// peeph.def - Common Z80 and gbz80 peephole rules
-//
-//
-// (c) Philipp Klaus Krause (pkk@spth.de, philipp@colecovision.eu) 2006 - 2007
-//
-// This program is free software; you can redistribute it and/or modify it
-// under the terms of the GNU General Public License as published by the
-// Free Software Foundation; either version 2, or (at your option) any
-// later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU General Public License for more details.
-//
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
-replace restart {
- ld %1,%1
-} by {
- ; peephole 1 removed redundant load.
-} if notVolatile(%1)
-
-replace restart {
- ld %1,%3
- ld %1,%2
-} by {
- ; peephole 2 removed dead load into %1
- ld %1,%2
-} if notVolatile(%1 %3), operandsNotSame
-
-replace restart {
- jp NC,%1
- jp %2
-%1:
-} by {
- jp C,%2
- ; peephole 3 removed jp by using inverse jump logic
-%1:
-} if labelRefCountChange(%1 -1)
-
-replace restart {
- jp C,%1
- jp %2
-%1:
-} by {
- jp NC,%2
- ; peephole 4 removed jp by using inverse jump logic
-%1:
-} if labelRefCountChange(%1 -1)
-
-replace restart {
- jp NZ,%1
- jp %2
-%1:
-} by {
- jp Z,%2
- ; peephole 5 removed jp by using inverse jump logic
-%1:
-} if labelRefCountChange(%1 -1)
-
-replace restart {
- jp Z,%1
- jp %2
-%1:
-} by {
- jp NZ,%2
- ; peephole 6 removed jp by using inverse jump logic
-%1:
-} if labelRefCountChange(%1 -1)
-
-replace restart {
- jp %5
-} by {
- jp %6
- ; peephole 7 redirected jump-to-jump at %5 by jump to %6
-} if labelIsUncondJump(), labelRefCountChange(%5 -1), labelRefCountChange(%6 +1)
-
-replace restart {
- jp %1,%5
-} by {
- jp %1,%6
- ; peephole 8 redirected jump-to-jump at %5 by jump to %6
-} if labelIsUncondJump(), labelRefCountChange(%5 -1), labelRefCountChange(%6 +1)
-
-replace restart {
- ld %2,%3
- jp %4
-%5:
- ld %2,%3
-%4:
-} by {
- ; peephole 9 removed jump and redundant load.
-%5:
- ld %2,%3
-%4:
-} if labelRefCountChange(%4 -1)
-
-replace restart {
- xor a,a
- ld a,#0x00
-} by {
- xor a,a
- ; peephole 10 removed redundant load of 0 into a.
-}
-
-replace {
- ld e,#0x%1
- ld d,#0x%2
-} by {
- ld de,#0x%2%1
- ; peephole 11 combined constant loads into register pair.
-}
-
-replace {
- ld l,#0x%1
- ld h,#0x%2
-} by {
- ld hl,#0x%2%1
- ; peephole 12 combined constant loads into register pair.
-}
-
-replace {
- ld c,#0x%1
- ld b,#0x%2
-} by {
- ld bc,#0x%2%1
- ; peephole 13 combined constant loads into register pair.
-}
-
-replace restart {
- ld %1,a
- ld a,%1
-} by {
- ld %1,a
- ; peephole 14 removed redundant load from %1 into a.
-} if notVolatile(%1)
-// This gives many false negatives and without the test no problems are encountered in the regression tests
-// Maybe we can try this after 2.7.0 release
-
-replace restart {
- ld a,%1
- ld %1,a
-} by {
- ld a,%1
- ; peephole 15 removed redundant load from a into %1.
-} if notVolatile(%1)
-// This gives many false negatives and without the test no problems are encountered in the regression tests
-// Maybe we can try this after 2.7.0 release
-
-replace restart {
- ld %2,%3
- ld a,%2
- and a,%1
- ld %2,%4
-} by {
- ld a,%3
- ; peephole 16 moved %3 directly into a instead of going through %2.
- and a,%1
- ld %2,%4
-} if notVolatile(%2), operandsNotSame
-
-replace restart {
- ld %1,a
- ld a,%2
- or a,%1
-} by {
- ld %1,a
- or a,%2
- ; peephole 17 removed load by reordering or arguments.
-} if notVolatile(%1)
-
-replace restart {
- ld %1,a
- xor a,a
- or a,%1
-} by {
- ld %1,a
- or a,a
- ; peephole 18 used value still in a instead of loading it from %1.
-}
-
-replace restart {
- or a,%1
- or a,a
-} by {
- or a,%1
- ; peephole 19 removed redundant or after or.
-}
-
-replace restart {
- and a,%1
- or a,a
-} by {
- and a,%1
- ; peephole 20 removed redundant or after and.
-}
-
-replace restart {
- xor a,%1
- or a,a
-} by {
- xor a,%1
- ; peephole 21 removed redundant or after xor.
-}
-
-replace restart {
- ld %1,a
- and a,%2
- ld %1,a
-} by {
- ; peephole 22 removed redundant load into %1.
- and a,%2
- ld %1,a
-} if notVolatile(%1)
-
-replace {
- ld %1,%2
- ld a,%2
-} by {
- ld a,%2
- ld %1,a
- ; peephole 23 load value in a first and use it next
-} if notVolatile(%1 %2)
-
-replace restart {
- ld %1,%2
- ld %3,%4
- ld %2,%1
- ld %4,%3
-} by {
- ld %1,%2
- ld %3,%4
- ; peephole 24 removed redundant load from %3%1 into %4%2
-} if notVolatile(%1 %2 %3 %4)
-
-replace restart {
- ld b,%1
- ld a,b
- pop bc
-} by {
- ld a,%1
- ; peephole 25 removed load into b
- pop bc
-}
-
-replace restart {
- ld c,%1
- ld a,c
- pop bc
-} by {
- ld a,%1
- ; peephole 26 removed load into c
- pop bc
-}
-
-replace restart {
- ld d,%1
- ld a,d
- pop de
-} by {
- ld a,%1
- ; peephole 27 removed load into d
- pop de
-}
-
-replace restart {
- ld e,%1
- ld a,e
- pop de
-} by {
- ld a,%1
- ; peephole 28 removed load into e
- pop de
-}
-
-replace restart {
- ld h,%1
- ld a,h
- pop hl
-} by {
- ld a,%1
- ; peephole 29 removed load into h
- pop hl
-}
-
-replace restart {
- ld l,%1
- ld a,l
- pop hl
-} by {
- ld a,%1
- ; peephole 30 removed load into l
- pop hl
-}
-
-replace restart {
- ld a,c
- push af
- inc sp
- ld a,#%2
- push af
- inc sp
- call %3
-} by {
- ld b,c
- ld c,#%2
- push bc
- ; peephole 31 moved and pushed arguments c and #%2 through bc instead of pushing them individually.
- call %3
-}
-
-replace restart {
- ld a,e
- push af
- inc sp
- ld a,#%2
- push af
- inc sp
- call %3
-} by {
- ld d,e
- ld e,#%2
- push de
- ; peephole 32 moved and pushed arguments e and #%2 through de instead of pushing them individually.
- call %3
-}
-
-replace restart {
- ld a,%1
- sub a,%2
- jp %3,%4
- ld a,%1
-} by {
- ld a,%1
- cp a,%2
- jp %3,%4
- ; peephole 33 removed load by replacing sub with cp
- assert a=%1
-} if notVolatile(%1)
-
-replace restart {
- assert a=%1
- sub a,%2
- jp %3,%4
- ld a,%1
-} by {
- cp a,#%2
- jp %3,%4
- ; peephole 34 removed load by replacing sub with cp
- assert a=%1
-}
-
-replace restart {
- assert a=%1
-} by {
-}
-
-replace restart {
- sub a,#0xFF
- jp Z,%1
-} by {
- inc a
- ; peephole 35 replaced sub a,#0xFF by inc a.
- jp Z,%1
-}
-
-replace restart {
- sub a,#0xFF
- jp NZ,%1
-} by {
- inc a
- ; peephole 36 replaced sub a,#0xFF by inc a.
- jp NZ,%1
-}
-
-replace restart {
- ld bc,#%1 + %2
- ld a,c
- add a,%3
- ld c,a
- ld a,b
- adc a,%4
- ld b,a
-} by {
- ld a,#<(%1 + %2)
- add a,%3
- ld c,a
- ld a,#>(%1 + %2)
- ; peephole 37 directly used (%1 + %2) in calculation instead of placing it in bc first.
- adc a,%4
- ld b,a
-}
-
-replace restart {
- ld de,#%1 + %2
- ld a,e
- add a,%3
- ld e,a
- ld a,d
- adc a,%4
- ld d,a
-} by {
- ld a,#<(%1 + %2)
- add a,%3
- ld e,a
- ld a,#>(%1 + %2)
- ; peephole 38 directly used (%1 + %2) in calculation instead of placing it in de first.
- adc a,%4
- ld d,a
-}
-
-replace restart {
- rlca
- ld a,#0x00
- rla
-} by {
- rlca
- and a,#0x01
- ; peephole 39 replaced zero load, rla by and since rlca writes the same value to carry bit and least significant bit.
-}
-
-replace restart {
- ld %1,%2
- push %1
- pop %4
- ld %1,%3
-} by {
- ld %4,%2
- ; peephole 40 moved %2 directly into de instead of going through %1.
- ld %1,%3
-}
-
-replace restart {
- add a,#0x00
- ld %2,a
- ld a,%3
- adc a,%4
-} by {
- ; peephole 41 removed lower part of multibyte addition.
- ld %2,a
- ld a,%3
- add a,%4
-}
-
-replace restart {
- ld %1,a
- ld a,%2
- add a,%1
- ld %1,a
-} by {
- ; peephole 42 removed loads by exploiting commutativity of addition.
- add a,%2
- ld %1,a
-} if notVolatile(%1)
-
-replace restart {
- ld %1,a
- ld a,%2
- add a,%1
-} by {
- ld %1, a
- ; peephole 43 removed load by exploiting commutativity of addition.
- add a,%2
-}
-
-replace restart {
- or a,%1
- jp NZ,%2
- xor a,a
- or a,%3
-} by {
- or a,%1
- jp NZ,%2
- ; peephole 44 removed redundant zeroing of a (which has just been tested to be #0x00).
- or a,%3
-}
-
-replace restart {
- or a,%1
- jp NZ,%2
- ld %3,#0x00
-} by {
- or a,%1
- jp NZ,%2
- ld %3,a
- ; peephole 45 replaced constant #0x00 by a (which has just been tested to be #0x00).
-}
-
-replace restart {
- and a,%1
- jp NZ,%2
- ld %3,#0x00
-} by {
- and a,%1
- jp NZ,%2
- ld %3,a
- ; peephole 46 replaced constant #0x00 by a (which has just been tested to be #0x00).
-}
-
-replace restart {
- sub a,%1
- jp NZ,%2
- ld %3,#0x00
-} by {
- sub a,%1
- jp NZ,%2
- ld %3,a
- ; peephole 47 replaced constant #0x00 by a (which has just been tested to be #0x00).
-}
-
-replace restart {
- dec a
- jp NZ,%1
- ld %2,#0x00
-} by {
- dec a
- jp NZ,%1
- ld %2,a
- ; peephole 48 replaced constant #0x00 by a (which has just been tested to be #0x00).
-}
-
-replace restart {
- or a,%1
- jp NZ,%2
- ld a,%3
- or a,a
-} by {
- or a,%1
- jp NZ,%2
- or a,%3
- ; peephole 49 shortened or using a (which has just been tested to be #0x00).
-}
-
-replace restart {
- and a,%1
- jp NZ,%2
- ld a,%3
- or a,a
-} by {
- and a,%1
- jp NZ,%2
- or a,%3
- ; peephole 50 shortened or using a (which has just been tested to be #0x00).
-}
-
-replace restart {
- sub a,%1
- jp NZ,%2
- ld a,%3
- or a,a
-} by {
- sub a,%1
- jp NZ,%2
- or a,%3
- ; peephole 51 shortened or using a (which has just been tested to be #0x00).
-}
-
-replace restart {
- dec a
- jp NZ,%1
- ld a,%2
- or a,a
-} by {
- dec a
- jp NZ,%1
- or a,%2
- ; peephole 52 shortened or using a (which has just been tested to be #0x00).
-}
-
-replace restart {
- or a,%1
- jp NZ,%2
- push %3
- ld %4,#0x00
-} by {
- or a,%1
- jp NZ,%2
- push %3
- ld %4,a
- ; peephole 53 replaced constant #0x00 by a (which has just been tested to be #0x00).
-}
-
-replace restart {
- and a,%1
- jp NZ,%2
- push %3
- ld %4,#0x00
-} by {
- sub a,%1
- jp NZ,%2
- push %3
- ld %4,a
- ; peephole 54 replaced constant #0x00 by a (which has just been tested to be #0x00).
-}
-
-replace restart {
- sub a,%1
- jp NZ,%2
- push %3
- ld %4,#0x00
-} by {
- sub a,%1
- jp NZ,%2
- push %3
- ld %4,a
- ; peephole 55 replaced constant #0x00 by a (which has just been tested to be #0x00).
-}
-
-replace restart {
- dec a
- jp NZ,%1
- push %2
- ld %3,#0x00
-} by {
- dec a
- jp NZ,%1
- push %2
- ld %3,a
- ; peephole 56 replaced constant #0x00 by a (which has just been tested to be #0x00).
-}
-
-replace restart {
- ld de,#%1 + %2
- inc de
- inc de
- inc de
-} by {
- ld de,#%1 + %2 + 3
- ; peephole 57 moved triple increment of de to constant.
-}
-
-replace restart {
- ld de,#%1 + %2
- inc de
- inc de
-} by {
- ld de,#%1 + %2 + 2
- ; peephole 58 moved double increment of de to constant.
-}
-
-replace restart {
- ld de,#%1 + %2
- inc de
-} by {
- ld de,#%1 + %2 + 1
- ; peephole 59 moved increment of de to constant.
-}
-
-replace restart {
- ld bc,#%1 + %2
- inc bc
- inc bc
- inc bc
-} by {
- ld bc,#%1 + %2 + 3
- ; peephole 60 moved triple increment of bc to constant.
-}
-
-replace restart {
- ld bc,#%1 + %2
- inc bc
- inc bc
-} by {
- ld bc,#%1 + %2 + 2
- ; peephole 61 moved double increment of bc to constant.
-}
-
-replace restart {
- ld bc,#%1 + %2
- inc bc
-} by {
- ld bc,#%1 + %2 + 1
- ; peephole 62 moved increment of bc to constant.
-}
-
-replace restart {
- ld bc,#%1
- ld a,c
- add a,#0x%2
- ld c,a
- ld a,b
- adc a,#0x%3
- ld b,a
-} by {
- ld bc,#%1 + 0x%3%2
- ; peephole 63 moved addition of constant 0x%3%2 to bc to constant.
-}
-
-replace restart {
- ld bc,#%1 + %4
- ld a,c
- add a,#0x%2
- ld c,a
- ld a,b
- adc a,#0x%3
- ld b,a
-} by {
- ld bc,#%1 + %4 + 0x%3%2
- ; peephole 64 moved addition of constant 0x%3%2 to bc to constant.
-}
+// This file should contain common Z80/GBZ80 peepholes.
+// However the GBZ80 port is currently unmaintained;
+// a GBZ80 expert could extract peepholes that are useful for both Z80 and GBZ80
+// from peeph-z80.def and peeph-gbz80.def and move them here.