qsimd_p.h: Reorganize and simplify the x86 intrinsics #includes

All of our compilers support #include <immintrin.h>, so we don't need
the legacy code that includes the earlier versions.

Change-Id: I938b024e38bf4aac9154fffd14f80214d1d744c8
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

1 files changed, 28 insertions, 68 deletions

diff --git a/src/corelib/tools/qsimd_p.h b/src/corelib/tools/qsimd_p.h
index fafc3e37b0..eb56b31348 100644
--- a/src/corelib/tools/qsimd_p.h
+++ b/src/corelib/tools/qsimd_p.h
@@ -177,55 +177,37 @@
 #  define QT_FUNCTION_TARGET(x)
 #endif
 
-#if defined(Q_CC_MSVC) && (defined(_M_AVX) || defined(__AVX__))
-// Visual Studio defines __AVX__ when /arch:AVX is passed, but not the earlier macros
-// See: https://msdn.microsoft.com/en-us/library/b0084kay.aspx
-// SSE2 is handled by _M_IX86_FP below
-#  define __SSE3__ 1
-#  define __SSSE3__ 1
-// no Intel CPU supports SSE4a, so don't define it
-#  define __SSE4_1__ 1
-#  define __SSE4_2__ 1
-#  ifndef __AVX__
-#    define __AVX__ 1
-#  endif
-#endif
-
-// SSE intrinsics
-#if defined(__SSE2__) || (defined(QT_COMPILER_SUPPORTS_SSE2) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS))
-#if defined(QT_LINUXBASE)
-/// this is an evil hack - the posix_memalign declaration in LSB
-/// is wrong - see http://bugs.linuxbase.org/show_bug.cgi?id=2431
-#  define posix_memalign _lsb_hack_posix_memalign
-#  include <emmintrin.h>
-#  undef posix_memalign
-#else
-#  include <emmintrin.h>
-#endif
-#if defined(Q_CC_MSVC) && (defined(_M_X64) || _M_IX86_FP >= 2)
-#  define __SSE__ 1
-#  define __SSE2__ 1
-#endif
-#endif
+#ifdef Q_PROCESSOR_X86
+/* -- x86 intrinsic support -- */
 
-// SSE3 intrinsics
-#if defined(__SSE3__) || (defined(QT_COMPILER_SUPPORTS_SSE3) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS))
-#include <pmmintrin.h>
-#endif
+#  if defined(Q_CC_MSVC) && (defined(_M_X64) || _M_IX86_FP >= 2)
+// MSVC doesn't define __SSE2__, so do it ourselves
+#    define __SSE__                         1
+#    define __SSE2__                        1
+#  endif
 
-// SSSE3 intrinsics
-#if defined(__SSSE3__) || (defined(QT_COMPILER_SUPPORTS_SSSE3) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS))
-#include <tmmintrin.h>
-#endif
+#  ifdef __SSE2__
+// #include the intrinsics
+#    include <immintrin.h>
+#  endif
 
-// SSE4.1 intrinsics
-#if defined(__SSE4_1__) || (defined(QT_COMPILER_SUPPORTS_SSE4_1) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS))
-#include <smmintrin.h>
-#endif
+#  if defined(Q_CC_GNU) && !defined(Q_CC_INTEL)
+// GCC 4.4 and Clang 2.8 added a few more intrinsics there
+#    include <x86intrin.h>
+#  endif
 
-// SSE4.2 intrinsics
-#if defined(__SSE4_2__) || (defined(QT_COMPILER_SUPPORTS_SSE4_2) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS))
-#include <nmmintrin.h>
+#  if defined(Q_CC_MSVC) && (defined(_M_AVX) || defined(__AVX__))
+// Visual Studio defines __AVX__ when /arch:AVX is passed, but not the earlier macros
+// See: https://msdn.microsoft.com/en-us/library/b0084kay.aspx
+#    define __SSE3__                        1
+#    define __SSSE3__                       1
+// no Intel CPU supports SSE4a, so don't define it
+#    define __SSE4_1__                      1
+#    define __SSE4_2__                      1
+#    ifndef __AVX__
+#      define __AVX__                       1
+#    endif
+#  endif
 
 #  if defined(__SSE4_2__) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS) && (defined(Q_CC_INTEL) || defined(Q_CC_MSVC))
 // POPCNT instructions:
@@ -233,13 +215,8 @@
 // (but neither MSVC nor the Intel compiler define this macro)
 #    define __POPCNT__                      1
 #  endif
-#endif
 
 // AVX intrinsics
-#if defined(__AVX__) || (defined(QT_COMPILER_SUPPORTS_AVX) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS))
-// immintrin.h is the ultimate header, we don't need anything else after this
-#include <immintrin.h>
-
 #  if defined(__AVX__) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS) && (defined(Q_CC_INTEL) || defined(Q_CC_MSVC))
 // AES, PCLMULQDQ instructions:
 // All processors that support AVX support AES, PCLMULQDQ
@@ -255,11 +232,6 @@
 #    define __F16C__                        1
 #    define __RDRND__                       1
 #  endif
-#endif
-
-#if defined(__AES__) || defined(__PCLMUL__) || (defined(QT_COMPILER_SUPPORTS_AES) && defined(QT_COMPILER_SUPPORTS_SIMD_ALWAYS))
-#  include <wmmintrin.h>
-#endif
 
 #define QT_FUNCTION_TARGET_STRING_SSE2      "sse2"
 #define QT_FUNCTION_TARGET_STRING_SSE3      "sse3"
@@ -288,19 +260,7 @@
 #define QT_FUNCTION_TARGET_STRING_RDSEED        "rdseed"
 #define QT_FUNCTION_TARGET_STRING_SHA           "sha"
 
-// other x86 intrinsics
-#if defined(Q_PROCESSOR_X86) && ((defined(Q_CC_GNU) && (Q_CC_GNU >= 404)) \
-    || (defined(Q_CC_CLANG) && (Q_CC_CLANG >= 208)) \
-    || defined(Q_CC_INTEL))
-#  define QT_COMPILER_SUPPORTS_X86INTRIN
-#  ifdef Q_CC_INTEL
-// The Intel compiler has no <x86intrin.h> -- all intrinsics are in <immintrin.h>;
-#    include <immintrin.h>
-#  else
-// GCC 4.4 and Clang 2.8 added a few more intrinsics there
-#    include <x86intrin.h>
-#  endif
-#endif
+#endif  /* Q_PROCESSOR_X86 */
 
 // Clang compiler fix, see http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20160222/151168.html
 // This should be tweaked with an "upper version" of clang once we know which release fixes the