-// PIC Port Peep rules
-//
-//
-// INTRODUCTION:
-//
-// The peep hole optimizer searchs the
-// the SDCC generated code for small snippets
-// that can be optimized. As a user, you have
-// control over this optimization process without
-// having to learn the SDCC source code. (However
-// you'll still need access to the source since
-// these rules are compiled into the source.)
-//
-// The way it works is you specify the target
-// snippet that you want replaced with a more
-// efficient snippet that you write. Wild card
-// variables allow the rules to be parameterized.
-//
-// In all of the SDCC ports, labels and operands
-// can be wild cards. However, in the PIC even the
-// instructions can be wild cards.
-//
-// EXAMPLE:
-//
-// Consider Peep Rule 1 as an example. This rule
-// replaces some code like:
-//
-// skpz ;i.e. btfss status,Z
-// goto lab1
-// clrw
-//lab1:
-//
-// with:
-//
-// skpnz ;i.e. btfsc status,Z
-// clrw
-//lab1
-//
-// However, the Rule has four wild cards.
-// The first allows the btfss instruction operator
-// be anything, not just the Z bit in status register.
-// The second wild card applies to a label.
-// The third wild card is for an instruction - any
-// single instruction can be substituted.
-// The fourth wild card is also an instruction. It's
-// just an instruction place holder associated with
-// a label (think of it as the PIC Port author's laziness
-// imposed upon the user).
-//
-//
-// CONDITIONS
-//
-// There are certain instances where a peep rule may not
-// be applicable. Consider this subtle example:
-//
-// movwf R0
-// movf R0,W
-//
-// It would seem that the second move is unnecessary. But
-// be careful! The movf instruction affects the 'Z' bit.
-// So if this sequence is followed by a btfsc status,Z, you
-// will have to leave the second move in.
-//
-// To get around this proble, the peep rule can be followed
-// by a conditon: "if NZ". Which is to say, apply the rule
-// if Z bit is not needed in the code that follows. The optimizer
-// is smart enough to look more than one instruction past the
-// target block...
-//
-// Special commands
-//
-//
-// _NOTBITSKIP_ %1 - Creates a wild card instruction that
-// will match all instructions except for
-// bit skip instructions (btfsc or btfss)
-// _BITSKIP_ %1 - Creates a wild card instruction that only
-// will match a bit skip instruction (btfsc
-// or btfss)
-// _INVERTBITSKIP_ %1 - For the wild card instruction %1, invert
-// the state of the bit skip. If %1 is not
-// a bit skip instruction, then there's an
-// error in the peep rule.
-//
-//
-//
-
-
-// Peep 1
-// Converts
-//
-// btfss reg1,bit
-// goto label
-// incf reg2,f
-//label
-//
-// Into:
-//
-// btfsc reg1,bit
-// incf reg2,f
-//label
-//
-// Notice that wild cards will allow any instruction
-// besides incf to be used in the above.
-//
-// Also, notice that this snippet is not valid if
-// it follows another skip
-
-
-replace restart {
- _NOTBITSKIP_ %1
- _BITSKIP_ %2
- goto %3
- %4
-%3: %5
-} by {
- ; peep 1 - test/jump to test/skip
- %1
- _INVERTBITSKIP_ %2
- %4
-%3: %5
-}
-
-replace restart {
- _NOTBITSKIP_ %1
- _BITSKIP_ %2
- goto %3
-%4: %5
-%3: %6
-} by {
- ; peep 1b - test/jump to test/skip
- %1
- _INVERTBITSKIP_ %2
-%4: %5
-%3: %6
-}
-
-
-//bogus test for pcode
-//replace restart {
-// movf %1,w ;comment at end
-//%4: movf %1,w
-// RETURN
-// clrf INDF0
-// movlw 0xa5
-// movf fsr0,w
-// incf indf0,f
-// %2
-//} by {
-// ; peep test remove redundant move
-//%4: movf %1,w ;another comment
-// %2
-//} if AYBABTU %3
-
-
-// peep 2
-replace restart {
- movwf %1
- movf %1,w
-} by {
- ; peep 2 - Removed redundant move
- movwf %1
-} if NZ
-
-// peep 3
-//replace restart {
-/ decf %1,f
-/// movf %1,w
-// btfss _STATUS,z
-// goto %2
-//} by {
-// ; peep 3 - decf/mov/skpz to decfsz
-// decfsz %1,f
-// goto %2
-//}
-
-
-replace restart {
- movf %1,w
- movf %1,w
-} by {
- ; peep 4 - Removed redundant move
- movf %1,w
-}
-
-
-replace restart {
- movlw %1
- movwf %2
- movlw %1
-} by {
- ; peep 5 - Removed redundant move
- movlw %1
- movwf %2
-}
-
-replace restart {
- movwf %1
- movwf %1
-} by {
- ; peep 6 - Removed redundant move
- movwf %1
-}
-
-replace restart {
- movlw 0
- iorwf %1,w
-} by {
- ; peep 7 - Removed redundant move
- movf %1,w
-}
-
-replace restart {
- movf %1,w
- movwf %2
- decf %2,f
-} by {
- ; peep 8 - Removed redundant move
- decf %1,w
- movwf %2
-}
-
-replace restart {
- movwf %1
- movf %2,w
- xorwf %1,w
-} by {
- ; peep 9a - Removed redundant move
- movwf %1
- xorwf %2,w
-}
-
-replace restart {
- movwf %1
- movf %2,w
- iorwf %1,w
-} by {
- ; peep 9b - Removed redundant move
- movwf %1
- iorwf %2,w
-}
-
-replace restart {
- movf %1,w
- movwf %2
- movf %2,w
-} by {
- ; peep 9c - Removed redundant move
- movf %1,w
- movwf %2
-}
-
-replace restart {
- movwf %1
- movf %1,w
- movwf %2
-} by {
- ; peep 9d - Removed redundant move
- movwf %1
- movwf %2
-} if NZ
-
-// From: Frieder Ferlemann
-
-replace restart {
- iorlw 0
-} by {
- ; peep 10a - Removed unnecessary iorlw
-} if NZ
-
-// From: Frieder Ferlemann
-
-replace restart {
- xorlw 0
-} by {
- ; peep 10b - Removed unnecessary xorlw
-} if NZ
-
-// From: Frieder Ferlemann
-
-replace restart {
- movf %1,w
- movwf %1
-} by {
- ; peep 11 - Removed redundant move
- movf %1,w
-}
-
-
-// From: Vangelis Rokas (vrokas AT otenet dot gr)
-// movff peeps are disabled for the moment
-// until support is added in the pcodepeeph.c
-
-//replace {
-// movf %1,w
-// movwf %2
-//} by {
-// ; peep 12 - Use movff to move source to dest
-// movff %1, %2
-//}
-
-//replace restart {
-// banksel %1
-// banksel %2
-//} by {
-// ; peep 13 - remove redudant banksel directive
-// banksel %2
-//}
-
-//replace restart {
-// movff %1,%2
-// movf %1,w
-//} by {
-// ; peep 14a - movff/movf is 6 bytes long, movfw/movwf is 4
-// movf %1,w
-// movwf %2
-//}
-
-//replace restart {
-// movff %1,%2
-// movff %1,%3
-//} by {
-// ; peep 14b - movff/movff is 8 bytes long movf/mowf/movwf is 6
-// movf %1,w
-// movwf %2
-// movwf %3
-//}
-
-//replace {
-// movff %1,%2
-//} by {
-// ; peep xxx - test peep to see if peep rules can handle movff
-// movf %1,w
-// movwf %2
-//}
projects / fw / sdcc / blobdiff