factor: trim using lists

[factor.git] / extra / compiler / cfg / gvn / gvn.factor

diff --git a/extra/compiler/cfg/gvn/gvn.factor b/extra/compiler/cfg/gvn/gvn.factor
index 9c648d6125704f6cc2695d0e8ac5d709b911a10c..a1c77878a9a762a6aa7bb9251a884abbfc48d32c 100644 (file)
--- a/extra/compiler/cfg/gvn/gvn.factor
+++ b/extra/compiler/cfg/gvn/gvn.factor
@@ -1,38 +1,29 @@
-! Copyright (C) 2008, 2010 Slava Pestov.
+! Copyright (C) 2008, 2010 Slava Pestov, 2011 Alex Vondrak
 ! See http://factorcode.org/license.txt for BSD license.
-USING: namespaces arrays assocs hashtables kernel accessors fry
-grouping sorting sets sequences locals
-cpu.architecture
-sequences.deep
-compiler.cfg
-compiler.cfg.rpo
-compiler.cfg.def-use
-compiler.cfg.utilities
-compiler.cfg.instructions
-compiler.cfg.predecessors
-compiler.cfg.gvn.alien
-compiler.cfg.gvn.avail
-compiler.cfg.gvn.comparisons
-compiler.cfg.gvn.graph
-compiler.cfg.gvn.math
-compiler.cfg.gvn.rewrite
-compiler.cfg.gvn.slots
-compiler.cfg.gvn.misc
-compiler.cfg.gvn.expressions ;
+USING: accessors arrays assocs compiler.cfg compiler.cfg.def-use
+compiler.cfg.gvn.avail compiler.cfg.gvn.expressions
+compiler.cfg.gvn.graph compiler.cfg.gvn.rewrite
+compiler.cfg.instructions compiler.cfg.predecessors
+compiler.cfg.rpo compiler.cfg.utilities grouping kernel
+namespaces sequences sequences.deep ;
 IN: compiler.cfg.gvn
 
 GENERIC: simplify ( insn -- insn' )
 
-M: insn simplify dup rewrite [ simplify ] [ ] ?if ;
+M: insn simplify dup rewrite [ simplify ] [ dup >avail-insn-uses ] ?if ;
 M: array simplify [ simplify ] map ;
 M: ##copy simplify ;
 
+! ! ! Global value numbering
+
 GENERIC: value-number ( insn -- )
 
 M: array value-number [ value-number ] each ;
 
-M: alien-call-insn value-number drop ;
-M: ##callback-inputs value-number drop ;
+: record-defs ( insn -- ) defs-vregs [ dup set-vn ] each ;
+
+M: alien-call-insn value-number record-defs ;
+M: ##callback-inputs value-number record-defs ;
 
 M: ##copy value-number [ src>> vreg>vn ] [ dst>> ] bi set-vn ;
 
@@ -73,8 +64,51 @@ M: insn value-number
         changed? get
     ] loop ;
 
-: value-numbering ( cfg -- cfg )
-    needs-predecessors
-    dup determine-value-numbers
+! ! ! Global common subexpression elimination
+
+GENERIC: gcse ( insn -- insn' )
+
+M: array gcse [ gcse ] map ;
+
+: defs-available ( insn -- insn )
+    dup defs-vregs [ make-available ] each ;
 
-    cfg-changed predecessors-changed ;
+M: alien-call-insn gcse defs-available ;
+M: ##callback-inputs gcse defs-available ;
+M: ##copy gcse defs-available ;
+
+: ?eliminate ( insn vn -- insn' )
+    dup available? [
+        [ dst>> dup make-available ] dip <copy>
+    ] [ drop defs-available ] if ;
+
+: eliminate-redundancy ( insn -- insn' )
+    dup >expr exprs>vns get at >avail-vreg
+    [ ?eliminate ] [ defs-available ] if* ;
+
+M: ##phi gcse
+    dup inputs>> values [ vreg>vn ] map sift
+    dup all-equal? [
+        [ first ?eliminate ] unless-empty
+    ] [ drop eliminate-redundancy ] if ;
+
+M: insn gcse
+    dup defs-vregs length 1 = [ eliminate-redundancy ] when ;
+
+: gcse-step ( insns -- insns' )
+    [ simplify gcse ] map flatten ;
+
+: eliminate-common-subexpressions ( cfg -- )
+    final-iteration? on
+    compute-congruence-classes
+    dup compute-avail-sets
+    [ gcse-step ] simple-optimization ;
+
+: value-numbering ( cfg -- )
+    {
+        needs-predecessors
+        determine-value-numbers
+        eliminate-common-subexpressions
+        cfg-changed
+        predecessors-changed
+    } apply-passes ;