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Diffstat (limited to 'ANDROID_3.4.5/arch/m68k/fpsp040/scale.S')
| -rw-r--r-- | ANDROID_3.4.5/arch/m68k/fpsp040/scale.S | 370 |
1 files changed, 0 insertions, 370 deletions
diff --git a/ANDROID_3.4.5/arch/m68k/fpsp040/scale.S b/ANDROID_3.4.5/arch/m68k/fpsp040/scale.S deleted file mode 100644 index 04829dd4..00000000 --- a/ANDROID_3.4.5/arch/m68k/fpsp040/scale.S +++ /dev/null @@ -1,370 +0,0 @@ -| -| scale.sa 3.3 7/30/91 -| -| The entry point sSCALE computes the destination operand -| scaled by the source operand. If the absolute value of -| the source operand is (>= 2^14) an overflow or underflow -| is returned. -| -| The entry point sscale is called from do_func to emulate -| the fscale unimplemented instruction. -| -| Input: Double-extended destination operand in FPTEMP, -| double-extended source operand in ETEMP. -| -| Output: The function returns scale(X,Y) to fp0. -| -| Modifies: fp0. -| -| Algorithm: -| -| Copyright (C) Motorola, Inc. 1990 -| All Rights Reserved -| -| For details on the license for this file, please see the -| file, README, in this same directory. - -|SCALE idnt 2,1 | Motorola 040 Floating Point Software Package - - |section 8 - -#include "fpsp.h" - - |xref t_ovfl2 - |xref t_unfl - |xref round - |xref t_resdnrm - -SRC_BNDS: .short 0x3fff,0x400c - -| -| This entry point is used by the unimplemented instruction exception -| handler. -| -| -| -| FSCALE -| - .global sscale -sscale: - fmovel #0,%fpcr |clr user enabled exc - clrl %d1 - movew FPTEMP(%a6),%d1 |get dest exponent - smi L_SCR1(%a6) |use L_SCR1 to hold sign - andil #0x7fff,%d1 |strip sign - movew ETEMP(%a6),%d0 |check src bounds - andiw #0x7fff,%d0 |clr sign bit - cmp2w SRC_BNDS,%d0 - bccs src_in - cmpiw #0x400c,%d0 |test for too large - bge src_out -| -| The source input is below 1, so we check for denormalized numbers -| and set unfl. -| -src_small: - moveb DTAG(%a6),%d0 - andib #0xe0,%d0 - tstb %d0 - beqs no_denorm - st STORE_FLG(%a6) |dest already contains result - orl #unfl_mask,USER_FPSR(%a6) |set UNFL -den_done: - leal FPTEMP(%a6),%a0 - bra t_resdnrm -no_denorm: - fmovel USER_FPCR(%a6),%FPCR - fmovex FPTEMP(%a6),%fp0 |simply return dest - rts - - -| -| Source is within 2^14 range. To perform the int operation, -| move it to d0. -| -src_in: - fmovex ETEMP(%a6),%fp0 |move in src for int - fmovel #rz_mode,%fpcr |force rz for src conversion - fmovel %fp0,%d0 |int src to d0 - fmovel #0,%FPSR |clr status from above - tstw ETEMP(%a6) |check src sign - blt src_neg -| -| Source is positive. Add the src to the dest exponent. -| The result can be denormalized, if src = 0, or overflow, -| if the result of the add sets a bit in the upper word. -| -src_pos: - tstw %d1 |check for denorm - beq dst_dnrm - addl %d0,%d1 |add src to dest exp - beqs denorm |if zero, result is denorm - cmpil #0x7fff,%d1 |test for overflow - bges ovfl - tstb L_SCR1(%a6) - beqs spos_pos - orw #0x8000,%d1 -spos_pos: - movew %d1,FPTEMP(%a6) |result in FPTEMP - fmovel USER_FPCR(%a6),%FPCR - fmovex FPTEMP(%a6),%fp0 |write result to fp0 - rts -ovfl: - tstb L_SCR1(%a6) - beqs sovl_pos - orw #0x8000,%d1 -sovl_pos: - movew FPTEMP(%a6),ETEMP(%a6) |result in ETEMP - movel FPTEMP_HI(%a6),ETEMP_HI(%a6) - movel FPTEMP_LO(%a6),ETEMP_LO(%a6) - bra t_ovfl2 - -denorm: - tstb L_SCR1(%a6) - beqs den_pos - orw #0x8000,%d1 -den_pos: - tstl FPTEMP_HI(%a6) |check j bit - blts nden_exit |if set, not denorm - movew %d1,ETEMP(%a6) |input expected in ETEMP - movel FPTEMP_HI(%a6),ETEMP_HI(%a6) - movel FPTEMP_LO(%a6),ETEMP_LO(%a6) - orl #unfl_bit,USER_FPSR(%a6) |set unfl - leal ETEMP(%a6),%a0 - bra t_resdnrm -nden_exit: - movew %d1,FPTEMP(%a6) |result in FPTEMP - fmovel USER_FPCR(%a6),%FPCR - fmovex FPTEMP(%a6),%fp0 |write result to fp0 - rts - -| -| Source is negative. Add the src to the dest exponent. -| (The result exponent will be reduced). The result can be -| denormalized. -| -src_neg: - addl %d0,%d1 |add src to dest - beqs denorm |if zero, result is denorm - blts fix_dnrm |if negative, result is -| ;needing denormalization - tstb L_SCR1(%a6) - beqs sneg_pos - orw #0x8000,%d1 -sneg_pos: - movew %d1,FPTEMP(%a6) |result in FPTEMP - fmovel USER_FPCR(%a6),%FPCR - fmovex FPTEMP(%a6),%fp0 |write result to fp0 - rts - - -| -| The result exponent is below denorm value. Test for catastrophic -| underflow and force zero if true. If not, try to shift the -| mantissa right until a zero exponent exists. -| -fix_dnrm: - cmpiw #0xffc0,%d1 |lower bound for normalization - blt fix_unfl |if lower, catastrophic unfl - movew %d1,%d0 |use d0 for exp - movel %d2,-(%a7) |free d2 for norm - movel FPTEMP_HI(%a6),%d1 - movel FPTEMP_LO(%a6),%d2 - clrl L_SCR2(%a6) -fix_loop: - addw #1,%d0 |drive d0 to 0 - lsrl #1,%d1 |while shifting the - roxrl #1,%d2 |mantissa to the right - bccs no_carry - st L_SCR2(%a6) |use L_SCR2 to capture inex -no_carry: - tstw %d0 |it is finished when - blts fix_loop |d0 is zero or the mantissa - tstb L_SCR2(%a6) - beqs tst_zero - orl #unfl_inx_mask,USER_FPSR(%a6) -| ;set unfl, aunfl, ainex -| -| Test for zero. If zero, simply use fmove to return +/- zero -| to the fpu. -| -tst_zero: - clrw FPTEMP_EX(%a6) - tstb L_SCR1(%a6) |test for sign - beqs tst_con - orw #0x8000,FPTEMP_EX(%a6) |set sign bit -tst_con: - movel %d1,FPTEMP_HI(%a6) - movel %d2,FPTEMP_LO(%a6) - movel (%a7)+,%d2 - tstl %d1 - bnes not_zero - tstl FPTEMP_LO(%a6) - bnes not_zero -| -| Result is zero. Check for rounding mode to set lsb. If the -| mode is rp, and the zero is positive, return smallest denorm. -| If the mode is rm, and the zero is negative, return smallest -| negative denorm. -| - btstb #5,FPCR_MODE(%a6) |test if rm or rp - beqs no_dir - btstb #4,FPCR_MODE(%a6) |check which one - beqs zer_rm -zer_rp: - tstb L_SCR1(%a6) |check sign - bnes no_dir |if set, neg op, no inc - movel #1,FPTEMP_LO(%a6) |set lsb - bras sm_dnrm -zer_rm: - tstb L_SCR1(%a6) |check sign - beqs no_dir |if clr, neg op, no inc - movel #1,FPTEMP_LO(%a6) |set lsb - orl #neg_mask,USER_FPSR(%a6) |set N - bras sm_dnrm -no_dir: - fmovel USER_FPCR(%a6),%FPCR - fmovex FPTEMP(%a6),%fp0 |use fmove to set cc's - rts - -| -| The rounding mode changed the zero to a smallest denorm. Call -| t_resdnrm with exceptional operand in ETEMP. -| -sm_dnrm: - movel FPTEMP_EX(%a6),ETEMP_EX(%a6) - movel FPTEMP_HI(%a6),ETEMP_HI(%a6) - movel FPTEMP_LO(%a6),ETEMP_LO(%a6) - leal ETEMP(%a6),%a0 - bra t_resdnrm - -| -| Result is still denormalized. -| -not_zero: - orl #unfl_mask,USER_FPSR(%a6) |set unfl - tstb L_SCR1(%a6) |check for sign - beqs fix_exit - orl #neg_mask,USER_FPSR(%a6) |set N -fix_exit: - bras sm_dnrm - - -| -| The result has underflowed to zero. Return zero and set -| unfl, aunfl, and ainex. -| -fix_unfl: - orl #unfl_inx_mask,USER_FPSR(%a6) - btstb #5,FPCR_MODE(%a6) |test if rm or rp - beqs no_dir2 - btstb #4,FPCR_MODE(%a6) |check which one - beqs zer_rm2 -zer_rp2: - tstb L_SCR1(%a6) |check sign - bnes no_dir2 |if set, neg op, no inc - clrl FPTEMP_EX(%a6) - clrl FPTEMP_HI(%a6) - movel #1,FPTEMP_LO(%a6) |set lsb - bras sm_dnrm |return smallest denorm -zer_rm2: - tstb L_SCR1(%a6) |check sign - beqs no_dir2 |if clr, neg op, no inc - movew #0x8000,FPTEMP_EX(%a6) - clrl FPTEMP_HI(%a6) - movel #1,FPTEMP_LO(%a6) |set lsb - orl #neg_mask,USER_FPSR(%a6) |set N - bra sm_dnrm |return smallest denorm - -no_dir2: - tstb L_SCR1(%a6) - bges pos_zero -neg_zero: - clrl FP_SCR1(%a6) |clear the exceptional operand - clrl FP_SCR1+4(%a6) |for gen_except. - clrl FP_SCR1+8(%a6) - fmoves #0x80000000,%fp0 - rts -pos_zero: - clrl FP_SCR1(%a6) |clear the exceptional operand - clrl FP_SCR1+4(%a6) |for gen_except. - clrl FP_SCR1+8(%a6) - fmoves #0x00000000,%fp0 - rts - -| -| The destination is a denormalized number. It must be handled -| by first shifting the bits in the mantissa until it is normalized, -| then adding the remainder of the source to the exponent. -| -dst_dnrm: - moveml %d2/%d3,-(%a7) - movew FPTEMP_EX(%a6),%d1 - movel FPTEMP_HI(%a6),%d2 - movel FPTEMP_LO(%a6),%d3 -dst_loop: - tstl %d2 |test for normalized result - blts dst_norm |exit loop if so - tstl %d0 |otherwise, test shift count - beqs dst_fin |if zero, shifting is done - subil #1,%d0 |dec src - lsll #1,%d3 - roxll #1,%d2 - bras dst_loop -| -| Destination became normalized. Simply add the remaining -| portion of the src to the exponent. -| -dst_norm: - addw %d0,%d1 |dst is normalized; add src - tstb L_SCR1(%a6) - beqs dnrm_pos - orl #0x8000,%d1 -dnrm_pos: - movemw %d1,FPTEMP_EX(%a6) - moveml %d2,FPTEMP_HI(%a6) - moveml %d3,FPTEMP_LO(%a6) - fmovel USER_FPCR(%a6),%FPCR - fmovex FPTEMP(%a6),%fp0 - moveml (%a7)+,%d2/%d3 - rts - -| -| Destination remained denormalized. Call t_excdnrm with -| exceptional operand in ETEMP. -| -dst_fin: - tstb L_SCR1(%a6) |check for sign - beqs dst_exit - orl #neg_mask,USER_FPSR(%a6) |set N - orl #0x8000,%d1 -dst_exit: - movemw %d1,ETEMP_EX(%a6) - moveml %d2,ETEMP_HI(%a6) - moveml %d3,ETEMP_LO(%a6) - orl #unfl_mask,USER_FPSR(%a6) |set unfl - moveml (%a7)+,%d2/%d3 - leal ETEMP(%a6),%a0 - bra t_resdnrm - -| -| Source is outside of 2^14 range. Test the sign and branch -| to the appropriate exception handler. -| -src_out: - tstb L_SCR1(%a6) - beqs scro_pos - orl #0x8000,%d1 -scro_pos: - movel FPTEMP_HI(%a6),ETEMP_HI(%a6) - movel FPTEMP_LO(%a6),ETEMP_LO(%a6) - tstw ETEMP(%a6) - blts res_neg -res_pos: - movew %d1,ETEMP(%a6) |result in ETEMP - bra t_ovfl2 -res_neg: - movew %d1,ETEMP(%a6) |result in ETEMP - leal ETEMP(%a6),%a0 - bra t_unfl - |end |