On 03/01/2018 08:19 AM, Kyrill Tkachov wrote: > Ping. > > Thanks, > Kyrill > > On 19/02/18 11:35, Kyrill Tkachov wrote: >> Ping. >> >> https://gcc.gnu.org/ml/gcc-patches/2018-02/msg00649.html >> >> CC'ing Eric and Jeff as the patch contains a simplify-rtx.c component >> that I'll need midend approval on. >> >> Thanks everyone for your comments so far. >> Kyrill >> >> On 12/02/18 15:18, Kyrill Tkachov wrote: >>> Hi Richard, >>> >>> On 08/02/18 20:29, Richard Sandiford wrote: >>>> Thanks for doing this. >>>> >>>> Kyrill Tkachov <kyrylo.tkac...@foss.arm.com> writes: >>>>> diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c >>>>> index >>>>> 2e7aa5c12952ab1a9b49b5adaf23710327e577d3..af06d7502cebac03cefc689b2646874b8397e767 >>>>> 100644 >>>>> --- a/gcc/simplify-rtx.c >>>>> +++ b/gcc/simplify-rtx.c >>>>> @@ -6474,6 +6474,18 @@ simplify_subreg (machine_mode outermode, rtx >>>>> op, >>>>> return NULL_RTX; >>>>> } >>>>> + /* Simplify (subreg:QI (and:SI (reg:SI) (const_int 0xffff)) 0) >>>>> + into (subreg:QI (reg:SI) 0). */ >>>>> + scalar_int_mode int_outermode, int_innermode; >>>>> + if (!paradoxical_subreg_p (outermode, innermode) >>>>> + && is_a <scalar_int_mode> (outermode, &int_outermode) >>>>> + && is_a <scalar_int_mode> (innermode, &int_innermode) >>>>> + && GET_CODE (op) == AND && CONST_INT_P (XEXP (op, 1)) >>>>> + && known_eq (subreg_lowpart_offset (outermode, innermode), >>>>> byte) >>>>> + && (~INTVAL (XEXP (op, 1)) & GET_MODE_MASK (int_outermode)) >>>>> == 0 >>>>> + && validate_subreg (outermode, innermode, XEXP (op, 0), byte)) >>>>> + return gen_rtx_SUBREG (outermode, XEXP (op, 0), byte); >>>>> + >>>>> /* A SUBREG resulting from a zero extension may fold to zero if >>>>> it extracts higher bits that the ZERO_EXTEND's source bits. */ >>>>> if (GET_CODE (op) == ZERO_EXTEND && SCALAR_INT_MODE_P (innermode)) >>>> I think it'd be better to do this in simplify_truncation (shared >>>> by the subreg code and the TRUNCATE code). The return would then >>>> be simplify_gen_unary (TRUNCATE, ...), which will become a subreg >>>> if TRULY_NOOP_TRUNCATION. >>> >>> Thanks, that does look cleaner. >>> Bootstrapped and tested on arm-none-linux-gnueabihf, >>> aarch64-none-linux-gnu and x86_64-unknown-linux-gnu. >>> The other two patches are still needed to address the fallout. >>> >>> Is this ok? >>> >>> Thanks, >>> Kyrill >>> >>> 2018-02-12 Kyrylo Tkachov <kyrylo.tkac...@arm.com> >>> >>> PR target/84164 >>> * simplify-rtx.c (simplify_truncation): Simplify truncation of >>> masking >>> operation. >>> * config/aarch64/aarch64.md (*aarch64_reg_<mode>3_neg_mask2): >>> Use simplify_gen_unary creating a SUBREG. >>> (*aarch64_reg_<mode>3_minus_mask): Likewise. >>> (*aarch64_<optab>_reg_di3_mask2): Use const_int_operand predicate >>> for operand 3. >>> >>> 2018-02-12 Kyrylo Tkachov <kyrylo.tkac...@arm.com> >>> >>> PR target/84164 >>> * gcc.c-torture/compile/pr84164.c: New test. Sorry. I suspect I dropped this from my inbox when it had the AArch64 marker -- I didn't realize it had a target independent component.
The simplify-rtx bits are fine. The version in simplify_truncation is much better than the original in simplify_subreg (which I think needed to verify that you were looking at the lowpart before optimizing). jeff >> >
