From e09173d84dabd186ad2463f47350c1bcabfeab8f Mon Sep 17 00:00:00 2001 From: Tamar Christina Date: Thu, 14 Jan 2021 20:57:17 +0000 Subject: [PATCH] slp: support complex multiply and complex multiply conjugate This adds support for complex multiply and complex multiply and accumulate to the vect pattern detector. Example of instructions matched: #include #include #define N 200 #define ROT #define TYPE float #define TYPE2 float void g (TYPE2 complex a[restrict N], TYPE complex b[restrict N], TYPE complex c[restrict N]) { for (int i=0; i < N; i++) { c[i] = a[i] * (b[i] ROT); } } void g_f1 (TYPE2 complex a[restrict N], TYPE complex b[restrict N], TYPE complex c[restrict N]) { for (int i=0; i < N; i++) { c[i] = conjf (a[i]) * (b[i] ROT); } } void g_s1 (TYPE2 complex a[restrict N], TYPE complex b[restrict N], TYPE complex c[restrict N]) { for (int i=0; i < N; i++) { c[i] = a[i] * conjf (b[i] ROT); } } gcc/ChangeLog: * internal-fn.def (COMPLEX_MUL, COMPLEX_MUL_CONJ): New. * optabs.def (cmul_optab, cmul_conj_optab): New. * doc/md.texi: Document them. * tree-vect-slp-patterns.c (vect_match_call_complex_mla, vect_normalize_conj_loc, is_eq_or_top, vect_validate_multiplication, vect_build_combine_node, class complex_mul_pattern, complex_mul_pattern::matches, complex_mul_pattern::recognize, complex_mul_pattern::build): New. --- gcc/doc/md.texi | 44 +++++ gcc/internal-fn.def | 2 + gcc/optabs.def | 2 + gcc/tree-vect-slp-patterns.c | 368 +++++++++++++++++++++++++++++++++++ 4 files changed, 416 insertions(+) diff --git a/gcc/doc/md.texi b/gcc/doc/md.texi index a4435df8a13..60e8c94810a 100644 --- a/gcc/doc/md.texi +++ b/gcc/doc/md.texi @@ -6202,6 +6202,50 @@ The operation is only supported for vector modes @var{m}. This pattern is not allowed to @code{FAIL}. +@cindex @code{cmul@var{m}4} instruction pattern +@item @samp{cmul@var{m}4} +Perform a vector multiply that is semantically the same as multiply of +complex numbers. + +@smallexample + complex TYPE c[N]; + complex TYPE a[N]; + complex TYPE b[N]; + for (int i = 0; i < N; i += 1) + @{ + c[i] = a[i] * b[i]; + @} +@end smallexample + +In GCC lane ordering the real part of the number must be in the even lanes with +the imaginary part in the odd lanes. + +The operation is only supported for vector modes @var{m}. + +This pattern is not allowed to @code{FAIL}. + +@cindex @code{cmul_conj@var{m}4} instruction pattern +@item @samp{cmul_conj@var{m}4} +Perform a vector multiply by conjugate that is semantically the same as a +multiply of complex numbers where the second multiply arguments is conjugated. + +@smallexample + complex TYPE c[N]; + complex TYPE a[N]; + complex TYPE b[N]; + for (int i = 0; i < N; i += 1) + @{ + c[i] = a[i] * conj (b[i]); + @} +@end smallexample + +In GCC lane ordering the real part of the number must be in the even lanes with +the imaginary part in the odd lanes. + +The operation is only supported for vector modes @var{m}. + +This pattern is not allowed to @code{FAIL}. + @cindex @code{ffs@var{m}2} instruction pattern @item @samp{ffs@var{m}2} Store into operand 0 one plus the index of the least significant 1-bit diff --git a/gcc/internal-fn.def b/gcc/internal-fn.def index 19016ce109f..e3e4fe5ebad 100644 --- a/gcc/internal-fn.def +++ b/gcc/internal-fn.def @@ -279,6 +279,8 @@ DEF_INTERNAL_FLT_FLOATN_FN (FMAX, ECF_CONST, fmax, binary) DEF_INTERNAL_OPTAB_FN (XORSIGN, ECF_CONST, xorsign, binary) DEF_INTERNAL_OPTAB_FN (COMPLEX_ADD_ROT90, ECF_CONST, cadd90, binary) DEF_INTERNAL_OPTAB_FN (COMPLEX_ADD_ROT270, ECF_CONST, cadd270, binary) +DEF_INTERNAL_OPTAB_FN (COMPLEX_MUL, ECF_CONST, cmul, binary) +DEF_INTERNAL_OPTAB_FN (COMPLEX_MUL_CONJ, ECF_CONST, cmul_conj, binary) /* FP scales. */ diff --git a/gcc/optabs.def b/gcc/optabs.def index a6958418645..fcc27d00dba 100644 --- a/gcc/optabs.def +++ b/gcc/optabs.def @@ -292,6 +292,8 @@ OPTAB_D (copysign_optab, "copysign$F$a3") OPTAB_D (xorsign_optab, "xorsign$F$a3") OPTAB_D (cadd90_optab, "cadd90$a3") OPTAB_D (cadd270_optab, "cadd270$a3") +OPTAB_D (cmul_optab, "cmul$a3") +OPTAB_D (cmul_conj_optab, "cmul_conj$a3") OPTAB_D (cos_optab, "cos$a2") OPTAB_D (cosh_optab, "cosh$a2") OPTAB_D (exp10_optab, "exp10$a2") diff --git a/gcc/tree-vect-slp-patterns.c b/gcc/tree-vect-slp-patterns.c index c4fa269baa3..dc96be51dfe 100644 --- a/gcc/tree-vect-slp-patterns.c +++ b/gcc/tree-vect-slp-patterns.c @@ -717,6 +717,374 @@ complex_add_pattern::recognize (slp_tree_to_load_perm_map_t *perm_cache, return new complex_add_pattern (node, &ops, ifn); } +/******************************************************************************* + * complex_mul_pattern + ******************************************************************************/ + +/* Helper function of that looks for a match in the CHILDth child of NODE. The + child used is stored in RES. + + If the match is successful then ARGS will contain the operands matched + and the complex_operation_t type is returned. If match is not successful + then CMPLX_NONE is returned and ARGS is left unmodified. */ + +static inline complex_operation_t +vect_match_call_complex_mla (slp_tree node, unsigned child, + vec *args = NULL, slp_tree *res = NULL) +{ + gcc_assert (child < SLP_TREE_CHILDREN (node).length ()); + + slp_tree data = SLP_TREE_CHILDREN (node)[child]; + + if (res) + *res = data; + + return vect_detect_pair_op (data, false, args); +} + +/* Check to see if either of the trees in ARGS are a NEGATE_EXPR. If the first + child (args[0]) is a NEGATE_EXPR then NEG_FIRST_P is set to TRUE. + + If a negate is found then the values in ARGS are reordered such that the + negate node is always the second one and the entry is replaced by the child + of the negate node. */ + +static inline bool +vect_normalize_conj_loc (vec args, bool *neg_first_p = NULL) +{ + gcc_assert (args.length () == 2); + bool neg_found = false; + + if (vect_match_expression_p (args[0], NEGATE_EXPR)) + { + std::swap (args[0], args[1]); + neg_found = true; + if (neg_first_p) + *neg_first_p = true; + } + else if (vect_match_expression_p (args[1], NEGATE_EXPR)) + { + neg_found = true; + if (neg_first_p) + *neg_first_p = false; + } + + if (neg_found) + args[1] = SLP_TREE_CHILDREN (args[1])[0]; + + return neg_found; +} + +/* Helper function to check if PERM is KIND or PERM_TOP. */ + +static inline bool +is_eq_or_top (complex_load_perm_t perm, complex_perm_kinds_t kind) +{ + return perm.first == kind || perm.first == PERM_TOP; +} + +/* Helper function that checks to see if LEFT_OP and RIGHT_OP are both MULT_EXPR + nodes but also that they represent an operation that is either a complex + multiplication or a complex multiplication by conjugated value. + + Of the negation is expected to be in the first half of the tree (As required + by an FMS pattern) then NEG_FIRST is true. If the operation is a conjugate + operation then CONJ_FIRST_OPERAND is set to indicate whether the first or + second operand contains the conjugate operation. */ + +static inline bool +vect_validate_multiplication (slp_tree_to_load_perm_map_t *perm_cache, + vec left_op, vec right_op, + bool neg_first, bool *conj_first_operand, + bool fms) +{ + /* The presence of a negation indicates that we have either a conjugate or a + rotation. We need to distinguish which one. */ + *conj_first_operand = false; + complex_perm_kinds_t kind; + + /* Complex conjugates have the negation on the imaginary part of the + number where rotations affect the real component. So check if the + negation is on a dup of lane 1. */ + if (fms) + { + /* Canonicalization for fms is not consistent. So have to test both + variants to be sure. This needs to be fixed in the mid-end so + this part can be simpler. */ + kind = linear_loads_p (perm_cache, right_op[0]).first; + if (!((kind == PERM_ODDODD + && is_eq_or_top (linear_loads_p (perm_cache, right_op[1]), + PERM_ODDEVEN)) + || (kind == PERM_ODDEVEN + && is_eq_or_top (linear_loads_p (perm_cache, right_op[1]), + PERM_ODDODD)))) + return false; + } + else + { + if (linear_loads_p (perm_cache, right_op[1]).first != PERM_ODDODD + && !is_eq_or_top (linear_loads_p (perm_cache, right_op[0]), + PERM_ODDEVEN)) + return false; + } + + /* Deal with differences in indexes. */ + int index1 = fms ? 1 : 0; + int index2 = fms ? 0 : 1; + + /* Check if the conjugate is on the second first or second operand. The + order of the node with the conjugate value determines this, and the dup + node must be one of lane 0 of the same DR as the neg node. */ + kind = linear_loads_p (perm_cache, left_op[index1]).first; + if (kind == PERM_TOP) + { + if (linear_loads_p (perm_cache, left_op[index2]).first == PERM_EVENODD) + return true; + } + else if (kind == PERM_EVENODD) + { + if ((kind = linear_loads_p (perm_cache, left_op[index2]).first) == PERM_EVENODD) + return false; + } + else if (!neg_first) + *conj_first_operand = true; + else + return false; + + if (kind != PERM_EVENEVEN) + return false; + + return true; +} + +/* Helper function to help distinguish between a conjugate and a rotation in a + complex multiplication. The operations have similar shapes but the order of + the load permutes are different. This function returns TRUE when the order + is consistent with a multiplication or multiplication by conjugated + operand but returns FALSE if it's a multiplication by rotated operand. */ + +static inline bool +vect_validate_multiplication (slp_tree_to_load_perm_map_t *perm_cache, + vec op, complex_perm_kinds_t permKind) +{ + /* The left node is the more common case, test it first. */ + if (!is_eq_or_top (linear_loads_p (perm_cache, op[0]), permKind)) + { + if (!is_eq_or_top (linear_loads_p (perm_cache, op[1]), permKind)) + return false; + } + return true; +} + +/* This function combines two nodes containing only even and only odd lanes + together into a single node which contains the nodes in even/odd order + by using a lane permute. + + The lanes in EVEN and ODD are duplicated 2 times inside the vectors. + So for a lanes = 4 EVEN contains {EVEN1, EVEN1, EVEN2, EVEN2}. + + The tree REPRESENTATION is taken from the supplied REP along with the + vectype which must be the same between all three nodes. +*/ + +static slp_tree +vect_build_combine_node (slp_tree even, slp_tree odd, slp_tree rep) +{ + vec > perm; + perm.create (SLP_TREE_LANES (rep)); + + for (unsigned x = 0; x < SLP_TREE_LANES (rep); x+=2) + { + perm.quick_push (std::make_pair (0, x)); + perm.quick_push (std::make_pair (1, x+1)); + } + + slp_tree vnode = vect_create_new_slp_node (2, SLP_TREE_CODE (even)); + SLP_TREE_CODE (vnode) = VEC_PERM_EXPR; + SLP_TREE_LANE_PERMUTATION (vnode) = perm; + + SLP_TREE_CHILDREN (vnode).create (2); + SLP_TREE_CHILDREN (vnode).quick_push (even); + SLP_TREE_CHILDREN (vnode).quick_push (odd); + SLP_TREE_REF_COUNT (even)++; + SLP_TREE_REF_COUNT (odd)++; + SLP_TREE_REF_COUNT (vnode) = 1; + + SLP_TREE_LANES (vnode) = SLP_TREE_LANES (rep); + gcc_assert (perm.length () == SLP_TREE_LANES (vnode)); + /* Representation is set to that of the current node as the vectorizer + can't deal with VEC_PERMs with no representation, as would be the + case with invariants. */ + SLP_TREE_REPRESENTATIVE (vnode) = SLP_TREE_REPRESENTATIVE (rep); + SLP_TREE_VECTYPE (vnode) = SLP_TREE_VECTYPE (rep); + return vnode; +} + +class complex_mul_pattern : public complex_pattern +{ + protected: + complex_mul_pattern (slp_tree *node, vec *m_ops, internal_fn ifn) + : complex_pattern (node, m_ops, ifn) + { + this->m_num_args = 2; + } + + public: + void build (vec_info *); + static internal_fn + matches (complex_operation_t op, slp_tree_to_load_perm_map_t *, slp_tree *, + vec *); + + static vect_pattern* + recognize (slp_tree_to_load_perm_map_t *, slp_tree *); + + static vect_pattern* + mkInstance (slp_tree *node, vec *m_ops, internal_fn ifn) + { + return new complex_mul_pattern (node, m_ops, ifn); + } + +}; + +/* Pattern matcher for trying to match complex multiply pattern in SLP tree + If the operation matches then IFN is set to the operation it matched + and the arguments to the two replacement statements are put in m_ops. + + If no match is found then IFN is set to IFN_LAST and m_ops is unchanged. + + This function matches the patterns shaped as: + + double ax = (b[i+1] * a[i]); + double bx = (a[i+1] * b[i]); + + c[i] = c[i] - ax; + c[i+1] = c[i+1] + bx; + + If a match occurred then TRUE is returned, else FALSE. The initial match is + expected to be in OP1 and the initial match operands in args0. */ + +internal_fn +complex_mul_pattern::matches (complex_operation_t op, + slp_tree_to_load_perm_map_t *perm_cache, + slp_tree *node, vec *ops) +{ + internal_fn ifn = IFN_LAST; + + if (op != MINUS_PLUS) + return IFN_LAST; + + slp_tree root = *node; + /* First two nodes must be a multiply. */ + auto_vec muls; + if (vect_match_call_complex_mla (root, 0) != MULT_MULT + || vect_match_call_complex_mla (root, 1, &muls) != MULT_MULT) + return IFN_LAST; + + /* Now operand2+4 may lead to another expression. */ + auto_vec left_op, right_op; + left_op.safe_splice (SLP_TREE_CHILDREN (muls[0])); + right_op.safe_splice (SLP_TREE_CHILDREN (muls[1])); + + if (linear_loads_p (perm_cache, left_op[1]).first == PERM_ODDEVEN) + return IFN_LAST; + + bool neg_first = false; + bool conj_first_operand = false; + bool is_neg = vect_normalize_conj_loc (right_op, &neg_first); + + if (!is_neg) + { + /* A multiplication needs to multiply agains the real pair, otherwise + the pattern matches that of FMS. */ + if (!vect_validate_multiplication (perm_cache, left_op, PERM_EVENEVEN) + || vect_normalize_conj_loc (left_op)) + return IFN_LAST; + ifn = IFN_COMPLEX_MUL; + } + else if (is_neg) + { + if (!vect_validate_multiplication (perm_cache, left_op, right_op, + neg_first, &conj_first_operand, + false)) + return IFN_LAST; + + ifn = IFN_COMPLEX_MUL_CONJ; + } + + if (!vect_pattern_validate_optab (ifn, *node)) + return IFN_LAST; + + ops->truncate (0); + ops->create (3); + + complex_perm_kinds_t kind = linear_loads_p (perm_cache, left_op[0]).first; + if (kind == PERM_EVENODD) + { + ops->quick_push (left_op[1]); + ops->quick_push (right_op[1]); + ops->quick_push (left_op[0]); + } + else if (kind == PERM_TOP) + { + ops->quick_push (left_op[1]); + ops->quick_push (right_op[1]); + ops->quick_push (left_op[0]); + } + else if (kind == PERM_EVENEVEN && !conj_first_operand) + { + ops->quick_push (left_op[0]); + ops->quick_push (right_op[0]); + ops->quick_push (left_op[1]); + } + else + { + ops->quick_push (left_op[0]); + ops->quick_push (right_op[1]); + ops->quick_push (left_op[1]); + } + + return ifn; +} + +/* Attempt to recognize a complex mul pattern. */ + +vect_pattern* +complex_mul_pattern::recognize (slp_tree_to_load_perm_map_t *perm_cache, + slp_tree *node) +{ + auto_vec ops; + complex_operation_t op + = vect_detect_pair_op (*node, true, &ops); + internal_fn ifn + = complex_mul_pattern::matches (op, perm_cache, node, &ops); + if (ifn == IFN_LAST) + return NULL; + + return new complex_mul_pattern (node, &ops, ifn); +} + +/* Perform a replacement of the detected complex mul pattern with the new + instruction sequences. */ + +void +complex_mul_pattern::build (vec_info *vinfo) +{ + slp_tree node; + unsigned i; + FOR_EACH_VEC_ELT (SLP_TREE_CHILDREN (*this->m_node), i, node) + vect_free_slp_tree (node); + + /* First re-arrange the children. */ + SLP_TREE_CHILDREN (*this->m_node).reserve_exact (2); + SLP_TREE_CHILDREN (*this->m_node)[0] = this->m_ops[2]; + SLP_TREE_CHILDREN (*this->m_node)[1] = + vect_build_combine_node (this->m_ops[0], this->m_ops[1], *this->m_node); + SLP_TREE_REF_COUNT (this->m_ops[2])++; + + /* And then rewrite the node itself. */ + complex_pattern::build (vinfo); +} + /******************************************************************************* * Pattern matching definitions ******************************************************************************/ -- 2.30.2