transcript of running demo_3f under gdb and disassembling resulting code

gistfile1.txt

% cargo run --example demo_3f
     Running `target/debug/examples/demo_3f`
; ModuleID = 'simple'

; Function Attrs: nounwind readnone
define double @thr(double) #0 {
entry:
  ret double 3.000000e+00
}

attributes #0 = { nounwind readnone }
An unknown error occurred

To learn more, run the command again with --verbose.
% gdb ./target/debug/examples/demo_3f
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Reading symbols from ./target/debug/examples/demo_3f...done.
warning: Missing auto-load scripts referenced in section .debug_gdb_scripts
of file /home/pnkfelix/Dev/Rust/lang-gc/llvm-rs/target/debug/examples/demo_3f
Use `info auto-load python-scripts [REGEXP]' to list them.
(gdb) r
Starting program: /home/pnkfelix/Dev/Rust/lang-gc/llvm-rs/target/debug/examples/demo_3f 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
; ModuleID = 'simple'

; Function Attrs: nounwind readnone
define double @thr(double) #0 {
entry:
  ret double 3.000000e+00
}

attributes #0 = { nounwind readnone }

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff7ff4000 in thr ()
(gdb) disassemble thr
Dump of assembler code for function thr:
=> 0x00007ffff7ff4000 <+0>:	movsd  xmm1,QWORD PTR ds:0xfffffffff7ff3000
   0x00007ffff7ff4009 <+9>:	movsd  QWORD PTR [rsp-0x8],xmm0
   0x00007ffff7ff400f <+15>:	movaps xmm0,xmm1
   0x00007ffff7ff4012 <+18>:	ret    
End of assembler dump.
(gdb)