[PATCH/IPA] Fix ipa-polymorphic-call when size of Pmode is not the size of pointers in user code

[Jan Hubicka]

> Hi,
>   For ILP32 on AARCH64, we have ptr_mode != Pmode (we have ptr_mode
> being SImode while Pmode is DImode and POINTER_SIZE is 32).  This
> breaks ipa-polymorphic-call assumption that Pmode is the correct mode
> for pointers.  Right now before this patch we get many testcase
> failures in the C++ testsuite due to this.  Some of the tests fail due
> to the wrong devirtualization happening (using the base class rather
> the current class).
> 
> This patch fixes the issue by using POINTER_SIZE in place of
> GET_MODE_BITSIZE (Pmode) all over the file.
> 
> OK?  Bootstrapped and tested on x86_64 and cross built and tested for
> aarch64-elf with no regressions.
> 
> Thanks,
> Andrew Pinski
> 
> ChangeLog:
> ipa/63981
> * ipa-polymorphic-call.c (possible_placement_new):
> Use POINTER_SIZE instead of GET_MODE_BITSIZE (Pmode).
> (ipa_polymorphic_call_context::restrict_to_inner_class): Likewise.
> (extr_type_from_vtbl_ptr_store): Likewise.

OK,
thanks!
Honza

> diff --git a/gcc/ipa-polymorphic-call.c b/gcc/ipa-polymorphic-call.c
> index 452f2d2..a746c49 100644
> --- a/gcc/ipa-polymorphic-call.c
> +++ b/gcc/ipa-polymorphic-call.c
> @@ -112,7 +112,7 @@ possible_placement_new (tree type, tree expected_type,
>  	      || !tree_fits_shwi_p (TYPE_SIZE (type))
>  	      || (cur_offset
>  		  + (expected_type ? tree_to_uhwi (TYPE_SIZE (expected_type))
> -		     : GET_MODE_BITSIZE (Pmode))
> +		     : POINTER_SIZE)
>  		  <= tree_to_uhwi (TYPE_SIZE (type)))));
>  }
>  
> @@ -155,7 +155,7 @@ ipa_polymorphic_call_context::restrict_to_inner_class (tree otr_type,
>    HOST_WIDE_INT cur_offset = offset;
>    bool speculative = false;
>    bool size_unknown = false;
> -  unsigned HOST_WIDE_INT otr_type_size = GET_MODE_BITSIZE (Pmode);
> +  unsigned HOST_WIDE_INT otr_type_size = POINTER_SIZE;
>  
>    /* Update OUTER_TYPE to match EXPECTED_TYPE if it is not set.  */
>    if (!outer_type)
> @@ -316,7 +316,7 @@ ipa_polymorphic_call_context::restrict_to_inner_class (tree otr_type,
>  		
>  	      if (pos <= (unsigned HOST_WIDE_INT)cur_offset
>  		  && (pos + size) >= (unsigned HOST_WIDE_INT)cur_offset
> -				     + GET_MODE_BITSIZE (Pmode)
> +				     + POINTER_SIZE
>  		  && (!otr_type
>  		      || !TYPE_SIZE (TREE_TYPE (fld))
>  		      || !tree_fits_shwi_p (TYPE_SIZE (TREE_TYPE (fld)))
> @@ -1243,7 +1243,7 @@ extr_type_from_vtbl_ptr_store (gimple stmt, struct type_change_info *tci,
>  	      print_generic_expr (dump_file, tci->instance, TDF_SLIM);
>  	      fprintf (dump_file, " with offset %i\n", (int)tci->offset);
>  	    }
> -	  return tci->offset > GET_MODE_BITSIZE (Pmode) ? error_mark_node : NULL_TREE;
> +	  return tci->offset > POINTER_SIZE ? error_mark_node : NULL_TREE;
>  	}
>        if (offset != tci->offset
>  	  || size != POINTER_SIZE
> @@ -1252,9 +1252,9 @@ extr_type_from_vtbl_ptr_store (gimple stmt, struct type_change_info *tci,
>  	  if (dump_file)
>  	    fprintf (dump_file, "    wrong offset %i!=%i or size %i\n",
>  		     (int)offset, (int)tci->offset, (int)size);
> -	  return offset + GET_MODE_BITSIZE (Pmode) <= tci->offset
> +	  return offset + POINTER_SIZE <= tci->offset
>  	         || (max_size != -1
> -		     && tci->offset + GET_MODE_BITSIZE (Pmode) > offset + max_size)
> +		     && tci->offset + POINTER_SIZE > offset + max_size)
>  		 ? error_mark_node : NULL;
>  	}
>      }