class RubyVM::InstructionSequence

Parent:: Object

The InstructionSequence class represents a compiled sequence of instructions for the Ruby Virtual Machine.

With it, you can get a handle to the instructions that make up a method or a proc, compile strings of Ruby code down to VM instructions, and disassemble instruction sequences to strings for easy inspection. It is mostly useful if you want to learn how the Ruby VM works, but it also lets you control various settings for the Ruby iseq compiler.

You can find the source for the VM instructions in insns.def in the Ruby source.

The instruction sequence results will almost certainly change as Ruby changes, so example output in this documentation may be different from what you see.

Public Class Methods

compile(source[, file[, path[, line[, options]]]]) → iseq Show source

static VALUE
iseq_s_compile(int argc, VALUE *argv, VALUE self)
{
    VALUE src, file = Qnil, path = Qnil, line = INT2FIX(1), opt = Qnil;

    rb_secure(1);

    rb_scan_args(argc, argv, "14", &src, &file, &path, &line, &opt);
    if (NIL_P(file)) file = rb_str_new2("<compiled>");
    if (NIL_P(line)) line = INT2FIX(1);

    return rb_iseq_compile_with_option(src, file, path, line, 0, opt);
}

Takes source, a String of Ruby code and compiles it to an InstructionSequence.

Optionally takes file, path, and line which describe the filename, absolute path and first line number of the ruby code in source which are metadata attached to the returned iseq.

options, which can be true, false or a Hash, is used to modify the default behavior of the Ruby iseq compiler.

For details regarding valid compile options see ::compile_option=.

RubyVM::InstructionSequence.compile("a = 1 + 2")
#=> <RubyVM::InstructionSequence:<compiled>@<compiled>>

compile_file(file[, options]) → iseq Show source

static VALUE
iseq_s_compile_file(int argc, VALUE *argv, VALUE self)
{
    VALUE file, line = INT2FIX(1), opt = Qnil;
    VALUE parser;
    VALUE f;
    NODE *node;
    const char *fname;
    rb_compile_option_t option;

    rb_secure(1);
    rb_scan_args(argc, argv, "11", &file, &opt);
    FilePathValue(file);
    fname = StringValueCStr(file);

    f = rb_file_open_str(file, "r");

    parser = rb_parser_new();
    node = rb_parser_compile_file(parser, fname, f, NUM2INT(line));

    rb_io_close(f);

    make_compile_option(&option, opt);
    return rb_iseq_new_with_opt(node, rb_str_new2("<main>"), file,
                                rb_realpath_internal(Qnil, file, 1), line, Qfalse,
                                ISEQ_TYPE_TOP, &option);
}

Takes file, a String with the location of a Ruby source file, reads, parses and compiles the file, and returns iseq, the compiled InstructionSequence with source location metadata set.

Optionally takes options, which can be true, false or a Hash, to modify the default behavior of the Ruby iseq compiler.

For details regarding valid compile options see ::compile_option=.

# /tmp/hello.rb
puts "Hello, world!"

# elsewhere
RubyVM::InstructionSequence.compile_file("/tmp/hello.rb")
#=> <RubyVM::InstructionSequence:<main>@/tmp/hello.rb>

compile_option → options Show source

static VALUE
iseq_s_compile_option_get(VALUE self)
{
    return make_compile_option_value(&COMPILE_OPTION_DEFAULT);
}

Returns a hash of default options used by the Ruby iseq compiler.

For details, see ::compile_option=.

compile_option = options Show source

static VALUE
iseq_s_compile_option_set(VALUE self, VALUE opt)
{
    rb_compile_option_t option;
    rb_secure(1);
    make_compile_option(&option, opt);
    COMPILE_OPTION_DEFAULT = option;
    return opt;
}

Sets the default values for various optimizations in the Ruby iseq compiler.

Possible values for options include true, which enables all options, false which disables all options, and nil which leaves all options unchanged.

You can also pass a Hash of options that you want to change, any options not present in the hash will be left unchanged.

Possible option names (which are keys in options) which can be set to true or false include:

:inline_const_cache
:instructions_unification
:operands_unification
:peephole_optimization
:specialized_instruction
:stack_caching
:tailcall_optimization
:trace_instruction

Additionally, :debug_level can be set to an integer.

These default options can be overwritten for a single run of the iseq compiler by passing any of the above values as the options parameter to ::new, ::compile and ::compile_file.

disasm(body) → str Show source

disassemble(body) → str

static VALUE
iseq_s_disasm(VALUE klass, VALUE body)
{
    VALUE iseqval = iseq_s_of(klass, body);
    return NIL_P(iseqval) ? Qnil : rb_iseq_disasm(iseqval);
}

Takes body, a Method or Proc object, and returns a String with the human readable instructions for body.

For a Method object:

# /tmp/method.rb
def hello
  puts "hello, world"
end

puts RubyVM::InstructionSequence.disasm(method(:hello))

Produces:

== disasm: <RubyVM::InstructionSequence:hello@/tmp/method.rb>============
0000 trace            8                                               (   1)
0002 trace            1                                               (   2)
0004 putself
0005 putstring        "hello, world"
0007 send             :puts, 1, nil, 8, <ic:0>
0013 trace            16                                              (   3)
0015 leave                                                            (   2)

For a Proc:

# /tmp/proc.rb
p = proc { num = 1 + 2 }
puts RubyVM::InstructionSequence.disasm(p)

Produces:

== disasm: <RubyVM::InstructionSequence:block in <main>@/tmp/proc.rb>===
== catch table
| catch type: redo   st: 0000 ed: 0012 sp: 0000 cont: 0000
| catch type: next   st: 0000 ed: 0012 sp: 0000 cont: 0012
|------------------------------------------------------------------------
local table (size: 2, argc: 0 [opts: 0, rest: -1, post: 0, block: -1] s1)
[ 2] num
0000 trace            1                                               (   1)
0002 putobject        1
0004 putobject        2
0006 opt_plus         <ic:1>
0008 dup
0009 setlocal         num, 0
0012 leave

disasm(body) → str Show source

disassemble(body) → str

static VALUE
iseq_s_disasm(VALUE klass, VALUE body)
{
    VALUE iseqval = iseq_s_of(klass, body);
    return NIL_P(iseqval) ? Qnil : rb_iseq_disasm(iseqval);
}

Takes body, a Method or Proc object, and returns a String with the human readable instructions for body.

For a Method object:

# /tmp/method.rb
def hello
  puts "hello, world"
end

puts RubyVM::InstructionSequence.disasm(method(:hello))

Produces:

== disasm: <RubyVM::InstructionSequence:hello@/tmp/method.rb>============
0000 trace            8                                               (   1)
0002 trace            1                                               (   2)
0004 putself
0005 putstring        "hello, world"
0007 send             :puts, 1, nil, 8, <ic:0>
0013 trace            16                                              (   3)
0015 leave                                                            (   2)

For a Proc:

# /tmp/proc.rb
p = proc { num = 1 + 2 }
puts RubyVM::InstructionSequence.disasm(p)

Produces:

== disasm: <RubyVM::InstructionSequence:block in <main>@/tmp/proc.rb>===
== catch table
| catch type: redo   st: 0000 ed: 0012 sp: 0000 cont: 0000
| catch type: next   st: 0000 ed: 0012 sp: 0000 cont: 0012
|------------------------------------------------------------------------
local table (size: 2, argc: 0 [opts: 0, rest: -1, post: 0, block: -1] s1)
[ 2] num
0000 trace            1                                               (   1)
0002 putobject        1
0004 putobject        2
0006 opt_plus         <ic:1>
0008 dup
0009 setlocal         num, 0
0012 leave

new(source[, file[, path[, line[, options]]]]) → iseq Show source

static VALUE
iseq_s_compile(int argc, VALUE *argv, VALUE self)
{
    VALUE src, file = Qnil, path = Qnil, line = INT2FIX(1), opt = Qnil;

    rb_secure(1);

    rb_scan_args(argc, argv, "14", &src, &file, &path, &line, &opt);
    if (NIL_P(file)) file = rb_str_new2("<compiled>");
    if (NIL_P(line)) line = INT2FIX(1);

    return rb_iseq_compile_with_option(src, file, path, line, 0, opt);
}

Takes source, a String of Ruby code and compiles it to an InstructionSequence.

Optionally takes file, path, and line which describe the filename, absolute path and first line number of the ruby code in source which are metadata attached to the returned iseq.

options, which can be true, false or a Hash, is used to modify the default behavior of the Ruby iseq compiler.

For details regarding valid compile options see ::compile_option=.

RubyVM::InstructionSequence.compile("a = 1 + 2")
#=> <RubyVM::InstructionSequence:<compiled>@<compiled>>

of(p1) Show source

static VALUE
iseq_s_of(VALUE klass, VALUE body)
{
    VALUE ret = Qnil;
    rb_iseq_t *iseq;

    rb_secure(1);

    if (rb_obj_is_proc(body)) {
        rb_proc_t *proc;
        GetProcPtr(body, proc);
        iseq = proc->block.iseq;
        if (RUBY_VM_NORMAL_ISEQ_P(iseq)) {
            ret = iseq->self;
        }
    }
    else if ((iseq = rb_method_get_iseq(body)) != 0) {
        ret = iseq->self;
    }
    return ret;
}

Returns the instruction sequence containing the given proc or method.

For example, using irb:

# a proc
> p = proc { num = 1 + 2 }
> RubyVM::InstructionSequence.of(p)
> #=> <RubyVM::InstructionSequence:block in irb_binding@(irb)>

# for a method
> def foo(bar); puts bar; end
> RubyVM::InstructionSequence.of(method(:foo))
> #=> <RubyVM::InstructionSequence:foo@(irb)>

Using ::compile_file:

# /tmp/iseq_of.rb
def hello
  puts "hello, world"
end

$a_global_proc = proc { str = 'a' + 'b' }

# in irb
> require '/tmp/iseq_of.rb'

# first the method hello
> RubyVM::InstructionSequence.of(method(:hello))
> #=> #<RubyVM::InstructionSequence:0x007fb73d7cb1d0>

# then the global proc
> RubyVM::InstructionSequence.of($a_global_proc)
> #=> #<RubyVM::InstructionSequence:0x007fb73d7caf78>

Public Instance Methods

absolute_path() Show source

VALUE
rb_iseq_absolute_path(VALUE self)
{
    rb_iseq_t *iseq;
    GetISeqPtr(self, iseq);
    return iseq->location.absolute_path;
}

Returns the absolute path of this instruction sequence.

nil if the iseq was evaluated from a string.

For example, using ::compile_file:

# /tmp/method.rb
def hello
  puts "hello, world"
end

# in irb
> iseq = RubyVM::InstructionSequence.compile_file('/tmp/method.rb')
> iseq.absolute_path #=> /tmp/method.rb

base_label() Show source

VALUE
rb_iseq_base_label(VALUE self)
{
    rb_iseq_t *iseq;
    GetISeqPtr(self, iseq);
    return iseq->location.base_label;
}

Returns the base label of this instruction sequence.

For example, using irb:

iseq = RubyVM::InstructionSequence.compile('num = 1 + 2')
#=> <RubyVM::InstructionSequence:<compiled>@<compiled>>
iseq.base_label
#=> "<compiled>"

Using ::compile_file:

# /tmp/method.rb
def hello
  puts "hello, world"
end

# in irb
> iseq = RubyVM::InstructionSequence.compile_file('/tmp/method.rb')
> iseq.base_label #=> <main>

disasm → str Show source

VALUE
rb_iseq_disasm(VALUE self)
{
    rb_iseq_t *iseqdat = iseq_check(self); /* TODO: rename to iseq */
    VALUE *iseq;
    VALUE str = rb_str_new(0, 0);
    VALUE child = rb_ary_new();
    unsigned int size;
    int i;
    long l;
    ID *tbl;
    size_t n;
    enum {header_minlen = 72};

    rb_secure(1);

    size = iseqdat->iseq_size;

    rb_str_cat2(str, "== disasm: ");

    rb_str_concat(str, iseq_inspect(iseqdat->self));
    if ((l = RSTRING_LEN(str)) < header_minlen) {
        rb_str_resize(str, header_minlen);
        memset(RSTRING_PTR(str) + l, '=', header_minlen - l);
    }
    rb_str_cat2(str, "\n");

    /* show catch table information */
    if (iseqdat->catch_table) {
        rb_str_cat2(str, "== catch table\n");
    }
    if (iseqdat->catch_table) for (i = 0; i < iseqdat->catch_table->size; i++) {
        struct iseq_catch_table_entry *entry = &iseqdat->catch_table->entries[i];
        rb_str_catf(str,
                    "| catch type: %-6s st: %04d ed: %04d sp: %04d cont: %04d\n",
                    catch_type((int)entry->type), (int)entry->start,
                    (int)entry->end, (int)entry->sp, (int)entry->cont);
        if (entry->iseq) {
            rb_str_concat(str, rb_iseq_disasm(entry->iseq));
        }
    }
    if (iseqdat->catch_table) {
        rb_str_cat2(str, "|-------------------------------------"
                    "-----------------------------------\n");
    }

    /* show local table information */
    tbl = iseqdat->local_table;

    if (tbl) {
        rb_str_catf(str,
                    "local table (size: %d, argc: %d "
                    "[opts: %d, rest: %d, post: %d, block: %d, kw: %d@%d, kwrest: %d])\n",
                    iseqdat->local_size,
                    iseqdat->param.lead_num,
                    iseqdat->param.opt_num,
                    iseqdat->param.flags.has_rest ? iseqdat->param.rest_start : -1,
                    iseqdat->param.post_num,
                    iseqdat->param.flags.has_block ? iseqdat->param.block_start : -1,
                    iseqdat->param.flags.has_kw ? iseqdat->param.keyword->num : -1,
                    iseqdat->param.flags.has_kw ? iseqdat->param.keyword->required_num : -1,
                    iseqdat->param.flags.has_kwrest ? iseqdat->param.keyword->rest_start : -1);

        for (i = 0; i < iseqdat->local_table_size; i++) {
            long width;
            VALUE name = id_to_name(tbl[i], 0);
            char argi[0x100] = "";
            char opti[0x100] = "";

            if (iseqdat->param.flags.has_opt) {
                int argc = iseqdat->param.lead_num;
                int opts = iseqdat->param.opt_num;
                if (i >= argc && i < argc + opts) {
                    snprintf(opti, sizeof(opti), "Opt=%"PRIdVALUE,
                             iseqdat->param.opt_table[i - argc]);
                }
            }

            snprintf(argi, sizeof(argi), "%s%s%s%s%s", /* arg, opts, rest, post  block */
                     iseqdat->param.lead_num > i ? "Arg" : "",
                     opti,
                     (iseqdat->param.flags.has_rest && iseqdat->param.rest_start == i) ? "Rest" : "",
                     (iseqdat->param.flags.has_post && iseqdat->param.post_start <= i && i < iseqdat->param.post_start + iseqdat->param.post_num) ? "Post" : "",
                     (iseqdat->param.flags.has_block && iseqdat->param.block_start == i) ? "Block" : "");

            rb_str_catf(str, "[%2d] ", iseqdat->local_size - i);
            width = RSTRING_LEN(str) + 11;
            if (name)
                rb_str_append(str, name);
            else
                rb_str_cat2(str, "?");
            if (*argi) rb_str_catf(str, "<%s>", argi);
            if ((width -= RSTRING_LEN(str)) > 0) rb_str_catf(str, "%*s", (int)width, "");
        }
        rb_str_cat2(str, "\n");
    }

    /* show each line */
    iseq = rb_iseq_original_iseq(iseqdat);
    for (n = 0; n < size;) {
        n += rb_iseq_disasm_insn(str, iseq, n, iseqdat, child);
    }

    for (i = 0; i < RARRAY_LEN(child); i++) {
        VALUE isv = rb_ary_entry(child, i);
        rb_str_concat(str, rb_iseq_disasm(isv));
    }

    return str;
}

Returns the instruction sequence as a String in human readable form.

puts RubyVM::InstructionSequence.compile('1 + 2').disasm

Produces:

== disasm: <RubyVM::InstructionSequence:<compiled>@<compiled>>==========
0000 trace            1                                               (   1)
0002 putobject        1
0004 putobject        2
0006 opt_plus         <ic:1>
0008 leave

disassemble → str Show source

VALUE
rb_iseq_disasm(VALUE self)
{
    rb_iseq_t *iseqdat = iseq_check(self); /* TODO: rename to iseq */
    VALUE *iseq;
    VALUE str = rb_str_new(0, 0);
    VALUE child = rb_ary_new();
    unsigned int size;
    int i;
    long l;
    ID *tbl;
    size_t n;
    enum {header_minlen = 72};

    rb_secure(1);

    size = iseqdat->iseq_size;

    rb_str_cat2(str, "== disasm: ");

    rb_str_concat(str, iseq_inspect(iseqdat->self));
    if ((l = RSTRING_LEN(str)) < header_minlen) {
        rb_str_resize(str, header_minlen);
        memset(RSTRING_PTR(str) + l, '=', header_minlen - l);
    }
    rb_str_cat2(str, "\n");

    /* show catch table information */
    if (iseqdat->catch_table) {
        rb_str_cat2(str, "== catch table\n");
    }
    if (iseqdat->catch_table) for (i = 0; i < iseqdat->catch_table->size; i++) {
        struct iseq_catch_table_entry *entry = &iseqdat->catch_table->entries[i];
        rb_str_catf(str,
                    "| catch type: %-6s st: %04d ed: %04d sp: %04d cont: %04d\n",
                    catch_type((int)entry->type), (int)entry->start,
                    (int)entry->end, (int)entry->sp, (int)entry->cont);
        if (entry->iseq) {
            rb_str_concat(str, rb_iseq_disasm(entry->iseq));
        }
    }
    if (iseqdat->catch_table) {
        rb_str_cat2(str, "|-------------------------------------"
                    "-----------------------------------\n");
    }

    /* show local table information */
    tbl = iseqdat->local_table;

    if (tbl) {
        rb_str_catf(str,
                    "local table (size: %d, argc: %d "
                    "[opts: %d, rest: %d, post: %d, block: %d, kw: %d@%d, kwrest: %d])\n",
                    iseqdat->local_size,
                    iseqdat->param.lead_num,
                    iseqdat->param.opt_num,
                    iseqdat->param.flags.has_rest ? iseqdat->param.rest_start : -1,
                    iseqdat->param.post_num,
                    iseqdat->param.flags.has_block ? iseqdat->param.block_start : -1,
                    iseqdat->param.flags.has_kw ? iseqdat->param.keyword->num : -1,
                    iseqdat->param.flags.has_kw ? iseqdat->param.keyword->required_num : -1,
                    iseqdat->param.flags.has_kwrest ? iseqdat->param.keyword->rest_start : -1);

        for (i = 0; i < iseqdat->local_table_size; i++) {
            long width;
            VALUE name = id_to_name(tbl[i], 0);
            char argi[0x100] = "";
            char opti[0x100] = "";

            if (iseqdat->param.flags.has_opt) {
                int argc = iseqdat->param.lead_num;
                int opts = iseqdat->param.opt_num;
                if (i >= argc && i < argc + opts) {
                    snprintf(opti, sizeof(opti), "Opt=%"PRIdVALUE,
                             iseqdat->param.opt_table[i - argc]);
                }
            }

            snprintf(argi, sizeof(argi), "%s%s%s%s%s", /* arg, opts, rest, post  block */
                     iseqdat->param.lead_num > i ? "Arg" : "",
                     opti,
                     (iseqdat->param.flags.has_rest && iseqdat->param.rest_start == i) ? "Rest" : "",
                     (iseqdat->param.flags.has_post && iseqdat->param.post_start <= i && i < iseqdat->param.post_start + iseqdat->param.post_num) ? "Post" : "",
                     (iseqdat->param.flags.has_block && iseqdat->param.block_start == i) ? "Block" : "");

            rb_str_catf(str, "[%2d] ", iseqdat->local_size - i);
            width = RSTRING_LEN(str) + 11;
            if (name)
                rb_str_append(str, name);
            else
                rb_str_cat2(str, "?");
            if (*argi) rb_str_catf(str, "<%s>", argi);
            if ((width -= RSTRING_LEN(str)) > 0) rb_str_catf(str, "%*s", (int)width, "");
        }
        rb_str_cat2(str, "\n");
    }

    /* show each line */
    iseq = rb_iseq_original_iseq(iseqdat);
    for (n = 0; n < size;) {
        n += rb_iseq_disasm_insn(str, iseq, n, iseqdat, child);
    }

    for (i = 0; i < RARRAY_LEN(child); i++) {
        VALUE isv = rb_ary_entry(child, i);
        rb_str_concat(str, rb_iseq_disasm(isv));
    }

    return str;
}

Returns the instruction sequence as a String in human readable form.

puts RubyVM::InstructionSequence.compile('1 + 2').disasm

Produces:

== disasm: <RubyVM::InstructionSequence:<compiled>@<compiled>>==========
0000 trace            1                                               (   1)
0002 putobject        1
0004 putobject        2
0006 opt_plus         <ic:1>
0008 leave

eval → obj Show source

static VALUE
iseq_eval(VALUE self)
{
    rb_secure(1);
    return rb_iseq_eval(self);
}

Evaluates the instruction sequence and returns the result.

RubyVM::InstructionSequence.compile("1 + 2").eval #=> 3

first_lineno() Show source

VALUE
rb_iseq_first_lineno(VALUE self)
{
    rb_iseq_t *iseq;
    GetISeqPtr(self, iseq);
    return iseq->location.first_lineno;
}

Returns the number of the first source line where the instruction sequence was loaded from.

For example, using irb:

iseq = RubyVM::InstructionSequence.compile('num = 1 + 2')
#=> <RubyVM::InstructionSequence:<compiled>@<compiled>>
iseq.first_lineno
#=> 1

inspect() Show source

static VALUE
iseq_inspect(VALUE self)
{
    rb_iseq_t *iseq;
    GetISeqPtr(self, iseq);
    if (!iseq->location.label) {
        return rb_sprintf("#<%s: uninitialized>", rb_obj_classname(self));
    }

    return rb_sprintf("<%s:%s@%s>",
                      rb_obj_classname(self),
                      RSTRING_PTR(iseq->location.label), RSTRING_PTR(iseq->location.path));
}

Returns a human-readable string representation of this instruction sequence, including the label and path.

label() Show source

VALUE
rb_iseq_label(VALUE self)
{
    rb_iseq_t *iseq;
    GetISeqPtr(self, iseq);
    return iseq->location.label;
}

Returns the label of this instruction sequence.

<main> if it's at the top level, <compiled> if it was evaluated from a string.

For example, using irb:

iseq = RubyVM::InstructionSequence.compile('num = 1 + 2')
#=> <RubyVM::InstructionSequence:<compiled>@<compiled>>
iseq.label
#=> "<compiled>"

Using ::compile_file:

# /tmp/method.rb
def hello
  puts "hello, world"
end

# in irb
> iseq = RubyVM::InstructionSequence.compile_file('/tmp/method.rb')
> iseq.label #=> <main>

line_trace_all() Show source

VALUE
rb_iseq_line_trace_all(VALUE iseqval)
{
    VALUE result = rb_ary_new();
    rb_iseq_line_trace_each(iseqval, collect_trace, (void *)result);
    return result;
}

Experimental MRI specific feature, only available as C level api.

Returns all specified_line events.

line_trace_specify(p1, p2) Show source

VALUE
rb_iseq_line_trace_specify(VALUE iseqval, VALUE pos, VALUE set)
{
    struct set_specifc_data data;

    data.prev = 0;
    data.pos = NUM2INT(pos);
    if (data.pos < 0) rb_raise(rb_eTypeError, "`pos' is negative");

    switch (set) {
      case Qtrue:  data.set = 1; break;
      case Qfalse: data.set = 0; break;
      default:
        rb_raise(rb_eTypeError, "`set' should be true/false");
    }

    rb_iseq_line_trace_each(iseqval, line_trace_specify, (void *)&data);

    if (data.prev == 0) {
        rb_raise(rb_eTypeError, "`pos' is out of range.");
    }
    return data.prev == 1 ? Qtrue : Qfalse;
}

Experimental MRI specific feature, only available as C level api.

Set a specified_line event at the given line position, if the set parameter is true.

This method is useful for building a debugger breakpoint at a specific line.

A TypeError is raised if set is not boolean.

If pos is a negative integer a TypeError exception is raised.

path() Show source

VALUE
rb_iseq_path(VALUE self)
{
    rb_iseq_t *iseq;
    GetISeqPtr(self, iseq);
    return iseq->location.path;
}

Returns the path of this instruction sequence.

<compiled> if the iseq was evaluated from a string.

For example, using irb:

iseq = RubyVM::InstructionSequence.compile('num = 1 + 2')
#=> <RubyVM::InstructionSequence:<compiled>@<compiled>>
iseq.path
#=> "<compiled>"

Using ::compile_file:

# /tmp/method.rb
def hello
  puts "hello, world"
end

# in irb
> iseq = RubyVM::InstructionSequence.compile_file('/tmp/method.rb')
> iseq.path #=> /tmp/method.rb

to_a → ary Show source

static VALUE
iseq_to_a(VALUE self)
{
    rb_iseq_t *iseq = iseq_check(self);
    rb_secure(1);
    return iseq_data_to_ary(iseq);
}

Returns an Array with 14 elements representing the instruction sequence with the following data:

magic

A string identifying the data format. Always YARVInstructionSequence/SimpleDataFormat.

major_version

The major version of the instruction sequence.

minor_version

The minor version of the instruction sequence.

format_type

A number identifying the data format. Always 1.

misc

A hash containing:

:arg_size: the total number of arguments taken by the method or the block (0 if iseq doesn't represent a method or block)
:local_size: the number of local variables + 1
:stack_max: used in calculating the stack depth at which a SystemStackError is thrown.

label

The name of the context (block, method, class, module, etc.) that this instruction sequence belongs to.

<main> if it's at the top level, <compiled> if it was evaluated from a string.

path

The relative path to the Ruby file where the instruction sequence was loaded from.

<compiled> if the iseq was evaluated from a string.

absolute_path

The absolute path to the Ruby file where the instruction sequence was loaded from.

nil if the iseq was evaluated from a string.

first_lineno

The number of the first source line where the instruction sequence was loaded from.

type

The type of the instruction sequence.

Valid values are :top, :method, :block, :class, :rescue, :ensure, :eval, :main, and :defined_guard.

locals

An array containing the names of all arguments and local variables as symbols.

params

An Hash object containing parameter information.

More info about these values can be found in vm_core.h.

catch_table

A list of exceptions and control flow operators (rescue, next, redo, break, etc.).

bytecode

An array of arrays containing the instruction names and operands that make up the body of the instruction sequence.

Note that this format is MRI specific and version dependent.

Ruby Core © 1993–2017 Yukihiro Matsumoto
Licensed under the Ruby License.
Ruby Standard Library © contributors
Licensed under their own licenses.