ConcatCopy generates movdqa copies for unaligned reference

Summary

System Information

Linux/x86-64, Main branch as of ccc843f9

Steps to reproduce

cd compiler
make cycle
mv ppcx64 $HOME/bin/ppcx1
make FPC=$HOME/bin/ppcx1 LLVM=1 OPT="-O- -gw" clean all
mv ppcx64 $HOME/bin/ppcx1llvm
cd ../rtl/linux
make FPC=$HOME/bin/ppcx1llvm

What is the current bug behavior?

$ run
Starting program: /home/jmaebe/bin/ppcx2llgv -Fi../inc -Fi../x86_64 -Fi../unix -Fix86_64 -FE. -FU../../rtl/units/x86_64-linux -Cg -Fl/usr/lib/gcc/x86_64-linux-gnu/7 -dx86_64  -Us -Sg system.pp

Program received signal SIGSEGV, Segmentation fault.
0x00000000004c7f62 in GETCOPY (this=0x134d7e8) at aasmtai.pas:3135
$ x/i $pc-20
3135                p.oper[i]^:=oper[i]^;
   0x4c7f4e <GETCOPY+110>:      mov    -0x14(%rbp),%edx
   0x4c7f51 <GETCOPY+113>:      mov    0x40(%rax,%rdx,8),%rax
   0x4c7f56 <GETCOPY+118>:      mov    -0x8(%rbp),%rdx
   0x4c7f5a <GETCOPY+122>:      mov    -0x14(%rbp),%ecx
   0x4c7f5d <GETCOPY+125>:      mov    0x40(%rdx,%rcx,8),%rdx
=> 0x4c7f62 <GETCOPY+130>:      movdqa (%rdx),%xmm0
   0x4c7f66 <GETCOPY+134>:      movdqa 0x10(%rdx),%xmm1
   0x4c7f6b <GETCOPY+139>:      movdqa %xmm0,(%rax)
   0x4c7f6f <GETCOPY+143>:      movdqa %xmm1,0x10(%rax)
   0x4c7f74 <GETCOPY+148>:      mov    -0x8(%rbp),%rdx
$ p/x $rdx
$2 = 0x1498a38

What is the expected (correct) behavior?

ConcatCopy should not use movdqa here, but movdqu. I don't know why it thinks that reference will be 16 bytes aligned.

Other remarks

Unrelated to this issue: GetRefAlignment should use current_procinfo.framepointer instead of NR_RBP. RBP could be used as a register variable in functions that use the stack pointer as frame pointer.