166 lines
6.8 KiB
Modula-2
166 lines
6.8 KiB
Modula-2
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/* Register note definitions.
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Copyright (C) 2004, 2005 Free Software Foundation, Inc.
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This file is part of GCC.
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GCC is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free
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Software Foundation; either version 2, or (at your option) any later
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version.
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GCC is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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for more details.
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You should have received a copy of the GNU General Public License
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along with GCC; see the file COPYING. If not, write to the Free
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Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301, USA. */
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/* This file defines all the codes that may appear on individual
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EXPR_LIST rtxes in the REG_NOTES chain of an insn. The codes are
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stored in the mode field of the EXPR_LIST. Source files define
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DEF_REG_NOTE appropriately before including this file. */
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/* Shorthand. */
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#define REG_NOTE(NAME) DEF_REG_NOTE (REG_##NAME)
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/* REG_DEP_TRUE is used in LOG_LINKS to represent a read-after-write
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dependency (i.e. a true data dependency). This is here, not
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grouped with REG_DEP_ANTI and REG_DEP_OUTPUT, because some passes
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use a literal 0 for it. */
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REG_NOTE (DEP_TRUE)
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/* The value in REG dies in this insn (i.e., it is not needed past
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this insn). If REG is set in this insn, the REG_DEAD note may,
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but need not, be omitted. */
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REG_NOTE (DEAD)
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/* The REG is autoincremented or autodecremented in this insn. */
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REG_NOTE (INC)
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/* Describes the insn as a whole; it says that the insn sets a
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register to a constant value or to be equivalent to a memory
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address. If the register is spilled to the stack then the constant
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value should be substituted for it. The contents of the REG_EQUIV
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is the constant value or memory address, which may be different
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from the source of the SET although it has the same value. A
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REG_EQUIV note may also appear on an insn which copies a register
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parameter to a pseudo-register, if there is a memory address which
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could be used to hold that pseudo-register throughout the function. */
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REG_NOTE (EQUIV)
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/* Like REG_EQUIV except that the destination is only momentarily
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equal to the specified rtx. Therefore, it cannot be used for
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substitution; but it can be used for cse. */
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REG_NOTE (EQUAL)
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/* This insn copies the return-value of a library call out of the hard
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reg for return values. This note is actually an INSN_LIST and it
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points to the first insn involved in setting up arguments for the
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call. flow.c uses this to delete the entire library call when its
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result is dead. */
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REG_NOTE (RETVAL)
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/* The inverse of REG_RETVAL: it goes on the first insn of the library
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call and points at the one that has the REG_RETVAL. This note is
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also an INSN_LIST. */
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REG_NOTE (LIBCALL)
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/* The register is always nonnegative during the containing loop.
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This is used in branches so that decrement and branch instructions
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terminating on zero can be matched. There must be an insn pattern
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in the md file named `decrement_and_branch_until_zero' or else this
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will never be added to any instructions. */
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REG_NOTE (NONNEG)
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/* There is no conflict *after this insn* between the register in the
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note and the destination of this insn. */
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REG_NOTE (NO_CONFLICT)
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/* Identifies a register set in this insn and never used. */
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REG_NOTE (UNUSED)
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/* REG_CC_SETTER and REG_CC_USER link a pair of insns that set and use
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CC0, respectively. Normally, these are required to be consecutive
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insns, but we permit putting a cc0-setting insn in the delay slot
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of a branch as long as only one copy of the insn exists. In that
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case, these notes point from one to the other to allow code
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generation to determine what any require information and to
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properly update CC_STATUS. These notes are INSN_LISTs. */
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REG_NOTE (CC_SETTER)
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REG_NOTE (CC_USER)
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/* Points to a CODE_LABEL. Used by non-JUMP_INSNs to say that the
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CODE_LABEL contained in the REG_LABEL note is used by the insn.
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This note is an INSN_LIST. */
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REG_NOTE (LABEL)
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/* REG_DEP_ANTI and REG_DEP_OUTPUT are used in LOG_LINKS to represent
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write-after-read and write-after-write dependencies respectively. */
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REG_NOTE (DEP_OUTPUT)
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REG_NOTE (DEP_ANTI)
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/* REG_BR_PROB is attached to JUMP_INSNs and CALL_INSNs. It has an
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integer value. For jumps, it is the probability that this is a
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taken branch. For calls, it is the probability that this call
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won't return. */
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REG_NOTE (BR_PROB)
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/* REG_VALUE_PROFILE is attached when the profile is read in to an
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insn before that the code to profile the value is inserted. It
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contains the results of profiling. */
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REG_NOTE (VALUE_PROFILE)
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/* Attached to a call insn; indicates that the call is malloc-like and
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that the pointer returned cannot alias anything else. */
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REG_NOTE (NOALIAS)
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/* REG_BR_PRED is attached to JUMP_INSNs and CALL_INSNSs. It contains
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CONCAT of two integer value. First specifies the branch predictor
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that added the note, second specifies the predicted hitrate of
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branch in the same format as REG_BR_PROB note uses. */
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REG_NOTE (BR_PRED)
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/* Attached to insns that are RTX_FRAME_RELATED_P, but are too complex
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for DWARF to interpret what they imply. The attached rtx is used
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instead of intuition. */
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REG_NOTE (FRAME_RELATED_EXPR)
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/* Indicates that REG holds the exception context for the function.
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This context is shared by inline functions, so the code to acquire
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the real exception context is delayed until after inlining. */
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REG_NOTE (EH_CONTEXT)
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/* Indicates what exception region an INSN belongs in. This is used
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to indicate what region to which a call may throw. REGION 0
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indicates that a call cannot throw at all. REGION -1 indicates
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that it cannot throw, nor will it execute a non-local goto. */
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REG_NOTE (EH_REGION)
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/* Used by haifa-sched to save NOTE_INSN notes across scheduling. */
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REG_NOTE (SAVE_NOTE)
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/* Indicates that this insn (which is part of the prologue) computes a
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value which might not be used later, and if so it's OK to delete
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the insn. Normally, deleting any insn in the prologue is an error.
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At present the parameter is unused and set to (const_int 0). */
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REG_NOTE (MAYBE_DEAD)
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/* Indicates that a call does not return. */
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REG_NOTE (NORETURN)
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/* Indicates that an indirect jump is a non-local goto instead of a
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computed goto. */
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REG_NOTE (NON_LOCAL_GOTO)
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/* Indicates that a jump crosses between hot and cold sections in a
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(partitioned) assembly or .o file, and therefore should not be
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reduced to a simpler jump by optimizations. */
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REG_NOTE (CROSSING_JUMP)
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/* This kind of note is generated at each to `setjmp', and similar
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functions that can return twice. */
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REG_NOTE (SETJMP)
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