On Wed, 2026-10-21 at 20:35 +0530, Surya Kumari Jangala wrote:
>
>
> On 12/10/26 3:35 PM, Avinash Jayakar wrote:
> > Hi,
> >
> > Addressed the comments in
> > https://gcc.gnu.org/pipermail/gcc-patches/2026-October/733494.html
> >
> > Changes from v1:
> > - Correct commit message.
> > - Update the max value of the type size properly.
> > - Update type of mode_to_unit_size fn, which uses the updated
> > array.
>
> Not just the uses of mode_unit_size[], but all the uses of
> GET_MODE_UNIT_SIZE too need to be
> checked to confirm that correct type is used. Please check the code,
> if not already done.
>
> - Surya
I verified all the uses of GET_MODE_UNIT_SIZE. All places use unsigned
int or just int.
Thanks,
Avinash
>
>
> >
> > Bootstrapped and regtested on {x86_64,powerpc64le}-linux-gnu. Ok
> > for
> > trunk?
> >
> > Thanks,
> > Avinash
> >
> > The mode_unit_size array that is generated from
> > emit_mode_unit_size_inline function currently hard codes the type
> > of
> > this array to unsigned char, since for most architectures the
> > mode_unit_size never exceeded 255.
> >
> > For rs6000 however, we add an opaque mode with 256 bytes which
> > overflows
> > this type. Therefore this patch adds a macro named
> > MODE_UNIT_SIZE_TYPE
> > in the generated file which is defined based on the maximum value
> > that
> > the mode_unit_size array will hold.
> > if < 256, unsigned char
> > else if < 2^16, unsigned short
> > else, unsigned int
> >
> > 2026-10-12 Avinash Jayakar <[email protected]>
> >
> > gcc/ChangeLog:
> > * genmodes.cc (emit_mode_unit_size): Generate
> > MODE_UNIT_SIZE_TYPE
> > macro based on values in mode_unit_size.
> > * machmode.h: Use the new macro.
> > ---
> > gcc/genmodes.cc | 21 ++++++++++++++++++---
> > gcc/machmode.h | 4 ++--
> > 2 files changed, 20 insertions(+), 5 deletions(-)
> >
> > diff --git a/gcc/genmodes.cc b/gcc/genmodes.cc
> > index fa5f8923519..ed8bfd3ba3a 100644
> > --- a/gcc/genmodes.cc
> > +++ b/gcc/genmodes.cc
> > @@ -1167,16 +1167,31 @@ emit_mode_unit_size_inline (void)
> > int c;
> > struct mode_data *m;
> >
> > + unsigned int max_type_size = 0;
> > + for_all_modes (c, m)
> > + {
> > + unsigned int type_size = (c != MODE_PARTIAL_INT && m-
> > >component)
> > + ? m->component->bytesize : m-
> > >bytesize;
> > + if (max_type_size < type_size)
> > + max_type_size = type_size;
> > + }
> > + if (max_type_size < (1 << 8))
> > + puts ("#define MODE_UNIT_SIZE_TYPE unsigned char\n");
> > + else if (max_type_size < (1 << 16))
> > + puts ("#define MODE_UNIT_SIZE_TYPE unsigned short\n");
> > + else
> > + puts ("#define MODE_UNIT_SIZE_TYPE unsigned int\n");
> > +
> > puts ("\
> > #ifdef __cplusplus\n\
> > inline __attribute__((__always_inline__))\n\
> > #else\n\
> > extern __inline__ __attribute__((__always_inline__,
> > __gnu_inline__))\n\
> > #endif\n\
> > -unsigned char\n\
> > +MODE_UNIT_SIZE_TYPE\n\
> > mode_unit_size_inline (machine_mode mode)\n\
> > {\n\
> > - extern CONST_MODE_UNIT_SIZE unsigned char
> > mode_unit_size[NUM_MACHINE_MODES];\
> > + extern CONST_MODE_UNIT_SIZE MODE_UNIT_SIZE_TYPE
> > mode_unit_size[NUM_MACHINE_MODES];\
> > \n\
> > gcc_assert (mode >= 0 && mode < NUM_MACHINE_MODES);\n\
> > switch (mode)\n\
> > @@ -1683,7 +1698,7 @@ emit_mode_unit_size (void)
> > int c;
> > struct mode_data *m;
> >
> > - print_maybe_const_decl ("%sunsigned char", "mode_unit_size",
> > + print_maybe_const_decl ("%sMODE_UNIT_SIZE_TYPE",
> > "mode_unit_size",
> > "NUM_MACHINE_MODES", adj_bytesize);
> >
> > for_all_modes (c, m)
> > diff --git a/gcc/machmode.h b/gcc/machmode.h
> > index bc564d6bc13..fa439714bcb 100644
> > --- a/gcc/machmode.h
> > +++ b/gcc/machmode.h
> > @@ -26,7 +26,7 @@ extern CONST_MODE_SIZE poly_uint16
> > mode_size[NUM_MACHINE_MODES];
> > extern CONST_MODE_PRECISION poly_uint16
> > mode_precision[NUM_MACHINE_MODES];
> > extern const unsigned short mode_inner[NUM_MACHINE_MODES];
> > extern CONST_MODE_NUNITS poly_uint16
> > mode_nunits[NUM_MACHINE_MODES];
> > -extern CONST_MODE_UNIT_SIZE unsigned char
> > mode_unit_size[NUM_MACHINE_MODES];
> > +extern CONST_MODE_UNIT_SIZE MODE_UNIT_SIZE_TYPE
> > mode_unit_size[NUM_MACHINE_MODES];
> > extern const unsigned short
> > mode_unit_precision[NUM_MACHINE_MODES];
> > extern const unsigned short mode_next[NUM_MACHINE_MODES];
> > extern const unsigned short mode_wider[NUM_MACHINE_MODES];
> > @@ -611,7 +611,7 @@ mode_to_inner (machine_mode mode)
> >
> > /* Return the base GET_MODE_UNIT_SIZE value for MODE. */
> >
> > -ALWAYS_INLINE unsigned char
> > +ALWAYS_INLINE MODE_UNIT_SIZE_TYPE
> > mode_to_unit_size (machine_mode mode)
> > {
> > #if GCC_VERSION >= 4001
