Hi Juzhe, I meant that “lens” is undefined, from looking around I guess that needs to be vec_loop_lens *lens = &LOOP_VINFO_LENS (loop_vinfo); for `bias` I meant cond = gimple_build (&cond_gsi, IFN_VCOND_MASK_LEN, truth_type, all true mask, cond, all false mask, len, bias); that variable `bias` isn’t defined. And I can’t find any other usage of IFN_VCOND_MASK_LEN creation to figure out what it’s supposed to be 😊 is it just an SImode 0? Thanks, Tamar From: juzhe.zhong@rivai.ai Sent: Thursday, November 30, 2023 11:49 AM To: Tamar Christina ; gcc-patches Cc: Richard Biener Subject: Re: RE: [PATCH 9/21]middle-end: implement vectorizable_early_exit for codegen of exit code Thanks Tamar. I am not sure whether I am not on the same page with you. IMHO, ARM SVE will use the final mask = loop mask (generate by WHILE_ULT) & conditional mask. Use that final mask to do the cbranch. Am I right ? If yes, I leverage that for length and avoid too much codes change in your patch. So, for RVV, the length is pretty same as loop mask in ARM SVE. For example, suppose n = 4, in ARM SVE, WHILE_ULT (whilelo) generate mask = 0b11110000000.... Then use that mask to control the operations. For RVV, is the same, length will be 4, then we will only process the elements with index < 4. For bias, I think that won't be the issue. Currently, BIAS is not used by RVV and only used on len_load/len_store for IBM targets. So, the bias value by default is 0 in all other situations except len_load/len_store specifically for IBM. ________________________________ juzhe.zhong@rivai.ai From: Tamar Christina Date: 2023-11-30 18:39 To: juzhe.zhong@rivai.ai; gcc-patches CC: Richard Biener Subject: RE: [PATCH 9/21]middle-end: implement vectorizable_early_exit for codegen of exit code Hi Juzhe, I’m happy to take the hunks, just that I can’t test it and don’t know the specifics of how it lens work. I still need to read up on it. I tried adding that chunk in, but for the first bit `lens` seems undefined, and the second bit it seems `bias` is undefined. I’ll also need what to do for vectorizable_live_operations how to get the first element rather than the last. Thanks, Tamar From: juzhe.zhong@rivai.ai > Sent: Thursday, November 30, 2023 4:48 AM To: gcc-patches > Cc: Richard Biener >; Tamar Christina > Subject: [PATCH 9/21]middle-end: implement vectorizable_early_exit for codegen of exit code Hi, Richard and Tamar. I am sorry for bothering you. Hope you don't mind I give some comments: Can we support partial vector for length ? IMHO, we can do that as follows: bool length_loop_p = LOOP_VINFO_FULLY_WITH_LENGTH_P (loop_vinfo); if (LOOP_VINFO_CAN_USE_PARTIAL_VECTORS_P (loop_vinfo)) { if (direct_internal_fn_supported_p (IFN_VCOND_MASK_LEN, vectype, OPTIMIZE_FOR_SPEED)) vect_record_loop_len (loop_vinfo, lens, ncopies, vectype, 1); else vect_record_loop_mask (loop_vinfo, masks, ncopies, truth_type, NULL); } if (length_loop_p) { tree len = vect_get_loop_len (loop_vinfo, gsi, loop_lens, 1, vectype, 0, 0); /* Use VCOND_MASK_LEN (all true, cond, all false, len, bias) to generate final mask = i < len + bias ? cond[i] : false. */ cond = gimple_build (&cond_gsi, IFN_VCOND_MASK_LEN, truth_type, all true mask, cond, all false mask, len, bias); } else if (masked_loop_p) { tree mask = vect_get_loop_mask (loop_vinfo, gsi, masks, ncopies, truth_type, 0); cond = prepare_vec_mask (loop_vinfo, TREE_TYPE (mask), mask, cond, &cond_gsi); } This is a prototype. Is this idea reasonable to Richi ? Thanks. ________________________________ juzhe.zhong@rivai.ai