1 ! Copyright (C) 2008 Slava Pestov.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: kernel sequences layouts accessors combinators namespaces
6 compiler.cfg.instructions
7 compiler.cfg.value-numbering.graph
8 compiler.cfg.value-numbering.simplify
9 compiler.cfg.value-numbering.expressions ;
10 IN: compiler.cfg.value-numbering.rewrite
12 GENERIC: rewrite ( insn -- insn' )
15 dup src2>> dup power-of-2? [
16 [ [ dst>> ] [ src1>> ] bi ] [ log2 ] bi* \ ##shl-imm new-insn
20 : ##branch-t? ( insn -- ? )
21 dup ##compare-imm-branch? [
23 [ src2>> \ f tag-number eq? ] bi and
24 ] [ drop f ] if ; inline
26 : rewrite-boolean-comparison? ( insn -- ? )
28 src1>> vreg>expr compare-expr?
29 ] [ drop f ] if ; inline
31 : >compare-expr< ( expr -- in1 in2 cc )
32 [ in1>> vn>vreg ] [ in2>> vn>vreg ] [ cc>> ] tri ; inline
34 : >compare-imm-expr< ( expr -- in1 in2 cc )
35 [ in1>> vn>vreg ] [ in2>> vn>constant ] [ cc>> ] tri ; inline
37 : rewrite-boolean-comparison ( expr -- insn )
38 src1>> vreg>expr dup op>> {
39 { \ ##compare [ >compare-expr< \ ##compare-branch new-insn ] }
40 { \ ##compare-imm [ >compare-imm-expr< \ ##compare-imm-branch new-insn ] }
41 { \ ##compare-float [ >compare-expr< \ ##compare-float-branch new-insn ] }
44 : tag-fixnum-expr? ( expr -- ? )
45 dup op>> \ ##shl-imm eq?
46 [ in2>> vn>constant tag-bits get = ] [ drop f ] if ;
48 : rewrite-tagged-comparison? ( insn -- ? )
49 #! Are we comparing two tagged fixnums? Then untag them.
50 [ src1>> vreg>expr tag-fixnum-expr? ]
51 [ src2>> tag-mask get bitand 0 = ]
54 : (rewrite-tagged-comparison) ( insn -- src1 src2 cc )
55 [ src1>> vreg>expr in1>> vn>vreg ]
56 [ src2>> tag-bits get neg shift ]
60 GENERIC: rewrite-tagged-comparison ( insn -- insn' )
62 M: ##compare-imm-branch rewrite-tagged-comparison
63 (rewrite-tagged-comparison) \ ##compare-imm-branch new-insn ;
65 M: ##compare-imm rewrite-tagged-comparison
66 [ dst>> ] [ (rewrite-tagged-comparison) ] bi
67 i \ ##compare-imm new-insn ;
69 M: ##compare-imm-branch rewrite
70 dup rewrite-boolean-comparison? [ rewrite-boolean-comparison ] when
71 dup ##compare-imm-branch? [
72 dup rewrite-tagged-comparison? [ rewrite-tagged-comparison ] when
75 : flip-comparison? ( insn -- ? )
76 dup cc>> cc= eq? [ src1>> vreg>expr constant-expr? ] [ drop f ] if ;
78 : flip-comparison ( insn -- insn' )
81 [ src1>> vreg>vn vn>constant ] tri
82 cc= i \ ##compare-imm new-insn ;
85 dup flip-comparison? [
91 : rewrite-redundant-comparison? ( insn -- ? )
92 [ src1>> vreg>expr compare-expr? ]
93 [ src2>> \ f tag-number = ]
94 [ cc>> { cc= cc/= } memq? ]
97 : rewrite-redundant-comparison ( insn -- insn' )
98 [ cc>> ] [ dst>> ] [ src1>> vreg>expr dup op>> ] tri {
99 { \ ##compare [ >compare-expr< i \ ##compare new-insn ] }
100 { \ ##compare-imm [ >compare-imm-expr< i \ ##compare-imm new-insn ] }
101 { \ ##compare-float [ >compare-expr< i \ ##compare-float new-insn ] }
103 swap cc= eq? [ [ negate-cc ] change-cc ] when ;
105 M: ##compare-imm rewrite
106 dup rewrite-redundant-comparison? [
107 rewrite-redundant-comparison
108 dup number-values rewrite
111 dup rewrite-tagged-comparison? [
112 rewrite-tagged-comparison
113 dup number-values rewrite