Bug 43089 – Cleanup JIT related switched in Platform.h

• Status: RESOLVED
• Resolution: FIXED
• Component: JavaScriptCore

[Gavin Barraclough]

The code the enable to JIT checks every permutation of platform & OS individually, but now the JIT is enabled on the majority much all x86/x86-64/ARM/MIPS systems.  It should be cleaner to just enable by default on these platforms, and explicitly disable on configs that don't aren't supported.

Also, rename ENABLE_JIT_OPTIMIZE_MOD to ENABLE_JIT_USE_SOFT_MODULO.  I always find this confusing since enabling this "optimization" would be possible, but would be a regression on x86/x86-64 systems!  I think it's clearer to reserve "JIT_OPTIMIZE" for compiler technologies applicable to all platforms, and make a more optional behaviour like this a "USE".

[Gavin Barraclough]

Created attachment 62764 [details]
The patch

[WebKit Review Bot]

Attachment 62764 [details] did not pass style-queue:

Failed to run "['WebKitTools/Scripts/check-webkit-style']" exit_code: 1
JavaScriptCore/jit/ExecutableAllocator.h:202:  Missing space after ,  [whitespace/comma] [3]
JavaScriptCore/jit/ExecutableAllocator.h:203:  Missing space after ,  [whitespace/comma] [3]
JavaScriptCore/wtf/Platform.h:923:  Missing space after ,  [whitespace/comma] [3]
JavaScriptCore/wtf/Platform.h:930:  Missing space after ,  [whitespace/comma] [3]
Total errors found: 4 in 8 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Gavin Barraclough]

fixed in r64176.

[Chao-ying Fu]

There is a typo in ExecutableAllocator.h for MIPS.  We need to use ! for the macro to test if GCC is < 4.4.3.  Thanks!

Ex:
Index: ExecutableAllocator.h
===================================================================
--- ExecutableAllocator.h       (revision 64473)
+++ ExecutableAllocator.h       (working copy)
@@ -200,7 +200,7 @@
     static void cacheFlush(void* code, size_t size)
     {
 #if COMPILER(GCC) && GCC_VERSION_AT_LEAST(4,3,0)
-#if WTF_MIPS_ISA_REV(2) && GCC_VERSION_AT_LEAST(4,4,3)
+#if WTF_MIPS_ISA_REV(2) && !GCC_VERSION_AT_LEAST(4,4,3)
         int lineSize;
         asm("rdhwr %0, $1" : "=r" (lineSize));
         //

Regards,
Chao-ying

[Gavin Barraclough]

Ooops, sorry Chao-ying, will fix this.  Thanks! G.

[Gavin Barraclough]

Fix landed in r64619.