Tom de Vries <tom_devr...@mentor.com> writes:
> +/* Collect hard register usage for the current function. */
> +
> +static void
> +collect_fn_hard_reg_usage (void)
> +{
> + rtx insn;
> + int i;
> + struct cgraph_node *node;
> +
> + if (!flag_use_caller_save)
> + return;
> +
> + node = cgraph_get_node (current_function_decl);
> + gcc_assert (node != NULL);
> +
> + gcc_assert (!node->function_used_regs_initialized);
> + node->function_used_regs_initialized = 1;
> +
> + for (insn = get_insns (); insn != NULL_RTX; insn = next_insn (insn))
> + {
> + HARD_REG_SET insn_used_regs;
> +
> + if (!NONDEBUG_INSN_P (insn))
> + continue;
> +
> + find_all_hard_reg_sets (insn, &insn_used_regs, false);
> +
> + if (CALL_P (insn)
> + && (!targetm.call_fusage_contains_non_callee_clobbers ()
> + || !get_call_reg_set_usage (insn, &insn_used_regs,
> call_used_reg_set)))
If the uses of flag_use_caller_save also check
call_fusage_contains_non_callee_clobbers, would it be better to test
them both together here too, rather than waiting to see a call?
> + /* Be conservative - mark fixed and global registers as used. */
> + IOR_HARD_REG_SET (node->function_used_regs, fixed_reg_set);
> + for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
> + if (global_regs[i])
> + SET_HARD_REG_BIT (node->function_used_regs, i);
The loop isn't needed; all globals are fixed.
Thanks again for working on this.
Richard
