2 * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief Lowering of high level constructs.
23 * @author Michael Beck
26 #ifndef FIRM_LOWERING_H
27 #define FIRM_LOWERING_H
29 #include "firm_types.h"
31 * A type telling where to add hidden parameters.
33 typedef enum add_hidden_params {
34 ADD_HIDDEN_ALWAYS_IN_FRONT = 0, /**< always add hidden parameters in front (default). */
35 ADD_HIDDEN_ALWAYS_LAST = 1, /**< always add hidden parameters last, did not work for variadic functions. */
36 ADD_HIDDEN_SMART = 2 /**< add hidden parameters last for non-variadic and first for variadic functions. */
40 * Additional flags for the lowering.
43 LF_NONE = 0, /**< no additional flags */
44 LF_COMPOUND_PARAM = 1, /**< lower calls with compound parameters */
45 LF_COMPOUND_RETURN = 2, /**< lower calls with compound returns */
46 LF_RETURN_HIDDEN = 4, /**< return the hidden address instead of void */
47 LF_SMALL_CMP_IN_REGS = 8 /**< return small compound values in registers */
50 /** Maximum number of registers that can be used to return compound values. */
51 #define MAX_REGISTER_RET_VAL 2
54 * A struct containing all control parameters for
55 * lower_compound_ret_calls().
58 int def_ptr_alignment; /**< Default alignment for data pointer. */
59 unsigned flags; /**< A bitmask of enum lowering_flags. */
60 add_hidden hidden_params; /**< Where to add hidden parameters. */
63 * A function returning a pointer type for a given type.
64 * If this pointer is NULL, a new pointer type is always created.
66 ir_type *(*find_pointer_type)(ir_type *e_type, ir_mode *mode, int alignment);
69 * If the LF_SMALL_CMP_IN_REGS flag is set, this function will be called
70 * to decide, whether a compound value should be returned in registers.
71 * This function must return the number of used registers and fill in the modes
72 * of the registers to use. Up to MAX_REGISTER_RET_VAL registers can be used.
74 int (*ret_compound_in_regs)(ir_type *compound_tp, ir_mode **modes);
78 * Lower calls with compound parameter and return types.
79 * This function does the following transformations:
81 * If LF_COMPOUND_PARAM is set:
83 * - Copy compound parameters to a new location on the callers
84 * stack and transmit the address of this new location
86 * If LF_COMPOUND_RETURN is set:
88 * - Adds a new (hidden) pointer parameter for
89 * any return compound type. The return type is replaced by void
90 * or if LOWERING_FLAGS_RETURN_HIDDEN is set by the address.
92 * - Use of the hidden parameters in the function code.
94 * - Change all calls to functions with compound return
95 * by providing space for the hidden parameter on the callers
98 * - Replace a possible block copy after the function call.
102 * - Changes the types of methods and calls to the lowered ones
104 * - lower all method types of existing entities
106 * In pseudo-code, the following transformation is done:
109 struct x ret = func(a, b);
118 * If the function returns only one possible result, the copy-on-return
119 * optimization is done, ie.
128 * is transformed into
131 void func(struct x *ret, a) {
136 * @param params A structure containing the control parameter for this
139 * During the transformation, pointer types must be created or reused.
140 * The caller can provide params->find_pointer_type for this task to
141 * reduce the number of created pointer types.
142 * If params->find_pointer_type is NULL, new pointer types
143 * are always created automatically.
145 void lower_calls_with_compounds(const lower_params_t *params);
148 * A callback type for creating an intrinsic entity for a given opcode.
150 * @param method the method type of the emulation function entity
151 * @param op the emulated ir_op
152 * @param imode the input mode of the emulated opcode
153 * @param omode the output mode of the emulated opcode
154 * @param context the context parameter
156 typedef ir_entity *(create_intrinsic_fkt)(ir_type *method, const ir_op *op,
157 const ir_mode *imode, const ir_mode *omode,
161 * The lowering parameter description.
163 typedef struct _lwrdw_param_t {
164 int enable; /**< if true lowering is enabled */
165 int little_endian; /**< if true should be lowered for little endian, else big endian */
166 ir_mode *high_signed; /**< the double word signed mode to be lowered, typically Ls */
167 ir_mode *high_unsigned; /**< the double word unsigned mode to be lowered, typically Lu */
168 ir_mode *low_signed; /**< the word signed mode to be used, typically Is */
169 ir_mode *low_unsigned; /**< the word unsigned mode to be used, typically Iu */
171 /** callback that creates the intrinsic entity */
172 create_intrinsic_fkt *create_intrinsic;
173 void *ctx; /**< context parameter for the creator function */
177 * Lower all double word operations.
179 void lower_dw_ops(const lwrdw_param_t *param);
182 * Default implementation. Context is unused.
184 ir_entity *def_create_intrinsic_fkt(ir_type *method, const ir_op *op,
185 const ir_mode *imode, const ir_mode *omode,
189 * Replaces SymConsts by a real constant if possible.
190 * Replace Sel nodes by address computation. Also resolves array access.
191 * Handle Bitfields by added And/Or calculations.
193 * @Note: There is NO lowering ob objects oriented types. This is highly compiler
194 * and ABI specific and should be placed directly in the compiler.
196 void lower_highlevel(void);
199 * An intrinsic mapper function.
201 * @param node the IR-node that will be mapped
202 * @param ctx a context
204 * @return non-zero if the call was mapped
206 typedef int (*i_mapper_func)(ir_node *node, void *ctx);
209 INTRINSIC_CALL = 0, /**< the record represents an intrinsic call */
210 INTRINSIC_INSTR /**< the record represents an intrinsic instruction */
214 * An intrinsic call record.
216 typedef struct _i_call_record {
217 enum ikind kind; /**< must be INTRINSIC_CALL */
218 ir_entity *i_ent; /**< the entity representing an intrinsic call */
219 i_mapper_func i_mapper; /**< the mapper function to call */
220 void *ctx; /**< mapper context */
221 void *link; /**< used in the construction algorithm, must be NULL */
225 * An intrinsic instruction record.
227 typedef struct _i_instr_record {
228 enum ikind kind; /**< must be INTRINSIC_INSTR */
229 ir_op *op; /**< the opcode that must be mapped. */
230 i_mapper_func i_mapper; /**< the mapper function to call */
231 void *ctx; /**< mapper context */
232 void *link; /**< used in the construction algorithm, must be NULL */
236 * An intrinsic record.
238 typedef union _i_record {
239 i_call_record i_call;
240 i_instr_record i_instr;
244 * Go through all graphs and map calls to intrinsic functions and instructions.
246 * Every call or instruction is reported to its mapper function,
247 * which is responsible for rebuilding the graph.
249 * current_ir_graph is always set.
251 * @param list an array of intrinsic map records
252 * @param length the length of the array
254 * @return number of found intrinsics.
256 unsigned lower_intrinsics(i_record *list, int length);
259 * A mapper for the integer absolute value: inttype abs(inttype v).
260 * Replaces the call by a Abs node.
264 int i_mapper_Abs(ir_node *call, void *ctx);
267 * A mapper for the alloca() function: pointer alloca(inttype size)
268 * Replaces the call by a Alloca(stack_alloc) node.
272 int i_mapper_Alloca(ir_node *call, void *ctx);
275 * A runtime routine description.
277 typedef struct _runtime_rt {
278 ir_entity *ent; /**< The entity representing the runtime routine. */
279 ir_mode *mode; /**< The operation mode of the mapped instruction. */
280 ir_mode *res_mode; /**< The result mode of the mapped instruction or NULL. */
281 long mem_proj_nr; /**< if >= 0, create a memory ProjM() */
282 long regular_proj_nr; /**< if >= 0, create a regular ProjX() */
283 long exc_proj_nr; /**< if >= 0, create a exception ProjX() */
284 long exc_mem_proj_nr; /**< if >= 0, create a exception memory ProjM() */
285 long res_proj_nr; /**< if >= 0, first result projection number */
289 * A mapper for mapping unsupported instructions to runtime calls.
290 * Maps a op(arg_0, ..., arg_n) into a call to a runtime function
291 * rt(arg_0, ..., arg_n).
293 * The mapping is only done, if the modes of all arguments matches the
294 * modes of rt's argument.
295 * Further, if op has a memory input, the generated Call uses it, else
297 * The pinned state of the Call will be set to the pinned state of op.
299 * Note that i_mapper_RuntimeCall() must be used with a i_instr_record.
301 * @return 1 if an op was mapped, 0 else
305 * - Maps signed Div nodes to calls to rt_Div():
307 runtime_rt rt_Div = {
308 ent("int rt_Div(int, int)"),
317 i_instr_record map_Div = {
320 i_mapper_RuntimeCall,
326 * - Maps ConvD(F) to calls to rt_Float2Div():
328 runtime_rt rt_Float2Double = {
329 ent("double rt_Float2Div(float)"),
330 get_type_mode("double"),
338 i_instr_record map_Float2Double = {
341 i_mapper_RuntimeCall,
347 int i_mapper_RuntimeCall(ir_node *node, runtime_rt *rt);
349 #endif /* FIRM_LOWERING_H */