Hi, Richi. >> I think you need to use fma from math.h together with -ffast-math >>to get fma. As you said, this is one of the case I tried: https://godbolt.org/z/xMzrrv5dT GCC failed to vectorize. Could you help me with this? Thanks. juzhe.zhong@rivai.ai From: Richard Biener Date: 2023-07-31 20:00 To: juzhe.zhong@rivai.ai CC: richard.sandiford; gcc-patches Subject: Re: Re: [PATCH V2] VECT: Support CALL vectorization for COND_LEN_* On Mon, 31 Jul 2023, juzhe.zhong@rivai.ai wrote: > Ok . Thanks Richard. > > Could you give me a case that SVE can vectorize a reduction with FMA? > Meaning it will go into vectorize_call and vectorize FMA into COND_FMA ? > > I tried many times to reproduce such cases but I failed. I think you need to use fma from math.h together with -ffast-math to get fma. Richard. > Thanks. > > > juzhe.zhong@rivai.ai > > From: Richard Sandiford > Date: 2023-07-31 18:19 > To: Juzhe-Zhong > CC: gcc-patches; rguenther > Subject: Re: [PATCH V2] VECT: Support CALL vectorization for COND_LEN_* > Juzhe-Zhong writes: > > Hi, Richard and Richi. > > > > Base on the suggestions from Richard: > > https://gcc.gnu.org/pipermail/gcc-patches/2023-July/625396.html > > > > This patch choose (1) approach that Richard provided, meaning: > > > > RVV implements cond_* optabs as expanders. RVV therefore supports > > both IFN_COND_ADD and IFN_COND_LEN_ADD. No dummy length arguments > > are needed at the gimple level. > > > > Such approach can make codes much cleaner and reasonable. > > > > Consider this following case: > > void foo (float * __restrict a, float * __restrict b, int * __restrict cond, int n) > > { > > for (int i = 0; i < n; i++) > > if (cond[i]) > > a[i] = b[i] + a[i]; > > } > > > > > > Output of RISC-V (32-bits) gcc (trunk) (Compiler #3) > > :5:21: missed: couldn't vectorize loop > > :5:21: missed: not vectorized: control flow in loop. > > > > ARM SVE: > > > > ... > > mask__27.10_51 = vect__4.9_49 != { 0, ... }; > > ... > > vec_mask_and_55 = loop_mask_49 & mask__27.10_51; > > ... > > vect__9.17_62 = .COND_ADD (vec_mask_and_55, vect__6.13_56, vect__8.16_60, vect__6.13_56); > > > > For RVV, we want IR as follows: > > > > ... > > _68 = .SELECT_VL (ivtmp_66, POLY_INT_CST [4, 4]); > > ... > > mask__27.10_51 = vect__4.9_49 != { 0, ... }; > > ... > > vect__9.17_60 = .COND_LEN_ADD (mask__27.10_51, vect__6.13_55, vect__8.16_59, vect__6.13_55, _68, 0); > > ... > > > > Both len and mask of COND_LEN_ADD are real not dummy. > > > > This patch has been fully tested in RISC-V port with supporting both COND_* and COND_LEN_*. > > > > And also, Bootstrap and Regression on X86 passed. > > > > OK for trunk? > > > > gcc/ChangeLog: > > > > * internal-fn.cc (FOR_EACH_LEN_FN_PAIR): New macro. > > (get_len_internal_fn): New function. > > (CASE): Ditto. > > * internal-fn.h (get_len_internal_fn): Ditto. > > * tree-vect-stmts.cc (vectorizable_call): Support CALL vectorization with COND_LEN_*. > > > > --- > > gcc/internal-fn.cc | 46 ++++++++++++++++++++++ > > gcc/internal-fn.h | 1 + > > gcc/tree-vect-stmts.cc | 87 +++++++++++++++++++++++++++++++++++++----- > > 3 files changed, 125 insertions(+), 9 deletions(-) > > > > diff --git a/gcc/internal-fn.cc b/gcc/internal-fn.cc > > index 8e294286388..379220bebc7 100644 > > --- a/gcc/internal-fn.cc > > +++ b/gcc/internal-fn.cc > > @@ -4443,6 +4443,52 @@ get_conditional_internal_fn (internal_fn fn) > > } > > } > > > > +/* Invoke T(IFN) for each internal function IFN that also has an > > + IFN_COND_LEN_* or IFN_MASK_LEN_* form. */ > > +#define FOR_EACH_LEN_FN_PAIR(T) \ > > + T (MASK_LOAD, MASK_LEN_LOAD) \ > > + T (MASK_STORE, MASK_LEN_STORE) \ > > + T (MASK_GATHER_LOAD, MASK_LEN_GATHER_LOAD) \ > > + T (MASK_SCATTER_STORE, MASK_LEN_SCATTER_STORE) \ > > + T (COND_ADD, COND_LEN_ADD) \ > > + T (COND_SUB, COND_LEN_SUB) \ > > + T (COND_MUL, COND_LEN_MUL) \ > > + T (COND_DIV, COND_LEN_DIV) \ > > + T (COND_MOD, COND_LEN_MOD) \ > > + T (COND_RDIV, COND_LEN_RDIV) \ > > + T (COND_FMIN, COND_LEN_FMIN) \ > > + T (COND_FMAX, COND_LEN_FMAX) \ > > + T (COND_MIN, COND_LEN_MIN) \ > > + T (COND_MAX, COND_LEN_MAX) \ > > + T (COND_AND, COND_LEN_AND) \ > > + T (COND_IOR, COND_LEN_IOR) \ > > + T (COND_XOR, COND_LEN_XOR) \ > > + T (COND_SHL, COND_LEN_SHL) \ > > + T (COND_SHR, COND_LEN_SHR) \ > > + T (COND_NEG, COND_LEN_NEG) \ > > + T (COND_FMA, COND_LEN_FMA) \ > > + T (COND_FMS, COND_LEN_FMS) \ > > + T (COND_FNMA, COND_LEN_FNMA) \ > > + T (COND_FNMS, COND_LEN_FNMS) > > With the earlier patch to add DEF_INTERNAL_COND_FN and > DEF_INTERNAL_SIGNED_COND_FN, I think we should use those to handle > the COND_* cases, rather than putting them in this macro. > > Thanks, > Richard > > -- Richard Biener SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg, Germany; GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)