diff options
Diffstat (limited to 'libkern/memmove-sparc.s')
| -rw-r--r-- | libkern/memmove-sparc.s | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/libkern/memmove-sparc.s b/libkern/memmove-sparc.s new file mode 100644 index 00000000..1295209a --- /dev/null +++ b/libkern/memmove-sparc.s @@ -0,0 +1,162 @@ + TEXT memmove(SB), $0 + JMP move + + TEXT memcpy(SB), $0 +move: + +/* + * performance: + * (tba) + */ + + MOVW R7, s1+0(FP) + MOVW n+8(FP), R9 /* R9 is count */ + MOVW R7, R10 /* R10 is to-pointer */ + SUBCC R0,R9, R0 + BGE ok + MOVW 0(R0), R0 + +ok: + MOVW s2+4(FP), R11 /* R11 is from-pointer */ + ADD R9,R11, R13 /* R13 is end from-pointer */ + ADD R9,R10, R12 /* R12 is end to-pointer */ + +/* + * easiest test is copy backwards if + * destination string has higher mem address + */ + SUBCC R11,R10, R0 + BGU back + +/* + * if not at least 8 chars, + * dont even mess around. + * 7 chars to guarantee any + * rounding up to a word + * boundary and 8 characters + * to get at least maybe one + * full word store. + */ + SUBCC $8,R9, R0 + BL fout + +/* + * test if both pointers + * are similarly word aligned + */ + XOR R10,R11, R7 + ANDCC $7,R7, R0 + BNE fout + +/* + * byte at a time to double align + */ +f1: + ANDCC $7,R10, R0 + BE f2 + MOVB 0(R11), R16 + ADD $1, R11 + MOVB R16, 0(R10) + ADD $1, R10 + JMP f1 + +/* + * turn R9 into to-end pointer-15 + * copy 16 at a time while theres room. + * R12 is smaller than R13 -- + * there are problems if R13 is 0. + */ +f2: + SUB $15,R12, R9 +f3: + SUBCC R10,R9, R0 + BLEU f4 + MOVD 0(R11), R16 + MOVD R16, 0(R10) + MOVD 8(R11), R16 + ADD $16, R11 + MOVD R16, 8(R10) + ADD $16, R10 + JMP f3 + +/* + * turn R9 into to-end pointer-3 + * copy 4 at a time while theres room + */ +f4: + SUB $3,R12, R9 +f5: + SUBCC R10,R9, R0 + BLEU fout + MOVW 0(R11), R16 + ADD $4, R11 + MOVW R16, 0(R10) + ADD $4, R10 + JMP f5 + +/* + * last loop, copy byte at a time + */ +fout: + SUBCC R11,R13, R0 + BLEU ret + MOVB 0(R11), R16 + ADD $1, R11 + MOVB R16, 0(R10) + ADD $1, R10 + JMP fout + +/* + * whole thing repeated for backwards + */ +back: + SUBCC $8,R9, R0 + BL bout + + XOR R12,R13, R7 + ANDCC $7,R7, R0 + BNE bout +b1: + ANDCC $7,R13, R0 + BE b2 + MOVB -1(R13), R16 + SUB $1, R13 + MOVB R16, -1(R12) + SUB $1, R12 + JMP b1 +b2: + ADD $15,R11, R9 +b3: + SUBCC R9,R13, R0 + BLEU b4 + + MOVD -8(R13), R16 + MOVD R16, -8(R12) + MOVD -16(R13), R16 + SUB $16, R13 + MOVD R16, -16(R12); + SUB $16, R12 + JMP b3 +b4: + ADD $3,R11, R9 +b5: + SUBCC R9,R13, R0 + BLEU bout + MOVW -4(R13), R16 + SUB $4, R13 + MOVW R16, -4(R12) + SUB $4, R12 + JMP b5 + +bout: + SUBCC R11,R13, R0 + BLEU ret + MOVB -1(R13), R16 + SUB $1, R13 + MOVB R16, -1(R12) + SUB $1, R12 + JMP bout + +ret: + MOVW s1+0(FP), R7 + RETURN |