The main issue being fixed here is that APCS targets handling a "byval align N"
parameter with N > 4 were miscounting what objects were where on the stack,
leading to FrameLowering setting the frame pointer incorrectly and clobbering
the stack.
But byval handling had grown over many years, and had multiple layers of cruft
trying to compensate for each other and calculate padding correctly. This only
really needs to be done once, in the HandleByVal function. Elsewhere should
just do what it's told by that call.
I also stripped out unnecessary APCS/AAPCS distinctions (now that Clang emits
byvals with the correct C ABI alignment), which simplified HandleByVal.
rdar://20095672
llvm-svn: 231959
Tail call optimisation was previously disabled on all targets other than
iOS5.0+. This enables the tail call optimisation on all Thumb 2 capable
platforms.
The test adjustments are to remove the IR hint "tail" to function invocation.
The tests were designed assuming that tail call optimisations would not kick in
which no longer holds true.
llvm-svn: 203575
