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update compiler.texi
* doc/ref/compiler.texi (Compiler Tower): Update for removal of version from <language>, and add joiner and make-default-environment fields. Update examples. (The Scheme Compiler): Update for `macroexpand' instead of `sc-expand', and that the environment must be a module. (Tree-IL): Update for new Tree-IL, and change from "vars" to "gensyms". (GLIL): Update for new GLIL, including preludes and prompts. (Assembly): Update for current output (which seems quite verbose). (Bytecode and Objcode): Update for current output, and some procedure name changes.
This commit is contained in:
Andy Wingo
parent
93f63467e6
commit
41e64dd73c
1 changed files with 205 additions and 138 deletions
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@ -53,8 +53,9 @@ Languages are registered in the module, @code{(system base language)}:
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They are registered with the @code{define-language} form.
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@deffn {Scheme Syntax} define-language @
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name title version reader printer @
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[parser=#f] [compilers='()] [decompilers='()] [evaluator=#f]
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name title reader printer @
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[parser=#f] [compilers='()] [decompilers='()] [evaluator=#f] @
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[joiner=#f] [make-default-environment=make-fresh-user-module]
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Define a language.
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This syntax defines a @code{#<language>} object, bound to @var{name}
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@ -64,13 +65,13 @@ for Scheme:
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@example
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(define-language scheme
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#:title "Guile Scheme"
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#:version "0.5"
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#:reader read
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#:title "Scheme"
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#:reader (lambda (port env) ...)
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#:compilers `((tree-il . ,compile-tree-il))
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#:decompilers `((tree-il . ,decompile-tree-il))
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#:evaluator (lambda (x module) (primitive-eval x))
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#:printer write)
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#:printer write
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#:make-default-environment (lambda () ...))
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@end example
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@end deffn
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@ -79,17 +80,11 @@ they present a uniform interface to the read-eval-print loop. This
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allows the user to change the current language of the REPL:
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@example
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$ guile
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Guile Scheme interpreter 0.5 on Guile 1.9.0
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Copyright (C) 2001-2008 Free Software Foundation, Inc.
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Enter `,help' for help.
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scheme@@(guile-user)> ,language tree-il
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Tree Intermediate Language interpreter 1.0 on Guile 1.9.0
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Copyright (C) 2001-2008 Free Software Foundation, Inc.
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Enter `,help' for help.
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tree-il@@(guile-user)>
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Happy hacking with Tree Intermediate Language! To switch back, type `,L scheme'.
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tree-il@@(guile-user)> ,L scheme
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Happy hacking with Scheme! To switch back, type `,L tree-il'.
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scheme@@(guile-user)>
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@end example
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Languages can be looked up by name, as they were above.
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@ -126,9 +121,9 @@ and target languages.
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The normal tower of languages when compiling Scheme goes like this:
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@itemize
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@item Scheme, which we know and love
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@item Scheme
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@item Tree Intermediate Language (Tree-IL)
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@item Guile Low Intermediate Language (GLIL)
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@item Guile Lowlevel Intermediate Language (GLIL)
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@item Assembly
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@item Bytecode
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@item Objcode
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@ -195,14 +190,14 @@ The Scheme-to-Tree-IL expander may be invoked using the generic
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Or, since Tree-IL is so close to Scheme, it is often useful to expand
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Scheme to Tree-IL, then translate back to Scheme. For that reason the
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expander provides two interfaces. The former is equivalent to calling
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@code{(sc-expand '(+ 1 2) 'c)}, where the @code{'c} is for
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@code{(macroexpand '(+ 1 2) 'c)}, where the @code{'c} is for
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``compile''. With @code{'e} (the default), the result is translated
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back to Scheme:
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@lisp
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(sc-expand '(+ 1 2))
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(macroexpand '(+ 1 2))
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@result{} (+ 1 2)
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(sc-expand '(let ((x 10)) (* x x)))
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(macroexpand '(let ((x 10)) (* x x)))
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@result{} (let ((x84 10)) (* x84 x84))
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@end lisp
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@ -214,9 +209,9 @@ lexical binding only has one name. It is for this reason that the
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much information we would lose if we translated to Scheme directly:
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lexical variable names, source locations, and module hygiene.
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Note however that @code{sc-expand} does not have the same signature as
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@code{compile-tree-il}. @code{compile-tree-il} is a small wrapper
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around @code{sc-expand}, to make it conform to the general form of
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Note however that @code{macroexpand} does not have the same signature
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as @code{compile-tree-il}. @code{compile-tree-il} is a small wrapper
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around @code{macroexpand}, to make it conform to the general form of
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compiler procedures in Guile's language tower.
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Compiler procedures take three arguments: an expression, an
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@ -235,17 +230,10 @@ which puts the user in the @code{(foo)} module. That is purpose of the
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``continuation environment''; you would pass it as the environment
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when compiling the subsequent expression.
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For Scheme, an environment may be one of two things:
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@itemize
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@item @code{#f}, in which case compilation is performed in the context
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of the current module; or
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@item a module, which specifies the context of the compilation.
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@end itemize
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By default, the @code{compile} and @code{compile-file} procedures
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compile in a fresh module, such that bindings and macros introduced by
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the expression being compiled are isolated:
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For Scheme, an environment is a module. By default, the @code{compile}
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and @code{compile-file} procedures compile in a fresh module, such
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that bindings and macros introduced by the expression being compiled
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are isolated:
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@example
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(eq? (current-module) (compile '(current-module)))
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@ -289,12 +277,12 @@ expanded, pre-analyzed Scheme.
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Tree-IL is ``structured'' in the sense that its representation is
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based on records, not S-expressions. This gives a rigidity to the
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language that ensures that compiling to a lower-level language only
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requires a limited set of transformations. Practically speaking,
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consider the Tree-IL type, @code{<const>}, which has two fields,
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@code{src} and @code{exp}. Instances of this type are records created
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via @code{make-const}, and whose fields are accessed as
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@code{const-src}, and @code{const-exp}. There is also a predicate,
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@code{const?}. @xref{Records}, for more information on records.
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requires a limited set of transformations. For example, the Tree-IL
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type @code{<const>} is a record type with two fields, @code{src} and
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@code{exp}. Instances of this type are created via @code{make-const}.
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Fields of this type are accessed via the @code{const-src} and
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@code{const-exp} procedures. There is also a predicate, @code{const?}.
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@xref{Records}, for more information on records.
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@c alpha renaming
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@ -318,10 +306,7 @@ Users may program with this format directly at the REPL:
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@example
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scheme@@(guile-user)> ,language tree-il
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Tree Intermediate Language interpreter 1.0 on Guile 1.9.0
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Copyright (C) 2001-2008 Free Software Foundation, Inc.
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Enter `,help' for help.
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Happy hacking with Tree Intermediate Language! To switch back, type `,L scheme'.
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tree-il@@(guile-user)> (apply (primitive +) (const 32) (const 10))
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@result{} 42
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@end example
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@ -408,25 +393,104 @@ A procedure call.
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@deftpx {External Representation} (begin . @var{exps})
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Like Scheme's @code{begin}.
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@end deftp
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@deftp {Scheme Variable} <lambda> src names vars meta body
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@deftpx {External Representation} (lambda @var{names} @var{vars} @var{meta} @var{body})
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A closure. @var{names} is original binding form, as given in the
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source code, which may be an improper list. @var{vars} are gensyms
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corresponding to the @var{names}. @var{meta} is an association list of
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properties. The actual @var{body} is a single Tree-IL expression.
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@deftp {Scheme Variable} <lambda> src meta body
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@deftpx {External Representation} (lambda @var{meta} @var{body})
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A closure. @var{meta} is an association list of properties for the
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procedure. @var{body} is a single Tree-IL expression of type
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@code{<lambda-case>}. As the @code{<lambda-case>} clause can chain to
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an alternate clause, this makes Tree-IL's @code{<lambda>} have the
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expressiveness of Scheme's @code{case-lambda}.
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@end deftp
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@deftp {Scheme Variable} <let> src names vars vals exp
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@deftpx {External Representation} (let @var{names} @var{vars} @var{vals} @var{exp})
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@deftp {Scheme Variable} <lambda-case> req opt rest kw inits gensyms body alternate
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@deftpx {External Representation} @
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(lambda-case ((@var{req} @var{opt} @var{rest} @var{kw} @var{inits} @var{gensyms})@
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@var{body})@
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[@var{alternate}])
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One clause of a @code{case-lambda}. A @code{lambda} expression in
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Scheme is treated as a @code{case-lambda} with one clause.
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@var{req} is a list of the procedure's required arguments, as symbols.
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@var{opt} is a list of the optional arguments, or @code{#f} if there
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are no optional arguments. @var{rest} is the name of the rest
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argument, or @code{#f}.
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@var{kw} is a list of the form, @code{(@var{allow-other-keys?}
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(@var{keyword} @var{name} @var{var}) ...)}, where @var{keyword} is the
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keyword corresponding to the argument named @var{name}, and whose
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corresponding gensym is @var{var}. @var{inits} are tree-il expressions
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corresponding to all of the optional and keyword argumens, evaluated
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to bind variables whose value is not supplied by the procedure caller.
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Each @var{init} expression is evaluated in the lexical context of
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previously bound variables, from left to right.
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@var{gensyms} is a list of gensyms corresponding to all arguments:
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first all of the required arguments, then the optional arguments if
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any, then the rest argument if any, then all of the keyword arguments.
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@var{body} is the body of the clause. If the procedure is called with
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an appropriate number of arguments, @var{body} is evaluated in tail
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position. Otherwise, if there is a @var{consequent}, it should be a
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@code{<lambda-case>} expression, representing the next clause to try.
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If there is no @var{consequent}, a wrong-number-of-arguments error is
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signaled.
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@end deftp
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@deftp {Scheme Variable} <let> src names gensyms vals exp
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@deftpx {External Representation} (let @var{names} @var{gensyms} @var{vals} @var{exp})
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Lexical binding, like Scheme's @code{let}. @var{names} are the
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original binding names, @var{vars} are gensyms corresponding to the
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original binding names, @var{gensyms} are gensyms corresponding to the
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@var{names}, and @var{vals} are Tree-IL expressions for the values.
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@var{exp} is a single Tree-IL expression.
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@end deftp
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@deftp {Scheme Variable} <letrec> src names vars vals exp
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@deftpx {External Representation} (letrec @var{names} @var{vars} @var{vals} @var{exp})
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@deftp {Scheme Variable} <letrec> src names gensyms vals exp
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@deftpx {External Representation} (letrec @var{names} @var{gensyms} @var{vals} @var{exp})
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A version of @code{<let>} that creates recursive bindings, like
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Scheme's @code{letrec}.
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@end deftp
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@deftp {Scheme Variable} <dynlet> fluids vals body
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@deftpx {External Representation} (dynlet @var{fluids} @var{vals} @var{body})
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Dynamic binding; the equivalent of Scheme's @code{with-fluids}.
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@var{fluids} should be a list of Tree-IL expressions that will
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evaluate to fluids, and @var{vals} a corresponding list of expressions
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to bind to the fluids during the dynamic extent of the evaluation of
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@var{body}.
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@end deftp
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@deftp {Scheme Variable} <dynref> fluid
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@deftpx {External Representation} (dynref @var{fluid})
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A dynamic variable reference. @var{fluid} should be a Tree-IL
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expression evaluating to a fluid.
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@end deftp
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@deftp {Scheme Variable} <dynset> fluid exp
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@deftpx {External Representation} (dynset @var{fluid} @var{exp})
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A dynamic variable set. @var{fluid}, a Tree-IL expression evaluating
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to a fluid, will be set to the result of evaluating @var{exp}.
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@end deftp
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@deftp {Scheme Variable} <dynwind> winder body unwinder
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@deftpx {External Representation} (dynwind @var{winder} @var{body} @var{unwinder})
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A @code{dynamic-wind}. @var{winder} and @var{unwinder} should both
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evaluate to thunks. Ensure that the winder and the unwinder are called
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before entering and after leaving @var{body}. Note that @var{body} is
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an expression, without a thunk wrapper.
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@end deftp
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@deftp {Scheme Variable} <prompt> tag body handler
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@deftpx {External Representation} (prompt @var{tag} @var{body} @var{handler})
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A dynamic prompt. Instates a prompt named @var{tag}, an expression,
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during the dynamic extent of the execution of @var{body}, also an
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expression. If an abort occurs to this prompt, control will be passed
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to @var{handler}, a @code{<lambda-case>} expression with no optional
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or keyword arguments, and no alternate. The first argument to the
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@code{<lambda-case>} will be the captured continuation, and then all
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of the values passed to the abort. @xref{Prompts}, for more
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information.
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@end deftp
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@deftp {Scheme Variable} <abort> tag args tail
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@deftpx {External Representation} (abort @var{tag} @var{args} @var{tail})
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An abort to the nearest prompt with the name @var{tag}, an expression.
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@var{args} should be a list of expressions to pass to the prompt's
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handler, and @var{tail} should be an expression that will evaluate to
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a list of additional arguments. An abort will save the partial
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continuation, which may later be reinstated, resulting in the
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@code{<abort>} expression evaluating to some number of values.
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@end deftp
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There are two Tree-IL constructs that are not normally produced by
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higher-level compilers, but instead are generated during the
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@ -435,17 +499,17 @@ compiler does. Users should not generate these expressions directly,
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unless they feel very clever, as the default analysis pass will
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generate them as necessary.
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@deftp {Scheme Variable} <let-values> src names vars exp body
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@deftpx {External Representation} (let-values @var{names} @var{vars} @var{exp} @var{body})
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@deftp {Scheme Variable} <let-values> src names gensyms exp body
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@deftpx {External Representation} (let-values @var{names} @var{gensyms} @var{exp} @var{body})
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Like Scheme's @code{receive} -- binds the values returned by
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evaluating @code{exp} to the @code{lambda}-like bindings described by
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@var{vars}. That is to say, @var{vars} may be an improper list.
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@var{gensyms}. That is to say, @var{gensyms} may be an improper list.
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@code{<let-values>} is an optimization of @code{<application>} of the
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primitive, @code{call-with-values}.
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@end deftp
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@deftp {Scheme Variable} <fix> src names vars vals body
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@deftpx {External Representation} (fix @var{names} @var{vars} @var{vals} @var{body})
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@deftp {Scheme Variable} <fix> src names gensyms vals body
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@deftpx {External Representation} (fix @var{names} @var{gensyms} @var{vals} @var{body})
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Like @code{<letrec>}, but only for @var{vals} that are unset
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@code{lambda} expressions.
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@ -470,19 +534,38 @@ Interested readers are encouraged to read the implementation in
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@node GLIL
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@subsection GLIL
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Guile Low Intermediate Language (GLIL) is a structured intermediate
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Guile Lowlevel Intermediate Language (GLIL) is a structured intermediate
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language whose expressions more closely approximate Guile's VM
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instruction set. Its expression types are defined in @code{(language
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glil)}.
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@deftp {Scheme Variable} <glil-program> nargs nrest nlocs meta . body
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@deftp {Scheme Variable} <glil-program> meta . body
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A unit of code that at run-time will correspond to a compiled
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procedure. @var{nargs} @var{nrest} and @var{nlocs} collectively define
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the program's arity; see @ref{Compiled Procedures}, for more
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information. @var{meta} should be an alist of properties, as in
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procedure. @var{meta} should be an alist of properties, as in
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Tree-IL's @code{<lambda>}. @var{body} is an ordered list of GLIL
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expressions.
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@end deftp
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@deftp {Scheme Variable} <glil-std-prelude> nreq nlocs else-label
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A prologue for a function with no optional, keyword, or rest
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arguments. @var{nreq} is the number of required arguments. @var{nlocs}
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the total number of local variables, including the arguments. If the
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procedure was not given exactly @var{nreq} arguments, control will
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jump to @var{else-label}, if given, or otherwise signal an error.
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@end deftp
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@deftp {Scheme Variable} <glil-opt-prelude> nreq nopt rest nlocs else-label
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A prologue for a function with optional or rest arguments. Like
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@code{<glil-std-prelude>}, with the addition that @var{nopt} is the
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number of optional arguments (possibly zero) and @var{rest} is an
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index of a local variable at which to bind a rest argument, or
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@code{#f} if there is no rest argument.
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@end deftp
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@deftp {Scheme Variable} <glil-kw-prelude> nreq nopt rest kw allow-other-keys? nlocs else-label
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A prologue for a function with keyword arguments. Like
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@code{<glil-opt-prelude>}, with the addition that @var{kw} is a list
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of keyword arguments, and @var{allow-other-keys?} is a flag indicating
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whether to allow unknown keys. @xref{Function Prologue Instructions,
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@code{bind-kwargs}}, for details on the format of @var{kw}.
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@end deftp
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@deftp {Scheme Variable} <glil-bind> . vars
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An advisory expression that notes a liveness extent for a set of
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variables. @var{vars} is a list of @code{(@var{name} @var{type}
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@ -529,10 +612,10 @@ list, or a pair or vector of constants.
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@end deftp
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@deftp {Scheme Variable} <glil-lexical> local? boxed? op index
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Accesses a lexically bound variable. If the variable is not
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@var{local?} it is free. All variables may have @code{ref} and
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@code{set} as their @var{op}. Boxed variables may also have the
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@var{op}s @code{box}, @code{empty-box}, and @code{fix}, which
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correspond in semantics to the VM instructions @code{box},
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@var{local?} it is free. All variables may have @code{ref},
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@code{set}, and @code{bound?} as their @var{op}. Boxed variables may
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also have the @var{op}s @code{box}, @code{empty-box}, and @code{fix},
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which correspond in semantics to the VM instructions @code{box},
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@code{empty-box}, and @code{fix-closure}. @xref{Stack Layout}, for
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more information.
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@end deftp
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@ -565,20 +648,22 @@ corresponding to the multiple-value return address for the call. See
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the notes on @code{mv-call} in @ref{Procedure Call and Return
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Instructions}, for more information.
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@end deftp
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@deftp {Scheme Variable} <glil-prompt> label escape-only?
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Push a dynamic prompt into the stack, with a handler at @var{label}.
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@var{escape-only?} is a flag that is propagated to the prompt,
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allowing an abort to avoid capturing a continuation in some cases.
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||||
@xref{Prompts}, for more information.
|
||||
@end deftp
|
||||
|
||||
Users may enter in GLIL at the REPL as well, though there is a bit
|
||||
more bookkeeping to do. Since GLIL needs the set of variables to be
|
||||
declared explicitly in a @code{<glil-program>}, GLIL expressions must
|
||||
be wrapped in a thunk that declares the arity of the expression:
|
||||
more bookkeeping to do:
|
||||
|
||||
@example
|
||||
scheme@@(guile-user)> ,language glil
|
||||
Guile Lowlevel Intermediate Language (GLIL) interpreter 0.3 on
|
||||
Guile 1.9.0
|
||||
Copyright (C) 2001-2008 Free Software Foundation, Inc.
|
||||
|
||||
Enter `,help' for help.
|
||||
glil@@(guile-user)> (program 0 0 0 () (const 3) (call return 1))
|
||||
Happy hacking with Guile Lowlevel Intermediate Language (GLIL)!
|
||||
To switch back, type `,L scheme'.
|
||||
glil@@(guile-user)> (program () (std-prelude 0 0 #f)
|
||||
(const 3) (call return 1))
|
||||
@result{} 3
|
||||
@end example
|
||||
|
||||
|
|
@ -624,44 +709,33 @@ to play around with it at the REPL, as can be seen in this annotated
|
|||
example:
|
||||
|
||||
@example
|
||||
scheme@@(guile-user)> (compile '(lambda (x) (+ x x)) #:to 'assembly)
|
||||
(load-program 0 0 0
|
||||
() ; Labels
|
||||
70 ; Length
|
||||
#f ; Metadata
|
||||
(make-false)
|
||||
(make-false) ; object table for the returned lambda
|
||||
(nop)
|
||||
(nop) ; Alignment. Since assembly has already resolved its labels
|
||||
(nop) ; to offsets, and programs must be 8-byte aligned since their
|
||||
(nop) ; object code is mmap'd directly to structures, assembly
|
||||
(nop) ; has to have the alignment embedded in it.
|
||||
(nop)
|
||||
scheme@@(guile-user)> (compile '(+ 32 10) #:to 'assembly)
|
||||
(load-program
|
||||
1
|
||||
0
|
||||
((:LCASE104 . 6)) ; Labels, unused in this case.
|
||||
16 ; Length of the thunk that was compiled.
|
||||
(load-program ; Metadata thunk.
|
||||
()
|
||||
8
|
||||
(load-program 0 0 0 () 21 #f
|
||||
(load-symbol "x") ; Name and liveness extent for @code{x}.
|
||||
(make-false)
|
||||
(make-int8:0) ; Some instruction+arg combinations
|
||||
(make-int8:0) ; have abbreviations.
|
||||
(make-int8 6)
|
||||
(list 0 5)
|
||||
(list 0 1)
|
||||
17
|
||||
#f ; No metadata thunk for the metadata thunk.
|
||||
(make-eol)
|
||||
(list 0 2)
|
||||
(make-eol)
|
||||
(make-int8 6)
|
||||
(make-int8 12) ; Liveness extents, source info, and arities,
|
||||
(make-int8:0) ; in a format that Guile knows how to parse.
|
||||
(list 0 3)
|
||||
(list 0 1)
|
||||
(list 0 3)
|
||||
(return))
|
||||
; And here, the actual code.
|
||||
(local-ref 0)
|
||||
(local-ref 0)
|
||||
(assert-nargs-ee 0 0) ; Prologue.
|
||||
(reserve-locals 0 0)
|
||||
(make-int8 32) ; Actual code starts here.
|
||||
(make-int8 10)
|
||||
(add)
|
||||
(return)
|
||||
(nop)
|
||||
(nop) ; Padding; the metadata thunk is actually
|
||||
(nop) ; written after the main text.
|
||||
(nop))
|
||||
; Return our new procedure.
|
||||
(return))
|
||||
@end example
|
||||
|
||||
Of course you can switch the REPL to assembly and enter in assembly
|
||||
|
|
@ -679,11 +753,13 @@ structuring and destructuring code on the Scheme level. Bytecode is
|
|||
the next step down from assembly:
|
||||
|
||||
@example
|
||||
scheme@@(guile-user)> (compile '(+ 32 10) #:to 'assembly)
|
||||
@result{} (load-program 0 0 0 () 6 #f
|
||||
(make-int8 32) (make-int8 10) (add) (return))
|
||||
scheme@@(guile-user)> (compile '(+ 32 10) #:to 'bytecode)
|
||||
@result{} #u8(0 0 0 0 6 0 0 0 0 0 0 0 0 0 0 0 10 32 10 10 120 52)
|
||||
@result{} #vu8(16 0 0 0 25 0 0 0 ; Header.
|
||||
45 0 0 52 0 0 ; Prologue.
|
||||
10 32 10 10 148 66 ; Actual code.
|
||||
0 0 0 0 ; Padding.
|
||||
17 0 0 0 0 0 0 0 9 9 10 6 10 ; Metadata thunk.
|
||||
12 11 18 0 3 18 0 1 18 0 3 66)
|
||||
@end example
|
||||
|
||||
``Objcode'' is bytecode, but mapped directly to a C structure,
|
||||
|
|
@ -691,9 +767,6 @@ scheme@@(guile-user)> (compile '(+ 32 10) #:to 'bytecode)
|
|||
|
||||
@example
|
||||
struct scm_objcode @{
|
||||
scm_t_uint8 nargs;
|
||||
scm_t_uint8 nrest;
|
||||
scm_t_uint16 nlocs;
|
||||
scm_t_uint32 len;
|
||||
scm_t_uint32 metalen;
|
||||
scm_t_uint8 base[0];
|
||||
|
|
@ -701,9 +774,8 @@ struct scm_objcode @{
|
|||
@end example
|
||||
|
||||
As one might imagine, objcode imposes a minimum length on the
|
||||
bytecode. Also, the multibyte fields are in native endianness, which
|
||||
makes objcode (and bytecode) system-dependent. Indeed, in the short
|
||||
example above, all but the last 6 bytes were the program's header.
|
||||
bytecode. Also, the @code{len} and @code{metalen} fields are in native
|
||||
endianness, which makes objcode (and bytecode) system-dependent.
|
||||
|
||||
Objcode also has a couple of important efficiency hacks. First,
|
||||
objcode may be mapped directly from disk, allowing compiled code to be
|
||||
|
|
@ -725,7 +797,7 @@ Returns @code{#f} iff @var{obj} is object code, @code{#f} otherwise.
|
|||
@deffn {Scheme Procedure} bytecode->objcode bytecode
|
||||
@deffnx {C Function} scm_bytecode_to_objcode (bytecode)
|
||||
Makes a bytecode object from @var{bytecode}, which should be a
|
||||
@code{u8vector}.
|
||||
bytevector. @xref{Bytevectors}.
|
||||
@end deffn
|
||||
|
||||
@deffn {Scheme Variable} load-objcode file
|
||||
|
|
@ -739,12 +811,12 @@ prevent accidental loading of arbitrary garbage.
|
|||
|
||||
@deffn {Scheme Variable} write-objcode objcode file
|
||||
@deffnx {C Function} scm_write_objcode (objcode)
|
||||
Write object code out to a file, prepending the eight-byte cookie.
|
||||
Write object code out to a file, prepending the sixteen-byte cookie.
|
||||
@end deffn
|
||||
|
||||
@deffn {Scheme Variable} objcode->u8vector objcode
|
||||
@deffnx {C Function} scm_objcode_to_u8vector (objcode)
|
||||
Copy object code out to a @code{u8vector} for analysis by Scheme.
|
||||
@deffn {Scheme Variable} objcode->bytecode objcode
|
||||
@deffnx {C Function} scm_objcode_to_bytecode (objcode)
|
||||
Copy object code out to a bytevector for analysis by Scheme.
|
||||
@end deffn
|
||||
|
||||
The following procedure is actually in @code{(system vm program)}, but
|
||||
|
|
@ -766,13 +838,8 @@ Compiling object code to the fake language, @code{value}, is performed
|
|||
via loading objcode into a program, then executing that thunk with
|
||||
respect to the compilation environment. Normally the environment
|
||||
propagates through the compiler transparently, but users may specify
|
||||
the compilation environment manually as well:
|
||||
the compilation environment manually as well, as a module.
|
||||
|
||||
@deffn {Scheme Procedure} make-objcode-env module free-vars
|
||||
Make an object code environment. @var{module} should be a Scheme
|
||||
module, and @var{free-vars} should be a vector of free variables.
|
||||
@code{#f} is also a valid object code environment.
|
||||
@end deffn
|
||||
|
||||
@node Writing New High-Level Languages
|
||||
@subsection Writing New High-Level Languages
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue