[Bug rtl-optimization/120329] Combine temporarily creates paradoxical mem subregs for strict-alignment targets

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120329

--- Comment #6 from Dimitar Dimitrov <dimitar at gcc dot gnu.org> ---
To reproduce after r16-718-geb2ea476db2182, apply the following change to
tighten paradoxical subreg checks, and build libgcc for
armv8l-unknown-linux-gnueabihf:

-  /* Do not allow normal SUBREG with stricter alignment than the inner MEM.
-
-     PR120329: Combine can create paradoxical mem subregs even for
-     strict-alignment targets.  Allow it until combine is fixed.  */
+  /* Do not allow SUBREG with stricter alignment than the inner MEM.  */
   else if (reg && MEM_P (reg) && STRICT_ALIGNMENT
-          && MEM_ALIGN (reg) < GET_MODE_ALIGNMENT (omode)
-          && known_le (osize, isize))
+          && MEM_ALIGN (reg) < GET_MODE_ALIGNMENT (omode))
     return false;