[Bug target/84377] gcc-7.3.0 miscompiles truncf128@@GLIBC_2.26 in libm.so

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84377

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
GCC 7.3.0:
```
        .loc 1 42 0 discriminator 2
        movl    $65535, %edi
        movl    $-1, %esi
        movl    $0, 48(%esp)
        shrdl   %edi, %esi
        testb   $32, %cl
        sarx    %ecx, %edi, %edi
        movl    $0, 52(%esp)
        cmovne  %edi, %esi
        andn    %eax, %esi, %esi
        andn    %edx, %esi, %edi
        movl    %esi, 56(%esp)
        movl    %edi, 60(%esp)
        vmovdqa 48(%esp), %xmm3
        vmovaps %xmm3, (%esp)
```

GCC 7.4.0:
```
        .loc 1 42 0 discriminator 2
        movl    $65535, %edi
        movl    $-1, %esi
        movl    $0, 48(%esp)
        shrdl   %edi, %esi
        sarx    %ecx, %edi, %edi
        movl    %edi, %ebx
        movl    $0, 52(%esp)
        sarl    $31, %ebx
        testb   $32, %cl
        cmovne  %edi, %esi
        cmovne  %ebx, %edi
        andn    %eax, %esi, %esi
        andn    %edx, %edi, %edi
        movl    %esi, 56(%esp)
        movl    %edi, 60(%esp)
        vmovdqa 48(%esp), %xmm3
        vmovaps %xmm3, (%esp)
```