diff options
| author | Charles.Forsyth <devnull@localhost> | 2006-12-22 17:07:39 +0000 |
|---|---|---|
| committer | Charles.Forsyth <devnull@localhost> | 2006-12-22 17:07:39 +0000 |
| commit | 37da2899f40661e3e9631e497da8dc59b971cbd0 (patch) | |
| tree | cbc6d4680e347d906f5fa7fca73214418741df72 /libmp/Inferno-mips/mpvecdigmuladd.s | |
| parent | 54bc8ff236ac10b3eaa928fd6bcfc0cdb2ba46ae (diff) | |
20060303a
Diffstat (limited to 'libmp/Inferno-mips/mpvecdigmuladd.s')
| -rw-r--r-- | libmp/Inferno-mips/mpvecdigmuladd.s | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/libmp/Inferno-mips/mpvecdigmuladd.s b/libmp/Inferno-mips/mpvecdigmuladd.s new file mode 100644 index 00000000..d80073b1 --- /dev/null +++ b/libmp/Inferno-mips/mpvecdigmuladd.s @@ -0,0 +1,58 @@ +/* + * mpvecdigmuladd(mpdigit *b, int n, mpdigit m, mpdigit *p) + * + * p += b*m + * + * each step looks like: + * hi,lo = m*b[i] + * lo += oldhi + carry + * hi += carry + * p[i] += lo + * oldhi = hi + * + * the registers are: + * b = R1 + * n = R4 + * m = R5 + * p = R6 + * i = R7 + * hi = R8 - constrained by hardware + * lo = R9 - constrained by hardware + * oldhi = R10 + * tmp = R11 + * + */ +TEXT mpvecdigmuladd(SB),$0 + + MOVW n+4(FP),R4 + MOVW m+8(FP),R5 + MOVW p+12(FP),R6 + + + MOVW R0, R10 /* oldhi = 0 */ + BEQ R6, _muladd1 +_muladdloop: + MOVW 0(R1), R9 /* lo = b[i] */ + ADDU $4, R1 + MOVW 0(R6), R11 /* tmp = p[i] */ + MULU R9, R5 + MOVW HI, R8 /* hi = (b[i] * m)>>32 */ + MOVW LO, R9 /* lo = b[i] * m */ + ADDU R10, R9 /* lo += oldhi */ + SGTU R10, R9, R2 + ADDU R2, R8 /* hi += carry */ + ADDU R9, R11 /* tmp += lo */ + SGTU R9, R11, R2 + ADDU R2, R8 /* hi += carry */ + MOVW R11, 0(R6) /* p[i] = tmp */ + ADDU $4, R6 + MOVW R8, R10 /* oldhi = hi */ + SUBU $1, R4 + BNE R4, _muladdloop + +_muladd1: + MOVW 0(R6), R11 /* tmp = p[i] */ + ADDU R10, R11 /* tmp += oldhi */ + MOVW R11, 0(R6) /* p[i] = tmp */ + + RET |