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Length: 1375 (0x55f)
Types: TextFile
Notes: UNIX file
Names: »dtoi.s«
└─⟦f27320a65⟧ Bits:30001972 Commodore 900 hard disk image with partial source code
└─⟦f4b8d8c84⟧ UNIX V7 Filesystem
└─ ⟦this⟧ »libc/crt/dtoi.s«
.globl ifix, ufix, lfix, vfix / floating point package for segmented z-8001 / timothy s. murphy 10/84 / IEEE format / double: 63 62 52 51 0 / sign bin exp +1022 fraction (missing hi bit) / float: 31 30 23 22 0 / sign bin exp +126 fraction (missing hi bit) / .globl SS / convert double to integer type / / ifix returns int in r1 / ufix returns unsigned int in r1 / lfix returns long in rr0 / vfix returns unsigned long in rr0 / subroutine dtoi returns sign in r3 + if 0 - if <>0 / exponent in r2 / greatest integer <= abs value of arg in rr0 / provided exp <= 32 ifix: calr dtoi cp r2, $15 jr ule, 0f ld r1, $0x8000 ret 0: test r3 ret z neg r1 ret ufix: calr dtoi test r3 jr z, 0f sub r1, r1 ret 0: cp r2, $16 ret ule ld r0, $-1 ret lfix: calr dtoi cp r2, $31 jr ule, 0f ldl rr0, $0x80000000 ret 0: test r3 ret z ld r3, $-1 com r0 neg r1 sbc r0, r3 ret vfix: calr dtoi test r3 jr z, 0f subl rr0, rr0 ret 0: cp r2, $32 ret ule ldl rr0, $-1 ret dtoi: ldl rr0, SS|10(r15) ld r2, SS|8(r15) ld r3, $32768 and r3, r2 xor r2, r3 ldk r4, $4 0: srl r2 rrc r0 rrc r1 djnz r4, 0b / rr0 now is hi 32 bits of fraction sub r2, $1022 jr gt, 0f subl rr0, rr0 subl rr2, rr2 / ret 0 if exp <= 0 ret 0: setflg C rrc r0 rrc r1 ld r4, r2 sub r4, $32 ret ge sdll rr0, r4 ret