xref: /dflybsd-src/contrib/gcc-4.7/gcc/reg-notes.def (revision 04febcfb30580676d3e95f58a16c5137ee478b32)
1*e4b17023SJohn Marino/* Register note definitions.
2*e4b17023SJohn Marino   Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010
3*e4b17023SJohn Marino   Free Software Foundation, Inc.
4*e4b17023SJohn Marino
5*e4b17023SJohn MarinoThis file is part of GCC.
6*e4b17023SJohn Marino
7*e4b17023SJohn MarinoGCC is free software; you can redistribute it and/or modify it under
8*e4b17023SJohn Marinothe terms of the GNU General Public License as published by the Free
9*e4b17023SJohn MarinoSoftware Foundation; either version 3, or (at your option) any later
10*e4b17023SJohn Marinoversion.
11*e4b17023SJohn Marino
12*e4b17023SJohn MarinoGCC is distributed in the hope that it will be useful, but WITHOUT ANY
13*e4b17023SJohn MarinoWARRANTY; without even the implied warranty of MERCHANTABILITY or
14*e4b17023SJohn MarinoFITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
15*e4b17023SJohn Marinofor more details.
16*e4b17023SJohn Marino
17*e4b17023SJohn MarinoYou should have received a copy of the GNU General Public License
18*e4b17023SJohn Marinoalong with GCC; see the file COPYING3.  If not see
19*e4b17023SJohn Marino<http://www.gnu.org/licenses/>.  */
20*e4b17023SJohn Marino
21*e4b17023SJohn Marino/* This file defines all the codes that may appear on individual
22*e4b17023SJohn Marino   EXPR_LIST rtxes in the REG_NOTES chain of an insn.  The codes are
23*e4b17023SJohn Marino   stored in the mode field of the EXPR_LIST.  Source files define
24*e4b17023SJohn Marino   DEF_REG_NOTE appropriately before including this file.  */
25*e4b17023SJohn Marino
26*e4b17023SJohn Marino/* Shorthand.  */
27*e4b17023SJohn Marino#define REG_NOTE(NAME) DEF_REG_NOTE (REG_##NAME)
28*e4b17023SJohn Marino
29*e4b17023SJohn Marino/* REG_DEP_TRUE is used in scheduler dependencies lists to represent a
30*e4b17023SJohn Marino   read-after-write dependency (i.e. a true data dependency).  This is
31*e4b17023SJohn Marino   here, not grouped with REG_DEP_ANTI and REG_DEP_OUTPUT, because some
32*e4b17023SJohn Marino   passes use a literal 0 for it.  */
33*e4b17023SJohn MarinoREG_NOTE (DEP_TRUE)
34*e4b17023SJohn Marino
35*e4b17023SJohn Marino/* The value in REG dies in this insn (i.e., it is not needed past
36*e4b17023SJohn Marino   this insn).  If REG is set in this insn, the REG_DEAD note may,
37*e4b17023SJohn Marino   but need not, be omitted.  */
38*e4b17023SJohn MarinoREG_NOTE (DEAD)
39*e4b17023SJohn Marino
40*e4b17023SJohn Marino/* The REG is autoincremented or autodecremented in this insn.  */
41*e4b17023SJohn MarinoREG_NOTE (INC)
42*e4b17023SJohn Marino
43*e4b17023SJohn Marino/* Describes the insn as a whole; it says that the insn sets a
44*e4b17023SJohn Marino   register to a constant value or to be equivalent to a memory
45*e4b17023SJohn Marino   address.  If the register is spilled to the stack then the constant
46*e4b17023SJohn Marino   value should be substituted for it.  The contents of the REG_EQUIV
47*e4b17023SJohn Marino   is the constant value or memory address, which may be different
48*e4b17023SJohn Marino   from the source of the SET although it has the same value.  A
49*e4b17023SJohn Marino   REG_EQUIV note may also appear on an insn which copies a register
50*e4b17023SJohn Marino   parameter to a pseudo-register, if there is a memory address which
51*e4b17023SJohn Marino   could be used to hold that pseudo-register throughout the function.  */
52*e4b17023SJohn MarinoREG_NOTE (EQUIV)
53*e4b17023SJohn Marino
54*e4b17023SJohn Marino/* Like REG_EQUIV except that the destination is only momentarily
55*e4b17023SJohn Marino   equal to the specified rtx.  Therefore, it cannot be used for
56*e4b17023SJohn Marino   substitution; but it can be used for cse.  */
57*e4b17023SJohn MarinoREG_NOTE (EQUAL)
58*e4b17023SJohn Marino
59*e4b17023SJohn Marino/* The register is always nonnegative during the containing loop.
60*e4b17023SJohn Marino   This is used in branches so that decrement and branch instructions
61*e4b17023SJohn Marino   terminating on zero can be matched.  There must be an insn pattern
62*e4b17023SJohn Marino   in the md file named `decrement_and_branch_until_zero' or else this
63*e4b17023SJohn Marino   will never be added to any instructions.  */
64*e4b17023SJohn MarinoREG_NOTE (NONNEG)
65*e4b17023SJohn Marino
66*e4b17023SJohn Marino/* Identifies a register set in this insn and never used.  */
67*e4b17023SJohn MarinoREG_NOTE (UNUSED)
68*e4b17023SJohn Marino
69*e4b17023SJohn Marino/* REG_CC_SETTER and REG_CC_USER link a pair of insns that set and use
70*e4b17023SJohn Marino   CC0, respectively.  Normally, these are required to be consecutive
71*e4b17023SJohn Marino   insns, but we permit putting a cc0-setting insn in the delay slot
72*e4b17023SJohn Marino   of a branch as long as only one copy of the insn exists.  In that
73*e4b17023SJohn Marino   case, these notes point from one to the other to allow code
74*e4b17023SJohn Marino   generation to determine what any require information and to
75*e4b17023SJohn Marino   properly update CC_STATUS.  These notes are INSN_LISTs.  */
76*e4b17023SJohn MarinoREG_NOTE (CC_SETTER)
77*e4b17023SJohn MarinoREG_NOTE (CC_USER)
78*e4b17023SJohn Marino
79*e4b17023SJohn Marino/* Points to a CODE_LABEL.  Used by JUMP_INSNs to say that the CODE_LABEL
80*e4b17023SJohn Marino   contained in the REG_LABEL_TARGET note is a possible jump target of
81*e4b17023SJohn Marino   this insn.  This note is an INSN_LIST.  */
82*e4b17023SJohn MarinoREG_NOTE (LABEL_TARGET)
83*e4b17023SJohn Marino
84*e4b17023SJohn Marino/* Points to a CODE_LABEL.  Used by any insn to say that the CODE_LABEL
85*e4b17023SJohn Marino   contained in the REG_LABEL_OPERAND note is used by the insn, but as an
86*e4b17023SJohn Marino   operand, not as a jump target (though it may indirectly be a jump
87*e4b17023SJohn Marino   target for a later jump insn).  This note is an INSN_LIST.  */
88*e4b17023SJohn MarinoREG_NOTE (LABEL_OPERAND)
89*e4b17023SJohn Marino
90*e4b17023SJohn Marino/* REG_DEP_OUTPUT and REG_DEP_ANTI are used in scheduler dependencies lists
91*e4b17023SJohn Marino   to represent write-after-write and write-after-read dependencies
92*e4b17023SJohn Marino   respectively.  */
93*e4b17023SJohn MarinoREG_NOTE (DEP_OUTPUT)
94*e4b17023SJohn MarinoREG_NOTE (DEP_ANTI)
95*e4b17023SJohn MarinoREG_NOTE (DEP_CONTROL)
96*e4b17023SJohn Marino
97*e4b17023SJohn Marino/* REG_BR_PROB is attached to JUMP_INSNs and CALL_INSNs.  It has an
98*e4b17023SJohn Marino   integer value.  For jumps, it is the probability that this is a
99*e4b17023SJohn Marino   taken branch.  For calls, it is the probability that this call
100*e4b17023SJohn Marino   won't return.  */
101*e4b17023SJohn MarinoREG_NOTE (BR_PROB)
102*e4b17023SJohn Marino
103*e4b17023SJohn Marino/* Attached to a call insn; indicates that the call is malloc-like and
104*e4b17023SJohn Marino   that the pointer returned cannot alias anything else.  */
105*e4b17023SJohn MarinoREG_NOTE (NOALIAS)
106*e4b17023SJohn Marino
107*e4b17023SJohn Marino/* REG_BR_PRED is attached to JUMP_INSNs and CALL_INSNSs.  It contains
108*e4b17023SJohn Marino   CONCAT of two integer value.  First specifies the branch predictor
109*e4b17023SJohn Marino   that added the note, second specifies the predicted hitrate of
110*e4b17023SJohn Marino   branch in the same format as REG_BR_PROB note uses.  */
111*e4b17023SJohn MarinoREG_NOTE (BR_PRED)
112*e4b17023SJohn Marino
113*e4b17023SJohn Marino/* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex
114*e4b17023SJohn Marino   for DWARF to interpret what they imply.  The attached rtx is used
115*e4b17023SJohn Marino   instead of intuition.  */
116*e4b17023SJohn MarinoREG_NOTE (FRAME_RELATED_EXPR)
117*e4b17023SJohn Marino
118*e4b17023SJohn Marino/* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex
119*e4b17023SJohn Marino   for FRAME_RELATED_EXPR intuition.  The insn's first pattern must be
120*e4b17023SJohn Marino   a SET, and the destination must be the CFA register.  The attached
121*e4b17023SJohn Marino   rtx is an expression that defines the CFA.  In the simplest case, the
122*e4b17023SJohn Marino   rtx could be just the stack_pointer_rtx; more common would be a PLUS
123*e4b17023SJohn Marino   with a base register and a constant offset.  In the most complicated
124*e4b17023SJohn Marino   cases, this will result in a DW_CFA_def_cfa_expression with the rtx
125*e4b17023SJohn Marino   expression rendered in a dwarf location expression.  */
126*e4b17023SJohn MarinoREG_NOTE (CFA_DEF_CFA)
127*e4b17023SJohn Marino
128*e4b17023SJohn Marino/* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex
129*e4b17023SJohn Marino   for FRAME_RELATED_EXPR intuition.  This note adjusts the expression
130*e4b17023SJohn Marino   from which the CFA is computed.  The attached rtx defines a new CFA
131*e4b17023SJohn Marino   expression, relative to the old CFA expression.  This rtx must be of
132*e4b17023SJohn Marino   the form (SET new-cfa-reg (PLUS old-cfa-reg const_int)).  If the note
133*e4b17023SJohn Marino   rtx is NULL, we use the first SET of the insn.  */
134*e4b17023SJohn MarinoREG_NOTE (CFA_ADJUST_CFA)
135*e4b17023SJohn Marino
136*e4b17023SJohn Marino/* Similar to FRAME_RELATED_EXPR, with the additional information that
137*e4b17023SJohn Marino   this is a save to memory, i.e. will result in DW_CFA_offset or the
138*e4b17023SJohn Marino   like.  The pattern or the insn should be a simple store relative to
139*e4b17023SJohn Marino   the CFA.  */
140*e4b17023SJohn MarinoREG_NOTE (CFA_OFFSET)
141*e4b17023SJohn Marino
142*e4b17023SJohn Marino/* Similar to FRAME_RELATED_EXPR, with the additional information that this
143*e4b17023SJohn Marino   is a save to a register, i.e. will result in DW_CFA_register.  The insn
144*e4b17023SJohn Marino   or the pattern should be simple reg-reg move.  */
145*e4b17023SJohn MarinoREG_NOTE (CFA_REGISTER)
146*e4b17023SJohn Marino
147*e4b17023SJohn Marino/* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex
148*e4b17023SJohn Marino   for FRAME_RELATED_EXPR intuition.  This is a save to memory, i.e. will
149*e4b17023SJohn Marino   result in a DW_CFA_expression.  The pattern or the insn should be a
150*e4b17023SJohn Marino   store of a register to an arbitrary (non-validated) memory address.  */
151*e4b17023SJohn MarinoREG_NOTE (CFA_EXPRESSION)
152*e4b17023SJohn Marino
153*e4b17023SJohn Marino/* Attached to insns that are RTX_FRAME_RELATED_P, with the information
154*e4b17023SJohn Marino   that this is a restore operation, i.e. will result in DW_CFA_restore
155*e4b17023SJohn Marino   or the like.  Either the attached rtx, or the destination of the insn's
156*e4b17023SJohn Marino   first pattern is the register to be restored.  */
157*e4b17023SJohn MarinoREG_NOTE (CFA_RESTORE)
158*e4b17023SJohn Marino
159*e4b17023SJohn Marino/* Attached to insns that are RTX_FRAME_RELATED_P, marks insn that sets
160*e4b17023SJohn Marino   vDRAP from DRAP.  If vDRAP is a register, vdrap_reg is initalized
161*e4b17023SJohn Marino   to the argument, if it is a MEM, it is ignored.  */
162*e4b17023SJohn MarinoREG_NOTE (CFA_SET_VDRAP)
163*e4b17023SJohn Marino
164*e4b17023SJohn Marino/* Attached to insns that are RTX_FRAME_RELATED_P, indicating a window
165*e4b17023SJohn Marino   save operation, i.e. will result in a DW_CFA_GNU_window_save.
166*e4b17023SJohn Marino   The argument is ignored.  */
167*e4b17023SJohn MarinoREG_NOTE (CFA_WINDOW_SAVE)
168*e4b17023SJohn Marino
169*e4b17023SJohn Marino/* Attached to insns that are RTX_FRAME_RELATED_P, marks the insn as
170*e4b17023SJohn Marino   requiring that all queued information should be flushed *before* insn,
171*e4b17023SJohn Marino   regardless of what is visible in the rtl.  The argument is ignored.
172*e4b17023SJohn Marino   This is normally used for a call instruction which is not exposed to
173*e4b17023SJohn Marino   the rest of the compiler as a CALL_INSN.  */
174*e4b17023SJohn MarinoREG_NOTE (CFA_FLUSH_QUEUE)
175*e4b17023SJohn Marino
176*e4b17023SJohn Marino/* Indicates that REG holds the exception context for the function.
177*e4b17023SJohn Marino   This context is shared by inline functions, so the code to acquire
178*e4b17023SJohn Marino   the real exception context is delayed until after inlining.  */
179*e4b17023SJohn MarinoREG_NOTE (EH_CONTEXT)
180*e4b17023SJohn Marino
181*e4b17023SJohn Marino/* Indicates what exception region an INSN belongs in.  This is used
182*e4b17023SJohn Marino   to indicate what region to which a call may throw.  REGION 0
183*e4b17023SJohn Marino   indicates that a call cannot throw at all.  REGION -1 indicates
184*e4b17023SJohn Marino   that it cannot throw, nor will it execute a non-local goto.  */
185*e4b17023SJohn MarinoREG_NOTE (EH_REGION)
186*e4b17023SJohn Marino
187*e4b17023SJohn Marino/* Used by haifa-sched to save NOTE_INSN notes across scheduling.  */
188*e4b17023SJohn MarinoREG_NOTE (SAVE_NOTE)
189*e4b17023SJohn Marino
190*e4b17023SJohn Marino/* Indicates that a call does not return.  */
191*e4b17023SJohn MarinoREG_NOTE (NORETURN)
192*e4b17023SJohn Marino
193*e4b17023SJohn Marino/* Indicates that an indirect jump is a non-local goto instead of a
194*e4b17023SJohn Marino   computed goto.  */
195*e4b17023SJohn MarinoREG_NOTE (NON_LOCAL_GOTO)
196*e4b17023SJohn Marino
197*e4b17023SJohn Marino/* Indicates that a jump crosses between hot and cold sections in a
198*e4b17023SJohn Marino   (partitioned) assembly or .o file, and therefore should not be
199*e4b17023SJohn Marino   reduced to a simpler jump by optimizations.  */
200*e4b17023SJohn MarinoREG_NOTE (CROSSING_JUMP)
201*e4b17023SJohn Marino
202*e4b17023SJohn Marino/* This kind of note is generated at each to `setjmp', and similar
203*e4b17023SJohn Marino   functions that can return twice.  */
204*e4b17023SJohn MarinoREG_NOTE (SETJMP)
205*e4b17023SJohn Marino
206*e4b17023SJohn Marino/* This kind of note is generated at each transactional memory
207*e4b17023SJohn Marino   builtin, to indicate we need to generate transaction restart
208*e4b17023SJohn Marino   edges for this insn.  */
209*e4b17023SJohn MarinoREG_NOTE (TM)
210*e4b17023SJohn Marino
211*e4b17023SJohn Marino/* Indicates the cumulative offset of the stack pointer accounting
212*e4b17023SJohn Marino   for pushed arguments.  This will only be generated when
213*e4b17023SJohn Marino   ACCUMULATE_OUTGOING_ARGS is false.  */
214*e4b17023SJohn MarinoREG_NOTE (ARGS_SIZE)
215