[Ping][PATCH, ARM] PR71607: New approach to arm_disable_literal_pool

[Andre Vieira (lists)]

On 06/10/16 14:57, Andre Vieira (lists) wrote:
> Hello,
> 
> This patch tackles the issue reported in PR71607. This patch takes a
> different approach for disabling the creation of literal pools. Instead
> of disabling the patterns that would normally transform the rtl into
> actual literal pools, it disables the creation of this literal pool rtl
> by making the target hook TARGET_CANNOT_FORCE_CONST_MEM return true if
> arm_disable_literal_pool is true. I added patterns to split floating
> point constants for both SF and DFmode. A pattern to handle the
> addressing of label_refs had to be included as well since all
> "memory_operand" patterns are disabled when
> TARGET_CANNOT_FORCE_CONST_MEM returns true. Also the pattern for
> splitting 32-bit immediates had to be changed, it was not accepting
> unsigned 32-bit unsigned integers with the MSB set. I believe
> const_int_operand expects the mode of the operand to be set to VOIDmode
> and not SImode. I have only changed it in the patterns that were
> affecting this code, though I suggest looking into changing it in the
> rest of the ARM backend.
> 
> I added more test cases. No regressions for arm-none-eabi with
> Cortex-M0, Cortex-M3 and Cortex-M7.
> 
> Is this OK for trunk?
> 
> Cheers,
> Andre
> 
> gcc/ChangeLog:
> 
> 2016-10-06  Andre Vieira  <andre.simoesdiasvieira@arm.com>
> 
>     PR target/71607
>     * config/arm/arm.md (use_literal_pool): Remove.
>     (64-bit immediate split): No longer take cost into consideration
>     if 'arm_disable_literal_pool' is enabled.
>     (32-bit const split): Remove SImode from constant, which was
>     not allowing large unsigned integers to be split.
>     * config/arm/arm.c (thumb2_legitimate_address_p): Remove handling
>     of 'arm_disable_literal_pool' here.
>     (arm_max_const_double_inline_cost): Likewise.
>     (arm_cannot_force_const_mem): Return false for
> 'arm_disable_literal_pool'.
>     (thumb2_legitimate_address_p): Remove check involving
> 'arm_disable_literal_pool'
>     that is no longer relevant.
>     (arm_legitimate_constant_p): Ignore the outcome of
> 'arm_cannot_force_const_mem'
>     if 'arm_disable_literal_pool' is enabled.
>     * config/arm/vfp.md (no_literal_pool_df_immediate): New.
>     (no_literal_pool_sf_immediate): New.
>     * config/arm/thumb2.md (*thumb2_movsi_labelref_insn): New.
> 
> gcc/testsuite/ChangeLog:
> 
> 2016-10-06  Andre Vieira  <andre.simoesdiasvieira@arm.com>
>             Thomas Preud'homme  <thomas.preudhomme@arm.com>
> 
>     PR target/71607
>     * gcc.target/arm/thumb2-slow-flash-data.c: Rename to ...
>     * gcc.target/arm/thumb2-slow-flash-data-1.c: ... this.
>     * gcc.target/arm/thumb2-slow-flash-data-2.c: New.
>     * gcc.target/arm/thumb2-slow-flash-data-3.c: New.
> 
> 
Ping.