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
77   LLVMValueRef var;
78};
79
80
81void
82lp_build_mask_begin(struct lp_build_mask_context *mask,
83                    struct gallivm_state *gallivm,
84                    struct lp_type type,
85                    LLVMValueRef value);
86
87LLVMValueRef
88lp_build_mask_value(struct lp_build_mask_context *mask);
89
90/**
91 * Bitwise AND the mask with the given value, if a previous mask was set.
92 */
93void
94lp_build_mask_update(struct lp_build_mask_context *mask,
95                     LLVMValueRef value);
96
97void
98lp_build_mask_force(struct lp_build_mask_context *mask,
99                    LLVMValueRef value);
100
101void
102lp_build_mask_check(struct lp_build_mask_context *mask);
103
104LLVMValueRef
105lp_build_mask_end(struct lp_build_mask_context *mask);
106
107
108/**
109 * LLVM's IR doesn't represent for-loops directly. Furthermore it
110 * it requires creating code blocks, branches, phi variables, so it
111 * requires a fair amount of code.
112 *
113 * @sa http://www.llvm.org/docs/tutorial/LangImpl5.html#for
114 */
115struct lp_build_loop_state
116{
117   LLVMBasicBlockRef block;
118   LLVMValueRef counter_var;
119   LLVMValueRef counter;
120   struct gallivm_state *gallivm;
121};
122
123
124void
125lp_build_loop_begin(struct lp_build_loop_state *state,
126                    struct gallivm_state *gallivm,
127                    LLVMValueRef start);
128
129void
130lp_build_loop_end(struct lp_build_loop_state *state,
131                  LLVMValueRef end,
132                  LLVMValueRef step);
133
134void
135lp_build_loop_force_set_counter(struct lp_build_loop_state *state,
136                                LLVMValueRef end);
137
138void
139lp_build_loop_force_reload_counter(struct lp_build_loop_state *state);
140void
141lp_build_loop_end_cond(struct lp_build_loop_state *state,
142                       LLVMValueRef end,
143                       LLVMValueRef step,
144                       LLVMIntPredicate cond);
145
146
147/**
148 * Implementation of simple C-style for loops
149 */
150struct lp_build_for_loop_state
151{
152   LLVMBasicBlockRef begin;
153   LLVMBasicBlockRef body;
154   LLVMBasicBlockRef exit;
155   LLVMValueRef counter_var;
156   LLVMValueRef counter;
157   LLVMValueRef step;
158   LLVMIntPredicate cond;
159   LLVMValueRef end;
160   struct gallivm_state *gallivm;
161};
162
163void
164lp_build_for_loop_begin(struct lp_build_for_loop_state *state,
165                        struct gallivm_state *gallivm,
166                        LLVMValueRef start,
167                        LLVMIntPredicate llvm_cond,
168                        LLVMValueRef end,
169                        LLVMValueRef step);
170
171void
172lp_build_for_loop_end(struct lp_build_for_loop_state *state);
173
174
175/**
176 * if/else/endif.
177 */
178struct lp_build_if_state
179{
180   struct gallivm_state *gallivm;
181   LLVMValueRef condition;
182   LLVMBasicBlockRef entry_block;
183   LLVMBasicBlockRef true_block;
184   LLVMBasicBlockRef false_block;
185   LLVMBasicBlockRef merge_block;
186};
187
188
189void
190lp_build_if(struct lp_build_if_state *ctx,
191            struct gallivm_state *gallivm,
192            LLVMValueRef condition);
193
194void
195lp_build_else(struct lp_build_if_state *ctx);
196
197void
198lp_build_endif(struct lp_build_if_state *ctx);
199
200LLVMBasicBlockRef
201lp_build_insert_new_block(struct gallivm_state *gallivm, const char *name);
202
203LLVMValueRef
204lp_build_alloca(struct gallivm_state *gallivm,
205                LLVMTypeRef type,
206                const char *name);
207
208LLVMValueRef
209lp_build_alloca_undef(struct gallivm_state *gallivm,
210                      LLVMTypeRef type,
211                      const char *name);
212
213LLVMValueRef
214lp_build_array_alloca(struct gallivm_state *gallivm,
215                      LLVMTypeRef type,
216                      LLVMValueRef count,
217                      const char *name);
218
219#ifdef __cplusplus
220}
221#endif
222
223#endif /* !LP_BLD_FLOW_H */
224