Changeset 43789 in webkit for trunk/JavaScriptCore/assembler/MacroAssemblerX86Common.h

Timestamp:

May 15, 2009, 3:40:11 PM (16 years ago)

Author:

[email protected]

Message:

2009-05-15 Gavin Barraclough <​[email protected]>

Reviewed by Oliver Hunt.

Looking like MSVC doesn't like static variables in inline methods?
Make the state of the SSE2 check a static variable on the class
MacroAssemblerX86Common as a speculative build fix for Windows.

• assembler/MacroAssemblerX86Common.h: (JSC::MacroAssemblerX86Common::convertInt32ToDouble): (JSC::MacroAssemblerX86Common::branchDouble): (JSC::MacroAssemblerX86Common::branchTruncateDoubleToInt32): (JSC::MacroAssemblerX86Common::isSSE2Present): (JSC::MacroAssemblerX86Common::):
• jit/JIT.cpp:

File:

• trunk/JavaScriptCore/assembler/MacroAssemblerX86Common.h (modified) (4 diffs)

trunk/JavaScriptCore/assembler/MacroAssemblerX86Common.h

@@ -328 +328 @@
     void convertInt32ToDouble(RegisterID src, FPRegisterID dest)
     {
+        ASSERT(isSSE2Present());
         m_assembler.cvtsi2sd_rr(src, dest);
     }
@@ -333 +334 @@
     Jump branchDouble(DoubleCondition cond, FPRegisterID left, FPRegisterID right)
     {
+        ASSERT(isSSE2Present());
         m_assembler.ucomisd_rr(right, left);
         return Jump(m_assembler.jCC(x86Condition(cond)));
@@ -343 +345 @@
     Jump branchTruncateDoubleToInt32(FPRegisterID src, RegisterID dest)
     {
+        ASSERT(isSSE2Present());
         m_assembler.cvttsd2si_rr(src, dest);
         return branch32(Equal, dest, Imm32(0x80000000));
@@ -707 +710 @@
     friend class MacroAssemblerX86;
 
-#if PLATFORM(X86_64)
-#ifndef NDEBUG
-    static bool isSSE2Present() { return true; }
+#if PLATFORM(X86)
+#if PLATFORM(MAC)
+
+    // All X86 Macs are guaranteed to support at least SSE2,
+    static bool isSSE2Present()
+    {
+        return true;
+    }
+
+#else // PLATFORM(MAC)
+
+    enum SSE2CheckState {
+        NotCheckedSSE2,
+        HasSSE2,
+        NoSSE2
+    };
+
+    static bool isSSE2Present()
+    {
+        if (s_sse2CheckState == NotCheckedSSE2) {
+            // Default the flags value to zero; if the compiler is
+            // not MSVC or GCC we will read this as SSE2 not present.
+            int flags = 0;
+#if COMPILER(MSVC)
+            _asm {
+                mov eax, 1 // cpuid function 1 gives us the standard feature set
+                cpuid;
+                mov flags, edx;
+            }
+#elif COMPILER(GCC)
+            asm (
+                 "movl $0x1, %%eax;"
+                 "pushl %%ebx;"
+                 "cpuid;"
+                 "popl %%ebx;"
+                 "movl %%edx, %0;"
+                 : "=g" (flags)
+                 :
+                 : "%eax", "%ecx", "%edx"
+                 );
 #endif
-#else
+            static const int SSE2FeatureBit = 1 << 26;
+            s_sse2CheckState = (flags & SSE2FeatureBit) ? HasSSE2 : NoSSE2;
+        }
+        // Only check once.
+        ASSERT(s_sse2CheckState != NotCheckedSSE2);
+
+        return s_sse2CheckState == HasSSE2;
+    }
+    
+    static SSE2CheckState s_sse2CheckState;
+
+#endif // PLATFORM(MAC)
+#elif !defined(NDEBUG) // PLATFORM(X86)
+
+    // On x86-64 we should never be checking for SSE2 in a non-debug build,
+    // but non debug add this method to keep the asserts above happy.
     static bool isSSE2Present()
     {
-#if PLATFORM(MAC)
-        // All X86 Macs are guaranteed to support at least SSE2
         return true;
-#else
-        static const int SSE2FeatureBit = 1 << 26;
-        struct SSE2Check {
-            SSE2Check()
-            {
-                int flags;
-#if COMPILER(MSVC)
-                _asm {
-                    mov eax, 1 // cpuid function 1 gives us the standard feature set
-                    cpuid;
-                    mov flags, edx;
-                }
-#elif COMPILER(GCC)
-                asm (
-                     "movl $0x1, %%eax;"
-                     "pushl %%ebx;"
-                     "cpuid;"
-                     "popl %%ebx;"
-                     "movl %%edx, %0;"
-                     : "=g" (flags)
-                     :
-                     : "%eax", "%ecx", "%edx"
-                     );
-#else
-                flags = 0;
-#endif
-                present = (flags & SSE2FeatureBit) != 0;
-            }
-            bool present;
-        };
-        static SSE2Check check;
-        return check.present;
-#endif // !PLATFORM(MAC)
-    }
+    }
+
 #endif
 };