### Introduce flip-flopping normalisations

```There are cases where we can normalize in 2 directions and both have
their merits. Just do both in this case. The frontend should at some
point set IRG_GRAPH_STATE_NORMALISATION2 to trigger the 2nd direction.```
parent b6a361cf
 ... ... @@ -514,6 +514,12 @@ typedef enum { IR_GRAPH_STATE_ARCH_DEP = 1U << 1, /**< should not construct more nodes which irarch potentially breaks down */ IR_GRAPH_STATE_BCONV_ALLOWED = 1U << 2, /**< Conv(mode_b) to Iu is allowed as set command */ IR_GRAPH_STATE_BAD_BLOCK = 1U << 3, /**< a node may have Bad in its block input */ /** * There are normalisations where there is no "best" representative. * In this case we first normalise into 1 direction (!NORMALISATION2) and * later in the other (NORMALISATION2). */ IR_GRAPH_STATE_NORMALISATION2 = 1U << 4, } ir_graph_state_t; ENUM_BITSET(ir_graph_state_t) ... ...
 ... ... @@ -2181,6 +2181,7 @@ restart: } DBG_OPT_ALGSIM0(oldn, n, FS_OPT_SUB_TO_ADD); return n; #if 0 } else if (is_Mul(b)) { /* a - (b * C) -> a + (b * -C) */ ir_node *m_right = get_Mul_right(b); if (is_Const(m_right)) { ... ... @@ -2199,6 +2200,7 @@ restart: return n; } } #endif } /* Beware of Sub(P, P) which cannot be optimized into a simple Minus ... */ ... ... @@ -2930,15 +2932,109 @@ static bool is_shiftop(const ir_node *n) return is_Shl(n) || is_Shr(n) || is_Shrs(n) || is_Rotl(n); } /** * normalisation: (x & c1) >> c2 to (x >> c2) & (c1 >> c2) * (we can use: * - and, or, xor instead of & * - Shl, Shr, Shrs, rotl instead of >> * (with a special case for Or/Xor + Shrs) * * This normalisation is good for things like x-(x&y) esp. in 186.crafty. */ static ir_node *transform_node_shift_bitop(ir_node *n) { ir_graph *irg = get_irn_irg(n); ir_node *right = get_binop_right(n); ir_mode *mode = get_irn_mode(n); ir_node *left; ir_node *bitop_left; ir_node *bitop_right; ir_op *op_left; ir_node *block; dbg_info *dbgi; ir_node *new_shift; ir_node *new_bitop; ir_node *new_const; ir_tarval *tv1; ir_tarval *tv2; ir_tarval *tv_shift; if (is_irg_state(irg, IR_GRAPH_STATE_NORMALISATION2)) return n; assert(is_Shrs(n) || is_Shr(n) || is_Shl(n) || is_Rotl(n)); if (!is_Const(right)) return n; left = get_binop_left(n); op_left = get_irn_op(left); if (op_left != op_And && op_left != op_Or && op_left != op_Eor) return n; /* doing it with Shrs is not legal if the Or/Eor affects the topmost bit */ if (is_Shrs(n) && (op_left == op_Or || op_left == op_Eor)) { /* TODO: test if sign bit is affectes */ return n; } bitop_right = get_binop_right(left); if (!is_Const(bitop_right)) return n; bitop_left = get_binop_left(left); block = get_nodes_block(n); dbgi = get_irn_dbg_info(n); tv1 = get_Const_tarval(bitop_right); tv2 = get_Const_tarval(right); assert(get_tarval_mode(tv1) == mode); if (is_Shl(n)) { new_shift = new_rd_Shl(dbgi, block, bitop_left, right, mode); tv_shift = tarval_shl(tv1, tv2); } else if (is_Shr(n)) { new_shift = new_rd_Shr(dbgi, block, bitop_left, right, mode); tv_shift = tarval_shr(tv1, tv2); } else if (is_Shrs(n)) { new_shift = new_rd_Shrs(dbgi, block, bitop_left, right, mode); tv_shift = tarval_shrs(tv1, tv2); } else { assert(is_Rotl(n)); new_shift = new_rd_Rotl(dbgi, block, bitop_left, right, mode); tv_shift = tarval_rotl(tv1, tv2); } assert(get_tarval_mode(tv_shift) == mode); irg = get_irn_irg(n); new_const = new_r_Const(irg, tv_shift); if (op_left == op_And) { new_bitop = new_rd_And(dbgi, block, new_shift, new_const, mode); } else if (op_left == op_Or) { new_bitop = new_rd_Or(dbgi, block, new_shift, new_const, mode); } else { assert(op_left == op_Eor); new_bitop = new_rd_Eor(dbgi, block, new_shift, new_const, mode); } return new_bitop; } /** * normalisation: (x >> c1) & c2 to (x & (c2<> c1 * (we can use: * - and, or, xor instead of & * - Shl, Shr, Shrs, rotl instead of >> * (with a special case for Or/Xor + Shrs) * * This normalisation is usually good for the backend since << C can often be * matched as address-mode. */ static ir_node *transform_node_bitop_shift(ir_node *n) { ir_graph *irg = get_irn_irg(n); ir_node *left = get_binop_left(n); ir_node *right = get_binop_right(n); ir_mode *mode = get_irn_mode(n); ... ... @@ -2947,7 +3043,6 @@ static ir_node *transform_node_bitop_shift(ir_node *n) ir_node *block; dbg_info *dbg_bitop; dbg_info *dbg_shift; ir_graph *irg; ir_node *new_bitop; ir_node *new_shift; ir_node *new_const; ... ... @@ -2955,6 +3050,9 @@ static ir_node *transform_node_bitop_shift(ir_node *n) ir_tarval *tv2; ir_tarval *tv_bitop; if (!is_irg_state(irg, IR_GRAPH_STATE_NORMALISATION2)) return n; assert(is_And(n) || is_Or(n) || is_Eor(n)); if (!is_Const(right) || !is_shiftop(left)) return n; ... ... @@ -5135,6 +5233,8 @@ static ir_node *transform_node_Shr(ir_node *n) n = transform_node_shift_modulo(n, new_rd_Shr); if (is_Shr(n)) n = transform_node_shl_shr(n); if (is_Shr(n)) n = transform_node_shift_bitop(n); return n; } /* transform_node_Shr */ ... ... @@ -5164,6 +5264,8 @@ static ir_node *transform_node_Shrs(ir_node *n) if (is_Shrs(n)) n = transform_node_shift_modulo(n, new_rd_Shrs); if (is_Shrs(n)) n = transform_node_shift_bitop(n); return n; } /* transform_node_Shrs */ ... ... @@ -5185,6 +5287,8 @@ static ir_node *transform_node_Shl(ir_node *n) n = transform_node_shift_modulo(n, new_rd_Shl); if (is_Shl(n)) n = transform_node_shl_shr(n); if (is_Shl(n)) n = transform_node_shift_bitop(n); return n; } /* transform_node_Shl */ ... ... @@ -5202,6 +5306,9 @@ static ir_node *transform_node_Rotl(ir_node *n) HANDLE_BINOP_PHI((eval_func) tarval_rotl, a, b, c, mode); n = transform_node_shift(n); if (is_Rotl(n)) n = transform_node_shift_bitop(n); return n; } /* transform_node_Rotl */ ... ...
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