Hi Haochen Gui, It seems that the commit caused lots of test case fail on x86 platforms:
https://gcc.gnu.org/pipermail/gcc-regression/2023-October/078379.html https://gcc.gnu.org/pipermail/gcc-regression/2023-October/078380.html https://gcc.gnu.org/pipermail/gcc-regression/2023-October/078381.html https://gcc.gnu.org/pipermail/gcc-regression/2023-October/078382.html https://gcc.gnu.org/pipermail/gcc-regression/2023-October/078383.html https://gcc.gnu.org/pipermail/gcc-regression/2023-October/078384.html Please help verify that if we need some testcase change or we get bug here. A simple reproducer under build folder is: make check RUNTESTFLAGS="i386.exp=g++.target/i386/pr80566-2.C --target_board='unix{-m64\ -march=cascadelake,-m32\ -march=cascadelake,-m32,-m64}'" Thx, Haochen > -----Original Message----- > From: HAO CHEN GUI <guih...@linux.ibm.com> > Sent: Monday, October 23, 2023 9:30 AM > To: Richard Sandiford <richard.sandif...@arm.com> > Cc: gcc-patches <gcc-patches@gcc.gnu.org> > Subject: Re: [PATCH-1v4, expand] Enable vector mode for compare_by_pieces > [PR111449] > > Committed as r14-4835. > > https://gcc.gnu.org/g:f08ca5903c7a02b450b93143467f70b9fd8e0085 > > Thanks > Gui Haochen > > 在 2023/10/20 16:49, Richard Sandiford 写道: > > HAO CHEN GUI <guih...@linux.ibm.com> writes: > >> Hi, > >> Vector mode instructions are efficient for compare on some targets. > >> This patch enables vector mode for compare_by_pieces. Two help > >> functions are added to check if vector mode is available for certain > >> by pieces operations and if if optabs exists for the mode and certain > >> by pieces operations. One member is added in class op_by_pieces_d to > >> record the type of operations. > >> > >> The test case is in the second patch which is rs6000 specific. > >> > >> Compared to last version, the main change is to add a target hook > >> check - scalar_mode_supported_p when retrieving the available scalar > >> modes. The mode which is not supported for a target should be skipped. > >> (e.g. TImode on ppc). Also some function names and comments are refined > >> according to reviewer's advice. > >> > >> Bootstrapped and tested on x86 and powerpc64-linux BE and LE with no > >> regressions. > >> > >> Thanks > >> Gui Haochen > >> > >> ChangeLog > >> Expand: Enable vector mode for by pieces compares > >> > >> Vector mode compare instructions are efficient for equality compare on > >> rs6000. This patch refactors the codes of by pieces operation to enable > >> vector mode for compare. > >> > >> gcc/ > >> PR target/111449 > >> * expr.cc (can_use_qi_vectors): New function to return true if > >> we know how to implement OP using vectors of bytes. > >> (qi_vector_mode_supported_p): New function to check if optabs > >> exists for the mode and certain by pieces operations. > >> (widest_fixed_size_mode_for_size): Replace the second argument > >> with the type of by pieces operations. Call can_use_qi_vectors > >> and qi_vector_mode_supported_p to do the check. Call > >> scalar_mode_supported_p to check if the scalar mode is supported. > >> (by_pieces_ninsns): Pass the type of by pieces operation to > >> widest_fixed_size_mode_for_size. > >> (class op_by_pieces_d): Remove m_qi_vector_mode. Add m_op to > >> record the type of by pieces operations. > >> (op_by_pieces_d::op_by_pieces_d): Change last argument to the > >> type of by pieces operations, initialize m_op with it. Pass > >> m_op to function widest_fixed_size_mode_for_size. > >> (op_by_pieces_d::get_usable_mode): Pass m_op to function > >> widest_fixed_size_mode_for_size. > >> (op_by_pieces_d::smallest_fixed_size_mode_for_size): Call > >> can_use_qi_vectors and qi_vector_mode_supported_p to do the > >> check. > >> (op_by_pieces_d::run): Pass m_op to function > >> widest_fixed_size_mode_for_size. > >> (move_by_pieces_d::move_by_pieces_d): Set m_op to > MOVE_BY_PIECES. > >> (store_by_pieces_d::store_by_pieces_d): Set m_op with the op. > >> (can_store_by_pieces): Pass the type of by pieces operations to > >> widest_fixed_size_mode_for_size. > >> (clear_by_pieces): Initialize class store_by_pieces_d with > >> CLEAR_BY_PIECES. > >> (compare_by_pieces_d::compare_by_pieces_d): Set m_op to > >> COMPARE_BY_PIECES. > > > > OK, thanks. And thanks for your patience. > > > > Richard > > > >> patch.diff > >> diff --git a/gcc/expr.cc b/gcc/expr.cc > >> index 2c9930ec674..ad5f9dd8ec2 100644 > >> --- a/gcc/expr.cc > >> +++ b/gcc/expr.cc > >> @@ -988,18 +988,44 @@ alignment_for_piecewise_move (unsigned int > max_pieces, unsigned int align) > >> return align; > >> } > >> > >> -/* Return the widest QI vector, if QI_MODE is true, or integer mode > >> - that is narrower than SIZE bytes. */ > >> +/* Return true if we know how to implement OP using vectors of bytes. */ > >> +static bool > >> +can_use_qi_vectors (by_pieces_operation op) > >> +{ > >> + return (op == COMPARE_BY_PIECES > >> + || op == SET_BY_PIECES > >> + || op == CLEAR_BY_PIECES); > >> +} > >> + > >> +/* Return true if optabs exists for the mode and certain by pieces > >> + operations. */ > >> +static bool > >> +qi_vector_mode_supported_p (fixed_size_mode mode, > by_pieces_operation op) > >> +{ > >> + if ((op == SET_BY_PIECES || op == CLEAR_BY_PIECES) > >> + && optab_handler (vec_duplicate_optab, mode) != > CODE_FOR_nothing) > >> + return true; > >> + > >> + if (op == COMPARE_BY_PIECES > >> + && optab_handler (mov_optab, mode) != CODE_FOR_nothing > >> + && can_compare_p (EQ, mode, ccp_jump)) > >> + return true; > >> > >> + return false; > >> +} > >> + > >> +/* Return the widest mode that can be used to perform part of an > >> + operation OP on SIZE bytes. Try to use QI vector modes where > >> + possible. */ > >> static fixed_size_mode > >> -widest_fixed_size_mode_for_size (unsigned int size, bool qi_vector) > >> +widest_fixed_size_mode_for_size (unsigned int size, by_pieces_operation > op) > >> { > >> fixed_size_mode result = NARROWEST_INT_MODE; > >> > >> gcc_checking_assert (size > 1); > >> > >> /* Use QI vector only if size is wider than a WORD. */ > >> - if (qi_vector && size > UNITS_PER_WORD) > >> + if (can_use_qi_vectors (op) && size > UNITS_PER_WORD) > >> { > >> machine_mode mode; > >> fixed_size_mode candidate; > >> @@ -1009,8 +1035,7 @@ widest_fixed_size_mode_for_size (unsigned int > size, bool qi_vector) > >> { > >> if (GET_MODE_SIZE (candidate) >= size) > >> break; > >> - if (optab_handler (vec_duplicate_optab, candidate) > >> - != CODE_FOR_nothing) > >> + if (qi_vector_mode_supported_p (candidate, op)) > >> result = candidate; > >> } > >> > >> @@ -1019,9 +1044,14 @@ widest_fixed_size_mode_for_size (unsigned > int size, bool qi_vector) > >> } > >> > >> opt_scalar_int_mode tmode; > >> + scalar_int_mode mode; > >> FOR_EACH_MODE_IN_CLASS (tmode, MODE_INT) > >> - if (GET_MODE_SIZE (tmode.require ()) < size) > >> - result = tmode.require (); > >> + { > >> + mode = tmode.require (); > >> + if (GET_MODE_SIZE (mode) < size > >> + && targetm.scalar_mode_supported_p (mode)) > >> + result = mode; > >> + } > >> > >> return result; > >> } > >> @@ -1061,8 +1091,7 @@ by_pieces_ninsns (unsigned HOST_WIDE_INT l, > unsigned int align, > >> { > >> /* NB: Round up L and ALIGN to the widest integer mode for > >> MAX_SIZE. */ > >> - mode = widest_fixed_size_mode_for_size (max_size, > >> - op == SET_BY_PIECES); > >> + mode = widest_fixed_size_mode_for_size (max_size, op); > >> if (optab_handler (mov_optab, mode) != CODE_FOR_nothing) > >> { > >> unsigned HOST_WIDE_INT up = ROUND_UP (l, GET_MODE_SIZE > (mode)); > >> @@ -1076,8 +1105,7 @@ by_pieces_ninsns (unsigned HOST_WIDE_INT l, > unsigned int align, > >> > >> while (max_size > 1 && l > 0) > >> { > >> - mode = widest_fixed_size_mode_for_size (max_size, > >> - op == SET_BY_PIECES); > >> + mode = widest_fixed_size_mode_for_size (max_size, op); > >> enum insn_code icode; > >> > >> unsigned int modesize = GET_MODE_SIZE (mode); > >> @@ -1317,8 +1345,8 @@ class op_by_pieces_d > >> bool m_push; > >> /* True if targetm.overlap_op_by_pieces_p () returns true. */ > >> bool m_overlap_op_by_pieces; > >> - /* True if QI vector mode can be used. */ > >> - bool m_qi_vector_mode; > >> + /* The type of operation that we're performing. */ > >> + by_pieces_operation m_op; > >> > >> /* Virtual functions, overriden by derived classes for the specific > >> operation. */ > >> @@ -1331,7 +1359,7 @@ class op_by_pieces_d > >> public: > >> op_by_pieces_d (unsigned int, rtx, bool, rtx, bool, by_pieces_constfn, > >> void *, unsigned HOST_WIDE_INT, unsigned int, bool, > >> - bool = false); > >> + by_pieces_operation); > >> void run (); > >> }; > >> > >> @@ -1349,11 +1377,11 @@ op_by_pieces_d::op_by_pieces_d (unsigned > int max_pieces, rtx to, > >> void *from_cfn_data, > >> unsigned HOST_WIDE_INT len, > >> unsigned int align, bool push, > >> - bool qi_vector_mode) > >> + by_pieces_operation op) > >> : m_to (to, to_load, NULL, NULL), > >> m_from (from, from_load, from_cfn, from_cfn_data), > >> m_len (len), m_max_size (max_pieces + 1), > >> - m_push (push), m_qi_vector_mode (qi_vector_mode) > >> + m_push (push), m_op (op) > >> { > >> int toi = m_to.get_addr_inc (); > >> int fromi = m_from.get_addr_inc (); > >> @@ -1375,8 +1403,7 @@ op_by_pieces_d::op_by_pieces_d (unsigned int > max_pieces, rtx to, > >> { > >> /* Find the mode of the largest comparison. */ > >> fixed_size_mode mode > >> - = widest_fixed_size_mode_for_size (m_max_size, > >> - m_qi_vector_mode); > >> + = widest_fixed_size_mode_for_size (m_max_size, m_op); > >> > >> m_from.decide_autoinc (mode, m_reverse, len); > >> m_to.decide_autoinc (mode, m_reverse, len); > >> @@ -1401,7 +1428,7 @@ op_by_pieces_d::get_usable_mode > (fixed_size_mode mode, unsigned int len) > >> if (len >= size && prepare_mode (mode, m_align)) > >> break; > >> /* widest_fixed_size_mode_for_size checks SIZE > 1. */ > >> - mode = widest_fixed_size_mode_for_size (size, m_qi_vector_mode); > >> + mode = widest_fixed_size_mode_for_size (size, m_op); > >> } > >> while (1); > >> return mode; > >> @@ -1414,7 +1441,7 @@ fixed_size_mode > >> op_by_pieces_d::smallest_fixed_size_mode_for_size (unsigned int size) > >> { > >> /* Use QI vector only for > size of WORD. */ > >> - if (m_qi_vector_mode && size > UNITS_PER_WORD) > >> + if (can_use_qi_vectors (m_op) && size > UNITS_PER_WORD) > >> { > >> machine_mode mode; > >> fixed_size_mode candidate; > >> @@ -1427,8 +1454,7 @@ > op_by_pieces_d::smallest_fixed_size_mode_for_size (unsigned int size) > >> break; > >> > >> if (GET_MODE_SIZE (candidate) >= size > >> - && (optab_handler (vec_duplicate_optab, candidate) > >> - != CODE_FOR_nothing)) > >> + && qi_vector_mode_supported_p (candidate, m_op)) > >> return candidate; > >> } > >> } > >> @@ -1451,7 +1477,7 @@ op_by_pieces_d::run () > >> > >> /* widest_fixed_size_mode_for_size checks M_MAX_SIZE > 1. */ > >> fixed_size_mode mode > >> - = widest_fixed_size_mode_for_size (m_max_size, m_qi_vector_mode); > >> + = widest_fixed_size_mode_for_size (m_max_size, m_op); > >> mode = get_usable_mode (mode, length); > >> > >> by_pieces_prev to_prev = { nullptr, mode }; > >> @@ -1516,8 +1542,7 @@ op_by_pieces_d::run () > >> else > >> { > >> /* widest_fixed_size_mode_for_size checks SIZE > 1. */ > >> - mode = widest_fixed_size_mode_for_size (size, > >> - m_qi_vector_mode); > >> + mode = widest_fixed_size_mode_for_size (size, m_op); > >> mode = get_usable_mode (mode, length); > >> } > >> } > >> @@ -1543,7 +1568,7 @@ class move_by_pieces_d : public > op_by_pieces_d > >> move_by_pieces_d (rtx to, rtx from, unsigned HOST_WIDE_INT len, > >> unsigned int align) > >> : op_by_pieces_d (MOVE_MAX_PIECES, to, false, from, true, NULL, > >> - NULL, len, align, PUSHG_P (to)) > >> + NULL, len, align, PUSHG_P (to), MOVE_BY_PIECES) > >> { > >> } > >> rtx finish_retmode (memop_ret); > >> @@ -1632,15 +1657,16 @@ move_by_pieces (rtx to, rtx from, unsigned > HOST_WIDE_INT len, > >> class store_by_pieces_d : public op_by_pieces_d > >> { > >> insn_gen_fn m_gen_fun; > >> + > >> void generate (rtx, rtx, machine_mode) final override; > >> bool prepare_mode (machine_mode, unsigned int) final override; > >> > >> public: > >> store_by_pieces_d (rtx to, by_pieces_constfn cfn, void *cfn_data, > >> unsigned HOST_WIDE_INT len, unsigned int align, > >> - bool qi_vector_mode) > >> + by_pieces_operation op) > >> : op_by_pieces_d (STORE_MAX_PIECES, to, false, NULL_RTX, true, cfn, > >> - cfn_data, len, align, false, qi_vector_mode) > >> + cfn_data, len, align, false, op) > >> { > >> } > >> rtx finish_retmode (memop_ret); > >> @@ -1729,8 +1755,8 @@ can_store_by_pieces (unsigned > HOST_WIDE_INT len, > >> max_size = STORE_MAX_PIECES + 1; > >> while (max_size > 1 && l > 0) > >> { > >> - fixed_size_mode mode > >> - = widest_fixed_size_mode_for_size (max_size, memsetp); > >> + auto op = memsetp ? SET_BY_PIECES : STORE_BY_PIECES; > >> + auto mode = widest_fixed_size_mode_for_size (max_size, op); > >> > >> icode = optab_handler (mov_optab, mode); > >> if (icode != CODE_FOR_nothing > >> @@ -1793,7 +1819,7 @@ store_by_pieces (rtx to, unsigned > HOST_WIDE_INT len, > >> optimize_insn_for_speed_p ())); > >> > >> store_by_pieces_d data (to, constfun, constfundata, len, align, > >> - memsetp); > >> + memsetp ? SET_BY_PIECES : STORE_BY_PIECES); > >> data.run (); > >> > >> if (retmode != RETURN_BEGIN) > >> @@ -1814,7 +1840,7 @@ clear_by_pieces (rtx to, unsigned > HOST_WIDE_INT len, unsigned int align) > >> /* Use builtin_memset_read_str to support vector mode broadcast. */ > >> char c = 0; > >> store_by_pieces_d data (to, builtin_memset_read_str, &c, len, align, > >> - true); > >> + CLEAR_BY_PIECES); > >> data.run (); > >> } > >> > >> @@ -1832,12 +1858,13 @@ class compare_by_pieces_d : public > op_by_pieces_d > >> void generate (rtx, rtx, machine_mode) final override; > >> bool prepare_mode (machine_mode, unsigned int) final override; > >> void finish_mode (machine_mode) final override; > >> + > >> public: > >> compare_by_pieces_d (rtx op0, rtx op1, by_pieces_constfn op1_cfn, > >> void *op1_cfn_data, HOST_WIDE_INT len, int align, > >> rtx_code_label *fail_label) > >> : op_by_pieces_d (COMPARE_MAX_PIECES, op0, true, op1, true, > op1_cfn, > >> - op1_cfn_data, len, align, false) > >> + op1_cfn_data, len, align, false, COMPARE_BY_PIECES) > >> { > >> m_fail_label = fail_label; > >> }
