Changeset 37235 in webkit for trunk/JavaScriptCore/VM

Timestamp:

Oct 3, 2008, 4:11:55 AM (17 years ago)

Author:

[email protected]

Message:

Replace SSE3 check with an SSE2 check, and implement SSE2 check on windows.

Reviewed by Maciej Stachowiak

5.6% win on SunSpider on windows.

File:

• trunk/JavaScriptCore/VM/CTI.cpp (modified) (6 diffs)

trunk/JavaScriptCore/VM/CTI.cpp

@@ -43 +43 @@
 
 #if PLATFORM(MAC)
-bool isSSE3Present()
-{
-    struct SSE3Check {
-        SSE3Check()
+bool isSSE2Present()
+{
+    return true; // All X86 Macs are guaranteed to support at least SSE2
+}
+#else COMPILER(MSVC)
+bool isSSE2Present()
+{
+    static const int SSE2FeatureBit = 1 << 26;
+    struct SSE2Check {
+        SSE2Check()
         {
-            int hasSSE3 = 0;
-            size_t length = sizeof(hasSSE3);
-            int error = sysctlbyname("hw.optional.sse3", &hasSSE3, &length, NULL, 0);
-            present = hasSSE3 && !error;
+            int flags;
+#if COMPILER(MSVC)
+            _asm {
+                mov eax, 1 // cpuid function 1 gives us the standard feature set
+                cpuid;
+                mov flags, edx;
+            }
+#else
+            flags = 0;
+            // FIXME: Add GCC code to do above asm
+#endif
+            present = (flags & SSE2FeatureBit) != 0;
         }
         bool present;
     };
-    static SSE3Check check;
+    static SSE2Check check;
     return check.present;
-}
-#else
-bool isSSE3Present()
-{
-    return false;
 }
 #endif
@@ -672 +681 @@
     emitGetArg(src2, X86::edx);
 
-    if (types.second().isReusable() && isSSE3Present()) {
+    if (types.second().isReusable() && isSSE2Present()) {
         ASSERT(types.second().mightBeNumber());
 
@@ -719 +728 @@
         m_jit.link(op2imm, m_jit.label());
         emitJumpSlowCaseIfNotImmNum(X86::eax, i);
-    } else if (types.first().isReusable() && isSSE3Present()) {
+    } else if (types.first().isReusable() && isSSE2Present()) {
         ASSERT(types.first().mightBeNumber());
 
@@ -790 +799 @@
     emitPutResult(dst);
 
-    if (types.second().isReusable() && isSSE3Present()) {
+    if (types.second().isReusable() && isSSE2Present()) {
         m_jit.link(wasJSNumberCell2, m_jit.label());
         m_jit.link(wasJSNumberCell2b, m_jit.label());
     }
-    else if (types.first().isReusable() && isSSE3Present()) {
+    else if (types.first().isReusable() && isSSE2Present()) {
         m_jit.link(wasJSNumberCell1, m_jit.label());
         m_jit.link(wasJSNumberCell1b, m_jit.label());
@@ -804 +813 @@
     X86Assembler::JmpDst here = m_jit.label();
     m_jit.link(iter->from, here);
-    if (types.second().isReusable() && isSSE3Present()) {
+    if (types.second().isReusable() && isSSE2Present()) {
         if (!types.first().definitelyIsNumber()) {
             m_jit.link((++iter)->from, here);
@@ -814 +823 @@
         }
         m_jit.link((++iter)->from, here);
-    } else if (types.first().isReusable() && isSSE3Present()) {
+    } else if (types.first().isReusable() && isSSE2Present()) {
         if (!types.first().definitelyIsNumber()) {
             m_jit.link((++iter)->from, here);