]>
Commit | Line | Data |
---|---|---|
826c9564 | 1 | /* Register note definitions. |
8d9254fc | 2 | Copyright (C) 2004-2020 Free Software Foundation, Inc. |
826c9564 ZW |
3 | |
4 | This file is part of GCC. | |
5 | ||
6 | GCC is free software; you can redistribute it and/or modify it under | |
7 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 8 | Software Foundation; either version 3, or (at your option) any later |
826c9564 ZW |
9 | version. |
10 | ||
11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
826c9564 ZW |
19 | |
20 | /* This file defines all the codes that may appear on individual | |
e5af9ddd RS |
21 | EXPR_LIST, INSN_LIST and INT_LIST rtxes in the REG_NOTES chain of an insn. |
22 | The codes are stored in the mode field of the rtx. Source files | |
aade772d JJ |
23 | define DEF_REG_NOTE appropriately before including this file. |
24 | ||
25 | CFA related notes meant for RTX_FRAME_RELATED_P instructions | |
26 | should be declared with REG_CFA_NOTE macro instead of REG_NOTE. */ | |
826c9564 ZW |
27 | |
28 | /* Shorthand. */ | |
29 | #define REG_NOTE(NAME) DEF_REG_NOTE (REG_##NAME) | |
aade772d JJ |
30 | #ifndef REG_CFA_NOTE |
31 | # define REG_CFA_NOTE(NAME) REG_NOTE (NAME) | |
32 | #endif | |
826c9564 | 33 | |
b198261f MK |
34 | /* REG_DEP_TRUE is used in scheduler dependencies lists to represent a |
35 | read-after-write dependency (i.e. a true data dependency). This is | |
36 | here, not grouped with REG_DEP_ANTI and REG_DEP_OUTPUT, because some | |
37 | passes use a literal 0 for it. */ | |
52c5701b ZW |
38 | REG_NOTE (DEP_TRUE) |
39 | ||
826c9564 ZW |
40 | /* The value in REG dies in this insn (i.e., it is not needed past |
41 | this insn). If REG is set in this insn, the REG_DEAD note may, | |
42 | but need not, be omitted. */ | |
43 | REG_NOTE (DEAD) | |
44 | ||
45 | /* The REG is autoincremented or autodecremented in this insn. */ | |
46 | REG_NOTE (INC) | |
47 | ||
48 | /* Describes the insn as a whole; it says that the insn sets a | |
49 | register to a constant value or to be equivalent to a memory | |
50 | address. If the register is spilled to the stack then the constant | |
51 | value should be substituted for it. The contents of the REG_EQUIV | |
52 | is the constant value or memory address, which may be different | |
53 | from the source of the SET although it has the same value. A | |
54 | REG_EQUIV note may also appear on an insn which copies a register | |
55 | parameter to a pseudo-register, if there is a memory address which | |
56 | could be used to hold that pseudo-register throughout the function. */ | |
57 | REG_NOTE (EQUIV) | |
58 | ||
59 | /* Like REG_EQUIV except that the destination is only momentarily | |
60 | equal to the specified rtx. Therefore, it cannot be used for | |
4a8cae83 | 61 | substitution; but it can be used for cse. */ |
826c9564 ZW |
62 | REG_NOTE (EQUAL) |
63 | ||
826c9564 ZW |
64 | /* The register is always nonnegative during the containing loop. |
65 | This is used in branches so that decrement and branch instructions | |
66 | terminating on zero can be matched. There must be an insn pattern | |
67 | in the md file named `decrement_and_branch_until_zero' or else this | |
68 | will never be added to any instructions. */ | |
69 | REG_NOTE (NONNEG) | |
70 | ||
826c9564 ZW |
71 | /* Identifies a register set in this insn and never used. */ |
72 | REG_NOTE (UNUSED) | |
73 | ||
74 | /* REG_CC_SETTER and REG_CC_USER link a pair of insns that set and use | |
75 | CC0, respectively. Normally, these are required to be consecutive | |
76 | insns, but we permit putting a cc0-setting insn in the delay slot | |
77 | of a branch as long as only one copy of the insn exists. In that | |
78 | case, these notes point from one to the other to allow code | |
79 | generation to determine what any require information and to | |
80 | properly update CC_STATUS. These notes are INSN_LISTs. */ | |
81 | REG_NOTE (CC_SETTER) | |
82 | REG_NOTE (CC_USER) | |
83 | ||
cf7c4aa6 HPN |
84 | /* Points to a CODE_LABEL. Used by JUMP_INSNs to say that the CODE_LABEL |
85 | contained in the REG_LABEL_TARGET note is a possible jump target of | |
86 | this insn. This note is an INSN_LIST. */ | |
87 | REG_NOTE (LABEL_TARGET) | |
88 | ||
89 | /* Points to a CODE_LABEL. Used by any insn to say that the CODE_LABEL | |
90 | contained in the REG_LABEL_OPERAND note is used by the insn, but as an | |
91 | operand, not as a jump target (though it may indirectly be a jump | |
92 | target for a later jump insn). This note is an INSN_LIST. */ | |
93 | REG_NOTE (LABEL_OPERAND) | |
826c9564 | 94 | |
b198261f MK |
95 | /* REG_DEP_OUTPUT and REG_DEP_ANTI are used in scheduler dependencies lists |
96 | to represent write-after-write and write-after-read dependencies | |
97 | respectively. */ | |
826c9564 | 98 | REG_NOTE (DEP_OUTPUT) |
ddbd5439 | 99 | REG_NOTE (DEP_ANTI) |
e2724e63 | 100 | REG_NOTE (DEP_CONTROL) |
826c9564 | 101 | |
5fa396ad | 102 | /* REG_BR_PROB is attached to JUMP_INSNs. It has an |
e5af9ddd | 103 | integer value (in an INT_LIST). For jumps, it is the probability |
5fa396ad JH |
104 | that this is a taken branch. The integer represents a value of |
105 | profile_probability type. Use to_reg_br_prob_note and from_reg_br_prob_note | |
106 | to extract the actual value. */ | |
826c9564 ZW |
107 | REG_NOTE (BR_PROB) |
108 | ||
826c9564 ZW |
109 | /* Attached to a call insn; indicates that the call is malloc-like and |
110 | that the pointer returned cannot alias anything else. */ | |
111 | REG_NOTE (NOALIAS) | |
112 | ||
5fa396ad | 113 | /* REG_BR_PRED is attached to JUMP_INSNs. It contains |
826c9564 ZW |
114 | CONCAT of two integer value. First specifies the branch predictor |
115 | that added the note, second specifies the predicted hitrate of | |
5fa396ad | 116 | branch in a fixed point arithmetic based on REG_BR_PROB_BASE. */ |
826c9564 ZW |
117 | REG_NOTE (BR_PRED) |
118 | ||
119 | /* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex | |
120 | for DWARF to interpret what they imply. The attached rtx is used | |
121 | instead of intuition. */ | |
aade772d | 122 | REG_CFA_NOTE (FRAME_RELATED_EXPR) |
826c9564 | 123 | |
cd9c1ca8 RH |
124 | /* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex |
125 | for FRAME_RELATED_EXPR intuition. The insn's first pattern must be | |
126 | a SET, and the destination must be the CFA register. The attached | |
127 | rtx is an expression that defines the CFA. In the simplest case, the | |
128 | rtx could be just the stack_pointer_rtx; more common would be a PLUS | |
129 | with a base register and a constant offset. In the most complicated | |
130 | cases, this will result in a DW_CFA_def_cfa_expression with the rtx | |
131 | expression rendered in a dwarf location expression. */ | |
aade772d | 132 | REG_CFA_NOTE (CFA_DEF_CFA) |
cd9c1ca8 RH |
133 | |
134 | /* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex | |
135 | for FRAME_RELATED_EXPR intuition. This note adjusts the expression | |
136 | from which the CFA is computed. The attached rtx defines a new CFA | |
137 | expression, relative to the old CFA expression. This rtx must be of | |
138 | the form (SET new-cfa-reg (PLUS old-cfa-reg const_int)). If the note | |
139 | rtx is NULL, we use the first SET of the insn. */ | |
aade772d | 140 | REG_CFA_NOTE (CFA_ADJUST_CFA) |
cd9c1ca8 RH |
141 | |
142 | /* Similar to FRAME_RELATED_EXPR, with the additional information that | |
143 | this is a save to memory, i.e. will result in DW_CFA_offset or the | |
144 | like. The pattern or the insn should be a simple store relative to | |
145 | the CFA. */ | |
aade772d | 146 | REG_CFA_NOTE (CFA_OFFSET) |
cd9c1ca8 RH |
147 | |
148 | /* Similar to FRAME_RELATED_EXPR, with the additional information that this | |
149 | is a save to a register, i.e. will result in DW_CFA_register. The insn | |
150 | or the pattern should be simple reg-reg move. */ | |
aade772d | 151 | REG_CFA_NOTE (CFA_REGISTER) |
cd9c1ca8 | 152 | |
c9f4c451 RH |
153 | /* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex |
154 | for FRAME_RELATED_EXPR intuition. This is a save to memory, i.e. will | |
155 | result in a DW_CFA_expression. The pattern or the insn should be a | |
156 | store of a register to an arbitrary (non-validated) memory address. */ | |
aade772d | 157 | REG_CFA_NOTE (CFA_EXPRESSION) |
c9f4c451 | 158 | |
ac5b3eff JW |
159 | /* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex |
160 | for FRAME_RELATED_EXPR intuition. The DWARF expression computes the value of | |
161 | the given register. */ | |
aade772d | 162 | REG_CFA_NOTE (CFA_VAL_EXPRESSION) |
ac5b3eff | 163 | |
cd9c1ca8 RH |
164 | /* Attached to insns that are RTX_FRAME_RELATED_P, with the information |
165 | that this is a restore operation, i.e. will result in DW_CFA_restore | |
166 | or the like. Either the attached rtx, or the destination of the insn's | |
167 | first pattern is the register to be restored. */ | |
aade772d | 168 | REG_CFA_NOTE (CFA_RESTORE) |
cd9c1ca8 | 169 | |
ef284364 | 170 | /* Attached to insns that are RTX_FRAME_RELATED_P, marks insn that sets |
23f39b37 JJ |
171 | vDRAP from DRAP. If vDRAP is a register, vdrap_reg is initalized |
172 | to the argument, if it is a MEM, it is ignored. */ | |
aade772d | 173 | REG_CFA_NOTE (CFA_SET_VDRAP) |
23f39b37 | 174 | |
ef284364 | 175 | /* Attached to insns that are RTX_FRAME_RELATED_P, indicating a window |
78a8eb4e RH |
176 | save operation, i.e. will result in a DW_CFA_GNU_window_save. |
177 | The argument is ignored. */ | |
aade772d | 178 | REG_CFA_NOTE (CFA_WINDOW_SAVE) |
78a8eb4e | 179 | |
ef284364 RH |
180 | /* Attached to insns that are RTX_FRAME_RELATED_P, marks the insn as |
181 | requiring that all queued information should be flushed *before* insn, | |
182 | regardless of what is visible in the rtl. The argument is ignored. | |
183 | This is normally used for a call instruction which is not exposed to | |
184 | the rest of the compiler as a CALL_INSN. */ | |
aade772d | 185 | REG_CFA_NOTE (CFA_FLUSH_QUEUE) |
ef284364 | 186 | |
27169e45 JW |
187 | /* Attached to insns that are RTX_FRAME_RELATED_P, toggling the mangling status |
188 | of return address. Currently it's only used by AArch64. The argument is | |
189 | ignored. */ | |
aade772d | 190 | REG_CFA_NOTE (CFA_TOGGLE_RA_MANGLE) |
27169e45 | 191 | |
826c9564 ZW |
192 | /* Indicates what exception region an INSN belongs in. This is used |
193 | to indicate what region to which a call may throw. REGION 0 | |
194 | indicates that a call cannot throw at all. REGION -1 indicates | |
195 | that it cannot throw, nor will it execute a non-local goto. */ | |
196 | REG_NOTE (EH_REGION) | |
197 | ||
198 | /* Used by haifa-sched to save NOTE_INSN notes across scheduling. */ | |
199 | REG_NOTE (SAVE_NOTE) | |
200 | ||
826c9564 ZW |
201 | /* Indicates that a call does not return. */ |
202 | REG_NOTE (NORETURN) | |
203 | ||
204 | /* Indicates that an indirect jump is a non-local goto instead of a | |
205 | computed goto. */ | |
206 | REG_NOTE (NON_LOCAL_GOTO) | |
207 | ||
826c9564 ZW |
208 | /* This kind of note is generated at each to `setjmp', and similar |
209 | functions that can return twice. */ | |
210 | REG_NOTE (SETJMP) | |
9a08d230 | 211 | |
0a35513e AH |
212 | /* This kind of note is generated at each transactional memory |
213 | builtin, to indicate we need to generate transaction restart | |
214 | edges for this insn. */ | |
215 | REG_NOTE (TM) | |
216 | ||
9a08d230 RH |
217 | /* Indicates the cumulative offset of the stack pointer accounting |
218 | for pushed arguments. This will only be generated when | |
219 | ACCUMULATE_OUTGOING_ARGS is false. */ | |
220 | REG_NOTE (ARGS_SIZE) | |
e384e6b5 BS |
221 | |
222 | /* Used for communication between IRA and caller-save.c, indicates | |
223 | that the return value of a call can be used to reinitialize a | |
224 | pseudo reg. */ | |
225 | REG_NOTE (RETURNED) | |
4f660b15 | 226 | |
ac9c032e JL |
227 | /* Indicates the instruction is a stack check probe that should not |
228 | be combined with other stack adjustments. */ | |
229 | REG_NOTE (STACK_CHECK) | |
230 | ||
4f660b15 RO |
231 | /* Used to mark a call with the function decl called by the call. |
232 | The decl might not be available in the call due to splitting of the call | |
233 | insn. This note is a SYMBOL_REF. */ | |
234 | REG_NOTE (CALL_DECL) | |
5c5f0b65 IT |
235 | |
236 | /* Indicate that a call should not be verified for control-flow consistency. | |
237 | The target address of the call is assumed as a valid address and no check | |
238 | to validate a branch to the target address is needed. The call is marked | |
239 | when a called function has a 'notrack' attribute. This note is used by the | |
240 | compiler when the option -fcf-protection=branch is specified. */ | |
241 | REG_NOTE (CALL_NOCF_CHECK) | |
00b94487 JJ |
242 | |
243 | /* The values passed to callee, for debuginfo purposes. */ | |
244 | REG_NOTE (CALL_ARG_LOCATION) |