Re: [PATCH v2 2/6] arm: Fix the "c" constraint
On 11/14/19 2:07 PM, Kyrill Tkachov wrote: > > On 11/14/19 10:07 AM, Richard Henderson wrote: >> The existing definition using register class CC_REG does not >> work because CC_REGNUM does not support normal modes, and so >> fails to match register_operand. Use a non-register constraint >> and the cc_register predicate instead. >> >> * config/arm/constraints.md (c): Use cc_register predicate. > > > Ok. > > Does this need a backport to the branches? I don't think so, because it is currently unused. I tried to track down if it was *ever* used and did not succeed. The first reference I see is commit cffb2a26c44c682185b6bb405d48fcbe1fbc0b37 Author: rearnsha Date: Sat Apr 8 14:29:53 2000 + Merge changes from merged-arm-thumb-backend-branch onto trunk. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@33028 \ 138bc75d-0d04-0410-961f-82ee72b054a4 within REG_CLASS_FROM_LETTER. But I cannot find a user of the constraint within a checkout of that revision. Unless I miss something, it seems to have been garbage for a very long time. r~
Re: [PATCH v2 2/6] arm: Fix the "c" constraint
On 11/14/19 10:07 AM, Richard Henderson wrote: The existing definition using register class CC_REG does not work because CC_REGNUM does not support normal modes, and so fails to match register_operand. Use a non-register constraint and the cc_register predicate instead. * config/arm/constraints.md (c): Use cc_register predicate. Ok. Does this need a backport to the branches? Thanks, Kyrill --- gcc/config/arm/constraints.md | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/gcc/config/arm/constraints.md b/gcc/config/arm/constraints.md index b76de81b85c..e02b678d26d 100644 --- a/gcc/config/arm/constraints.md +++ b/gcc/config/arm/constraints.md @@ -94,8 +94,9 @@ "@internal Thumb only. The union of the low registers and the stack register.") -(define_register_constraint "c" "CC_REG" - "@internal The condition code register.") +(define_constraint "c" + "@internal The condition code register." + (match_operand 0 "cc_register")) (define_register_constraint "Cs" "CALLER_SAVE_REGS" "@internal The caller save registers. Useful for sibcalls.") -- 2.17.1
[PATCH v2 2/6] arm: Fix the "c" constraint
The existing definition using register class CC_REG does not work because CC_REGNUM does not support normal modes, and so fails to match register_operand. Use a non-register constraint and the cc_register predicate instead. * config/arm/constraints.md (c): Use cc_register predicate. --- gcc/config/arm/constraints.md | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/gcc/config/arm/constraints.md b/gcc/config/arm/constraints.md index b76de81b85c..e02b678d26d 100644 --- a/gcc/config/arm/constraints.md +++ b/gcc/config/arm/constraints.md @@ -94,8 +94,9 @@ "@internal Thumb only. The union of the low registers and the stack register.") -(define_register_constraint "c" "CC_REG" - "@internal The condition code register.") +(define_constraint "c" + "@internal The condition code register." + (match_operand 0 "cc_register")) (define_register_constraint "Cs" "CALLER_SAVE_REGS" "@internal The caller save registers. Useful for sibcalls.") -- 2.17.1
