Fix compiler warnings.
x86/x64: Avoid use of SAHF instruction.
Fix check for reuse of SCEV results in FORL.
FFI: Fix pseudo type conversions for type punning.
FFI: Allow non-scalar cdata to be compared for equality by address.
Correct fix for reuse of SCEV results in FORL.
Fix top slot calculation for snapshots with continuations.
FFI: Fix cdata equality comparison against strings.
FFI: Fix cdata equality comparison against other Lua types.
PPC: Don't use mcrxr on PPE.
x64: Allow building with LUAJIT_USE_SYSMALLOC and LUAJIT_USE_VALGRIND.

Valgrind 3.9 killed MAP_32BIT support. Ugh. So now we have to rely on
undocumented behavior where Valgrind always allocates from the bottom
of memory. Alas, such a binary won't run properly without Valgrind.
Prevent adding side traces for stack checks.
Prevent GC estimate miscalculation due to buffer growth.
Add PS Vita port.

Thanks to Anton Stenmark.
FFI: Another fix for cdata equality comparisons.
x64: Workaround for MSVC build issue.
Fix frame traversal while searching for error function.
Fix FOLD rule for STRREF of SNEW.
FFI: Fix recording of indexing a struct pointer ctype object itself.
Fix FOLD rule for string.sub(s, ...) == k.