create symbols for the various SSE values

add GCC check for SSSE3, and assume it is ordered SSE3 < SSSE3 < SSE4



git-svn-id: http://skia.googlecode.com/svn/trunk@4421 2bbb7eff-a529-9590-31e7-b0007b416f81

2 files changed, 32 insertions, 10 deletions

diff --git a/include/core/SkChecksum.h b/include/core/SkChecksum.h
index ab88cbc01a..020403f607 100644
--- a/include/core/SkChecksum.h
+++ b/include/core/SkChecksum.h
@@ -59,11 +59,27 @@ inline uint32_t SkComputeChecksum32(const uint32_t* ptr, size_t size) {
     SkASSERT(SkIsAlign4(size));
     SkASSERT(SkIsAlign4((intptr_t)ptr));
 
-    const uint32_t* stop = ptr + (size >> 2);
-    uint32_t result = 0;
-    while (ptr < stop) {
-        SkCHECKSUM_MASH(result, *ptr);
-        ptr++;
+    uint32_t result;
+    
+    if (8 == sizeof(void*)) {
+        uint64_t result8 = 0;
+        if (size & 4) {
+            result8 = *ptr++;   // initial 32bit value
+        }
+        const uint64_t* ptr8 = (const uint64_t*)ptr;
+        const uint64_t* stop = ptr8 + (size >> 3);
+        while (ptr8 < stop) {
+            SkCHECKSUM_MASH(result8, *ptr8);
+            ptr8++;
+        }
+        result = static_cast<uint32_t>(result8 ^ (result8 >> 32));
+    } else {
+        result = 0;
+        const uint32_t* stop = ptr + (size >> 2);
+        while (ptr < stop) {
+            SkCHECKSUM_MASH(result, *ptr);
+            ptr++;
+        }
     }
     return result;
 }
diff --git a/include/core/SkPreConfig.h b/include/core/SkPreConfig.h
index 22601a7e80..812e446b13 100644
--- a/include/core/SkPreConfig.h
+++ b/include/core/SkPreConfig.h
@@ -103,14 +103,20 @@
 //////////////////////////////////////////////////////////////////////
 
 /**
- *  If defined, SK_CPU_SSE_LEVEL should be set to [2,3,41,42]. On non-intel CPU,
- *  this should be undefined.
+ *  If defined, SK_CPU_SSE_LEVEL should be set to the highest supported level.
+ *  On non-intel CPU this should be undefined.
  */
+#define SK_CPU_LEVEL_SSE2_VALUE     20
+#define SK_CPU_LEVEL_SSE3_VALUE     30
+#define SK_CPU_LEVEL_SSSE3_VALUE    31
+
 #ifndef SK_CPU_SSE_LEVEL
-    #ifdef __SSE3__
-        #define SK_CPU_SSE_LEVEL    3
+    #if defined(__SSSE3__)
+        #define SK_CPU_SSE_LEVEL    SK_CPU_LEVEL_SSSE3_VALUE
+    #elif defined(__SSE3__)
+        #define SK_CPU_SSE_LEVEL    SK_CPU_LEVEL_SSE3_VALUE
     #elif defined(__SSE2__)
-        #define SK_CPU_SSE_LEVEL    2
+        #define SK_CPU_SSE_LEVEL    SK_CPU_LEVEL_SSE2_VALUE
     #endif
 #endif