On Thu, 14 May 2020 at 17:07, Ramana Radhakrishnan
<ramana....@googlemail.com> wrote:
>
> On Thu, May 14, 2020 at 3:58 PM Christophe Lyon via Gcc-patches
> <gcc-patches@gcc.gnu.org> wrote:
> >
> > The same code pattern occurs in several functions, so it seems cleaner
> > to move it into a dedicated function.
> >
> > 2020-05-14 Christophe Lyon <christophe.l...@linaro.org>
> >
> > gcc/
> > * config/arm/arm.c (reg_needs_saving_p): New function.
> > (use_return_insn): Use reg_needs_saving_p.
> > (arm_get_vfp_saved_size): Likewise.
> > (arm_compute_frame_layout): Likewise.
> > (arm_save_coproc_regs): Likewise.
> > (thumb1_expand_epilogue): Likewise.
> > (arm_expand_epilogue_apcs_frame): Likewise.
> > (arm_expand_epilogue): Likewise.
> > ---
> > gcc/config/arm/arm.c | 46 ++++++++++++++++++++++++----------------------
> > 1 file changed, 24 insertions(+), 22 deletions(-)
> >
> > diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
> > index c88de3e..694c1bb 100644
> > --- a/gcc/config/arm/arm.c
> > +++ b/gcc/config/arm/arm.c
> > @@ -4188,6 +4188,18 @@ arm_trampoline_adjust_address (rtx addr)
> > return addr;
> > }
> >
> > +/* Return 1 if REG needs to be saved. */
> > +static bool reg_needs_saving_p (unsigned reg)
>
> static inline ?
>
OK
> > +{
> > + unsigned long func_type = arm_current_func_type ();
>
> Why is this needed here when it's not used further ?
>
Ha, because I forgot to move this to
https://gcc.gnu.org/pipermail/gcc-patches/2020-May/545749.html
> > +
> > + if (!df_regs_ever_live_p (reg)
> > + || call_used_or_fixed_reg_p (reg))
> > + return false;
> > + else
> > + return true;
> > +}
> > +
> > /* Return 1 if it is possible to return using a single instruction.
> > If SIBLING is non-null, this is a test for a return before a sibling
> > call. SIBLING is the call insn, so we can examine its register usage.
> > */
> > @@ -4317,12 +4329,12 @@ use_return_insn (int iscond, rtx sibling)
> > since this also requires an insn. */
> > if (TARGET_VFP_BASE)
> > for (regno = FIRST_VFP_REGNUM; regno <= LAST_VFP_REGNUM; regno++)
> > - if (df_regs_ever_live_p (regno) && !call_used_or_fixed_reg_p (regno))
> > + if (reg_needs_saving_p (regno))
> > return 0;
> >
> > if (TARGET_REALLY_IWMMXT)
> > for (regno = FIRST_IWMMXT_REGNUM; regno <= LAST_IWMMXT_REGNUM; regno++)
> > - if (df_regs_ever_live_p (regno) && ! call_used_or_fixed_reg_p
> > (regno))
> > + if (reg_needs_saving_p (regno))
> > return 0;
> >
> > return 1;
> > @@ -20943,7 +20955,6 @@ thumb1_compute_save_core_reg_mask (void)
> > return mask;
> > }
> >
> > -
> > /* Return the number of bytes required to save VFP registers. */
> > static int
> > arm_get_vfp_saved_size (void)
> > @@ -20961,10 +20972,7 @@ arm_get_vfp_saved_size (void)
> > regno < LAST_VFP_REGNUM;
> > regno += 2)
> > {
> > - if ((!df_regs_ever_live_p (regno)
> > - || call_used_or_fixed_reg_p (regno))
> > - && (!df_regs_ever_live_p (regno + 1)
> > - || call_used_or_fixed_reg_p (regno + 1)))
> > + if (!reg_needs_saving_p (regno) && !reg_needs_saving_p (regno +
> > 1))
> > {
> > if (count > 0)
> > {
> > @@ -22489,8 +22497,7 @@ arm_compute_frame_layout (void)
> > for (regno = FIRST_IWMMXT_REGNUM;
> > regno <= LAST_IWMMXT_REGNUM;
> > regno++)
> > - if (df_regs_ever_live_p (regno)
> > - && !call_used_or_fixed_reg_p (regno))
> > + if (reg_needs_saving_p (regno))
> > saved += 8;
> > }
> >
> > @@ -22711,8 +22718,9 @@ arm_save_coproc_regs(void)
> > unsigned start_reg;
> > rtx insn;
> >
> > + if (TARGET_REALLY_IWMMXT)
> > for (reg = LAST_IWMMXT_REGNUM; reg >= FIRST_IWMMXT_REGNUM; reg--)
> > - if (df_regs_ever_live_p (reg) && !call_used_or_fixed_reg_p (reg))
> > + if (reg_needs_saving_p (reg))
> > {
> > insn = gen_rtx_PRE_DEC (Pmode, stack_pointer_rtx);
> > insn = gen_rtx_MEM (V2SImode, insn);
> > @@ -22727,9 +22735,7 @@ arm_save_coproc_regs(void)
> >
> > for (reg = FIRST_VFP_REGNUM; reg < LAST_VFP_REGNUM; reg += 2)
> > {
> > - if ((!df_regs_ever_live_p (reg) || call_used_or_fixed_reg_p (reg))
> > - && (!df_regs_ever_live_p (reg + 1)
> > - || call_used_or_fixed_reg_p (reg + 1)))
> > + if (!reg_needs_saving_p (reg) && !reg_needs_saving_p (reg + 1))
> > {
> > if (start_reg != reg)
> > saved_size += vfp_emit_fstmd (start_reg,
> > @@ -27024,7 +27030,7 @@ thumb1_expand_epilogue (void)
> > /* Emit a clobber for each insn that will be restored in the epilogue,
> > so that flow2 will get register lifetimes correct. */
> > for (regno = 0; regno < 13; regno++)
> > - if (df_regs_ever_live_p (regno) && !call_used_or_fixed_reg_p (regno))
> > + if (reg_needs_saving_p (regno))
> > emit_clobber (gen_rtx_REG (SImode, regno));
> >
> > if (! df_regs_ever_live_p (LR_REGNUM))
> > @@ -27090,9 +27096,7 @@ arm_expand_epilogue_apcs_frame (bool really_return)
> >
> > for (i = FIRST_VFP_REGNUM; i < LAST_VFP_REGNUM; i += 2)
> > /* Look for a case where a reg does not need restoring. */
> > - if ((!df_regs_ever_live_p (i) || call_used_or_fixed_reg_p (i))
> > - && (!df_regs_ever_live_p (i + 1)
> > - || call_used_or_fixed_reg_p (i + 1)))
> > + if (!reg_needs_saving_p (i) && !reg_needs_saving_p (i + 1))
> > {
> > if (start_reg != i)
> > arm_emit_vfp_multi_reg_pop (start_reg,
> > @@ -27119,7 +27123,7 @@ arm_expand_epilogue_apcs_frame (bool really_return)
> > int lrm_count = (num_regs % 2) ? (num_regs + 2) : (num_regs + 1);
> >
> > for (i = LAST_IWMMXT_REGNUM; i >= FIRST_IWMMXT_REGNUM; i--)
> > - if (df_regs_ever_live_p (i) && !call_used_or_fixed_reg_p (i))
> > + if (reg_needs_saving_p (i))
> > {
> > rtx addr = gen_frame_mem (V2SImode,
> > plus_constant (Pmode,
> > hard_frame_pointer_rtx,
> > @@ -27324,9 +27328,7 @@ arm_expand_epilogue (bool really_return)
> > unlike pop, vldm can only do consecutive regs. */
> > for (i = LAST_VFP_REGNUM - 1; i >= FIRST_VFP_REGNUM; i -= 2)
> > /* Look for a case where a reg does not need restoring. */
> > - if ((!df_regs_ever_live_p (i) || call_used_or_fixed_reg_p (i))
> > - && (!df_regs_ever_live_p (i + 1)
> > - || call_used_or_fixed_reg_p (i + 1)))
> > + if (!reg_needs_saving_p (i) && !reg_needs_saving_p (i + 1))
> > {
> > /* Restore the regs discovered so far (from reg+2 to
> > end_reg). */
> > @@ -27348,7 +27350,7 @@ arm_expand_epilogue (bool really_return)
> >
> > if (TARGET_IWMMXT)
> > for (i = FIRST_IWMMXT_REGNUM; i <= LAST_IWMMXT_REGNUM; i++)
> > - if (df_regs_ever_live_p (i) && !call_used_or_fixed_reg_p (i))
> > + if (reg_needs_saving_p (i))
> > {
> > rtx_insn *insn;
> > rtx addr = gen_rtx_MEM (V2SImode,
> > --
> > 2.7.4
> >
>
> OK with those changes.
>
Thanks
> Ramana
