From 7223b8c63735e6a19b685970d1faff248ec307c1 Mon Sep 17 00:00:00 2001
From: slava <slava@factorcode.org>
Date: Thu, 27 Jul 2006 22:21:49 +0000
Subject: [PATCH] Minor inference cleanups

---
 TODO.FACTOR.txt                             |  6 +++---
 library/compiler/inference/branches.factor  | 20 ++++++++------------
 library/compiler/inference/inference.factor | 18 +++++++++---------
 3 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/TODO.FACTOR.txt b/TODO.FACTOR.txt
index 33f0ec8a39..1f34cfd271 100644
--- a/TODO.FACTOR.txt
+++ b/TODO.FACTOR.txt
@@ -1,5 +1,8 @@
 + 0.83:
 
+- nasty inference regressions
+- [ [ dup call ] dup call ] infer hangs
+- the invalid recursion form case needs to be fixed, for inlines too
 - windows port from erg
 - editor:
   - scroll to caret
@@ -100,7 +103,6 @@
 
 + compiler/ffi:
 
-- nasty inference regressions
 - instead of decompiling words, add them to a 'recompile' set; compiler
   treats words in the recompile set as if they were not compiled
 - mac intel: struct returns from objc methods
@@ -115,8 +117,6 @@
 - intrinsic fixnum>float float>fixnum
 - remove literal table
 - C functions returning structs by value
-- [ [ dup call ] dup call ] infer hangs
-- the invalid recursion form case needs to be fixed, for inlines too
 - code gc
 - infer which variables are read, written in a quotation
 
diff --git a/library/compiler/inference/branches.factor b/library/compiler/inference/branches.factor
index b71a4d9ddf..5d01a2ed5e 100644
--- a/library/compiler/inference/branches.factor
+++ b/library/compiler/inference/branches.factor
@@ -1,17 +1,14 @@
-! Copyright (C) 2004, 2005 Slava Pestov.
-! See http://factor.sf.net/license.txt for BSD license.
+! Copyright (C) 2004, 2006 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
 IN: inference
 USING: arrays errors generic hashtables interpreter kernel math
 namespaces parser prettyprint sequences strings vectors words ;
 
-: add-inputs ( n stack -- stack )
-    tuck length - dup 0 >
-    [ value-vector dup rot nappend ] [ drop ] if ;
-
 : unify-lengths ( seq -- seq )
     #! Pad all vectors to the same length. If one vector is
     #! shorter, pad it with unknown results at the bottom.
-    dup 0 [ length max ] reduce swap [ add-inputs ] map-with ;
+    dup 0 [ length max ] reduce
+    swap [ add-inputs nip ] map-with ;
 
 : unify-values ( seq -- value )
     #! If all values in list are equal, return the value.
@@ -34,9 +31,8 @@ namespaces parser prettyprint sequences strings vectors words ;
     0 [ [ max ] when* ] reduce ;
 
 : unbalanced-branches ( in out -- )
-    { "Unbalanced branches:" } -rot [
-        swap unparse " " rot length unparse append3
-    ] 2map append "\n" join inference-error ;
+    [ swap unparse " " rot length unparse append3 ] 2map
+    "Unbalanced branches:" add* "\n" join inference-error ;
 
 : unify-effect ( in out -- in out )
     #! In is a sequence of integers; out is a sequence of stacks.
@@ -52,7 +48,7 @@ namespaces parser prettyprint sequences strings vectors words ;
     ] map-with ;
 
 : datastack-effect ( seq -- )
-    dup d-in active-variable
+    d-in over [ hash ] map-with
     swap meta-d active-variable
     unify-effect meta-d set d-in set ;
 
@@ -66,7 +62,7 @@ namespaces parser prettyprint sequences strings vectors words ;
     [ terminated? swap hash ] all? terminated? set ;
 
 : unify-dataflow ( effects -- nodes )
-    [ [ dataflow-graph get ] bind ] map ;
+    [ dataflow-graph swap hash ] map ;
 
 : copy-inference ( -- )
     meta-r [ clone ] change
diff --git a/library/compiler/inference/inference.factor b/library/compiler/inference/inference.factor
index c2aaf33686..9faaddf707 100644
--- a/library/compiler/inference/inference.factor
+++ b/library/compiler/inference/inference.factor
@@ -1,5 +1,5 @@
-! Copyright (C) 2004, 2005 Slava Pestov.
-! See http://factor.sf.net/license.txt for BSD license.
+! Copyright (C) 2004, 2006 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
 IN: inference
 USING: arrays errors generic inspector interpreter io kernel
 math namespaces parser prettyprint sequences strings
@@ -30,7 +30,7 @@ M: object value-literal ( value -- )
 ! - infer - quotation with custom inference behavior; 'if' uses
 ! this. Word is passed on the stack.
 
-! Vector of results we had to add to the datastack. Ie, the
+! Number of values we had to add to the datastack. Ie, the
 ! inputs.
 SYMBOL: d-in
 
@@ -40,13 +40,13 @@ SYMBOL: d-in
 
 : value-vector ( n -- vector ) [ drop <computed> ] map >vector ;
 
+: add-inputs ( n stack -- n stack )
+    tuck length - dup 0 >
+    [ dup value-vector [ rot nappend ] keep ]
+    [ drop 0 swap ] if ;
+
 : ensure-values ( n -- )
-    meta-d get length 2dup > [
-        - dup d-in [ + ] change
-        value-vector meta-d [ dupd nappend ] change 
-    ] [
-        2drop
-    ] if ;
+    meta-d [ add-inputs ] change d-in [ + ] change ;
 
 : effect ( -- { in# out# } )
     #! After inference is finished, collect information.