[Bug target/120351] ldrex r1, [s14], invalid use of NEON registers

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120351

--- Comment #2 from Sam James <sjames at gcc dot gnu.org> ---
```
# diff -u <(g++-14 /tmp/a.cxx -O2 -S -mfpu=neon -o -) <(g++-15 /tmp/a.cxx -O2
-S -mfpu=neon -o -)
--- /dev/fd/63  2025-05-19 10:57:07.663372453 -0000
+++ /dev/fd/62  2025-05-19 10:57:07.666705782 -0000
@@ -31,10 +31,9 @@
        .pad #32
        sub     sp, sp, #32
        ldr     r3, .L7+4
-       add     r4, sp, #20
+       add     r0, sp, #20
 .LPIC0:
        add     r2, pc, r2
-       mov     r0, r4
        ldr     r3, [r2, r3]
        ldr     r3, [r3]
        str     r3, [sp, #28]
@@ -43,16 +42,15 @@
        mov     r0, sp
        bl      _ZN1BC1Ev(PLT)
        vldr    d7, [sp]
-       vmov    r3, s14 @ int
        vstr    d7, [sp, #8]
 .L3:
-       ldrex   r1, [r3]
+       ldrex   r1, [s14]
        add     r1, r1, #1
-       strex   r2, r1, [r3]
+       strex   r2, r1, [s14]
        cmp     r2, #0
        bne     .L3
        add     r1, sp, #8
-       mov     r0, r4
+       add     r0, sp, #20
        bl      _ZN1B9insertOneES_(PLT)
        ldr     r2, .L7+8
        ldr     r3, .L7+4
```