| Message ID | 87d15ew1gz.fsf@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [13/nn] More is_a <scalar_int_mode> | expand |
On Mon, Oct 23, 2017 at 1:25 PM, Richard Sandiford <richard.sandiford@linaro.org> wrote: > alias.c:find_base_term and find_base_value checked: > > if (GET_MODE_SIZE (GET_MODE (src)) < GET_MODE_SIZE (Pmode)) > > but (a) comparing the precision seems more correct, since it's possible > for modes to have the same memory size as Pmode but fewer bits and > (b) the functions are called on arbitrary rtl, so there's no guarantee > that we're handling an integer truncation. > > Since there's no point processing truncations of anything other than an > integer, this patch checks that first. Ok. Richard. > > 2017-10-23 Richard Sandiford <richard.sandiford@linaro.org> > Alan Hayward <alan.hayward@arm.com> > David Sherwood <david.sherwood@arm.com> > > gcc/ > * alias.c (find_base_value, find_base_term): Only process integer > truncations. Check the precision rather than the size. > > Index: gcc/alias.c > =================================================================== > --- gcc/alias.c 2017-10-23 11:41:25.511925516 +0100 > +++ gcc/alias.c 2017-10-23 11:44:27.544693078 +0100 > @@ -1349,6 +1349,7 @@ known_base_value_p (rtx x) > find_base_value (rtx src) > { > unsigned int regno; > + scalar_int_mode int_mode; > > #if defined (FIND_BASE_TERM) > /* Try machine-dependent ways to find the base term. */ > @@ -1475,7 +1476,8 @@ find_base_value (rtx src) > address modes depending on the address space. */ > if (!target_default_pointer_address_modes_p ()) > break; > - if (GET_MODE_SIZE (GET_MODE (src)) < GET_MODE_SIZE (Pmode)) > + if (!is_a <scalar_int_mode> (GET_MODE (src), &int_mode) > + || GET_MODE_PRECISION (int_mode) < GET_MODE_PRECISION (Pmode)) > break; > /* Fall through. */ > case HIGH: > @@ -1876,6 +1878,7 @@ find_base_term (rtx x) > cselib_val *val; > struct elt_loc_list *l, *f; > rtx ret; > + scalar_int_mode int_mode; > > #if defined (FIND_BASE_TERM) > /* Try machine-dependent ways to find the base term. */ > @@ -1893,7 +1896,8 @@ find_base_term (rtx x) > address modes depending on the address space. */ > if (!target_default_pointer_address_modes_p ()) > return 0; > - if (GET_MODE_SIZE (GET_MODE (x)) < GET_MODE_SIZE (Pmode)) > + if (!is_a <scalar_int_mode> (GET_MODE (x), &int_mode) > + || GET_MODE_PRECISION (int_mode) < GET_MODE_PRECISION (Pmode)) > return 0; > /* Fall through. */ > case HIGH:
Index: gcc/alias.c =================================================================== --- gcc/alias.c 2017-10-23 11:41:25.511925516 +0100 +++ gcc/alias.c 2017-10-23 11:44:27.544693078 +0100 @@ -1349,6 +1349,7 @@ known_base_value_p (rtx x) find_base_value (rtx src) { unsigned int regno; + scalar_int_mode int_mode; #if defined (FIND_BASE_TERM) /* Try machine-dependent ways to find the base term. */ @@ -1475,7 +1476,8 @@ find_base_value (rtx src) address modes depending on the address space. */ if (!target_default_pointer_address_modes_p ()) break; - if (GET_MODE_SIZE (GET_MODE (src)) < GET_MODE_SIZE (Pmode)) + if (!is_a <scalar_int_mode> (GET_MODE (src), &int_mode) + || GET_MODE_PRECISION (int_mode) < GET_MODE_PRECISION (Pmode)) break; /* Fall through. */ case HIGH: @@ -1876,6 +1878,7 @@ find_base_term (rtx x) cselib_val *val; struct elt_loc_list *l, *f; rtx ret; + scalar_int_mode int_mode; #if defined (FIND_BASE_TERM) /* Try machine-dependent ways to find the base term. */ @@ -1893,7 +1896,8 @@ find_base_term (rtx x) address modes depending on the address space. */ if (!target_default_pointer_address_modes_p ()) return 0; - if (GET_MODE_SIZE (GET_MODE (x)) < GET_MODE_SIZE (Pmode)) + if (!is_a <scalar_int_mode> (GET_MODE (x), &int_mode) + || GET_MODE_PRECISION (int_mode) < GET_MODE_PRECISION (Pmode)) return 0; /* Fall through. */ case HIGH:
alias.c:find_base_term and find_base_value checked: if (GET_MODE_SIZE (GET_MODE (src)) < GET_MODE_SIZE (Pmode)) but (a) comparing the precision seems more correct, since it's possible for modes to have the same memory size as Pmode but fewer bits and (b) the functions are called on arbitrary rtl, so there's no guarantee that we're handling an integer truncation. Since there's no point processing truncations of anything other than an integer, this patch checks that first. 2017-10-23 Richard Sandiford <richard.sandiford@linaro.org> Alan Hayward <alan.hayward@arm.com> David Sherwood <david.sherwood@arm.com> gcc/ * alias.c (find_base_value, find_base_term): Only process integer truncations. Check the precision rather than the size.