1243815 - Baldr: Put hard limits to the number of sigs/args/imports etc.

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, defect)

Comment 1

[Benjamin Bouvier [:bbouvier] (inactive)]

Attachment: hardlimits.patch

I checked DeadTrigger2, maximum number of arguments per function is 17, so 128 should be enough for everybody.

Comment 2

[Luke Wagner [:luke]]

Comment on attachment 8713301 [details] [diff] [review]
hardlimits.patch

Review of attachment 8713301 [details] [diff] [review]:
-----------------------------------------------------------------

Nice, thanks!

::: js/src/asmjs/AsmJS.cpp
@@ -1674,5 @@
>          return sigMap_.add(p, &mg_.sig(*sigIndex), *sigIndex);
>      }
>  
> -    // ModuleGeneratorData limits:
> -    static const unsigned MaxSigs    =   4 * 1024;

Good idea sharing these limits!

::: js/src/asmjs/Wasm.cpp
@@ +393,5 @@
>      if (!d.readVarU32(&numDecls))
>          return Fail(cx, d, "expected number of declarations");
>  
> +    if (numDecls > MaxFuncs)
> +        return Fail(cx, d, "too many function declarations");

Let's just say "too many functions" (since num-decls = num-funcs).

::: js/src/asmjs/WasmBinary.h
@@ +32,5 @@
> +static const unsigned MaxSigs        =   4 * 1024;
> +static const unsigned MaxFuncs       = 512 * 1024;
> +static const unsigned MaxImports     =   4 * 1024;
> +static const unsigned MaxExports     =   4 * 1024;
> +static const unsigned MaxArgsPerFunc = 128;

I can imagine weird generated cases arising from codegen where the number of args could be quite a lot.  How about we bump this to 4k as well?

Comment 3

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/9e8f89a81569

Comment 4

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/9e8f89a81569