1/**************************************************************************
2 *
3 * Copyright 2009 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28/**
29 * LLVM control flow build helpers.
30 *
31 * @author Jose Fonseca <jfonseca@vmware.com>
32 */
33
34#ifndef LP_BLD_FLOW_H
35#define LP_BLD_FLOW_H
36
37
38#include "gallivm/lp_bld.h"
39
40#ifdef __cplusplus
41extern "C" {
42#endif
43
44struct lp_type;
45
46
47/**
48 * Early exit. Useful to skip to the end of a function or block when
49 * the execution mask becomes zero or when there is an error condition.
50 */
51struct lp_build_skip_context
52{
53   struct gallivm_state *gallivm;
54
55   /** Block to skip to */
56   LLVMBasicBlockRef block;
57};
58
59void
60lp_build_flow_skip_begin(struct lp_build_skip_context *ctx,
61                         struct gallivm_state *gallivm);
62
63void
64lp_build_flow_skip_cond_break(struct lp_build_skip_context *ctx,
65                              LLVMValueRef cond);
66
67void
68lp_build_flow_skip_end(struct lp_build_skip_context *ctx);
69
70
71struct lp_build_mask_context
72{
73   struct lp_build_skip_context skip;
74
75   LLVMTypeRef reg_type;
76   LLVMTypeRef var_type;
77   /* 'var' is a pointer (alloca) pointing to 'var_type' */
78   LLVMValueRef var;
79};
80
81
82void
83lp_build_mask_begin(struct lp_build_mask_context *mask,
84                    struct gallivm_state *gallivm,
85                    struct lp_type type,
86                    LLVMValueRef value);
87
88LLVMValueRef
89lp_build_mask_value(struct lp_build_mask_context *mask);
90
91/**
92 * Bitwise AND the mask with the given value, if a previous mask was set.
93 */
94void
95lp_build_mask_update(struct lp_build_mask_context *mask,
96                     LLVMValueRef value);
97
98void
99lp_build_mask_force(struct lp_build_mask_context *mask,
100                    LLVMValueRef value);
101
102void
103lp_build_mask_check(struct lp_build_mask_context *mask);
104
105LLVMValueRef
106lp_build_mask_end(struct lp_build_mask_context *mask);
107
108
109/**
110 * LLVM's IR doesn't represent for-loops directly. Furthermore it
111 * requires creating code blocks, branches, phi variables, so it
112 * requires a fair amount of code.
113 *
114 * @sa http://www.llvm.org/docs/tutorial/LangImpl5.html#for
115 */
116struct lp_build_loop_state
117{
118   LLVMBasicBlockRef block;
119   LLVMValueRef counter_var;
120   LLVMValueRef counter;
121   LLVMTypeRef counter_type;
122   struct gallivm_state *gallivm;
123};
124
125
126void
127lp_build_loop_begin(struct lp_build_loop_state *state,
128                    struct gallivm_state *gallivm,
129                    LLVMValueRef start);
130
131void
132lp_build_loop_end(struct lp_build_loop_state *state,
133                  LLVMValueRef end,
134                  LLVMValueRef step);
135
136void
137lp_build_loop_force_set_counter(struct lp_build_loop_state *state,
138                                LLVMValueRef end);
139
140void
141lp_build_loop_force_reload_counter(struct lp_build_loop_state *state);
142void
143lp_build_loop_end_cond(struct lp_build_loop_state *state,
144                       LLVMValueRef end,
145                       LLVMValueRef step,
146                       LLVMIntPredicate cond);
147
148
149/**
150 * Implementation of simple C-style for loops
151 */
152struct lp_build_for_loop_state
153{
154   LLVMBasicBlockRef begin;
155   LLVMBasicBlockRef body;
156   LLVMBasicBlockRef exit;
157   LLVMValueRef counter_var;
158   LLVMValueRef counter;
159   LLVMTypeRef counter_type;
160   LLVMValueRef step;
161   LLVMIntPredicate cond;
162   LLVMValueRef end;
163   struct gallivm_state *gallivm;
164};
165
166void
167lp_build_for_loop_begin(struct lp_build_for_loop_state *state,
168                        struct gallivm_state *gallivm,
169                        LLVMValueRef start,
170                        LLVMIntPredicate llvm_cond,
171                        LLVMValueRef end,
172                        LLVMValueRef step);
173
174void
175lp_build_for_loop_end(struct lp_build_for_loop_state *state);
176
177
178/**
179 * if/else/endif.
180 */
181struct lp_build_if_state
182{
183   struct gallivm_state *gallivm;
184   LLVMValueRef condition;
185   LLVMBasicBlockRef entry_block;
186   LLVMBasicBlockRef true_block;
187   LLVMBasicBlockRef false_block;
188   LLVMBasicBlockRef merge_block;
189};
190
191
192void
193lp_build_if(struct lp_build_if_state *ctx,
194            struct gallivm_state *gallivm,
195            LLVMValueRef condition);
196
197void
198lp_build_else(struct lp_build_if_state *ctx);
199
200void
201lp_build_endif(struct lp_build_if_state *ctx);
202
203LLVMBasicBlockRef
204lp_build_insert_new_block(struct gallivm_state *gallivm, const char *name);
205
206LLVMValueRef
207lp_build_alloca(struct gallivm_state *gallivm,
208                LLVMTypeRef type,
209                const char *name);
210
211LLVMValueRef
212lp_build_alloca_undef(struct gallivm_state *gallivm,
213                      LLVMTypeRef type,
214                      const char *name);
215
216LLVMValueRef
217lp_build_array_alloca(struct gallivm_state *gallivm,
218                      LLVMTypeRef type,
219                      LLVMValueRef count,
220                      const char *name);
221
222#ifdef __cplusplus
223}
224#endif
225
226#endif /* !LP_BLD_FLOW_H */
227