diff options
Diffstat (limited to 'sys/arch/hppa/spmath/impys.S')
| -rw-r--r-- | sys/arch/hppa/spmath/impys.S | 30 |
1 files changed, 15 insertions, 15 deletions
diff --git a/sys/arch/hppa/spmath/impys.S b/sys/arch/hppa/spmath/impys.S index 10ba5f98a1d..25f07c6f54e 100644 --- a/sys/arch/hppa/spmath/impys.S +++ b/sys/arch/hppa/spmath/impys.S @@ -1,4 +1,4 @@ -/* $OpenBSD: impys.S,v 1.7 2002/05/07 22:19:30 mickey Exp $ */ +/* $OpenBSD: impys.S,v 1.8 2002/09/20 19:26:59 mickey Exp $ */ /* (c) Copyright 1986 HEWLETT-PACKARD COMPANY To anyone who acknowledges that this file is provided "AS IS" @@ -18,11 +18,11 @@ ;**************************************************************************** ; -;Implement an integer multiply routine for 32-bit operands and 64-bit product +;Implement an integer multiply routine for 32-bit operands and 64-bit product ;with operand values of zero (multiplicand only) and -2**31 treated specially. ;The algorithm uses the absolute value of the multiplier, four bits at a time, ;from right to left, to generate partial product. Execution speed is more -;important than program size in this implementation. +;important than program size in this implementation. ; ;**************************************************************************** ; @@ -64,14 +64,14 @@ mpy1 comb,< op1,gr0,mpya ; br. if multiplicand < 0 addib,= 0,op1,fini0 ; op1 = 0, product = 0 mpy2 addi 1,gr0,pc ; initialize pc to 00...01 movib,tr 8,cnt,mloop ; set count for mpy loop - extru op2,31,4,brindex ; 4 bits as index into table + extru op2,31,4,brindex ; 4 bits as index into table ; .align 8 ; b sh4c ; br. if sign overflow sh4n shd pu,pl,4,pl ; shift product right 4 bits addib,<= -1,cnt,mulend ; reduce count by 1, exit if - extru pu,27,28,pu ; <= zero + extru pu,27,28,pu ; <= zero ; mloop blr brindex,gr0 ; br. into table ; entries of 2 words @@ -94,13 +94,13 @@ mtable ; two words per entry ; ; ---- bits = 0010 ---- add op1, add op1, then shift 4 bits ; - addb,tr op1,pu,sh4n ; add 2*op1, to shift - addb,uv op1,pu,sh4c ; product right 4 bits + addb,tr op1,pu,sh4n ; add 2*op1, to shift + addb,uv op1,pu,sh4c ; product right 4 bits ; ; ---- bits = 0011 ---- add op1, add 2*op1, shift 4 bits ; - addb,tr op1,pu,sh4n-4 ; add op1 & 2*op1, shift - sh1add,nsv op1,pu,pu ; product right 4 bits + addb,tr op1,pu,sh4n-4 ; add op1 & 2*op1, shift + sh1add,nsv op1,pu,pu ; product right 4 bits ; ; ---- bits = 0100 ---- shift 2, add op1, shift 2 ; @@ -183,21 +183,21 @@ sh4c addib,> -1,cnt,mloop ; decrement count, loop if > 0 mpyb add,= op2,op2,gr0 ; if <> 0, back to main sect. b mpy1 sub 0,op2,op2 ; op2 = |multiplier| - add,>= op1,gr0,gr0 ; if op1 < 0, invert sign, + add,>= op1,gr0,gr0 ; if op1 < 0, invert sign, xor pm,sign,sign ; for correct result ; ; special case for multiplier = -2**31, op1 = signed multiplicand ; or multiplicand = -2**31, op1 = signed multiplier ; shd op1,0,1,pl ; shift op1 left 31 bits -mmax extrs op1,30,31,pu +mmax extrs op1,30,31,pu b signs ; negate product (if needed) bb,>=,n sign,0,fini ; test sign of product ; mpya add,= op1,op1,gr0 ; op1 = -2**31, special case b mpy2 sub 0,op1,op1 ; op1 = |multiplicand| - add,>= op2,gr0,gr0 ; if op2 < 0, invert sign, + add,>= op2,gr0,gr0 ; if op2 < 0, invert sign, xor pm,sign,sign ; for correct result movb,tr op2,op1,mmax ; use op2 as multiplicand shd op1,0,1,pl ; shift it left 31 bits @@ -228,8 +228,8 @@ sh1 addib,> -1,cnt,mloop ; loop if count > 0 sh2ns addib,tr 1,brindex,sh2sb+4 ; increment index extru pu,29,30,pu ; shift unsigned ; -sh2s shd pu,pl,2,pl ; shift with minus sign - shd pm,pu,2,pu ; +sh2s shd pu,pl,2,pl ; shift with minus sign + shd pm,pu,2,pu ; sub pu,op1,pu ; subtract op1 shd pu,pl,2,pl ; shift with minus sign addib,tr -1,cnt,mloop ; decrement count, loop @@ -255,7 +255,7 @@ sh2us extru pu,29,30,pu ; shift 2 unsigned addb,tr op1,pu,sh2a ; add op1 shd pu,pl,2,pl ; shift 2 bits ; -sh2c shd pu,pl,2,pl +sh2c shd pu,pl,2,pl shd pc,pu,2,pu ; shift with carry addb,tr op1,pu,sh2a ; add op1 to product shd pu,pl,2,pl ; br. to sh2 to shift pu |