[Bug middle-end/81478] By default, GCC emits a function call for complex multiplication, should partially inline that

["smcallis at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81478

--- Comment #6 from Sean McAllister <smcallis at gmail dot com> ---
FWIW, it seems the compute, check, re-compute if necessary is what clang does. 
Rather than "setp %al" and "jne" on that, they just use the "jp" instruction
directly after ucomiss:

   0x00000000004005d5 <+133>:   subss  %xmm6,%xmm0          ; compute real part
   0x00000000004005d9 <+137>:   addss  %xmm4,%xmm5          ; compute imaginary
part
   0x00000000004005dd <+141>:   ucomiss %xmm0,%xmm0         ; check for NaN on
real
   0x00000000004005e0 <+144>:   jnp    0x4005e7 <main+151>  ; if OK, continue
   0x00000000004005e2 <+146>:   ucomiss %xmm5,%xmm5         ; check for NaN on
imag
   0x00000000004005e5 <+149>:   jp     0x400602 <main+178>  ; recompute if bad
result
   0x00000000004005e7 <+151>:   cvtss2sd %xmm0,%xmm0
   0x00000000004005eb <+155>:   cvtss2sd %xmm5,%xmm1
   0x00000000004005ef <+159>:   mov    $0x400944,%edi
   0x00000000004005f4 <+164>:   mov    $0x2,%al
   0x00000000004005f6 <+166>:   callq  0x400430 <printf@plt>
   0x00000000004005fb <+171>:   xor    %eax,%eax
   0x00000000004005fd <+173>:   add    $0x18,%rsp
   0x0000000000400601 <+177>:   retq
   0x0000000000400602 <+178>:   movaps %xmm7,%xmm0
   0x0000000000400605 <+181>:   callq  0x400620 <__mulsc3>
   0x000000000040060a <+186>:   movaps %xmm0,%xmm5
   0x000000000040060d <+189>:   shufps $0xe5,%xmm5,%xmm5
   0x0000000000400611 <+193>:   jmp    0x4005e7 <main+151>