Bug 131532 – [sh4] LLINT is broken

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

[Julien Brianceau]

sh4 backend of LLINT is broken since C stack merge.
Specific parts are missing since http://trac.webkit.org/changeset/167094 too.

[Julien Brianceau]

Created attachment 229122 [details]
Fix sh4 LLINT

[Mark Lam]

Comment on attachment 229122 [details]
Fix sh4 LLINT

View in context: https://bugs.webkit.org/attachment.cgi?id=229122&action=review

> Source/JavaScriptCore/offlineasm/instructions.rb:296
> +    "alignFormova",

nit: This looks weird.  I suggest either renaming this to alignformova, or alignForMova or alignForMovA.

[Julien Brianceau]

Created attachment 229134 [details]
Fix sh4 LLINT (with consistent letter casing)

[Mark Lam]

Comment on attachment 229134 [details]
Fix sh4 LLINT (with consistent letter casing)

r=me

[Julien Brianceau]

Committed r167127: <http://trac.webkit.org/changeset/167127>

[Michael Saboff]

Comment on attachment 229134 [details]
Fix sh4 LLINT (with consistent letter casing)

View in context: https://bugs.webkit.org/attachment.cgi?id=229134&action=review

> Source/JavaScriptCore/llint/LowLevelInterpreter.asm:721
> +        mova _relativePCBase, t0
> +        move t0, pcBase

Why can't you just mova _relativePCBase directly into pcBase?

> Source/JavaScriptCore/offlineasm/sh4.rb:1032
> +            $asm.puts ".balign 4"

If the .balign has to fill, is the '0' fill going to be a nop?  You may want to explicitly mention that with a comment.

[Julien Brianceau]

(In reply to comment #6)
> Why can't you just mova _relativePCBase directly into pcBase?
Unfortunately, r0 is the only allowed dest register for the mova opcode.

> If the .balign has to fill, is the '0' fill going to be a nop?  You may want to explicitly mention that with a comment.
Yes, as the .balign directive is put in a section containing code, no-op instructions are used as fill value instead of 0.


I found a way to use SubImmediates with sh4 const pool, so the sh4 arch can share the arm path for setEntryAddress. I'm going to file a new bug with this implementation, and I'll add a comment for .balign in it.

[Julien Brianceau]

Created bugzilla: https://bugs.webkit.org/show_bug.cgi?id=131608