It isn't clear from the names of the JSC MacroAssembler function load8Signed() and load16Signed() as to how many bits to sign extend. The code expects sign extending to 32 bits, but the ARM64 version was sign extending to 64 bits (https://bugs.webkit.org/show_bug.cgi?id=138390). The names of these function should reflect the number of bits they sign extend out to.
Created attachment 249627 [details]
Patch for lnding, already reviewed.
Committed r182098: <http://trac.webkit.org/changeset/182098>