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authorshyouhei <shyouhei@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2018-01-09 13:30:29 +0000
committershyouhei <shyouhei@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2018-01-09 13:30:29 +0000
commit310be7547df8ba20b6c511894b9c2d70f24da824 (patch)
tree3b9917126e8915198d10f17e13942baf1621287f /insns.def
parent89df12d849f4a7d2c78f61251b45fd4b94d41bc2 (diff)
[ci skip] add comments about file format
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61730 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'insns.def')
-rw-r--r--insns.def42
1 files changed, 38 insertions, 4 deletions
diff --git a/insns.def b/insns.def
index 7f72e9ec86..7d75f2a0ce 100644
--- a/insns.def
+++ b/insns.def
@@ -1,15 +1,49 @@
-/** ##skip -*- mode:c; style:ruby; coding: utf-8 -*-
+/* -*- mode:c; style:ruby; coding: utf-8 -*-
insns.def - YARV instruction definitions
$Author: $
created at: 04/01/01 01:17:55 JST
Copyright (C) 2004-2007 Koichi Sasada
+ Massive rewtite by @shyouhei in 2017.
*/
-/** ##skip
- instruction comment
- : english description
+/* Some comments about this file's contents:
+
+ - The new format aims to be editable by C editor of your choice;
+ your mileage might vary of course.
+
+ - Each instructions are in following format:
+
+ DEFINE_INSN
+ instruction_name
+ (type operand, type operand, ..)
+ (pop_values, ..)
+ (return values ..)
+ #pragma attr type name contents..
+ {
+ .. // insn body
+ }
+
+ - Unlike the old format which was line-oriented, you can now place
+ newlines and comments at liberal positions.
+
+ - `DEFINE_INSN` is a keyword.
+
+ - An instruction name must be a valid C identifier.
+
+ - Operands, pop values, return values are series of either variable
+ declarations, keyword `void`, or keyword `...`. They are much
+ like C function declarations.
+
+ - Attribute pragmas are optional, and can include arbitrary C
+ expressions. You can write anything there but as of writing,
+ attribute named sp_inc is supported.
+
+ - Attributes can access operands, but not stack (push/pop) variables.
+
+ - An instruction's body is a pure C block, copied verbatimly into
+ the generated C source code.
*/
/* nop */