[PATCH, GCC/ARM, 5/10] Clear VFP registers with VSCCLRM
This patch adds a new pattern for the VSCCLRM instruction.
cmse_clear_registers () is then modified to use the new VSCCLRM
instruction when targeting Armv8.1-M Mainline, thus, making the Armv8-M
register clearing code specific to Armv8-M.
Since the VSCCLRM instruction mandates VPR in the register list, the
pattern is encoded with a parallel which only requires an unspecified
VUNSPEC_CLRM_VPR constant modelling the APSR clearing. Other expression
in the parallel are expected to be set expression for clearing the VFP
registers.
*** gcc/ChangeLog ***
2020-01-16 Mihail-Calin Ionescu <mihail.ionescu@arm.com>
2020-01-16 Thomas Preud'homme <thomas.preudhomme@arm.com>
* config/arm/arm-protos.h (clear_operation_p): Adapt prototype.
* config/arm/arm.c (clear_operation_p): Extend to be able to check a
clear_vfp_multiple pattern based on a new vfp parameter.
(cmse_clear_registers): Generate VSCCLRM to clear VFP registers when
targeting Armv8.1-M Mainline.
(cmse_nonsecure_entry_clear_before_return): Clear VFP registers
unconditionally when targeting Armv8.1-M Mainline architecture. Check
whether VFP registers are available before looking call_used_regs for a
VFP register.
* config/arm/predicates.md (clear_multiple_operation): Adapt to change
of prototype of clear_operation_p.
(clear_vfp_multiple_operation): New predicate.
* config/arm/unspecs.md (VUNSPEC_VSCCLRM_VPR): New volatile unspec.
* config/arm/vfp.md (clear_vfp_multiple): New define_insn.
*** gcc/testsuite/ChangeLog ***
2020-01-16 Mihail-Calin Ionescu <mihail.ionescu@arm.com>
2020-01-16 Thomas Preud'homme <thomas.preudhomme@arm.com>
projects / thirdparty / gcc.git / commit
