Bug 59896 – Remove JmpSrc/JmpDst types.

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Gavin Barraclough]

The JmpSrc/JmpDst classes predate the MacroAssembler interface.  Having these object be per-assembler in unhelpful, causes unnecessary code duplication, and prevents the AssemblerBuffer from providing a richer type for labels.  The limited semantic meaning that they did convey is undermined by the manner in which their meanings have been overloaded (use of JmpSrc for Call, JmpDst for data labels).

Jumps on ARMv7 have had additional information added to the object via the ARMv7 JmpSrc.  This data should probably be in the instruction stream.  This patch does not fix the problem, and moves the data (ifdefed) to AbstractMacroAssembler::Jump (which is effectively where it was before!).  This at least closes the hole such that no further data may be added to JmpSrc, but this is unfortunate, and should be cleaned up.

[Gavin Barraclough]

Created attachment 91847 [details]
The patch

[WebKit Review Bot]

Attachment 91847 [details] did not pass style-queue:

Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/JavaScriptCore/ChangeLog', u'Source..." exit_code: 1

Source/JavaScriptCore/assembler/X86Assembler.h:1197:  jmp_r is incorrectly named. Don't use underscores in your identifier names.  [readability/naming] [4]
Source/JavaScriptCore/assembler/AssemblerBuffer.h:40:  Code inside a namespace should not be indented.  [whitespace/indent] [4]
Total errors found: 2 in 14 files


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

[Sam Weinig]

Comment on attachment 91847 [details]
The patch

Please add a comment about why 2^32-1 is enough.

[Gavin Barraclough]

Fixed in r85432.

[Chao-ying Fu]

Hi Gavin,

  For MIPS build, we need to switch the order of header files to get it compiled.  Thanks!

Regards,
Chao-ying

fu@debian:/disk/fu/dev/WebKit/Source/JavaScriptCore/assembler$ svn diff
Index: MacroAssemblerMIPS.h
===================================================================
--- MacroAssemblerMIPS.h        (revision 85498)
+++ MacroAssemblerMIPS.h        (working copy)
@@ -29,8 +29,8 @@

 #if ENABLE(ASSEMBLER) && CPU(MIPS)

+#include "MIPSAssembler.h"
 #include "AbstractMacroAssembler.h"
-#include "MIPSAssembler.h"

 namespace JSC {

[石梦军]

is exist some reason for using char* to replace void* in the getRelocatedAddress function of the sh4assembler.h file?