From f574e2dfae79055f16d0c63cc12df24815d8ead6 Mon Sep 17 00:00:00 2001 From: Ju-Zhe Zhong Date: Thu, 25 May 2023 22:42:35 +0800 Subject: VECT: Add decrement IV iteration loop control by variable amount support This patch is supporting decrement IV by following the flow designed by Richard: (1) In vect_set_loop_condition_partial_vectors, for the first iteration of: call vect_set_loop_controls_directly. (2) vect_set_loop_controls_directly calculates "step" as in your patch. If rgc has 1 control, this step is the SSA name created for that control. Otherwise the step is a fresh SSA name, as in your patch. (3) vect_set_loop_controls_directly stores this step somewhere for later use, probably in LOOP_VINFO. Let's use "S" to refer to this stored step. (4) After the vect_set_loop_controls_directly call above, and outside the "if" statement that now contains vect_set_loop_controls_directly, check whether rgc->controls.length () > 1. If so, use vect_adjust_loop_lens_control to set the controls based on S. Then the only caller of vect_adjust_loop_lens_control is vect_set_loop_condition_partial_vectors. And the starting step for vect_adjust_loop_lens_control is always S. This patch has well tested for single-rgroup and multiple-rgroup (SLP) and passed all testcase in RISC-V port. Signed-off-by: Ju-Zhe Zhong Co-Authored-By: Richard Sandiford gcc/ChangeLog: * tree-vect-loop-manip.cc (vect_adjust_loop_lens_control): New function. (vect_set_loop_controls_directly): Add decrement IV support. (vect_set_loop_condition_partial_vectors): Ditto. * tree-vect-loop.cc (_loop_vec_info::_loop_vec_info): New variable. * tree-vectorizer.h (LOOP_VINFO_USING_DECREMENTING_IV_P): New macro. gcc/testsuite/ChangeLog: * gcc.target/riscv/rvv/autovec/partial/multiple_rgroup-3.c: New test. * gcc.target/riscv/rvv/autovec/partial/multiple_rgroup-4.c: New test. * gcc.target/riscv/rvv/autovec/partial/multiple_rgroup_run-3.c: New test. * gcc.target/riscv/rvv/autovec/partial/multiple_rgroup_run-4.c: New test. --- gcc/tree-vectorizer.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'gcc/tree-vectorizer.h') diff --git a/gcc/tree-vectorizer.h b/gcc/tree-vectorizer.h index 02d2ad6..fba09b9 100644 --- a/gcc/tree-vectorizer.h +++ b/gcc/tree-vectorizer.h @@ -818,6 +818,13 @@ public: the vector loop can handle fewer than VF scalars. */ bool using_partial_vectors_p; + /* True if we've decided to use a decrementing loop control IV that counts + scalars. This can be done for any loop that: + + (a) uses length "controls"; and + (b) can iterate more than once. */ + bool using_decrementing_iv_p; + /* True if we've decided to use partially-populated vectors for the epilogue of loop. */ bool epil_using_partial_vectors_p; @@ -890,6 +897,7 @@ public: #define LOOP_VINFO_VECTORIZABLE_P(L) (L)->vectorizable #define LOOP_VINFO_CAN_USE_PARTIAL_VECTORS_P(L) (L)->can_use_partial_vectors_p #define LOOP_VINFO_USING_PARTIAL_VECTORS_P(L) (L)->using_partial_vectors_p +#define LOOP_VINFO_USING_DECREMENTING_IV_P(L) (L)->using_decrementing_iv_p #define LOOP_VINFO_EPIL_USING_PARTIAL_VECTORS_P(L) \ (L)->epil_using_partial_vectors_p #define LOOP_VINFO_PARTIAL_LOAD_STORE_BIAS(L) (L)->partial_load_store_bias -- cgit v1.1