Javascript:SpiderMonkey:OdinMonkey

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Add stack-walking support for asm.js code so that asm.js functions show up in:
- The builtin FF profiler (bug 947996)
- Error.stack.
Standardize then implement SIMD extensions to JS (bug 894105) and then incorporate into asm.js
Land experimental SharedArrayBuffer (pref'd off, bug 933001) and use this to add experimental pthreads support to Emscripten and evaluate on threaded codebases in preparation for a standards proposal.

Reevaluate throughput now that we have float32: When we are >2x native, why? Any more categorical fixes (other than SIMD)?
Remove parsing limitations associated with huge JS files:
- Fix lazy-parsing/decompression memory-spike and performance hit for huge js files (bug 938385).
- Remove num-locals (bug 916612) and num-lines (bug 916564) parser limits.
Mitigate 32-bit OOM problems: (bug 865959)
Add && and || to asm.js to avoid sub-optimal control flow (bug 919052).
Add missing math constants (bug 878488)
Make the asm.js informative console messages not show up as "Error:"

Experiment with using LLVM as the compiler backend for asm.js code.
Compress asm.js cache entries
Further improve load-time:
- Start general JS parsing before the entire JS script has completed downloading so that asm.js compilation can overlap
- asm.js parser: Avoid building an intermediate parse tree; type check during recursive descent bug 854061
Improve heap access performance : bug 865516, bug 865523, bug 869606, bug 870743, bug 897425
Further improve FFI calls : bug 882399, bug 886411, also stop spilling non-volatile registers
Improve x86/ARM asm.js-to-asm.js ABI : bug 861785
Extend the asm.js signal handler tricks to:
- Remove stack overflow checks
- Remove idiv branching
- Remove double-to-int conversion branching (see also bug 818750)

Extend asm.js to better support dynamically linking asm.js modules (a mutable, callable array argument to asm.js module, like the PLT)
Add enough try/catch to asm.js to allow compilation of C++ exceptions using the zero-cost implementation strategy
Add DataView to avoid the alignment mask on asm.js heap accesses (this is mostly a problem of DataView being slow in all browsers)

ArrayBuffer.prototype.resize (bug 927182): to allow growable heap
ArrayBuffer.prototype.discard (bug 855669): to allow madvise(DONTNEED)
FunctionPromise: bug 854627
Typed Objects: (Typed Objects)
- This feature comes with float32/uint64/int64 value types, which would be useful as scalar types in asm.js.
- Formalize Typed Object "class declarations" in asm.js which could make asm.js a target for JVM/CLR/TypeScript (and allow these languages to reuse the builtin JS GC)

Credit to John Howard