Backends don't support this yet. They would have to move to the swifterror
register before the tail call to make sure it is live-in to the call.
rdar://30495920
llvm-svn: 294982
Functions that have a dynamic alloca require a base register which is defined to
be X19 on AArch64 and r6 on ARM. We have defined the swifterror register to be
the same register. Use a different callee save register for swifterror instead:
X21 on AArch64
R8 on ARM
rdar://30433803
llvm-svn: 294551
For example we were producing
push {r8, r10, r11, r4, r5, r7, lr}
This is misleading (r4, r5 and r7 are actually pushed before the rest), and
other components (stack folding recently) often forget to deal with the extra
complexity coming from the different order, leading to miscompiles. Finally, we
warn about our own code in -no-integrated-as mode without this, which is really
not a good idea.
Fixed usage of std::sort so that we (hopefully) use instantiations that
actually exist in GCC 4.8.
llvm-svn: 286881
For example we were producing
push {r8, r10, r11, r4, r5, r7, lr}
This is misleading (r4, r5 and r7 are actually pushed before the rest), and
other components (stack folding recently) often forget to deal with the extra
complexity coming from the different order, leading to miscompiles. Finally, we
warn about our own code in -no-integrated-as mode without this, which is really
not a good idea.
llvm-svn: 286866
The code used llvm basic block predecessors to decided where to insert phi
nodes. Instruction selection can and will liberally insert new machine basic
block predecessors. There is not a guaranteed one-to-one mapping from pred.
llvm basic blocks and machine basic blocks.
Therefore the current approach does not work as it assumes we can mark
predecessor machine basic block as needing a copy, and needs to know the set of
all predecessor machine basic blocks to decide when to insert phis.
Instead of computing the swifterror vregs as we select instructions, propagate
them at the end of instruction selection when the MBB CFG is complete.
When an instruction needs a swifterror vreg and we don't know the value yet,
generate a new vreg and remember this "upward exposed" use, and reconcile this
at the end of instruction selection.
This will only happen if the target supports promoting swifterror parameters to
registers and the swifterror attribute is used.
rdar://28300923
llvm-svn: 283617