZILLA_PRESUME_SSE4_1 1
 #endif
 #ifdef __SSE4_2__
   // It's ok to use SSE4.2 instructions based on the -march option.
   #define MOZILLA_PRESUME_SSE4_2 1
 #endif
 #ifdef HAVE_CPUID_H
   #define MOZILLA_SSE_HAVE_CPUID_DETECTION
 #endif
 #elif defined(_MSC_VER) && (defined(_M_IX86) || defined(_M_AMD64))
 #define MOZILLA_SSE_HAVE_CPUID_DETECTION
 #if defined(_M_IX86_FP)
 #if _M_IX86_FP >= 1
   // It's ok to use SSE instructions based on the /arch option
   #define MOZILLA_PRESUME_SSE
 #endif
 #if _M_IX86_FP >= 2
   // It's ok to use SSE2 instructions based on the /arch option
   #define MOZILLA_PRESUME_SSE2
 #endif
 #elif defined(_M_AMD64)
   // MSVC for AMD64 doesn't support MMX, so don't presume it here.
   // SSE is always available on AMD64.
   #define MOZILLA_PRESUME_SSE
   // SSE2 is always available on AMD64.
   #define MOZILLA_PRESUME_SSE2
 #endif
 #elif defined(__SUNPRO_CC) && (defined(__i386) || defined(__x86_64__))
 // Sun Studio on x86 or amd64
 #define MOZILLA_SSE_HAVE_CPUID_DETECTION
 #if defined(__x86_64__)
   // MMX is always available on AMD64.
   #define MOZILLA_PRESUME_MMX
   // SSE is always available on AMD64.
   #define MOZILLA_PRESUME_SSE
   // SSE2 is always available on AMD64.
   #define MOZILLA_PRESUME_SSE2
 #endif
 #endif
 namespace mozilla {
   namespace sse_private {
 #if defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #if !defined(MOZILLA_PRESUME_MMX)
     extern bool MFBT_DATA mmx_enabled;
 #endif
 #if !defined(MOZILLA_PRESUME_SSE)
     extern bool MFBT_DATA sse_enabled;
 #endif
 #if !defined(MOZILLA_PRESUME_SSE2)
     extern bool MFBT_DATA sse2_enabled;
 #endif
 #if !defined(MOZILLA_PRESUME_SSE3)
     extern bool MFBT_DATA sse3_enabled;
 #endif
 #if !defined(MOZILLA_PRESUME_SSSE3)
     extern bool MFBT_DATA ssse3_enabled;
 #endif
 #if !defined(MOZILLA_PRESUME_SSE4A)
     extern bool MFBT_DATA sse4a_enabled;
 #endif
 #if !defined(MOZILLA_PRESUME_SSE4_1)
     extern bool MFBT_DATA sse4_1_enabled;
 #endif
 #if !defined(MOZILLA_PRESUME_SSE4_2)
     extern bool MFBT_DATA sse4_2_enabled;
 #endif
 #endif
   }
 #if defined(MOZILLA_PRESUME_MMX)
 #define MOZILLA_MAY_SUPPORT_MMX 1
   inline bool supports_mmx() { return true; }
 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #if !(defined(_MSC_VER) && defined(_M_AMD64))
   // Define MOZILLA_MAY_SUPPORT_MMX only if we're not on MSVC for
   // AMD64, since that compiler doesn't support MMX.
 #define MOZILLA_MAY_SUPPORT_MMX 1
 #endif
   inline bool supports_mmx() { return sse_private::mmx_enabled; }
 #else
   inline bool supports_mmx() { return false; }
 #endif
 #if defined(MOZILLA_PRESUME_SSE)
 #define MOZILLA_MAY_SUPPORT_SSE 1
   inline bool supports_sse() { return true; }
 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #define MOZILLA_MAY_SUPPORT_SSE 1
   inline bool supports_sse() { return sse_private::sse_enabled; }
 #else
   inline bool supports_sse() { return false; }
 #endif
 #if defined(MOZILLA_PRESUME_SSE2)
 #define MOZILLA_MAY_SUPPORT_SSE2 1
   inline bool supports_sse2() { return true; }
 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #define MOZILLA_MAY_SUPPORT_SSE2 1
   inline bool supports_sse2() { return sse_private::sse2_enabled; }
 #else
   inline bool supports_sse2() { return false; }
 #endif
 #if defined(MOZILLA_PRESUME_SSE3)
 #define MOZILLA_MAY_SUPPORT_SSE3 1
   inline bool supports_sse3() { return true; }
 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #define MOZILLA_MAY_SUPPORT_SSE3 1
   inline bool supports_sse3() { return sse_private::sse3_enabled; }
 #else
   inline bool supports_sse3() { return false; }
 #endif
 #if defined(MOZILLA_PRESUME_SSSE3)
 #define MOZILLA_MAY_SUPPORT_SSSE3 1
   inline bool supports_ssse3() { return true; }
 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #define MOZILLA_MAY_SUPPORT_SSSE3 1
   inline bool supports_ssse3() { return sse_private::ssse3_enabled; }
 #else
   inline bool supports_ssse3() { return false; }
 #endif
 #if defined(MOZILLA_PRESUME_SSE4A)
 #define MOZILLA_MAY_SUPPORT_SSE4A 1
   inline bool supports_sse4a() { return true; }
 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #define MOZILLA_MAY_SUPPORT_SSE4A 1
   inline bool supports_sse4a() { return sse_private::sse4a_enabled; }
 #else
   inline bool supports_sse4a() { return false; }
 #endif
 #if defined(MOZILLA_PRESUME_SSE4_1)
 #define MOZILLA_MAY_SUPPORT_SSE4_1 1
   inline bool supports_sse4_1() { return true; }
 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #define MOZILLA_MAY_SUPPORT_SSE4_1 1
   inline bool supports_sse4_1() { return sse_private::sse4_1_enabled; }
 #else
   inline bool supports_sse4_1() { return false; }
 #endif
 #if defined(MOZILLA_PRESUME_SSE4_2)
 #define MOZILLA_MAY_SUPPORT_SSE4_2 1
   inline bool supports_sse4_2() { return true; }
 #elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
 #define MOZILLA_MAY_SUPPORT_SSE4_2 1
   inline bool supports_sse4_2() { return sse_private::sse4_2_enabled; }
 #else
   inline bool supports_sse4_2() { return false; }
 #endif
 }
 #endif /* !defined(mozilla_SSE_h_) */

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mozglue/build/SSE.h@97036ab72558 (annotated)

mozglue/build/SSE.h