--- gforth/arch/alpha/asm.fs 1999/02/02 22:02:54 1.1 +++ gforth/arch/alpha/asm.fs 2000/06/17 19:38:28 1.5 @@ -1,10 +1,14 @@ + \ bernd thallner 9725890 881 \ assembler in forth for alpha -\ requires code.fs +\ require ../../code.fs +get-current also assembler definitions +\ register + $0 constant v0 $1 constant t0 $2 constant t1 @@ -21,12 +25,13 @@ also assembler definitions $d constant s4 $e constant s5 $f constant fp -$10 constant a0 -$11 constant a1 -$12 constant a2 -$13 constant a3 -$14 constant a4 -$15 constant a5 +\ commented out to avoid shadowing hex numbers +\ $10 constant a0 +\ $11 constant a1 +\ $12 constant a2 +\ $13 constant a3 +\ $14 constant a4 +\ $15 constant a5 $16 constant t8 $17 constant t9 $18 constant t10 @@ -38,18 +43,37 @@ $1d constant gp $1e constant sp $1f constant zero -: shift ( a n -- a<<=n ) -0 -?do - 2* -loop +\ util + +: h@ ( addr -- n ) \ 32 bit fetch +dup dup aligned = if + @ + $00000000ffffffff and +else + 4 - @ + $20 rshift +endif +; + +: h! ( n addr -- ) \ 32 bit store +dup dup aligned = if + dup @ + $ffffffff00000000 and + rot or + swap ! +else + 4 - dup @ + $00000000ffffffff and + rot $20 lshift or + swap ! +endif ; -: h, ( h -- ) \ 32 bit store +: h, ( h -- ) \ 32 bit store + allot here here aligned = if here ! else - 32 shift + 32 lshift here 4 - dup @ rot or swap ! @@ -57,88 +81,87 @@ endif 4 allot ; -: Bra ( oo ) \ branch instruction format - create , -does> ( ra, branch_disp, addr ) - @ 26 shift - swap $1fffff and or - swap $1f and 21 shift or h, -; - -: Mbr ( oo.h ) \ memory branch instruction format - create 2, -does> ( ra, rb, hint, addr ) - 2@ 14 shift - swap 26 shift or - swap $3fff and or - swap $1f and 16 shift or - swap $1f and 21 shift or - h, -; - -: F-P ( oo.fff ) \ floating-point operate instruction format - create 2, -does> ( fa, fb, fc, addr ) - 2@ 5 shift - swap 26 shift or - swap $1f and or - swap $1f and 16 shift or - swap $1f and 21 shift or - h, -; - -: Mem ( oo ) \ memory instruction format - create , -does> ( ra, memory_disp, rb, addr ) - @ 26 shift - swap $1f and 16 shift or - swap $ffff and or - swap $1f and 21 shift or - h, -; - -: Mfc ( oo.ffff ) \ memory instruction with function code format - create 2, -does> ( ra, rb, addr ) - 2@ - swap 26 shift or - swap $1f and 16 shift or - swap $1f and 21 shift or - h, -; - -: Opr ( oo.ff ) \ operate instruction format - create 2, -does> ( ra, rb, rc, addr ) - 2@ - 5 shift - swap 26 shift or - swap $1f and or - swap $1f and 16 shift or - swap $1f and 21 shift or - h, -; - -: Opr# ( oo.ff ) \ operate instruction format - create 2, -does> ( ra, lit, rc, addr ) - 2@ - 5 shift - swap 26 shift or - 1 12 shift or - swap $1f and or - swap $ff and 13 shift or - swap $1f and 21 shift or - h, -; - -: Pcd ( oo ) \ palcode instruction format - create , -does> ( palcode, addr ) - @ 26 shift - swap $3ffffff and or - h, -; +\ operands + +: check-range ( u1 u2 u3 -- ) + within 0= -24 and throw ; + +: rega ( rega code -- code ) + \ ra field, named rega to avoid conflict with register ra + swap dup 0 $20 check-range + 21 lshift or ; + +: rb ( rb code -- code ) + swap dup 0 $20 check-range + 16 lshift or ; + +: rc ( rc code -- code ) + swap dup 0 $20 check-range + or ; + +: hint ( addr code -- code ) + swap 2 rshift $3fff and or ; + +: disp ( n code -- code ) + swap dup -$8000 $8000 check-range + $ffff and or ; + +: branch-disp ( addr code -- code ) + swap here 4 + - + dup 3 and 0<> -24 and throw + dup -$100000 $100000 check-range + $1fffff and or ; + +: imm ( u code -- code ) + swap dup 0 $100 check-range + 13 lshift or ; + +: palcode ( u code -- code ) + swap dup 0 $4000000 check-range or ; + +\ formats + +: Bra ( opcode -- ) \ branch instruction format + create 26 lshift , +does> ( rega target-addr -- ) + @ branch-disp rega h, ; + +: Mbr ( opcode hint -- ) \ memory branch instruction format + create 14 lshift swap 26 lshift or , +does> ( rega rb hint -- ) + @ hint rb rega h, ; + +: F-P ( opcode func -- ) \ floating-point operate instruction format + create 5 lshift swap 26 lshift or , +does> ( fa fb fc -- ) + @ rc rb rega h, ; + +: Mem ( opcode -- ) \ memory instruction format + create 26 lshift , +does> ( rega memory_disp rb -- ) + @ rb disp rega h, ; + +: Mfc ( opcode func -- ) \ memory instruction with function code format + create swap 26 lshift or , +does> ( rega rb -- ) + @ rb rega h, ; + +: Opr ( opcode.ff ) \ operate instruction format + create 5 lshift swap 26 lshift or , +does> ( rega rb rc -- ) + @ rc rb rega h, ; + +: Opr# ( opcode func -- ) \ operate instruction format + create 5 lshift swap 26 lshift or 1 12 lshift or , +does> ( rega imm rc -- ) + @ rc imm rega h, ; + +: Pcd ( opcode -- ) \ palcode instruction format + create 26 lshift , +does> ( palcode addr -- ) + @ palcode h, ; + +\ instructions $15 $80 F-P addf, $15 $a0 F-P addg, @@ -165,7 +188,7 @@ $38 Bra blbc, $3c Bra blbs, $3b Bra ble, $3a Bra blt, -$3d Bra bne, +$3d Bra bne, $30 Bra br, $34 Bra bsr, $00 Pcd call_pal, @@ -374,3 +397,195 @@ $12 $30 Opr# zap#, $12 $31 Opr zapnot, $12 $31 Opr# zapnot#, +\ conditions + +' beq, constant ne +' bge, constant lt +' bgt, constant le +' blbc, constant lbs +' blbs, constant lbc +' ble, constant gt +' blt, constant ge +' bne, constant eq +' fbeq, constant fne +' fbge, constant flt +' fbgt, constant fle +' fble, constant fgt +' fblt, constant fge +' fbne, constant feq + +\ control structures + +\ if, [ else, ] endif, + +\ : magic-asm ( u1 u2 -- u3 u4 ) +\ \ turns a magic number into an asm-magic number or back +\ $fedcba0987654321 xor ; + +\ : patch-branch ( branch-delay-addr target-addr -- ) +\ \ there is a branch just before branch-delay-addr; PATCH-BRANCH +\ \ patches this branch to branch to target-addr +\ over - ( branch-delay-addr rel ) +\ swap cell - dup >r ( rel branch-addr R:branch-addr ) +\ @ asm-rel r> ! ; \ !! relies on the imm field being 0 before + + + +: ahead, ( -- asmorig ) + 31 0 br, + here 4 - +; + +: if, ( -- asmorig ) + 0 beq, + here 4 - +; + +: endif, ( asmorig -- ) + dup here swap - 4 - 4 / + $1fffff and + over h@ or swap h! +; + +: else, ( asmorig1 -- asmorig2 ) + ahead, + swap + endif, +; + +\ begin, again, + +: begin, ( -- asmdest ) + here +; + +: again, ( asmdest -- ) + here - 4 - 4 / + $1fffff and + 31 swap br, +; + +\ begin, until, + +: until, ( asmdest -- ) + here rot swap - 4 - 4 / + $1fffff and + bne, +; + +\ begin, while, repeat, + +: while, ( asmdest -- asmorig asmdest ) + if, + swap +; + +: repeat, ( asmorig asmdest -- ) + again, + endif, +; + +\ \ jump marks + +\ \ example: + +\ \ init_marktbl \ initializes mark table +\ \ 31 0 br, +\ \ 0 store_branch \ store jump address for mark 0 +\ \ 1 2 3 addf, +\ \ 0 set_mark \ store mark 0 +\ \ 2 3 4 addf, +\ \ 2 0 beq, +\ \ 0 store_branch \ store jump address for mark 0 +\ \ calculate_marks \ calculate all jumps + +\ \ with calculate_branch you can calculate the +\ \ displacement field without the mark_table for one branch + +\ \ example: +\ \ here 31 0 br, +\ \ here 1 2 3 addf, +\ \ calculate_branch + +\ 5 constant mark_numbers +\ 5 constant mark_uses + +\ create mark_table +\ mark_numbers mark_uses 1+ * cells allot + +\ : init_marktbl ( -- ) \ initializes mark table +\ mark_table mark_numbers mark_uses 1+ * cells + +\ mark_table +\ begin +\ over over > +\ while +\ dup 0 swap ! +\ 1 cells + +\ repeat +\ drop drop +\ ; + +\ : set_mark ( mark_number -- ) \ sets mark, store address in mark table +\ dup mark_numbers >= abort" error, illegal mark number" +\ mark_uses 1+ * cells +\ mark_table + here 8 - swap ! +\ ; + +\ : store_branch ( mark_number -- ) \ stores address of branch in mark table +\ dup mark_numbers >= abort" error, illegal mark number" +\ mark_uses 1+ * cells +\ mark_table + 1 cells + +\ dup mark_uses cells + swap +\ begin +\ over over > over @ and +\ while +\ 1 cells + +\ repeat +\ swap over = abort" error, not enough space in mark_table, increase mark_uses" +\ here 4 - swap ! +\ ; + +\ : calculate_branch ( mark_addr branch_addr -- ) \ calculate branch displacement field for one branch +\ swap over - 4 + 4 / +\ $1fffff and +\ over h@ or swap h! +\ ; + +\ : calculate_mark ( tb mark_address -- tb ) \ calculates branch displacement field for one mark +\ over 1 cells + +\ dup mark_uses cells + swap +\ begin +\ over over > +\ while +\ 2over swap drop ( ei i markaddr ej j markaddr ) +\ over @ +\ dup if +\ calculate_branch +\ else +\ drop drop +\ endif +\ 1 cells + +\ repeat drop drop drop +\ ; + +\ : calculate_marks ( -- ) \ calculates branch displacement field for all marks +\ mark_table mark_numbers 1- mark_uses 1+ * cells + +\ mark_table +\ begin +\ over over >= +\ while +\ dup @ +\ dup if \ used mark +\ calculate_mark +\ else +\ drop +\ endif +\ mark_uses 1+ cells + +\ repeat +\ drop drop +\ ; + +previous set-current + + +