github.com/huandu/go@v0.0.0-20151114150818-04e615e41150/src/cmd/internal/obj/funcdata.go (about)

     1  // Inferno utils/5c/list.c
     2  // http://code.google.com/p/inferno-os/source/browse/utils/5c/list.c
     3  //
     4  //	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
     5  //	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
     6  //	Portions Copyright © 1997-1999 Vita Nuova Limited
     7  //	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
     8  //	Portions Copyright © 2004,2006 Bruce Ellis
     9  //	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
    10  //	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
    11  //	Portions Copyright © 2009 The Go Authors.  All rights reserved.
    12  //
    13  // Permission is hereby granted, free of charge, to any person obtaining a copy
    14  // of this software and associated documentation files (the "Software"), to deal
    15  // in the Software without restriction, including without limitation the rights
    16  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    17  // copies of the Software, and to permit persons to whom the Software is
    18  // furnished to do so, subject to the following conditions:
    19  //
    20  // The above copyright notice and this permission notice shall be included in
    21  // all copies or substantial portions of the Software.
    22  //
    23  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    24  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    25  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
    26  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    27  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    28  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    29  // THE SOFTWARE.
    30  
    31  package obj
    32  
    33  // Copyright 2013 The Go Authors.  All rights reserved.
    34  // Use of this source code is governed by a BSD-style
    35  // license that can be found in the LICENSE file.
    36  
    37  // This file defines the IDs for PCDATA and FUNCDATA instructions
    38  // in Go binaries. It is included by assembly sources, so it must
    39  // be written using #defines.
    40  //
    41  // The Go compiler also #includes this file, for now.
    42  //
    43  // symtab.go also contains a copy of these constants.
    44  
    45  // Pseudo-assembly statements.
    46  
    47  // GO_ARGS, GO_RESULTS_INITIALIZED, and NO_LOCAL_POINTERS are macros
    48  // that communicate to the runtime information about the location and liveness
    49  // of pointers in an assembly function's arguments, results, and stack frame.
    50  // This communication is only required in assembly functions that make calls
    51  // to other functions that might be preempted or grow the stack.
    52  // NOSPLIT functions that make no calls do not need to use these macros.
    53  
    54  // GO_ARGS indicates that the Go prototype for this assembly function
    55  // defines the pointer map for the function's arguments.
    56  // GO_ARGS should be the first instruction in a function that uses it.
    57  // It can be omitted if there are no arguments at all.
    58  // GO_ARGS is inserted implicitly by the linker for any function
    59  // that also has a Go prototype and therefore is usually not necessary
    60  // to write explicitly.
    61  
    62  // GO_RESULTS_INITIALIZED indicates that the assembly function
    63  // has initialized the stack space for its results and that those results
    64  // should be considered live for the remainder of the function.
    65  
    66  // NO_LOCAL_POINTERS indicates that the assembly function stores
    67  // no pointers to heap objects in its local stack variables.
    68  
    69  // ArgsSizeUnknown is set in Func.argsize to mark all functions
    70  // whose argument size is unknown (C vararg functions, and
    71  // assembly code without an explicit specification).
    72  // This value is generated by the compiler, assembler, or linker.
    73  const (
    74  	PCDATA_StackMapIndex       = 0
    75  	FUNCDATA_ArgsPointerMaps   = 0
    76  	FUNCDATA_LocalsPointerMaps = 1
    77  	FUNCDATA_DeadValueMaps     = 2
    78  	ArgsSizeUnknown            = -0x80000000
    79  )