Bug 184584 – [MIPS] Optimize generated JIT code using mips32r2 instructions

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Srdjan Lazarevic]

EXT and MFHC1 instructions from MIPSR2 implemented and used where it is possible.
Also, done some code size optimizations that were discovered in meantime.

[Srdjan Lazarevic]

Created attachment 337882 [details]
Patch

[EWS Watchlist]

Attachment 337882 [details] did not pass style-queue:


ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:241:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:242:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:243:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
Total errors found: 3 in 4 files


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

[Srdjan Lazarevic]

Can anyone take a look at this change?

[Mark Lam]

Comment on attachment 337882 [details]
Patch

I don't have much MIPS expertise but LGTM.  Someone who knows the MIPS instruction set should really review.

Also, would be better if you add some tests in testmasm.cpp that exercises your macro assembler functions.

[Srdjan Lazarevic]

Yusuke Suzuki, are you OK with the change?

[Srdjan Lazarevic]

Ping.

[Yusuke Suzuki]

Comment on attachment 337882 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=337882&action=review

The logic of the code looks good, but there are so much duplicate code. Can we clean up them?

> Source/JavaScriptCore/assembler/MacroAssemblerMIPS.h:2933
> +            if (!address.scale)
> +                m_assembler.addu(addrTempRegister, address.index, address.base);
> +            else {
> +                m_assembler.sll(addrTempRegister, address.index, address.scale);
> +                m_assembler.addu(addrTempRegister, addrTempRegister, address.base);
> +            }
> +            if (address.offset < -32768 || address.offset > 32767) {
> +                m_assembler.lui(immTempRegister, (address.offset + 0x8000) >> 16);
> +                m_assembler.addu(addrTempRegister, addrTempRegister, immTempRegister);
> +            }

This code pattern is so repeated. Can we extract this pattern to remove duplicate code?

> Source/JavaScriptCore/assembler/MacroAssemblerMIPS.h:2934
> +                m_assembler.swc1(src, addrTempRegister, address.offset);

Fix this indent.

[Srdjan Lazarevic]

Created attachment 339717 [details]
Patch

Clean up duplicate code.

[EWS Watchlist]

Attachment 339717 [details] did not pass style-queue:


ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:241:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:242:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:243:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
Total errors found: 3 in 4 files


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

[Yusuke Suzuki]

Comment on attachment 339717 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=339717&action=review

> Source/JavaScriptCore/assembler/MacroAssemblerMIPS.h:323
> +    void loadAddress(BaseIndex address, bool loadTrail = true)

Use `enum class` instead of `bool`. In this case, not using default parameter is better.
And `loadTrail` is a bit confusing. Maybe, `enum class LoadAddressMode { DontAddOffset, AddOffset };` would be more descriptive.

[Srdjan Lazarevic]

Created attachment 339958 [details]
Patch

'Enum class' instead 'bool', removed default parameter.

[EWS Watchlist]

Attachment 339958 [details] did not pass style-queue:


ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:241:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:242:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:243:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
Total errors found: 3 in 4 files


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

[Yusuke Suzuki]

Comment on attachment 339958 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=339958&action=review

> Source/JavaScriptCore/assembler/MacroAssemblerMIPS.h:117
> +        ScaleAndAddOffset,

I think this enum name is a bit misleading since `offset` is only added if `offset` is large / small enough.

[Yusuke Suzuki]

(In reply to Yusuke Suzuki from comment #13)
> Comment on attachment 339958 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=339958&action=review
> 
> > Source/JavaScriptCore/assembler/MacroAssemblerMIPS.h:117
> > +        ScaleAndAddOffset,
> 
> I think this enum name is a bit misleading since `offset` is only added if
> `offset` is large / small enough.

Maybe the other enum name would be fine. Like, `ScaleAndAddOffsetIfOffsetIsOutOfBounds`.

[Srdjan Lazarevic]

Created attachment 339960 [details]
Patch

Fixed. :)

[EWS Watchlist]

Attachment 339960 [details] did not pass style-queue:


ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:241:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:242:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
ERROR: Source/JavaScriptCore/assembler/MIPSAssembler.h:243:  enum members should use InterCaps with an initial capital letter or initial 'k' for C-style enums.  [readability/enum_casing] [4]
Total errors found: 3 in 4 files


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

[EWS Watchlist]

Comment on attachment 339958 [details]
Patch

Attachment 339958 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.webkit.org/results/7623156

New failing tests:
http/tests/security/XFrameOptions/x-frame-options-deny-multiple-clients.html

[EWS Watchlist]

Created attachment 339962 [details]
Archive of layout-test-results from ews107 for mac-sierra-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews107  Port: mac-sierra-wk2  Platform: Mac OS X 10.12.6

[WebKit Commit Bot]

Comment on attachment 339960 [details]
Patch

Clearing flags on attachment: 339960

Committed r231554: <https://trac.webkit.org/changeset/231554>

[Yusuke Suzuki]

Seems landed.

[Radar WebKit Bug Importer]

<rdar://problem/40651435>

[Guillaume Emont]

Comment on attachment 339958 [details]
Patch

Clearing r? flag as a variant of the patch landed in r231554.